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Spatial-temporal patterns of China's interprovincial migration, 1985-2010 被引量:7
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作者 LI Yang LIU Hui +2 位作者 TANG Qing LU Dadao XlAO Ningchuan 《Journal of Geographical Sciences》 SCIE CSCD 2014年第5期907-923,共17页
Migration plays an increasing role in China's economy since mobility rose and economic restructuring has proceeded during the last three decades. Given the background of most studies focusing on migration in a partic... Migration plays an increasing role in China's economy since mobility rose and economic restructuring has proceeded during the last three decades. Given the background of most studies focusing on migration in a particular period, there is a critical need to analyze the spatial-temporal patterns of migration. Using bicomponent trend mapping technique and interprovincial migration data during the periods 1985-1990, 1990-1995, 1995-2000, 2000- 2005, and 2005-2010 we analyze net-, in-, out-migration intensity, and their changes over time in this study. Strong spatial variations in migration intensity were found in China's interprovincial migration, and substantial increase in migration intensity was also detected in eastern China during 1985-2010. Eight key destinations are mostly located within the three rapidly growing economic zones of eastern China (Pearl River Delta, Yangtze River Delta and Beijing-Tianjin-Hebei Metropolitan Region), and they are classified into three types: mature, emerging, and fluctuant origins, while most key origins are relatively undeveloped central and western provinces, which are exactly in accordance with China's economic development patterns. The results of bicomponent trend mapping indicate that, in a sense, the migration in the south was more active than the north over the last three decades. The result shows the new changing features of spatial-temporal patterns of China's interprovincial migration that Fan and Chen did not find out in their research. A series of social-economic changes including rural transformation, balanced regional development, and labor market changes should be paid more attention to explore China's future interprovincial migration. 展开更多
关键词 China spatial-temporal pattern interprovincial migration bicomponent trend mapping economicand cultural factors
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Spatial-temporal Patterns and Driving Forces of Water Retention Service in China 被引量:14
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作者 XIAO Yang OUYANG Zhiyun 《Chinese Geographical Science》 SCIE CSCD 2019年第1期100-111,共12页
Overwhelming water-deficiency conditions and an unbalanced water supply and demand have been major concerns of both the Chinese government and the general public during recent decades. Studying the spatial-temporal pa... Overwhelming water-deficiency conditions and an unbalanced water supply and demand have been major concerns of both the Chinese government and the general public during recent decades. Studying the spatial-temporal patterns and impact factors that influence water retention in China is important to enhance the management of water resources in China and other similar countries. We employed a revised Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST) model and regression analyses to investigate the water retention service in China. The results showed that the southeastern China generally performed much better than Northwest China in terms of the spatial distribution of water retention. In general, the efficacy of the water retention service in China increased from 2000 to 2014; although some areas still had a downward trend. Water retention service increased significantly(P < 0.05) in aggregate in the Qinghai-Tibet Plateau, and the Da Hinggan Mountains and Xiao Hinggan Mountains. However, the service in southwestern China showed a decreasing trend(P < 0.05), which would have significant negative impact on the downstream population. This study also showed that in China the changes in water retention service were primarily due to climate change(which could explain 83.49% of the total variance), with anthropogenic impact as a secondary influence(likewise the ecological programs and socioeconomic development could explain 9.47% and 1.06%, respectively). Moreover, the identification of water retention importance indicated that important areas conservation and selection based on downstream beneficiaries is vital for optimization protection of ecosystem services, and has practical significance for natural resources and ecosystem management. 展开更多
关键词 WATER RETENTION spatial-temporal pattems driving FACTORS China
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Spatial-temporal patterns of major ion chemistry and its controlling factors in the Manasarovar Basin, Tibet 被引量:11
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作者 YAO Zhijun WANG Rui +2 位作者 LIU Zhaofei WU Shanshan JIANG Liguang 《Journal of Geographical Sciences》 SCIE CSCD 2015年第6期687-700,共14页
