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Distinguishing laser transition points of a non-ideal semiconductor laser:population inversion,lasing threshold,saturation and steady state 认领 引用
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作者 Liefeng FENG Yiming LIU +1 位作者 Zhuoran WANG Cunda WANG 《Optoelectronics Letters》 EI 2026年第4期202-206,共5页
Semiconductor lasers have been widely used,but their most important characteristic,the threshold,has not been sufficiently investigated and remains highly controversial until now.Here,we illustrate this issue using an... Semiconductor lasers have been widely used,but their most important characteristic,the threshold,has not been sufficiently investigated and remains highly controversial until now.Here,we illustrate this issue using an actual GaAs laser diode(LD).We analyze its electrical behavior,optical power,and electroluminescence(EL)spectrum near the threshold region,then propose that one should distinguish between laser transition points,including population inversion,lasing threshold,and saturation,respectively.Simple methods are provided to characterize the population inversion,the lasing threshold,and the saturation point.Additionally,we discuss the physical significance of these three points. 展开更多
关键词 saturation population inversionlasing laser transition points semiconductor lasers lasing threshold distinguish laser transition pointsincluding gaas laser diode ld we population inversion
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Population Security in Northeast China’s Border Areas amid Population Shrinkage:Spatial Patterns,Classification,and Driving Forces 认领 引用
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作者 LIU Jian GENG Jing +3 位作者 SHAN Xu HA Yuchun ZHAO Lingmin LI Haoran 《Chinese Geographical Science》 SCIE CAS CSCD 2026年第7期1175-1190,共16页
Border areas are important spaces for national security and opening up to the outside world,and the level of population security in these areas is related to border stability and regional sustainable development.North... Border areas are important spaces for national security and opening up to the outside world,and the level of population security in these areas is related to border stability and regional sustainable development.Northeast China is a typical area of population shrinkage,and the problem of population shrinkage in border areas is even more prominent.Against the backdrop of population shrinkage,this paper takes 45 border counties(cities,districts)in Northeast China as an example,and uses the entropy method and multiple linear regression to assess the population security level in border areas and explore its influencing factors.The study found that:1)from 2010 to 2020,the population of the northeast border area continuously declined and entered a stage of overall population shrinkage,with a total decrease of approximately 1.34 million over the decade.In particular,the border areas of Jilin Province experienced the widest and most severe population shrinkage.2)The population security level in the northeast border area generally declined and exhibited significant spatial differentiation.Areas with relatively high population security were mainly concentrated in the northeast border areas of Heilongjiang Province,where openness and industrial development were relatively strong,whereas areas with low population security were concentrated in parts of the border areas of Jilin Province and Da Hinggan Ling Prefecture,where population loss was severe and the level of openness was relatively low.3)Population security types can be classified into three categories:security stability,security improvement,and security decline,with the security decline type accounting for nearly one-third of the study area.4)Population security is not solely determined by population size,but rather by the coordinated relationship among population quantity,structure,and regional development capacity.Economic development is the key factor affecting population security.Economic indicators such as nighttime light index and the proportion of secondary and tertiary industries have significant positive effects on population security,while natural and administrative factors also play certain roles.Finally,this study proposes differentiated governance strategies for different types of areas,with the aim of improving the population security level and maintaining border stability in the northeast border area. 展开更多
关键词 population shrinkage population security classification and implementation northeast border area China
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ddRAD sequencing of 1076 Camellia accessions reveals the genetic diversity and population introgression of the tea plant in China 认领 引用 被引量：3
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作者 Xiao-Yan Tong Jian-Bing Hu +14 位作者 Hui-Lin Wen Chun-Lin Chen Ling-Ling Tao Jun Wu Yi-Ping Tian Hui-Ping Jiang Lin-Bo Chen Da-He Qiao Ming-Tao Shu En-Hua Xia Kun Dong Yue Fei Sheng-Rui Liu Chao-Ling Wei Jun-Yan Zhu 《Plant Diversity》 SCIE CAS CSCD 2026年第3期451-459,共9页
