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Spatial-temporal heterogeneity and controlling factors of evapotranspiration in Nujiang River Basin based on Variable Infiltration Capacity(VIC)model
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作者 ZHANG Xianhe LIU Shiyin +1 位作者 ZHU Yu XIE Fuming 《Journal of Mountain Science》 SCIE CSCD 2024年第11期3598-3614,共17页
Land surface evapotranspiration(ET)is a critical component in the hydrological cycle but has not well been understood in data-scarce areas especially in river basins,like Nujiang River(NRB)which is characterized by la... Land surface evapotranspiration(ET)is a critical component in the hydrological cycle but has not well been understood in data-scarce areas especially in river basins,like Nujiang River(NRB)which is characterized by large elevation gradient and different vegetation zones with complex processes of water and energy exchange.The quality of ET from optical remote sensing is constrained by cloud cover which is common in the NRB in the monsoon seasons.To understand factors controlling the spatial-temporal heterogeneity of ET in NRB,we employed the Variable Infiltration Capacity(VIC)hydrological model by parameter optimization with support of quality controlled remote sensing ET product and observed river runoff series in the river.The modeled ET has increased during 1984-2018,which might be one of the reasons for the runoff decrease but precipitation increase in the same period.ET increase and runoff decrease tended to be quicker within altitudinal band of 2000-4000 m than in other areas in NRB.We observed that ET variation in different climatic zones were controlled by different factors.ET is generally positively correlated with precipitation,temperature,and shortwave radiation but negatively with relative humidity.In the Tundra Climate(Et)zone in the upper reach of NRB,ET is controlled by precipitation,while it is controlled by shortwave radiation in the snow climate with dry winter(Dw)zone.ET increase is influenced by the increase of temperature,wind speed,and shortwave radiation in the middle and downstream of NRB with warm temperate climate,fully humid(Cf)and warm temperate climate with dry winter(Cw). 展开更多
关键词 EVAPOTRANSPIRATION Variable infiltration capacity(VIC)model Spatial temporal heterogeneity Climate change Controlling factors Nujiang River Basin
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Spatial-temporal Heterogeneity of Green Development Efficiency and Its Influencing Factors in Growing Metropolitan Area: A Case Study for the Xuzhou Metropolitan Area 被引量:8
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作者 QIU Fangdao CHEN Yang +3 位作者 TAN Juntao LIU Jibin ZHENG Ziyan ZHANG Xinlin 《Chinese Geographical Science》 SCIE CSCD 2020年第2期352-365,共14页
This study analyzed the spatial-temporal heterogeneity of green development efficiency and its influencing factors in the growing Xuzhou Metropolitan Area for the period 2000–2015.The slacks-based measure(SBM)model,s... This study analyzed the spatial-temporal heterogeneity of green development efficiency and its influencing factors in the growing Xuzhou Metropolitan Area for the period 2000–2015.The slacks-based measure(SBM)model,spatial autocorrelation,and the geographically weighted regression(GWR)model were used to conduct the analysis.The conclusions were as follows:first,the overall efficiency of green development of the Xuzhou Metropolitan Area decreased,the regional differences and spatial agglomeration shrunk and differences within the region were the main contributors to the regional differences of green development efficiency.Second,the counties with high-efficiency green development were distributed along the coast,and along the routes of the Beijing-Shanghai and the Eastern Longhai railways.A developing axis of the high-efficiency counties was the main feature of the spatial pattern for green development efficiency.Third,regarding spatial correlation and green development efficiency,the High-High type counties in the Xuzhou Metropolitan Area formed a centralized distribution corridor along the inter-provincial border areas of Henan and Jiangsu,whereas the Low-Low type counties were concentrated in the external,marginal parts of the metropolitan area.Fourth,the major factors(ranked in decreasing order of impact)influencing green development efficiency were innovation,government regulations,the economic development level,energy consumption,and industrial structure.These factors exerted their influence to varying extents;the influence of the same factor had different effects in different regions and obvious spatial differences were observed for the different regions. 展开更多
关键词 GROWING METROPOLITAN area green development EFFICIENCY spatial and TEMPORAL heterogeneity influential factors XUZHOU METROPOLITAN Area China
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Spatial-temporal Heterogeneity of Industrial Structure Transformation and Carbon Emission Effects in Xuzhou Metropolitan Area 被引量:3
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作者 QIU Fangdao YUAN He +1 位作者 BAI Liangyu LI Fei 《Chinese Geographical Science》 SCIE CSCD 2017年第6期904-917,共14页