The Manasarovar Basin in southern Tibet, which is considered a holy land in Buddhism, has drawn international academic attention because of its unique geographical environment. In this study, based on actual measureme... The Manasarovar Basin in southern Tibet, which is considered a holy land in Buddhism, has drawn international academic attention because of its unique geographical environment. In this study, based on actual measurements of major ion concentrations in 43 water samples collected during the years 2005 and 2012, we analyzed systemically the spatialtemporal patterns of water chemistry and its controlling factors in the lake and inflowing rivers. The results reveal that the water in the Manasarovar Basin is slightly alkaline, with a pH ranging between 7.4-7.9. The amounts of total dissolved solids (TDS) in lake and river waters are approximately 325.4 and 88.7 mg/l, respectively, lower than that in most of the surface waters in the Tibetan Plateau. Because of the long-term effect of evaporative crystallization, in the lake, Na^+ and HCO3^- have the highest concentrations, accounting for 46.8% and 86.8% of the total cation and anion content. However, in the inflowing rivers, the dominant ions are Ca^2+ and HCO3^-, accounting for 59.6% and 75.4% of the total cation and anion content. The water exchange is insufficient for such a large lake, resulting in a remarkable spatial variation of ion composition. There are several large inflowing rivers on the north side of the lake, in which the ion concentrations are significantly higher than that on the other side of the lake, with a TDS of 468.9 and 254.9 mg/l, respectively. Under the influence of complicated surroundings, the spatial variations in water chemistry are even more significant in the rivers, with upstreams exhibiting a higher ionic content. The molar ratio between (Ca^2++Mg^2+) and (Na^++K^+) is much higher than 1.0, revealing that the main source of ions in the waters is carbonate weathering. Although natural processes, such as rock weathering, are the major factors controlling main ion chemistry in the basin, in the future we need to pay more attention to the anthropogenic influence. 展开更多
关键词 Manasarovar surface water chemistry spatial-temporal distribution rock weathering Tibetan Plateau
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The evolution of the spatial-temporal patterns of global energy security since the 1990s 被引量:7
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作者 WANG Qiang XU Linglin +4 位作者 LI Na DU Xue WU Shidai TIAN Lanlan WU Chenlu 《Journal of Geographical Sciences》 SCIE CSCD 2019年第8期1245-1260,共16页
In this study, we developed an energy security evaluation model(ESEM) from three dimensions, energy supply-transport security, safety of energy utilization, and stability of political-socioeconomic environment, based ... In this study, we developed an energy security evaluation model(ESEM) from three dimensions, energy supply-transport security, safety of energy utilization, and stability of political-socioeconomic environment, based on the integrated application of subjective and objective weight allocation technique. Then the spatial-temporal evolution of global energy security pattern and its driving mechanism was analyzed with the method above, and the results are shown as follows:(1) since the 1990 s, the spatial patterns of global energy security have shown a deteriorating trend, with the growth of countries in at-risk type and relatively at-risk type.(2) The spatial distribution of countries with secure energy system shows a strong stability, and these countries are concentrated persistently in Western Europe and North America. The spatial evolution of countries with relatively secure energy system also presents a strong stability, which are mainly distributed in the periphery of the secure ones, namely Central and Southern Europe, South America and Eurasia, while countries with general energy system are mainly distributed in Asia, Africa and Southern Europe, and the spatial-temporal evolution of this type is the main cause for the deterioration of world energy security pattern. Countries with at-risk and relatively at-risk energy system are mainly concentrated in Africa, Asia, the Middle East and Eurasia, rendering spatial extension to the east and south.(3) In the past 20 years, the mechanism for world’s energy security pattern formation gradually transforms from the ‘unitary dimension dominated’ to the ‘binary dimension-dominated’, and the main factors influencing the global energy security pattern become more diverse.(4) In the pattern of world’s energy security, China’s performance on energy security has been the global average since the 1990 s, which shows a decreasing trend in safety of energy utilization dimension. Findings in this study can provide a reference for the government in terms of formulating strategic responses and policy options. 展开更多
关键词 energy SECURITY spatial-temporal EVOLUTION subjective-objective WEIGHT ALLOCATION method the globe
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Characterizing urban expansion of Korla City and its spatial-temporal patterns using remote sensing and GIS methods 被引量:6
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作者 Bumairiyemu MAIMAITI DING Jianli +1 位作者 Zibibula SIMAYI Alimujiang KASIMU 《Journal of Arid Land》 SCIE CSCD 2017年第3期458-470,共13页