The tea plant(Camellia sinensis)is a widely cultivated and economically significant crop that originated from southwestern China.Owing to its high heterozygosity and complex genetic diversity,the evolutionary history ... The tea plant(Camellia sinensis)is a widely cultivated and economically significant crop that originated from southwestern China.Owing to its high heterozygosity and complex genetic diversity,the evolutionary history of the tea plant and its domestication remain unclear.In this study,we used 1076 Camellia accessions to elucidate the phylogenetic relationships and population structure of Camellia accessions across 16 major tea-producing provinces in China.Six species-specific populations were classified based on these SNPs through phylogenetic trees and population structure.We found that C.taliensis populations have undergone divergent evolution compared to other wild relatives,such as C.kwangsiensis and C.crassicoluma.Population structure and introgression analyses further revealed frequent interspecific genetic exchanges between C.sinensis and its wild relatives.Thus,a transitional C.sinensis population that shared a genetic background with C.taliensis was characterized.Distinct genetic divergence was observed within the two main varieties of C.sinensis.Contrary to the relatively exclusive genetic background within the C.sinensis var.assamica population in southwestern China,extensive regional introgression and gene flow were observed in the C.sinensis var.sinensis population between southwestern and eastern China.Finally,we developed a core collection comprising 160 accessions based on our genetic diversity analyses.Our findings not only provide insights into the evolutionary history and genetic diversity of the tea plant but may facilitate the development of the conservation and utilization of tea plant resources. 展开更多
关键词 Tea plant Population structure ddRAD-seq Genetic diversity Core collection Introgression
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Chromosome-level genome assembly and population genomics analysis of Camellia rubituberculata provide insights into adaptation to karst habitats 认领 引用 被引量：2
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作者 Chao Yan Ming-tai An +4 位作者 Ming Tang Xin-xiang Bai Xu Xiao Zhao-hui Ran Zhi Li 《Plant Diversity》 SCIE CAS CSCD 2026年第2期246-261,共16页
Karst flora confined to isolated‘habitat islands'evolve specialized adaptations and unique traits,serving as ideal models for investigating adaptive evolution and species diversification mechanisms.Camellia rubit... Karst flora confined to isolated‘habitat islands'evolve specialized adaptations and unique traits,serving as ideal models for investigating adaptive evolution and species diversification mechanisms.Camellia rubituberculata,endemic to the karst habitats of Guizhou,China,can serve as a model for adaptive evolution and diversity in karst-endemic woody species.However,the lack of a chromosome-level genome for this species has limited in-depth studies on its adaptations to karst and posed a barrier to its genetic improvement.In this study,a chromosome-level genome assembly of C.rubituberculata was generated,with 15 pseudo-chromosomes and a genome size of 2.50 Gb(scaffold N50=168.34 Mb,55,302 protein-coding genes).Comparative genomics revealed two whole-genome duplications(WGDs),namely,an ancient γ-event(~120 Mya)and a subsequent genus-wide event(~86 Mya),after which gene families linked to karst adaptation(e.g.,photosynthesis)were significantly expanded.Selective sweep analysis showed that selected genes were associated with phytohormone transmission and metabolism.Genes functionally annotated as involved in stress responses—including SAUR,BSK,NCL,CDPK,and NDPK—participate in calcium homeostasis and ion transport pathways under karstspecific stresses.MYB transcription factors,which are crucial in plant responses to stresses,including drought,may be key for adaptation to the high salinity and drought stress in karst environments.The divergent selection in wild and cultivated groups highlight key adaptations in plant hormone transduction and calcium transport.By elucidating karst adaptation in C.rubituberculata,this work establishes essential genomic resources for advancing genetic evolution research and molecular breeding across Camellia species. 展开更多
关键词 Camellia rubituberculata Endemic species Genome assembly Karst adaptation Population genetics
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Succession of algae population and blooms with their driving factors in China's lakes 认领 引用 被引量：1
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作者 Jing Cao Zhaosheng Chu +1 位作者 Haifeng Jia Binghui Zheng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2026年第2期13-26,共14页