Employing decoupling index and industrial structure characteristic bias index methods, this study analyzed the spatial-temporal characteristics of industrial structure transformations and their resulting carbon emissi... Employing decoupling index and industrial structure characteristic bias index methods, this study analyzed the spatial-temporal characteristics of industrial structure transformations and their resulting carbon emissions in the Xuzhou Metropolitan Area from 2000 to 2014, with a focus on their relationships and driving factors. Our research indicates that carbon emission intensity from industrial structures in the Xuzhou Metropolitan Area at first showed an increasing trend, which then decreased. Furthermore, the relationship between emissions and industrial economic growth has been trending toward absolute decoupling. From the perspective of the center-periphery, the Xuzhou Metropolitan Area formed a concentric pattern, where both progress towards low emissions and the level of technological advancement gradually diminished from the center to the periphery. In terms of variation across provinces, the ISCB index in the eastern Henan has decreased the slowest, followed by the southern Shandong and the northern Anhui, with the northern Jiangsu ranking last. During this period, resource-and labor-intensive industries were the primary growth industries in the northern Anhui and the eastern Henan, while labor-intensive industries dominated the southern Shandong and capital-intensive industries dominated the northern Jiangsu. In terms of city types, the spatial pattern for industrial structure indicates that recession resource-based cities had higher carbon emission intensities than mature resource-based cities, followed by non-resource-based cities and regenerative resource-based cities. Generally, the industrial structure in the Xuzhou Metropolitan Area has transformed from being resource-intensive to capital-intensive, and has been trending toward technology-intensive as resource availability has been exploited to exhaustion and then been regenerated. Industrial structure has been the leading factor causing heterogeneity of carbon emission intensities between metropolitan cities. Therefore, the key to optimizing the industrial structure and layout of metropolitan areas is to promote industrial structure transformation and improve the system controlling collaborative industrial development between cities. 展开更多
关键词 industrial structure transformation industrial structure characteristic bias carbon emission effect spatial-temporal pattern Xuzhou Metropolitan Area
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Spatial-temporal distribution and emission of urban scale air pollutants in Hefei based on Mobile-DOAS 被引量:1
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作者 Zhidong Zhang Pinhua Xie +8 位作者 Ang Li Min Qin Jin Xu Zhaokun Hu Xin Tian Feng Hu Yinsheng Lv Jiangyi Zheng Youtao Li 《Journal of Environmental Sciences》 2025年第5期238-251,共14页
As a significant city in the Yangtze River Delta regions,Hefei has experienced rapid changes in the sources of air pollution due to its high-speed economic development and urban expansion.However,there has been limite... As a significant city in the Yangtze River Delta regions,Hefei has experienced rapid changes in the sources of air pollution due to its high-speed economic development and urban expansion.However,there has been limited research in recent years on the spatial-temporal distribution and emission of its atmospheric pollutants.To address this,this study conducted mobile observations of urban roads using the Mobile-DOAS instrument from June 2021 to May 2022.The monitoring results exhibit a favourable consistent with TROPOMI satellite data and ground monitoring station data.Temporally,there were pronounced seasonal variations in air pollutants.Spatially,high concentration of HCHO and NO_(2)were closely associated with traffic congestion on roadways,while heightened SO_(2)levels were attributed to winter heating and industrial emissions.The study also revealed that with the implementation of road policies,the average vehicle speed increased by 95.4%,while the NO concentration decreased by 54.4%.In the estimation of urban NO_(x)emission flux,it was observed that in temporal terms,compared with inventory data,the emissions calculated viamobile measurements exhibitedmore distinct seasonal patterns,with the highest emission rate of 349 g/sec in winter and the lowest of 142 g/sec in summer.In spatial terms,the significant difference in emissions between the inner and outer ring roads also suggests the presence of the city’s primary NO_(x)emission sources in the area between these two rings.This study offers data support for formulating the next phase of air pollution control measures in urban areas. 展开更多
关键词 Mobile-DOAS HCHO NO_(2) SO_(2) spatial-temporal distribution NOx emission
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A Framework for Analyzing Spatial Heterogeneity and Influencing Factors of Campus Green Space in Xi’an,China 被引量:2
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作者 ZANG Zexuan ZHANG Liwei +5 位作者 LIU Yu YANG Xiping WANG Zhuangzhuang JIAO Lei WANG Hao LUO Ying 《Chinese Geographical Science》 2025年第4期786-801,共16页