Cities provide spatial contexts for populations and economic activities. Determining the spatial-temporal patterns of urban expansion is of particular significance for regional sustainable development. To achieve a be... Cities provide spatial contexts for populations and economic activities. Determining the spatial-temporal patterns of urban expansion is of particular significance for regional sustainable development. To achieve a better understanding of the spatial-temporal patterns of urban expansion of Korla City, we explore the urban expansion characteristics of Korla City over the period 1995-2015 by employing Landsat TM/ETM+ images of 1995, 2000, 2005, 2010, and 2015. Urban land use types were classified using the supervised classification method in ENVI 4.5. Urban expansion indices, such as expansion area, expansion proportion, expansion speed, expansion intensity, compactness, and fractal dimension, were calculated. The spatial-temporal patterns and evolution process of the urban expansion (e.g., urban gravity center and its direction of movement) were then quantitatively analyzed. The results indicated that, over the past 25 years, the area and proportion of urban land increased substantially with an average annual growth rate of 15.18%. Farmland and unused land were lost greatly due to the urban expansion. This result might be attributable to the rapid population growth and the dramatic economic development in this area. The city extended to the southeast, and the urban gravity center shifted to the southeast as well by about 2118 m. The degree of urban compactness tended to decrease and the fractal dimension index tended to increase, indicating that the spatial pattern of Korla City was becoming loose, complex, and unstable. This study could provide a scientific reference for the studies on urban expansion of oasis cities in arid land. 展开更多
关键词 urban expansion spatial-temporal changes urban land remote sensing and GIS Korla City
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Spatial-temporal Patterns and Evolution History of Rural Settlements from the Perspective of Inheritance——A Case Study of Lianzhou City,Guangdong Province 被引量:3
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作者 CAO Xiaoshu REN Huizi +1 位作者 HUANG Xiaoyan LIU Jieyu 《Journal of Landscape Research》 2013年第6期39-42,45,共5页
Formation and evolution of rural settlement patterns in Lianzhou City,Guangdong Province were analyzed from the perspective of space and time,on the basis of its gazetteer and relevant historical data.The results show... Formation and evolution of rural settlement patterns in Lianzhou City,Guangdong Province were analyzed from the perspective of space and time,on the basis of its gazetteer and relevant historical data.The results show that Lianzhou was first founded in the sixth year of Yuanding Period of the Western Han Dynasty,and its development could be roughly classified into 6 stages according to the construction of south–north traffic lines and regional development progress,and it witnessed the fastest development in the Ming and Qing Dynasty.In terms of spatial distribution,rural settlements in the local area show spatial continuity,Lianzhou Town is the core of rural settlement growth in the city,and towns with the most concentrated rural settlements in all stages are located in central-west and northeast parts of the city,and those with lower density of rural settlements are mostly located in minority regions in the north and mountainous areas in the east.On the basis of the above facts,the paper studies the influence of natural geological conditions,immigrant,traffic,economic development and ethnic composition on the establishment and development of rural settlements in Lianzhou City. 展开更多
关键词 RURAL SETTLEMENT SETTLEMENT DENSITY spatial-temporal evolution CONTINUITY Lianzhou
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Spatial-temporal Patterns and Influencing Factors of Green and Low-carbon Technology Innovation:Evidence from Chinese Cities
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作者 GAO Xin GU Weinan 《Chinese Geographical Science》 2026年第4期590-605,共16页
As a crucial motivator for China to advance the‘dual carbon'target,green and low-carbon technology innovation(GLCTI)not only provides a technological path for the realization of carbon reduction,zero carbon,and n... As a crucial motivator for China to advance the‘dual carbon'target,green and low-carbon technology innovation(GLCTI)not only provides a technological path for the realization of carbon reduction,zero carbon,and negative carbon but also plays a role in promoting the low-carbon transformation of the socio-economic development.In this case,it is necessary to explore the spatial-temporal characteristics and influencing factors of GLCTI.Green and low-carbon patent data gathered via a web crawler were utilized to indicate the level of GLCTI from 2002 to 2020.Spatial Analysis,Spatial Autocorrelation,and Spatial Durbin Model were used to investigate the spatial-temporal evolution and influencing factors of GLCTI in China.The results show that:1)whether it was the number of patents granted or the number of city participation,fossil energy carbon reduction technology had been leading GLCTI across the country;2)the cities demonstrating stronger GLCTI performance in China are primarily located in the eastern coastal regions and provincial capitals of the central and western areas,with significant spatial differentiation characteristics;3)Chinese urban GLCTI was booming in low-carbon field,and non-resource-based cities had better conditions for the development of GLCTI;4)significant spatial spillover effects and path-dependent features were observed in Chinese urban GLCTI.Talent reserve,financial investment,foreign direct investment,urban economic scale,tertiary industry-based industrial structure,and urban air quality are the key variables to enhance cities'capacity in GLCTI,while the secondary industry-based industrial structure has an inhibitory and constraining effect.The results could provide a practical reference for the development of GLCTI in China and promote the realization of the‘dual-carbon'target. 展开更多