Algae play an important role in lake ecosystems,and algal succession is vital to studying the mechanism of algal bloom outbreaks.This paper provides a comprehensive review of algae blooms development,bloom-forming alg... Algae play an important role in lake ecosystems,and algal succession is vital to studying the mechanism of algal bloom outbreaks.This paper provides a comprehensive review of algae blooms development,bloom-forming algae succession,the diversity of common blooms-forming algae,and key drivers for algae succession in Chinese lakes,based on an extensive literature survey and data sets.Furthermore,it summarizes the influencing factors for algae blooms and bloom-forming algae succession in five lake zones of China.The results indicated that the number of research publications on algal blooms in China constituted the largest share of global research,representing 41.9 %.The predominant types of algae blooms in all publications were cyanobacterial blooms,followed by dinoflagellate blooms.The blooms-forming algae in China's lakes have experienced a clear succession pattern:Bacillariophyta,Chlorophyta and Pyrrophyta were dominated in the initial investigations;dominance of Microcystis,Anabaena, dinoflagellates and diatoms increased significantly since1960s;in the past decade,Cylindrospermopsis and dinoflagellates expanded.Current research on algae blooms in Chinese lakes mainly focuses on cyanobacterial blooms,especially Microcystis blooms,while researches on filamentous cyanobacterial blooms and other algae blooms is still insufficient.This systematic review will help researchers to understand the basic features such as the occurrence,the diversity,the physio-ecology and the driving factors of common blooms-forming algae,will further provide a scientific basis for their control in various lake regions. 展开更多
关键词 Succession Algae population Algal blooms Cyanobacterial blooms
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Prolonged seasons of compound heat-humidity extremes amplify vulnerable population exposure in eastern China 认领 引用 被引量：1
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作者 Miaoni Gao Xinyue Sun +3 位作者 Buda Su Lu Tang Xingyu Cheng Tong Jiang 《Atmospheric and Oceanic Science Letters》 CAS CSCD 2026年第3期58-63,共6页
Compound heat–humidity extremes(CTHEs)pose escalating threats to human health,particularly for vulnerable populations(children and elderly)with limited physiological adaptability.This study reveals the expansion of C... Compound heat–humidity extremes(CTHEs)pose escalating threats to human health,particularly for vulnerable populations(children and elderly)with limited physiological adaptability.This study reveals the expansion of CTHE-active seasons across eastern China from 1961 to 2022.Southern China(SC)and the Yangtze–Huaihe region(YH)exhibit earlier onsets and delayed terminations,prolonging hazardous CTHE seasons by one month post-2015 in SC.The prolonged CTHE-active seasons,coupled with population growth,have driven sharp increases in exposure across eastern China,with annual CTHE and hazardous CTHE exposure increasing by 106 million and 78 million person-days since the 2000s.Vulnerable groups constitute 39%of total exposure,with 11%(CTHEs)and 34%(hazardous CTHEs)attributable to season prolongation.Mechanistically,an intensified and westward-extended western North Pacific subtropical high enhances diabatic heating and moisture advection,driving prolonged CTHE-active seasons in SC and YH.These findings quantify climate–demographic synergies in heat–health risks,providing a scientific basis for climate-resilient health strategies targeting age-sensitive populations in eastern China’s warming and humidifying hotspots. 展开更多
关键词 Compound heat-humidity extremes Onset and termination Western north Pacific subtropical high Vulnerable population exposure
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Integrating habitat and population dynamics to uncover dispersal-driven persistence in a reintroduced Crested Ibis metapopulation 认领 引用
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作者 Yilamujiang Tuohetahong Chunpo Tian +7 位作者 Ruyue Lu Sheng Ding Kesheng Niu Xia Li Lu Yan Wenbin Duan Xinping Ye Xiaoping Yu 《Current Zoology》 SCIE CAS CSCD 2026年第2期223-236,共14页
Metapopulation theory explains species persistence through dispersal-linked populations.This study links theory and conservation to predict reintroduction success in human-altered landscapes.Using the Crested Ibis(Nip... Metapopulation theory explains species persistence through dispersal-linked populations.This study links theory and conservation to predict reintroduction success in human-altered landscapes.Using the Crested Ibis(Nipponia nippon)as a model system,we combined spatially explicit habitat modeling with stochastic population viability analysis to assess how dispersal mediates persistence across wild and reintroduced populations in a metapopulation context.Our integrated approach identified 15,216 km² of potential habitat and a 95.64 km least-cost pathway linking wild population and reintroduced population.Projections over 50-year simulations revealed that dispersal significantly enhanced metapopulation viability,enabling population size to reach 17,846 individuals(92.37%of carrying capacity).Conversely,population isolation would lead to a 15%decline in reintroduced population.Our simulations demonstrated that environmental stressors(including catastrophic events and predation pressure)reduced overall metapopulation size by 61.8%and 22.7%respectively when dispersal was absent.However,active dispersal effectively mitigated these impacts,maintaining long-term quasi-extinction probabilities at 0.17.The analysis revealed a clear source-sink dynamic,with the wild population serving as a stable source population,while the reintroduced population remained dependent on metapopulation connectivity for persistence. 展开更多