Increased exposure to campus green spaces can make a positive contribution to the healthy development of students.However,understanding of the current supply of campus green space(CGS)and its drivers at different educ... Increased exposure to campus green spaces can make a positive contribution to the healthy development of students.However,understanding of the current supply of campus green space(CGS)and its drivers at different education stages is still limited.A new framework was established to evaluate the spatial heterogeneity and its influencing factors across all education stages(kindergarten,primary school,middle school,college)in 1100 schools at the urban scale of Xi’an,China.The research results show that:1)CGS is lower in the Baqiao district and higher in the Yanta and Xincheng districts of Xi’an City.‘Green wealthy schools are mainly concentrated in the Weiyang,Chang’an and Yanta districts.2)CGS of these schools in descending order is college(31.40%)>kindergarten(18.32%)>middle school(13.56%)>primary school(10.70%).3)Colleges have the most recreation sites(n(number)=2),the best education levels(11.93 yr),and the lowest housing prices(1.18×10^(4) yuan(RMB)/m^(2));middle schools have the highest public expenditures(3.97×10^(9) yuan/yr);primary schools have the highest CGS accessibility(travel time gap(TTG)=31.33).4)Multiscale Geographically Weighted Regression model and Spearman’s test prove that recreation sites have a significant positive impact on college green spaces(0.28–0.35),and education level has a significant positive impact on kindergarten green spaces(0.16–0.24).This research framework provides important insights for the assessment of school greening initiatives aimed at fostering healthier learning environments for future generations. 展开更多
关键词 campus green space(CGS) spatial heterogeneity multiscale geographically weighted regression Xi’an China
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The implications of single-cell RNA-seq analysis in prostate cancer:unraveling tumor heterogeneity,therapeutic implications and pathways towards personalized therapy 被引量:1
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作者 De-Chao Feng Wei-Zhen Zhu +8 位作者 Jie Wang Deng-Xiong Li Xu Shi Qiao Xiong Jia You Ping Han Shi Qiu Qiang Wei Lu Yang 《Military Medical Research》 2025年第2期220-241,共22页
In recent years,advancements in single-cell and spatial transcriptomics,which are highly regarded developments in the current era,particularly the emerging integration of single-cell and spatiotemporal transcriptomics... In recent years,advancements in single-cell and spatial transcriptomics,which are highly regarded developments in the current era,particularly the emerging integration of single-cell and spatiotemporal transcriptomics,have enabled a detailed molecular comprehension of the complex regulation of cell fate.The insights obtained from these methodologies are anticipated to significantly contribute to the development of personalized medicine.Currently,single-cell technology is less frequently utilized for prostate cancer compared with other types of tumors.Start-ing from the perspective of RNA sequencing technology,this review outlined the signifcance of single-cell RNA sequencing(scRNA-seq)in prostate cancer research,encompassing preclinical medicine and clinical applications.We summarize the differences between mouse and human prostate cancer as revealed by scRNA-seq studies,as well as a combination of multi-omics methods involving scRNA-seq to highlight the key molecular targets for the diagnosis,treatment,and drug resistance characteristics of prostate cancer.These studies are expected to provide novel insights for the development of immunotherapy and other innovative treatment strategies for castration-resistant prostate cancer.Furthermore,we explore the potential clinical applications stemming from other single-cell technologies in this review,paving the way for future research in precision medicine. 展开更多
关键词 Prostate cancer Single-cell RNA sequencing(scRNA-seq) Tumor microenvironment Tumor heterogeneity Treatment resistance Precision medicine
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Heterogeneity of mature oligodendrocytes in the central nervous system
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作者 Chao Weng Adam M.R.Groh +4 位作者 Moein Yaqubi Qiao-Ling Cui Jo Anne Stratton G.R.Wayne Moore Jack P.Antel 《Neural Regeneration Research》 SCIE CAS 2025年第5期1336-1349,共14页
Mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous system.Recent evidence has challenged the classical view of the functio... Mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous system.Recent evidence has challenged the classical view of the functionally static mature oligodendrocyte and revealed a gamut of dynamic functions such as the ability to modulate neuronal circuitry and provide metabolic support to axons.Despite the recognition of potential heterogeneity in mature oligodendrocyte function,a comprehensive summary of mature oligodendrocyte diversity is lacking.We delve into early 20th-century studies by Robertson and Río-Hortega that laid the foundation for the modern identification of regional and morphological heterogeneity in mature oligodendrocytes.Indeed,recent morphologic and functional studies call into question the long-assumed homogeneity of mature oligodendrocyte function through the identification of distinct subtypes with varying myelination preferences.Furthermore,modern molecular investigations,employing techniques such as single cell/nucleus RNA sequencing,consistently unveil at least six mature oligodendrocyte subpopulations in the human central nervous system that are highly transcriptomically diverse and vary with central nervous system region.Age and disease related mature oligodendrocyte variation denotes the impact of pathological conditions such as multiple sclerosis,Alzheimer's disease,and psychiatric disorders.Nevertheless,caution is warranted when subclassifying mature oligodendrocytes because of the simplification needed to make conclusions about cell identity from temporally confined investigations.Future studies leveraging advanced techniques like spatial transcriptomics and single-cell proteomics promise a more nuanced understanding of mature oligodendrocyte heterogeneity.Such research avenues that precisely evaluate mature oligodendrocyte heterogeneity with care to understand the mitigating influence of species,sex,central nervous system region,age,and disease,hold promise for the development of therapeutic interventions targeting varied central nervous system pathology. 展开更多