关键词 green and low-carbon technology innovation(GLCTI) spatial-temporal pattern urban-type influencing factor Spatial Durbin Model(SDM) China
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Seasonal emission patterns of airborne phytoncides in temperate forests from autumn to early spring:a case study of Xishui National Forest Park(Yichun,Northeast China)
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作者 Hongda Cai Yitong Wang +6 位作者 Xianwen Huang Sen Zhang Yankun Liu Jian Zhang Dongmei Zhao Peng Zhao Xiuhua Zhao 《Journal of Forestry Research》 2026年第1期256-271,共16页
Xishui National Forest Park in Heilongjiang Province hosts China's most pristine temperate forests and serves as a key site for ecotourism and forest therapy.However,the emission patterns of phytoncides(key bio ac... Xishui National Forest Park in Heilongjiang Province hosts China's most pristine temperate forests and serves as a key site for ecotourism and forest therapy.However,the emission patterns of phytoncides(key bio active compounds) remain poorly understood,limiting their therapeutic application.This study provides the first comprehensive characterization of spatiotemporal dynamics in airborne phytoncides and their synergistic interactions with environmental factors throughout the autumn-early spring seasonal transition in a temperate forest ecosystem.We analyzed the compositional dynamics of phytoncides and terpenoid content variations using thermal desorption-gas chromatography-mass spectrometry(TD-GC-MS) from September 2024 to March 2025.This period encompassed seasonal transitions from autumn to early spring,including diurnal variations in September and snowfall events in November.The method demonstrated detection limits(LODs) ranging from 1.35 to 5.33 ng m-3 and quantification limits(LOQs) from 4.09 to 16.15 ng m-3.Our results revealed pronounced seasonal fluctuations in phytoncide composition.In September,terpenoids,esters,alcohols,and alkanes displayed a diurnal "decrease-increase" trend,whereas aldehydes and ketones peaked at midday.Notably,esters and alcohols were undetectable in November and January.By January,terpenoids reached their lowest proportion(0.17±0.02%) at noon.Five terpenoids(α-pinene,myrcene,D-limonene,camphene,p-cymene) were detected in September,four(α-pinene,D-limonene,camphene,p-cymene) in November,two(D-limonene,p-cymene) in January,and only p-cymene in March.The total concentration and emission rate of the five terpenoids peaked in September afternoons at 1961.58±106.67 ng m^(-3) and653.86±35.56 ng m^(-3) h^(-1),respectively.Nocturnal emissions(32131.95±2522.21 ng m^(-3)) significantly surpassed daytime levels(14473.04±958.49 ng m^(-3)),with emission rates escalating from 1447.30±95.85 ng m^(-3) h^(-1)(day) to 5355.33±420.37 ng m^(-3) h^(-1)(night),marking a3.7-fold increase.Snowfall dramatically elevated terpenoid concentrations(pre-snowfall:158.58±14.12 ng m^(-3);post-snowfall:1080.57±57.76 ng m^(-3)) and emission rates(pre-snowfall:52.86±4.71 ng m^(-3) h^(-1);post-snowfall:360.19±19.25 ng m^(-3) h^(-1)),reflecting a 6.8-fold surge.This study underscores the profound influence of light intensity,seasonal shifts,and climatic conditions on airborne phytoncide levels,offering a scientific foundation for optimizing forest therapy and ecotourism strategies. 展开更多
关键词 Phytoncides Seasonal variation Diurnal-nocturnal patterns Snowfall impact Emission patterns
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Spatial-Temporal Dynamics of Dongzhaigang Mangrove Forests on Hainan Island,China:Evidence from Landsat Observations(1988–2019)
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作者 Bing Tu Kang Peng +4 位作者 Xianjun Xie Lu Yan Yamin Deng Yiqun Gan Qinghua Li 《Journal of Earth Science》 2026年第1期289-302,共14页
The goal of this study was to determine the spatiotemporal characteristics of mangrove distribution and fragmentation patterns from 1988 through 2019 in Dongzhaigang.Land cover datasets were generated for Dongzhaigang... The goal of this study was to determine the spatiotemporal characteristics of mangrove distribution and fragmentation patterns from 1988 through 2019 in Dongzhaigang.Land cover datasets were generated for Dongzhaigang for multiple years via a decision tree method based on a classification and regression tree(CART)algorithm using Landsat time series images.Spatiotemporal transform and fragmentation patterns of mangrove distribution were separately assessed with a transfer matrix of land cover types and a landscape pattern index.The classification method combined with multi-band images showed good accuracy,with overall accuracy higher than 90%.Mangrove areas in 1988,1999,2009,and 2019 were 2050,1875,1818,and 1750 ha,respectively,with decreases mainly due to conversion to aquaculture ponds and farmland.A mangrove growth index(MGI)was proposed,reflecting the water-mangrove relationship,showing positive mangrove growth from 1988–2009 and negative growth from 2009–2019.Study results indicated anthropogenic factors play a leading role in the extent and scale of mangrove effects over the past 30 years.According to the analysis results,corresponding management and protection measures are proposed to provide reference for the sustainable development of Dongzhaigang Mangrove Wetland ecosystem. 展开更多