关键词 crested Ibis dispersal metapopulation population modeling quasi-extinction risk reintroduction
Satellite tracking reveals a migratory divide and population-specific migratory strategies in White-naped Cranes 认领 引用
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作者 Lijia Wen Gankhuyag Purev-Ochir +6 位作者 Baasansuren Erdenechim Dashdorj Khurelbaatar Xuezhu Li Xianda Li Yi Hao Yumin Guo Yanjie Xu 《Avian Research》 SCIE CAS CSCD 2026年第1期67-73,共7页
Migratory divides,where individuals from distinct breeding populations within a species exhibit divergent migratory routes and strategies,play a critical role in shaping avian ecology and evolution.These divides can d... Migratory divides,where individuals from distinct breeding populations within a species exhibit divergent migratory routes and strategies,play a critical role in shaping avian ecology and evolution.These divides can drive intraspecific genetic divergence and promote reproductive isolation,potentially leading to population differentiation and speciation.Understanding the migration strategies of populations utilizing distinct flyways is essential not only for elucidating the mechanisms underlying migration patterns but also for informing effective species conservation efforts.From 2014 to 2023,we used satellite tracking to monitor the migration patterns of 87 White-naped Cranes(Antigone vipio)from the species'two breeding populations—western(Mongolia)and eastern(Songnen Plain,China).We delineated their migratory routes,quantified key migration parameters,and identified their population-and season-specific differences in migratory strategies.Our results indicate that the Greater Khingan Mountains and the Bohai-Yellow Sea formed a distinct migratory barrier separating the eastern and western populations.Significant differences in migration strategies were observed between populations and seasons.The western population adopts a"longer-distance,slower-speed,more-stopover"strategy,while the eastern population employs a"shorter-distance,higher-speed,fewer-stopover"strategy.Our study identifies the migratory divides between the two populations of White-naped Cranes and highlights the importance of migratory divides in shaping distinct migration strategies.These findings enhance our understanding of the factors driving population-specific migration strategies and provide a foundation for tailored conservation efforts for these populations. 展开更多
关键词 Bird migration Crane Ecological barriers Movement ecology Population difference
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Increasing meridional disparity of population exposure to heat stress 认领 引用
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作者 Xiaofan Xu Yuxiao Kong +5 位作者 Jintao Zhang Jianping Duan Minghong Tan Xue Yang Hongzhou Zhu Deliang Chen 《Geography and Sustainability》 CSCD 2026年第1期95-105,共11页
Global warming and socioeconomic development are expected to exacerbate human exposure to heat stress,but the extent and inequality of such changes remain unclear.Here,we quantified the future population exposure to h... Global warming and socioeconomic development are expected to exacerbate human exposure to heat stress,but the extent and inequality of such changes remain unclear.Here,we quantified the future population exposure to heat stress(PEHS)under different Shared Socioeconomic Pathways(SSPs)and Representative Concentration Pathways(RCPs)scenarios using a novel decomposition framework that separates the contributions of climate change,population change,and their interaction.Results show that global PEHS will increase substantially during the 21st century,with low-latitude regions experiencing the largest absolute increases,and high-latitude regions facing the largest relative increases.Globally,projected increases in PEHS under SSP3-7.0 are roughly three times those under SSP1-2.6,with low latitudes contributing about 70%-75%of the global total.SSP1-2.6 most effectively limits future heat exposure,with the highest risks in low-latitude developing regions,underscoring the need for low-emission pathways and targeted population and urbanization management.The findings highlight the urgent need for both climate mitigation and population adaptation strategies to address the growing and uneven heat exposure risks worldwide. 展开更多
关键词 Population exposure Extreme heatwave Meridional disparity
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Wind-induced circulation driving the spatial distribution of dominant algae population in a plateau lake,Erhai,China 认领 引用
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作者 Jing Cao Yue Wu +4 位作者 Zeying Hou Kunlin Yang Zhaosheng Chu Zhiwei Gao Hao Yang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2026年第1期741-755,共15页