关键词 aging central nervous system diseases electron microscopy heterogeneity immunohistochemistry myelin sheath natural history NEUROGLIA OLIGODENDROGLIA single-cell gene expression analysis
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Controlling update distance and enhancing fair trainable prototypes in federated learning under data and model heterogeneity
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作者 Kangning Yin Zhen Ding +1 位作者 Xinhui Ji Zhiguo Wang 《Defence Technology(防务技术)》 2025年第5期15-31,共17页
Heterogeneous federated learning(HtFL)has gained significant attention due to its ability to accommodate diverse models and data from distributed combat units.The prototype-based HtFL methods were proposed to reduce t... Heterogeneous federated learning(HtFL)has gained significant attention due to its ability to accommodate diverse models and data from distributed combat units.The prototype-based HtFL methods were proposed to reduce the high communication cost of transmitting model parameters.These methods allow for the sharing of only class representatives between heterogeneous clients while maintaining privacy.However,existing prototype learning approaches fail to take the data distribution of clients into consideration,which results in suboptimal global prototype learning and insufficient client model personalization capabilities.To address these issues,we propose a fair trainable prototype federated learning(FedFTP)algorithm,which employs a fair sampling training prototype(FSTP)mechanism and a hyperbolic space constraints(HSC)mechanism to enhance the fairness and effectiveness of prototype learning on the server in heterogeneous environments.Furthermore,a local prototype stable update(LPSU)mechanism is proposed as a means of maintaining personalization while promoting global consistency,based on contrastive learning.Comprehensive experimental results demonstrate that FedFTP achieves state-of-the-art performance in HtFL scenarios. 展开更多
关键词 heterogeneous federated learning Model heterogeneity Data heterogeneity Contrastive learning
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Spatial-Temporal Coupling and Determinants of Digital Economy and High-Quality Development: Insights from the Yellow River Region
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作者 Zhang Shu Wang Kangqing Guo Jinlong 《全球城市研究(中英文)》 2025年第2期1-17,149,共18页
In the current situation of decelerating economic expansion,examining the digital economy(DE)as a novel economic model is beneficial for the local economy’s sustainable and high-quality development(HQD).We analyzed p... In the current situation of decelerating economic expansion,examining the digital economy(DE)as a novel economic model is beneficial for the local economy’s sustainable and high-quality development(HQD).We analyzed panel data from the Yellow River(YR)region from 2013 to 2021 and discovered notable spatial variances in the composite index and coupling coordination of the two systems.Specifically,the downstream region exhibited the highest coupling coordination,while the upstream region had the lowest.We identified that favorable factors such as economic development,innovation,industrial upgrading,and government intervention can bolster the coupling.Our findings provide a valuable framework for promoting DE and HQD in the YR region. 展开更多
关键词 High-quality development Digital economy spatial-temporal coupling the Yellow River region
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MSSTGCN: Multi-Head Self-Attention and Spatial-Temporal Graph Convolutional Network for Multi-Scale Traffic Flow Prediction
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作者 Xinlu Zong Fan Yu +1 位作者 Zhen Chen Xue Xia 《Computers, Materials & Continua》 2025年第2期3517-3537,共21页
Accurate traffic flow prediction has a profound impact on modern traffic management. Traffic flow has complex spatial-temporal correlations and periodicity, which poses difficulties for precise prediction. To address ... Accurate traffic flow prediction has a profound impact on modern traffic management. Traffic flow has complex spatial-temporal correlations and periodicity, which poses difficulties for precise prediction. To address this problem, a Multi-head Self-attention and Spatial-Temporal Graph Convolutional Network (MSSTGCN) for multiscale traffic flow prediction is proposed. Firstly, to capture the hidden traffic periodicity of traffic flow, traffic flow is divided into three kinds of periods, including hourly, daily, and weekly data. Secondly, a graph attention residual layer is constructed to learn the global spatial features across regions. Local spatial-temporal dependence is captured by using a T-GCN module. Thirdly, a transformer layer is introduced to learn the long-term dependence in time. A position embedding mechanism is introduced to label position information for all traffic sequences. Thus, this multi-head self-attention mechanism can recognize the sequence order and allocate weights for different time nodes. Experimental results on four real-world datasets show that the MSSTGCN performs better than the baseline methods and can be successfully adapted to traffic prediction tasks. 展开更多
关键词 Graph convolutional network traffic flow prediction multi-scale traffic flow spatial-temporal model