关键词 mangrove forests spatial-temporal data Hainan Island decision trees Landsat image
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Incorporating multiple scenarios and landscape ecological risk to optimize ecological security patterns: A Wei River Basin case study
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作者 Xueting Wu Jinghu Pan 《Chinese Journal of Population,Resources and Environment》 2026年第1期94-109,共16页
Under the influence of human activities,landscape fragmentation in the Wei River Basin(WRB)has become increasingly severe.Upstream development has intensified soil erosion,and industrial and agricultural pollution in ... Under the influence of human activities,landscape fragmentation in the Wei River Basin(WRB)has become increasingly severe.Upstream development has intensified soil erosion,and industrial and agricultural pollution in the middle reaches has degraded water quality.Rapid urbanization has further caused habitat fragmentation and biodiversity loss.Collectively,these challenges threaten human well-being and hinder sustainable development,making the construction and optimization of an ecological security pattern(ESP)urgently necessary.However,existing studies often fail to systematically integrate future landscape ecological risk(LER)assessment with ESP optimization.This study evaluated regional LER using the“ecological patches-ecological resistance surface(ERS)-ecological corridor”framework,combined with land-use predictions under three development scenarios,and optimized the ESP by adjusting the ERS and extracting ecological corridors.The results indicate that the LER in the WRB follows an“inverted N”distribution,with low-risk areas concentrated in forested mountain regions and high-risk areas mainly in cultivated land subject to intensive human activity.Across future scenarios,ESPs showed fewer ecological breakpoints and improved landscape connectivity than the 2020 baseline.Scenario-based differences emerged in the spatial configuration of ERS adjustments,with the ecological protection scenario yielding the lowest LER and most favorable ESP.This study demonstrates the deep integration of multi-scenario simulation with LER assessment,providing a new framework for ESP optimization.The findings have guiding significance for ecological protection and coordinated development in the WRB and offer a novel paradigm for sustainable development in ecologically fragile basins worldwide. 展开更多
关键词 Ecological security pattern Multiple scenarios Landscape ecological risk Ecological security pattern optimization
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A novel deviation measurement for scheduled intelligent transportation system via comparative spatial-temporal path networks
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作者 Daozhong Feng Jiajian Lai +1 位作者 Wenxuan Wei Bin Hao 《Digital Communications and Networks》 2026年第1期101-118,共18页
Transit managers can use Intelligent Transportation System technologies to access large amounts of data to monitor network status.However,the presentation of the data lacks structural information.Existing single-netwo... Transit managers can use Intelligent Transportation System technologies to access large amounts of data to monitor network status.However,the presentation of the data lacks structural information.Existing single-network description technologies are ineffective in representing the temporal and spatial characteristics simultaneously.Therefore,there is a need for complementary methods to address these deficiencies.To address these limitations,this paper proposes an approach that combines Network Snapshots and Temporal Paths for the scheduled system.A dual information network is constructed to assess the degree of operational deviation considering the planning tasks.To validate the effectiveness,discussions are conducted through a modified cosine similarity calculation on theoretical analysis,delay level description,and the ability to identify abnormal dates.Compared to some state-of-the-art methods,the proposed method achieves an average Spearman delay correlation of 0.847 and a relative distance of 3.477.Furthermore,case analyses are invested in regions of China's Mainland,Europe,and the United States,investigating both the overall and sub-regional network fluctuations.To represent the impact of network fluctuations in sub-regions,a response loss value was developed.The times that are prone to fluctuations are also discussed through the classification of time series data.The research can offer a novel approach to system monitoring,providing a research direction that utilizes individual data combined to represent macroscopic states.Our code will be released at https://github.com/daozhong/STPN.git. 展开更多