Wind-induced circulation is the main form of lake flow for shallow lakes and plays an important role in algae population distribution.This study constructed a three-dimensional hydrodynamic model(EFDC)of the plateau l... Wind-induced circulation is the main form of lake flow for shallow lakes and plays an important role in algae population distribution.This study constructed a three-dimensional hydrodynamic model(EFDC)of the plateau lake Erhai,China using accuracy wind field observation,runoff data and monthly algae data during 2022–2023.The model successfully reproduced the circulation characteristics of Erhai under prevailing wind directions.The results showed that the lake flow velocity in Lake Erhai is higher in winter than in summer,with lower velocities near shore particularly in the northern and central parts of the lake.There is a negative correlation between algal biomass and flow velocity(FV)in different zones,with lower FV favoring the accumulation of algal biomass,particularly for Microcystis,Dolichospermum,and Peridinium.Additionally,due to buoyancy,cyanobacteria are highly affected by wind direction and tend to accumulate in downwind regions of the prevailing wind direction.This study demonstrates that wind-induced circulation is a crucial factor affecting the spatial distribution of dominant algae populations in shallow plateau lakes with weak hydrodynamic force.Further,the risk of bloom occurrence in Lake Erhai will be higher due to the background of global climate change and the lake’s wind speed decline.In conclusion,we suggest implementing targeted zoning measures to control algal blooms and establishing stricter regulations for nitrogen and phosphorus control to counterbalance the promotion of algal bloom accumulation in low-velocity zones caused by reduced wind speed. 展开更多
关键词 Wind-induced circulation Dominant algae populations Three-dimensional hydrodynamic model Microcystis Peridinium
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Chromosome-level genome and population genomics reveal demographic history,incomplete divergence and coastal adaptation of Rhododendron simsii var.putuoense in East China 认领 引用
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作者 Hong Zhu Haojie Gao Hepeng Li 《Plant Diversity》 SCIE CAS CSCD 2026年第3期635-639,共5页
Geographical isolation plays a crucial role in species divergence and adaptive evolution(Worsham et al.,2017;Loretán et al.,2020).This phenomenon is especially pronounced in land-sea interactive habitats,where ge... Geographical isolation plays a crucial role in species divergence and adaptive evolution(Worsham et al.,2017;Loretán et al.,2020).This phenomenon is especially pronounced in land-sea interactive habitats,where geological shifts and climatic variations have significantly influenced genetic structures and distribution patterns by repeatedly modifying habitat connectivity(Jiang et al.,2021).Land-bridge islands,which extend from continental shelves and experience alternating phases of connection and isolation due to glacially driven sea-level fluctuations,function as natural laboratories for investigating species divergence,gene flow,and ecological adaptation(Jin et al.,2016;Cros et al.,2020).The Zhoushan Archipelago,China's largest archipelago,located on the northern margin of the subtropical zone,has undergone similar geological dynamics(repeated geological linkages and separations from the mainland),forming a distinct"island-continent disjunct distribution"pattern.This characteristic makes it an ideal system to study plant responses to geographical isolation in East Asia(Zhang et al.,2025). 展开更多
关键词 Rhododendron simsii var.putuoense de novo assembly Comparative genomics Population genomics Demographic history Coastal adaptation
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Mapping world’s coastal population facing water-related risks 认领 引用
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作者 Olli Varis Maija Taka Matti Kummu 《Geography and Sustainability》 CSCD 2026年第1期206-217,共12页
Endowed with opportunities from both land and ocean,coastal areas attract expanding human populations and economic activities.At the same time,they face growing societal and environmental pressures from both the above... Endowed with opportunities from both land and ocean,coastal areas attract expanding human populations and economic activities.At the same time,they face growing societal and environmental pressures from both the above river catchments and the bordering sea due to climate change,ecosystem degradation,and expansion of built-up areas.Despite the accumulation of human population,economic activities,and environmental impacts,we lack social-ecological systems analysis on water-related risks to world’s coastal human population.To address this research gap,we analyze the spatial extent of six globally important water stressors to people within the world’s coastal zone(100 km from the coastal line)and classify this zone globally into 12 groups by distance from the coastline and elevation from the mean sea level.Adopting the approaches of the UN Sendai Framework and IPCC,we produce risk maps from the stressor maps by multiplying them with population exposure and vulnerability.For most risks,geographical hotspots are the Chinese coast,Bay of Bengal,Gujarat,and the Island of Java.The analysis reveals fundamental differences between water stressors and related risks,often mixed in scholarly literature.Both manifest specific geographic patterns and latitudinal profiles.Our study highlights the importance of high-resolution spatial analysis of vulnerability,exposure,and risks posed by water related stressors in the world’s coastal zone,in a manner prompted by key policy bodies to promote policy design and shared responsibility for managing stress-prone areas. 展开更多