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Impact of Permeability Heterogeneity on Methane Hydrate Production Behavior during Depressurization with Controlled Sand Production
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作者 Junyu Deng Rui Zhang +4 位作者 Xudong Zhao Hongzhi Xu Peng Ji Zizhen Zhang Yifan Yang 《Energy Engineering》 2025年第10期4153-4168,共16页
Field tests have demonstrated that depressurization with controlled sand production is an effective technique for natural gas hydrate extraction.Variations in depositional environments and processes result in signific... Field tests have demonstrated that depressurization with controlled sand production is an effective technique for natural gas hydrate extraction.Variations in depositional environments and processes result in significant heterogeneity within subsea natural gas hydrate-bearing sediments.However,the influence of permeability heterogeneity on production performance during depressurization with controlled sand production remains inadequately understood.In this study,a multiphase,multi-component mathematical model is developed to simulate depressurization with controlled sand production in methane hydrate-bearing sediments,incorporating geological conditions representative of unconsolidated argillaceous siltstone hydrate deposits in the Shenhu area of the South China Sea.The effects of permeability heterogeneity-specifically,horizontal autocorrelation length and global permeability heterogeneity-on production performance during depressurization with sand production are investigated using geostatistical modeling combined with finite difference method based numerical simulations.Results show that as the horizontal autocorrelation length of permeability distribution increases,cumulative gas production first rises and then declines,reaching its peak at λ_(Dh)=0.1,whereas sand production steadily increases.In addition,higher formation permeability heterogeneity results in increased cumulative gas and sand production,suggesting that greater heterogeneity promotesmethane hydrate decomposition and gas recovery.These findings can offer valuable insights for optimizing future field development of hydrate-bearing sediments by depressurization with controlled sand production. 展开更多
关键词 Methane hydrate heterogeneity DEPRESSURIZATION PRODUCTIVITY sand production
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Understanding the effect of heterogeneity on amendment delivery in fractured low-permeability soils
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作者 Mengwen Gao He Chen +2 位作者 Shijin Feng Qiteng Zheng Hongxin Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第8期5188-5205,共18页
Due to severe mass transfer limitations,the remediation efficiency of low-permeability contaminated sites often fails to meet expectations.Hydraulic fracturing technology has been utilized to enhance amendment deliver... Due to severe mass transfer limitations,the remediation efficiency of low-permeability contaminated sites often fails to meet expectations.Hydraulic fracturing technology has been utilized to enhance amendment delivery,but the influence of soil heterogeneity is commonly overlooked.To address this issue,this study develops a numerical model to simulate the enhanced transport of amendments,incorporating convection,diffusion,adsorption,and degradation processes.Within the model,random permeability fields are generated based on geostatistical methods to explore how soil heterogeneity affects amendment injection efficiency,distribution characteristics,and the underlying physical mechanisms.The results indicate that(1)soil heterogeneity significantly reduces the amendment injection efficiency,with stronger heterogeneity correlating to lower efficiency,(2)soil heterogeneity markedly alters the amendment distribution characteristics,leading to the formation of localized“nodes”,(3)the mechanism by which heterogeneity reduces injection efficiency involves decreasing the density of preferential flow paths in the soil,and(4)the adverse effects of heterogeneity can be mitigated by employing pressure compensation or adjusting well spacing. 展开更多
关键词 heterogeneity Low-permeability soil Hydraulic fracturing Fracture-matrix system REMEDIATION
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Resolving the spatial and cellular architecture of intra-tumor heterogeneity by multi-region dissection of lung adenocarcinoma
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作者 Song Mei Xiaolei Wang +12 位作者 Mengmeng Zhao Qing Huang Yixuan Huang Mingming Su Xinlei Zhang Xu Wang Xueyu Hao Tianning Wang Yanhua Wu Yuanhui Ma Jingnan Wang Peng Zhang Yan Zheng 《Journal of Genetics and Genomics》 2025年第9期1121-1132,共12页
Although the spatial characteristics within the tumor microenvironment of lung adenocarcinoma(LUAD)have been identified,the mechanisms by which these factors promote LUAD progression and immune evasion remain unclear.... Although the spatial characteristics within the tumor microenvironment of lung adenocarcinoma(LUAD)have been identified,the mechanisms by which these factors promote LUAD progression and immune evasion remain unclear.Using spatial transcriptomics and single-cell RNA-sequencing data from multi-regional LUAD biopsies consisting of tumor core,tumor edge,and normal area,we sought to delineate the spatial heterogeneity and driving factors of cell colocalization.Two cancer cell sub-clusters(Cancer_c1 and Cancer_c2),associated with LUAD initiation and metastasis,respectively,exhibit distinct spatial distributions and immune cell colocalizations.In particular,Cancer_c1,enriched within the tumor core,could directly interact with B cells or indirectly recruit B cells through macrophages.Conversely,Cancer_c2 enriched within the tumor edge exhibits colocalization with CD8^(+)T cells.Collectively,our work elucidates the spatial distribution of cancer cell subtypes and their interaction with immune cells in the core and edge of LUAD,providing insights for developing therapeutic strategies for cancer intervention. 展开更多