关键词 Intelligent transportation system Air traffic network Deviation measurement spatial-temporal path networks Operational monitoring
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Thoughts on the scientific research of the connotation of traditional Chinese medicine patterns
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作者 Kang Xie Yulin Ouyang +1 位作者 Yong Wang Chun Li 《Journal of Traditional Chinese Medical Sciences》 2026年第1期3-11,共9页
Traditional Chinese medicine(TCM)is a holistic medical system that classifies and treats diseases based on the concept of patterns.These patterns describe the pathophysiological process of a disease at a specific stag... Traditional Chinese medicine(TCM)is a holistic medical system that classifies and treats diseases based on the concept of patterns.These patterns describe the pathophysiological process of a disease at a specific stage,reflecting both external signs and internal features.TCM patterns are central to pattern differentiation,treatment,clinical practice,and theoretical development in TCM.However,scientific explanation of TCM patterns remains limited because of subjective diagnostic criteria,the absence of a standardized experimental medical system,and unclear biological mechanisms,which restrict the modernization and globalization of TCM.Addressing challenges such as strong subjectivity in diagnosis,lack of standardized experimental systems,and unclear biological mechanisms is necessary to clarify the scientific meaning of TCM patterns and to provide technical approaches for the modernization and globalization of TCM.A strategy focused on“pathogenic factors,genetic predisposition,and disease progression stages”was adopted.This approach included the following:(Ⅰ)constructing disease-pattern integrated biological models with animal models,organoids,and multi-organ chips;(Ⅱ)applying multi-omics technologies,such as spatial omics,single-cell omics,and dynamic metabolic flux omics;(Ⅲ)using artificial intelligence(AI)and big data for data integration and prediction of pattern evolution;and(Ⅳ)validating formula–pattern associations through the“pattern differentiation through formula efficacy”approach.These strategies directly address the main obstacles in TCM pattern research by providing objective,quantifiable,and reproducible methodologies.Constructing disease-pattern integrated models enabled cross-scale research platforms.Applying multi-omics technologies allowed analysis of complex biological bases.AI and big data approaches addressed challenges related to heterogeneous data.The“formula-based pattern differentiation”approach supported precise interventions and the development of new drugs.This interdisciplinary framework advances TCM pattern research by moving from empirical description to objective quantification.By integrating innovative approaches,the study establishes a foundation for systematic,evidence-based TCM diagnosis and treatment,supporting accuracy and promoting international recognition and modernization of TCM.The study shows that combining multi-omics technologies,AI-driven data analysis,and disease-pattern models enables objective quantification of TCM patterns and clarifies their biological mechanisms. 展开更多
关键词 Traditional Chinese medicine patterns Disease-pattern integrated model Multi-omics technology Artificial intelligence pattern differentiation through formula efficacy
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Species Diversity and Elevational Patterns of Reptiles in the Leigongshan National Nature Reserve, Guizhou Province, China
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作者 Xue GOU Caichun PENG +7 位作者 Tuo SHEN Chaobo FENG Lang MU Jing LIU Haijun SU Xiujun TANG Shize LI Xingui LI 《Asian Herpetological Research》 2026年第1期31-33,共3页
Dear Editor,Understanding patterns of species diversity is a primary research focus in macroecology,with its distribution patterns having been described and theoretically validated on a global scale(Peters et al.,2016... Dear Editor,Understanding patterns of species diversity is a primary research focus in macroecology,with its distribution patterns having been described and theoretically validated on a global scale(Peters et al.,2016;Sonne et al.,2025).Numerous studies have found that species richness of different taxa tends to decrease with increasing elevation and is modulated by latitudinal gradients(Peters et al.,2016;Dolson et al.,2024).This principle provides a crucial scientific basis for regional conservation planning.However,it still exhibits significant variations across different mountain ranges and taxa. 展开更多
关键词 patterns species diversity Leigongshan National Nature Reserve species richness Guizhou Province reptiles species diversity elevational patterns regional conservation plannin
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Variation in vegetation characteristics and landscape patterns of urban forests:implications for ecosystem management under rapid urbanization
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作者 Jialin Zhong Jiamei Tu +5 位作者 Xin Li Yao Fu Wei Liu Foyi Zhang Shuyang Hu Qiong Wang 《Journal of Forestry Research》 2026年第2期224-238,共15页