关键词 Coastal zone Population RiskSocial-ecological systems Spatial analysis Water
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Causal association between oral microbiota and hepatocellular carcinoma in East Asian populations:a Mendelian randomization study 认领 引用
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作者 ZHONG Hanxiang ZHAO Yuanyu +4 位作者 FU Hong DONG Jiayong DING Guoshan CHEN Yao GUO Wenyuan 《南方医科大学学报》 CAS CSCD 北大核心 2026年第7期1455-1461,共7页
Objective Emerging evidence highlights the crucial role of the oral microbiota in various malignancies,but its causal relationship with hepatocellular carcinoma(HCC)remains largely unexplored.This study aimed to inves... Objective Emerging evidence highlights the crucial role of the oral microbiota in various malignancies,but its causal relationship with hepatocellular carcinoma(HCC)remains largely unexplored.This study aimed to investigate the causal association between oral microbiota composition and HCC risk in East Asian populations using Mendelian randomization(MR)analysis.Methods We performed a two-sample Mendelian randomization to investigate the causal association of 309 tongue dorsum microbiomes and 285 salivary microbiomes with liver cancer progression using the latest pooled data from genome-wide association study(GWAS)of oral microbiomes in East Asian populations.We selected single nucleotide polymorphism(SNP)independent of confounders as the instrumental variable(IV)for causal inference analysis using various Mendelian randomization statistical techniques.The heterogeneity and pleiotropy of the IV was evaluated to ensure the reliability of the results.Results Our analysis revealed a complex association between specific bacterial genera in the oral microbiome and liver cancer.Streptococcus showed a mixed association with hepatocellular carcinoma,while Oribacterium and Centipeda showed a positive correlation with HCC occurrence.Gemella genus was negatively correlated with HCC.Heterogeneity or pleiotropy of the IV was not detected in the sensitivity analysis.Conclusion This study provides the first Mendelian randomization evidence linking oral microbiota to HCC susceptibility in East Asian populations.Our findings suggest causal roles of specific oral bacterial taxa in hepatocarcinogenesis,and offer new insights into the mechanisms of the oral-liver axis and potential microbial targets for HCC prevention and treatment. 展开更多
关键词 causal association oral microbiota Mendelian randomization hepatocellular carcinoma East Asian populations
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THRESHOLD ANALYSIS OF IMPULSIVE CONTROL IN A MOSQUITO POPULATION SUPPRESSION MODEL WITH SPARSE STATE FEEDBACK 认领 引用
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作者 Shouzong LIU Yang XU Mingzhan HUANG 《Acta Mathematica Scientia》 SCIE CSCD 2026年第2期897-919,共23页
In this study,a mosquito population suppression model that integrates stage structure is introduced,which serves as the foundation for exploring various strategies for the periodic impulsive release of sterile mosquit... In this study,a mosquito population suppression model that integrates stage structure is introduced,which serves as the foundation for exploring various strategies for the periodic impulsive release of sterile mosquitoes,including those that either incorporate or disregard population state feedback,as well as a composite control approach.We identify release thresholds under different strategies that ensure the complete eradication of the wild mosquito population.Numerical analyses are conducted to evaluate the performance of these release strategies.Our findings reveal that integrating state feedback mechanisms can effectively prevent the blindness of release behaviors.Key factors such as the release interval,frequency of population assessments,and control intensity significantly influence the reduction of the cumulative release quantity of sterile mosquitoes,the shortening of control duration,and the decrease in effective release events.The influence of these factors on control outcomes across different strategies and scenarios is also examined. 展开更多
关键词 mosquito population suppression model periodic impulsive release sparse state feedback extinction equilibrium
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Impact of High-Quality Population Development on the Silver Economy:The Roles of Digital Technological Innovation and Population Aging 认领 引用
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作者 Zhang Xue 《Contemporary Social Sciences》 2026年第3期98-114,共17页