关键词 Lung adenocarcinoma Spatial transcriptomics ScRNA-Seq Intra-tumoral heterogeneity Cell colocalizations
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Synergistic deformation of bimodal-structured AZ80 Mg alloy for excellent strength-ductility synergy via regulating the heterogeneity level
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作者 Guofeng Liu Runxia Li +2 位作者 Biao Wang Zhenmin Wang Hongfei Zhang 《Journal of Magnesium and Alloys》 2025年第8期3964-3985,共22页
The trade-off between strength and ductility has long been a challenge for Mg alloy.To address this issue,bimodal-structured AZ80 Mg alloys with varying heterogeneity levels were fabricated via low-temperature extrusi... The trade-off between strength and ductility has long been a challenge for Mg alloy.To address this issue,bimodal-structured AZ80 Mg alloys with varying heterogeneity levels were fabricated via low-temperature extrusion in this work.The results reveal the microstructure comprising second-phase particle(SP_(p),β-Mg_(17)Al_(12)and Mg_(3) Mn_(2) Al_(18))-reinforced fine grains(FGs)FGs and SP_(p)-free coarse grains(CGs),with the heterogeneity level decreasing as extrusion temperature increases.As the heterogeneity level decreases,the synergistic deformation capacity initially improves,reaching a maximum at the moderate heterogeneity level of 0.31 GPa and 0.238,and then declines.This exceptional capacity is attributed to the hetero-deformation induced(HDI)stress,which effectively alleviates the strain gradients by activating〈c+a〉dislocations and non-basal〈a〉dislocations during deformation.An optimal combination of 287 MPa in yield strength,393 MPa in ultimate tensile strength,and 14.96%in elongation is achieved in the alloy with a moderate heterogeneity level.The excellent strength-ductility synergy originates from the enhanced capacity of dislocations accumulation driven by remarkable capacity of synergistic deformation and the synergistic strengthening mechanisms.This work provides a new insight into the design of bimodal structure to produce high-performance Mg alloys. 展开更多
关键词 Mg alloy heterogeneity level Synergistic deformation Strength and ductility
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Synergistic effect of bonding heterogeneity and phonon localization in introducing excellent thermoelectric properties in layered heteroanionic NdZnSbO material
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作者 Da Wan Shuwei Tang +4 位作者 Shulin Bai Xiaodong Li Peng Ai Wanrong Guo Tuo Zheng 《Journal of Energy Chemistry》 2025年第1期259-272,共14页
Layered rare-earth metal oxides,harnessing the dual properties of oxides and two-dimensional layered materials,exhibit remarkable thermal stability and quantum confinement effects.Therefore,this work adopts the first-... Layered rare-earth metal oxides,harnessing the dual properties of oxides and two-dimensional layered materials,exhibit remarkable thermal stability and quantum confinement effects.Therefore,this work adopts the first-principles calculation combined with the Boltzmann transport theory to predict the thermoelectric properties of NdZnSbO compound.The coexistence of weak interlayer van der Waals interactions,robust intralayer ionic bonding,and partial covalent bonding leads to remarkable bonding heterogeneity,which engenders pronounced phonon scattering and imposes constraints on thermal transport along the out-of-plane direction.The weakened chemical bonds induced by the antibonding states,together with the rattling-like behavior of the Zn atom,culminate in the profound anharmonicity in the layered NdZnSbO compound.The weakening bond and heavy element contribute to the softness of phonon modes,which significantly diminishes the phonon group velocity.The redistribution-dominated four-phonon scattering process spans a large optical gap,which effectively reduces the lattice thermal conductivity.The NdZnSbO compound exhibits direct semiconductor characteristic with a bandgap of 0.73 e V by adopting the Heyd-Scuseria-Ernzerhof(HSE06)functional in combination with spin–orbit coupling(SOC)effect.The multi-valley feature of NdZnSbO compound augur favorably for band degeneracy,thus amplifying the power factor.Consequently,an optimal figure-of-merit(ZT)of 3.40 at 900 K is achieved for the n-type NdZnSbO compound.The present study delves deeply insights into the origins for the low thermal conductivity of NdZnSbO compound and proposes an optimization scheme to enhance overall thermoelectric performance. 展开更多
关键词 Heteroanionic materials Multi-valley characteristics Four-phonon scattering Bonding heterogeneity Rattling-like behavior
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Abundant and rare subcommunity assemblages of prokaryotes and eukaryotes controlled by vertical environmental heterogeneity in an urban reservoir
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作者 Xun Wang Huai-yu Cao +7 位作者 Jia-wen Gan Tang Liu Pei-fang Wang Qiu-sheng Yuan Xiao-lei Xing Cheng-gong Du Yu-ran Zheng Yun-xin Liu 《Water Science and Engineering》 2025年第3期312-323,共12页