Urban forests are essential components of green infrastructure,however,rapid urbanization-induced changes in landscape patterns may affect their ecosystem services through complex ecological processes.A total of 184 s... Urban forests are essential components of green infrastructure,however,rapid urbanization-induced changes in landscape patterns may affect their ecosystem services through complex ecological processes.A total of 184 sample plots in the built-up areas of Nanchang,China,were used as research sites.Urbanization intensities were categorized by the rate of impervious surface area,and forest types were classified into landscape and relaxation forest,attached forest(AF),road forest(RF),and ecological public welfare forest.This study aimed to explore the spatial variations in vegetation characteristics and landscape pattern indices of different forest types under rapid urbanization.The results indicated that the largest patch index(LPI),aggregation index(AI),and percentage of landscape(PLAND)in RF and AF were lower than those in the other forest types(p<0.05).With increasing urbanization intensity,the mean perimeter-area ratio increased by 130.84%,whereas the PLAND,LPI,and AI decreased by 22−86%(p<0.05).Redundancy analysis and variation partitioning suggested that the interpretation rate of landscape pattern indices for variations in vegetation characteristics increased from low to heavy urbanization areas.Especially,the landscape shape index,patch connection index,PLAND,and mean patch size were significantly correlated with vegetation characteristics(e.g.,tree richness,herb coverage,and tree height).In the future,appropriate landscape layout superiority cases should be considered in different urbanization areas and forest types;for instance,increasing the patch connection index will beneficially improve the diversity of trees and herbs in heavy urbanization areas and the RF.This study serves as a reference for maximizing the ecosystem services of urban forests. 展开更多
关键词 Forest type VEGETATION URBANIZATION Landscape pattern
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Thermal stability design for flexural wave bandgap of metamaterial plates with perforated and pre-curved patterns
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作者 Qian GENG Xing ZHOU +3 位作者 Mengyang WANG Xiongwei YANG Zhushan SHAO Yueming LI 《Applied Mathematics and Mechanics(English Edition)》 2026年第3期443-472,I0001-I0004,共34页
A design idea for single-component metamaterial plates is proposed to achieve the thermal stability of flexural wave bandgap by the perforated and pre-curved patterns.The band structure analysis suggests that perforat... A design idea for single-component metamaterial plates is proposed to achieve the thermal stability of flexural wave bandgap by the perforated and pre-curved patterns.The band structure analysis suggests that perforation can release part of the in-plane thermal expansion to weaken the softening effect of thermal stress.Introducing precurved components to the perforated structure will stop the decrement of the bandgap frequency in thermal environment,and even make the frequency higher with appropriate structural parameters.The bending stiffness of the heated plate is enhanced by the thermal deflection induced stiffening effect of the pre-curved components.The segmented pre-curved component presents a strong ability to resist the thermal influence on the flexural wave bandgap.A simplified model is established for the local structure of the precurved component.The theoretical calculations explain the thermally induced frequency increment of the bandgap and the discrepancy in the thermal response between the two pre-curved models.The transmittance of flexural wave validates the effectiveness of the proposed design. 展开更多
关键词 metamaterial plate flexural vibration bandgap PERFORATION pre-curved pattern thermal stability
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Patterns of utilization of antipsychotic drugs and direct medical costs among patients with schizophrenia in a tertiary care hospital
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作者 Aqeel Haider Lekha Saha Debashish Basu 《World Journal of Psychiatry》 2026年第1期125-135,共11页
BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Resear... BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Research in developing nations relating to the cost of treatment is scarce when compared with developed countries.Thus,the drug utilization research studies from developing nations are most needed,and their number has been growing.AIM To evaluate patterns of utilization of antipsychotic drugs and direct medical cost analysis in patients newly diagnosed with schizophrenia.METHODS The present study was observational in type and based on a retrospective cohort to evaluate patterns of utilization of antipsychotic drugs using World Health Organization(WHO)core prescribing indicators and anatomical therapeutic chemical/defined daily dose indicators.We also calculated direct medical costs for a period of 6 months.RESULTS This study has found that atypical antipsychotics are the mainstay of treatment for schizophrenia in every age group and subcategories of schizophrenia.The evaluation based on WHO prescribing indicators showed a low average number of drugs per prescription and low prescribing frequency of antipsychotics from the National List of Essential Medicines 2015 and the WHO Essential Medicines List 2019.The total mean drug cost of our study was 1396 Indian rupees.The total mean cost due to the investigation in our study was 1017.34 Indian rupees.Therefore,the total mean direct medical cost incurred on patients in our study was 4337.28 Indian rupees.CONCLUSION The information from the present study can be used for reviewing and updating treatment policy at the institutional level. 展开更多