Using panel data from 30 Chinese provinces over the period 2014-2023,this study empirically examines the impact of high-quality population development on the silver economy and its underlying mechanisms.The results in... Using panel data from 30 Chinese provinces over the period 2014-2023,this study empirically examines the impact of high-quality population development on the silver economy and its underlying mechanisms.The results indicate that high-quality population development significantly promotes the silver economy,with a stronger effect in the eastern region.Digital technological innovation exerts a positive moderating effect,whereas population aging exerts a negative moderating effect.In addition,a significant threshold effect is identified:once human capital structure upgrading surpasses a critical threshold,its marginal effect on the silver economy increases markedly.Based on these findings,we recommend that policy efforts focus on advancing high-quality population development in a differentiated manner,accelerating digital technological innovation,expanding educational resources for older adults,and promoting human capital upgrading,thereby enhancing its role in fostering the silver economy. 展开更多
关键词 high-quality population development silver economy digital technological innovation population aging human capital structure upgrading
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Evaluating the safety and diagnostic performance of endoscopic ultrasound-guided fine-needle biopsy in the geriatric population 认领 引用
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作者 Zahabia Sohail Aisha Jamal +5 位作者 Masood Muhammad Karim Syedda Ayesha Abdul Hadi Shahid Muhammad Bazil Musharraf Zeeshan Uddin Adeel Ur Rehman 《World Journal of Gastrointestinal Endoscopy》 2026年第1期110-118,共9页
BACKGROUND Endoscopic ultrasound(EUS)has emerged as a key diagnostic and therapeutic modality due to its minimally invasive nature and high success rates.It is widely used for diagnosing and staging gastrointestinal(G... BACKGROUND Endoscopic ultrasound(EUS)has emerged as a key diagnostic and therapeutic modality due to its minimally invasive nature and high success rates.It is widely used for diagnosing and staging gastrointestinal(GI),pancreatobiliary,and lung malignancies.EUS-guided fine needle biopsy(EUS-FNB)provides preserved tissue architecture,improving histological diagnosis for such conditions.The elderly are at significantly higher risk of GI lesions,being ten times more prone to malignancy and experiencing higher mortality,thereby requiring safer and less invasive diagnostic approaches.Despite its increasing use,evidence on EUS-FNB safety and diagnostic yield in geriatric population,particularly from resourcelimited settings,remains limited.AIM To assess the indications,diagnostic efficacy,and safety profile of EUS-FNB in the geriatric population.METHODS This single-centre retrospective study included patients aged 65 years or above who underwent EUS-guided biopsy between June 2020 and June 2022 at Aga Khan University Hospital,a tertiary care centre in Karachi,Pakistan.Patient demographics,procedural details including lesion site,number of needle passes,needle type,and tissue acquisition technique,along with histopathological diagnosis,were extracted from medical records.Data were analysed using SPSS,with categorical variables reported as frequencies and percentages,and continuous variables as mean±SD.RESULTS A total of 67 elderly patients were included,with a mean age of 72.7±6.33 years;most were male(72%).The median duration of the EUS procedure was 19(23)minutes.Most patients underwent biopsy for pancreatic lesions(40.3%),followed by mediastinal(16.4%)and gallbladder/common bile duct lesions(13.4%).In 31.4%cases,the specimen was obtained with 2 needle passes,while 41.4%required 1 pass and 22.9%required 3 passes.Multitargeted biopsies using a single pass were performed in 7.5%cases.A Franseen-design needle was used in all cases,with 22G utilized in 92.5%and 25G in 7.5%.Diagnostic adequacy was 100%,with no procedure-related complications.Histopathology revealed pancreatic cancer(34.3%),benign lesions(28.4%),and metastatic renal carcinoma(6%).CONCLUSION EUS-FNB is an effective minimally invasive diagnostic tool in elderly,demonstrating high diagnostic adequacy without complications.Future studies are warranted to further validate its safety and effectiveness in this population. 展开更多
关键词 Endosonography Endoscopic ultrasound-guided fine needle biopsy Aged Geriatric population Malignancy Diagnostic yield Minimally invasive diagnosis Procedural safety and low-and middle-income countries
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Solid fuel use and heart disease in middle-aged and older Chinese populations:a prospective cohort study 认领 引用
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作者 Jun-Wen WANG Ke-Xin CHEN +8 位作者 Teng HU Yu-Yang YE Yi-Fei ZHAO Xin-Ru HU Jiang YU Simayi Abulikemu Mai-Lin WEI Jun MA Yong PENG 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2026年第2期100-112,共13页