Reservoirs play a critical role in addressing water resources challenges.However,their vertical influence on the assembly mechanisms of different microbial communities,including prokaryotes and eukaryotes,remains uncl... Reservoirs play a critical role in addressing water resources challenges.However,their vertical influence on the assembly mechanisms of different microbial communities,including prokaryotes and eukaryotes,remains unclear.This study examined the vertical diversity patterns of abundant and rare subcommunities of prokaryotes and eukaryotes in an urban reservoir,using water depth as a geographical gradient and employing high-throughput sequencing.The impact of vertical environmental heterogeneity on community structure was quantified,and key drivers of these dynamics were identified.The results indicated that the urban reservoir exhibited statistically significant differences in the vertical distribution of water temperature and oxidation/reduction potential.The a-diversity of the abundant subcommunity displayed an opposing vertical pattern compared to that of the rare subcommunity,while the b-diversity for both subcommunities of prokaryotes and eukaryotes increased with water depth.Moreover,the distinct diversity patterns of abundant and rare subcommunities were associated with environmental heterogeneity and species adaptability.Notably,the b-diversity of the rare subcommunity of eukaryotes was primarily driven by species turnover in surface water,whereas nestedness became the dominant factor in deeper water.Furthermore,eukaryotic microbes exhibited a more pronounced response to changes in water depth than prokaryotes,consistent with the importance of heterogeneous selection to the eukaryotic community.Water temperature significantly affected the community composition of all groups,highlighting its importance in shaping community dynamics.This study provides valuable insights into the vertical distribution and assembly mechanisms of microbial communities in urban reservoirs,contributing to the protection and management of aquatic ecosystems under river regulation. 展开更多
关键词 Assembly process Vertical structure Environmental heterogeneity Rare biosphere Water temperature
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ESG rating and transformation upgrading of enterprises:An empirical test based on the heterogeneity of listed A-share enterprises
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作者 WEI Yu-xin LI Peng-yu +1 位作者 LI Yan CHEN Xi-meng 《Ecological Economy》 2025年第1期48-65,共18页
ESG(Environmental,Social,and Governance)performance has emerged as a central metric in assessing corporate sustainability.Utilizing ESG rating data for A-share listed companies on the Shanghai Stock Exchange spanning ... ESG(Environmental,Social,and Governance)performance has emerged as a central metric in assessing corporate sustainability.Utilizing ESG rating data for A-share listed companies on the Shanghai Stock Exchange spanning from 2019 to 2022,coupled with measures of corporate transformation and upgrading,this study introduces green innovation as a mediating variable to dissect the impact of ESG ratings on corporate transformation and upgrading.The key findings of this research are as follows:(1)ESG ratings positively influence corporate transformation and upgrading,a conclusion that retains robustness after a comprehensive series of tests and discussions on endogeneity.(2)Mechanism analysis reveals that ESG ratings foster corporate transformation and upgrading by enhancing corporate green innovation.(3)In comparison with other industries,the influence of ESG ratings on corporate transformation and upgrading is notably more pronounced among heavily polluting industries among listed companies in China.Additionally,ESG ratings exhibit a more significant promotional effect on non-state-owned enterprises compared to state-owned enterprises.Larger enterprises play a more substantial role in transformation and upgrading than small and medium-sized enterprises.The promotional effect of ESG ratings is more evident in enterprises with poor information disclosure quality.Furthermore,as media attention increases,so does the impact of ESG ratings on corporate transformation.This study offers valuable policy insights from the ESG rating perspective,aiming to propel corporate transformation and upgrading,thereby contributing to economic high-quality and sustainable development. 展开更多
关键词 ESG rating enterprise transformation and upgrading heterogeneity analysis
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Harnessing artificial intelligence to address immune response heterogeneity in low-dose radiation therapy
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作者 Jing-Qi Zeng Yi-Wei Gao Xiao-Bin Jia 《World Journal of Radiology》 2025年第5期1-4,共4页
Low-dose radiation therapy has emerged as a promising modality for cancer treatment because of its ability to stimulate antitumor immune responses while minimizing damage to healthy tissues.However,the significant het... Low-dose radiation therapy has emerged as a promising modality for cancer treatment because of its ability to stimulate antitumor immune responses while minimizing damage to healthy tissues.However,the significant heterogeneity in immune responses among patients complicates its clinical application,hindering outcome prediction and treatment personalization.Artificial intelligence(AI)offers a transformative solution by integrating multidimensional data such as immunomics,radiomics,and clinical features to decode complex immune pa-tterns and predict individual therapeutic outcomes.This editorial explored the potential of AI to address immune response heterogeneity in low-dose radiation therapy and proposed an AI-driven framework for precision immunotherapy.While promising,challenges,including data standardization,model interpre-tability,and clinical validation,must be overcome to ensure successful integration into oncological practice. 展开更多