BACKGROUND Solid fuel use for cooking and heating is a major environmental risk factor,yet its association with new-onset heart disease(HD)remains unclear.The aim of this study was to investigate the relationship betw... BACKGROUND Solid fuel use for cooking and heating is a major environmental risk factor,yet its association with new-onset heart disease(HD)remains unclear.The aim of this study was to investigate the relationship between solid fuel exposure and new-onset HD in a large cohort.METHODS Multivariable logistic regression models assessed associations between cooking/heating fuel types(coal,crop residue/wood,liquefied petroleum gas,natural gas,and others)and new-onset HD.Subgroup analyses explored effect modification by age,sex,education,smoking,alcohol use,and region.RESULTS A prospective cohort study included 5915 participants,with 781 participants(13.2%)developing new-onset HD.Coal use for cooking showed an initial association with new-onset HD risk(OR=1.41,95%CI:1.06–1.86,P=0.02),which attenuated after full adjustment(OR=1.28,95%CI:0.96–1.72,P=0.10).Coal use for heating demonstrated robust associations across all models(OR=1.86,95%CI:1.42–2.43,P<0.001).Crop residue/wood burning for heating was also significant(Model 2:OR=1.40,95%CI:1.06–1.86,P=0.02).Subgroup analyses revealed stronger associations among females,non-smokers,non-drinkers,and less-educated participants.Geographic stratification showed significant associations in southern but not northern regions.CONCLUSIONS Solid fuel use,particularly coal for heating,is associated with increased new-onset HD risk.Reducing solid fuel exposure is crucial for HD prevention in low-resource settings. 展开更多
关键词 petroleum gasnatural gasand solid fuel multivariable logistic regression models older populations middle aged heart disease prospective cohort study effect modificatio
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Ignoring population differences in minimum mortality temperature substantially underestimates heat exposure and risk 认领 引用
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作者 Jie Cao Weiqi Zhou Zheng Cao 《Ecological Frontiers》 CSCD 2026年第1期135-144,共10页
Urban populations are increasingly exposed to extreme heat due to climate change and rapid urbanization,heightening health risks in cities worldwide.Accurate heat exposure assessment is essential for public health pla... Urban populations are increasingly exposed to extreme heat due to climate change and rapid urbanization,heightening health risks in cities worldwide.Accurate heat exposure assessment is essential for public health planning and risk reduction.Most existing approaches rely on a single threshold temperature(e.g.,35℃of daily max temperature),applied uniformly to the entire population.However,this one-size-fits-all assumption overlooks substantial differences in heat sensitivity across population subgroups.In this study,we address this limitation by quantifying subgroup-specific temperature-mortality relationships and using corresponding minimum mortality temperatures(MMTs)to assess heat exposure.Results show that the population-wide MMT was 27.5℃,but it varied greatly across population subgroups.The elderly population(≥65)had an MMT of 24.6℃,much lower than the 28.6℃observed in younger individuals(<65).Females also exhibited a lower MMT that males(25℃versus 28.2℃).However,educational attainment did not significantly affect MMT.Using a uniform MMT resulted in substantial underestimation of heat exposure,ranging from 25.3%in 1990 to 13.9%in 2020,reflecting demographic shifts over time.Spatially,nearly half of the city experienced underestimated heat risk,especially in central and northeastern regions where heat-vulnerable populations are concentrated.These findings underscore the need for more nuanced heat exposure assessments that account for demographic and spatial variability,paving the way for targeted public health interventions to protect the most vulnerable urban populations. 展开更多
关键词 Heat exposure Heat risk Population difference Minimum mortality temperature Mortality burden
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Qualitative Analysis and Numerical Simulation of a Predator-Prey Model for Invertebrate Predators in Aquatic Population Ecosystem 认领 引用
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作者 WANG Lijuan JIANG Hongling +3 位作者 HE Jinchan ZHAO Qi JING Miaomiao ZHAO Jihong 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2026年第2期101-111,共11页
The predation mechanism of invertebrates(e.g.,Tortanus dextrilobatus)on plankton in aquatic population ecosystem is a significant research topic.In this paper,the interaction between invertebrates and plankton is simu... The predation mechanism of invertebrates(e.g.,Tortanus dextrilobatus)on plankton in aquatic population ecosystem is a significant research topic.In this paper,the interaction between invertebrates and plankton is simulated by a modified Leslie-Gower predator-prey model.Using the theory of reaction-diffusion equations,a priori estimate,existence,uniqueness and stability conditions of the positive steady state solution are established.Furthermore,numerical simulations are conducted to quantitatively analyze the dynamical behavior.The research shows that as long as the Allee effect constant satisfies the appropriate relationship and the growth rates of predator and prey are appropriately large,the predator and prey can not only coexist,but also the coexistence mode is unique and stable under low predation-rate.In addition,the numerical simulations show that the coexistence may be stable under high predation-rate.Meanwhile,with the increase of predation rate,the population density of predators will decrease. 展开更多
关键词 predator-prey model aquatic population ecosystem Allee effect Ivlev functional response positive steady-state solutions numerical simulation
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