关键词 Low-dose radiation Immune response heterogeneity Artificial intelligence Precision medicine IMMUNOTHERAPY Radiomics
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Research evaluation reform and the heterogeneity of researchers’metric-wiseness
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作者 Sandra Rousseau Cinzia Daraio 《Journal of Data and Information Science》 2025年第1期47-73,共27页
Purpose:We aimed to measure the variation in researchers’knowledge and attitudes towards bibliometric indicators.The focus is on mapping the heterogeneity of this metric-wiseness within and between disciplines.Design... Purpose:We aimed to measure the variation in researchers’knowledge and attitudes towards bibliometric indicators.The focus is on mapping the heterogeneity of this metric-wiseness within and between disciplines.Design/methodology/approach:An exploratory survey is administered to researchers at the Sapienza University of Rome,one of Europe’s oldest and largest generalist universities.To measure metric-wiseness,we use attitude statements that are evaluated by a 5-point Likert scale.Moreover,we analyze documents of recent initiatives on assessment reform to shed light on how researchers’heterogeneous attitudes regarding and knowledge of bibliometric indicators are taken into account.Findings:We found great heterogeneity in researchers’metric-wiseness across scientific disciplines.In addition,within each discipline,we observed both supporters and critics of bibliometric indicators.From the document analysis,we found no reference to individual heterogeneity concerning researchers’metric wiseness.Research limitations:We used a self-selected sample of researchers from one Italian university as an exploratory case.Further research is needed to check the generalizability of our findings.Practical implications:To gain sufficient support for research evaluation practices,it is key to consider researchers’diverse attitudes towards indicators.Originality/value:We contribute to the current debate on reforming research assessment by providing a novel empirical measurement of researchers’knowledge and attitudes towards bibliometric indicators and discussing the importance of the obtained results for improving current research evaluation systems. 展开更多
关键词 Research assessment Research reform Metric-Wiseness heterogeneity of researchers Bibliometric indicators Researchers attitudes
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Computed tomography-guided percutaneous biopsy for assessing tumor heterogeneity in neuroendocrine tumor metastases to the liver
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作者 Lei-Lei Ying Ke-Ning Li +2 位作者 Wen-Tao Li Xin-Hong He Chao Chen 《World Journal of Radiology》 2025年第5期35-44,共10页
BACKGROUND Gastroenteropancreatic neuroendocrine tumors(GEP-NETs)frequently metasta-size to the liver,with heterogeneity in tumor grade impacting patient prognosis and treatment.The Ki-67 index,a key prognostic marker... BACKGROUND Gastroenteropancreatic neuroendocrine tumors(GEP-NETs)frequently metasta-size to the liver,with heterogeneity in tumor grade impacting patient prognosis and treatment.The Ki-67 index,a key prognostic marker,often varies between primary and metastatic sites;however,routine liver biopsy remains controversial.Although percutaneous computed tomography-guided core needle biopsy(PCT-CNB)is safe and effective for focal lesions,its role in detecting intertumor grading discrepancies and survival implications in GEP-NETs is underexplored.Conflic-ting survival associations with grade shifts have been reported in previous stu-dies.We hypothesized that PCT-CNB could identify clinically significant grading heterogeneity in liver metastases,correlating with survival outcomes,thereby refining risk stratification and therapeutic strategies.METHODS We retrospectively investigated 92 patients with liver metastases from GEP-NETs via PCT-CNB,76 patient samples from the liver and primary sites,and 16 from the liver and secondary liver sites.Ki-67 immunohistochemistry was performed for tissue sampling,and grading classifications were determined.Intertumor grading classification heterogeneity and associated changes in patient survival outcomes were also evaluated.RESULTS No procedure-related mortality was recorded during or after biopsy.In 37/92 patients(40.2%),the grading classi-fications changed:The grading increased from G1 to G2 in 13 patients,from G1 to G3 in 2,and from G2 to G3 in 14;the grading decreased from G2 to G1 in 5 patients,from G3 to G1 in 1,and from G3 to G2 in 2.Patients with G1 or G2 disease had better progression-free survival and overall survival(OS)outcomes than those with G3 disease did(P=0.001 and P<0.001,respectively).The 5-year and 10-year OS rates for stable G2 patients were 67.5%and 26.0%,respectively,decreasing to 46.4%and 23.2%,respectively,among G2 patients whose grade increased(P=0.016).CONCLUSION The PCT-CNB of liver metastases from GEP-NETs differed in grade between the liver tumor and primary site/secondary liver metastases.Additionally,when grading increased from G2,the OS rate significantly de-creased. 展开更多
关键词 Image-guided core needle biopsy Gastroenteropancreatic neuroendocrine tumors Liver metastases SURVIVAL Tumor heterogeneity
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