关键词 patterns of utilization Antipsychotic drugs Direct medical cost SCHIZOPHRENIA DRUGS
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Effects of wetland connectivity on plant communities and vegetation patterns in the Qaidam Basin
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作者 YUE Yifan MA Dengke +3 位作者 MA Yuanyuan KANG Wenrong ZHOU Guoying ZHAO Wenzhi 《Journal of Arid Land》 2026年第4期696-714,共19页
The Qaidam Basin,a typical alpine arid inland basin on the northern Qinghai-Xizang Plateau,China,hosts wetland ecosystems that are strongly constrained by topography and extreme climate.These ecosystems exhibit pronou... The Qaidam Basin,a typical alpine arid inland basin on the northern Qinghai-Xizang Plateau,China,hosts wetland ecosystems that are strongly constrained by topography and extreme climate.These ecosystems exhibit pronounced spatiotemporal heterogeneity and fragmented distribution patterns,rendering them highly sensitive to environmental change.This study integrated Sentinel-2 remote sensing imagery with the SedInConnect model to delineate wetland patch distributions and calculate the Index of Connectivity(IC)values across the basin.Based on IC values,we stratified field sampling sites into high-,moderate-,and lowconnectivity gradient groups to analyze the relationships among plant community characteristics,vegetation spatial patterns,and wetland connectivity in the Qaidam Basin.Partial Least Squares Path Modeling(PLSPM)was further employed to quantify the driving mechanisms underlying wetland vegetation characteristics.The results revealed that wetland connectivity across the basin was generally low,with IC values up to 1.32 and displaying a west-to-east decreasing gradient.The west and northwest were characterized by relatively continuous high-connectivity wetland networks,while fragmented and low-connectivity wetlands predominated in the east and southeast.Connectivity regulated wetland vegetation patterns primarily by affecting patch size,fragmentation,and internal adjacency.High-connectivity areas had higher class area(CA),largest patch index(LPI),and area-weighted mean patch size(AREA_AM)than low-connectivity areas.Connectivity had the strongest effect on vegetation coverage,which declined sharply from 87.577%in highconnectivity areas to 12.152%in low-connectivity areas.Meanwhile,species diversity showed a moderately negative response to connectivity changes,whereas species evenness remained relatively unaffected.PLS-PM explained 78.300%and 67.500%of the variance in vegetation community and vegetation pattern,respectively.Climate played a dominant role in shaping vegetation characteristics,with significant negative effects on both vegetation community and pattern.Topography influenced vegetation indirectly through climate,and connectivity was influenced by both drivers and exerted positive effects on vegetation community and pattern.This study reveals the multi-pathway driving mechanisms underlying vegetation pattern formation in alpine wetlands,providing a theoretical foundation and decision-support framework for the scientific conservation and adaptive management of wetlands in the Qaidam Basin. 展开更多
关键词 connectivity gradient wetland vegetation vegetation pattern community characteristics driving mechanisms
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Unravelling tree diversity patterns and responses to environmental gradients in a tropical forest landscape of the Western Ghats
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作者 Naveen Babu Kanda Ashaq Ahmad Dar +2 位作者 Kurian Ayushi Ayyappan Narayanan Narayanaswamy Parthasarathy 《Plant Diversity》 2026年第1期92-106,共15页
Understanding spatial patterns of plant species diversity and the factors(e.g.,climate and human)that drive these patterns is essential for biodiversity conservation.We used data from 1700.1-ha forest plots in the She... Understanding spatial patterns of plant species diversity and the factors(e.g.,climate and human)that drive these patterns is essential for biodiversity conservation.We used data from 1700.1-ha forest plots in the Shettihalli tropical forest landscape of the Western Ghats biodiversity hotspot,India,to analyse tree community composition and the drivers of α-diversity(Shannon)andβ-diversity(LCBD).Compositional patterns were visualized using Non-Metric Multidimensional Scaling(NMDS),and hybrid feature selection with structural equation modeling(SEM)was employed to evaluate the direct and indirect effects of environmental variables on diversity.NMDS identified four distinct forest types in the Shettihalli landscape:semi-evergreen,dry deciduous,moist deciduous,and plantation forests,each with distinct plant composition.Shannon diversity and ecological uniqueness was significantly higher in semi-evergreen forest than in deciduous forest plots.The SEMs explained about 79%and 39–45%of the variation in α-diversity andβ-diversity.Our analysis indicated that current diversity patterns result from multiple processes,with structure,disturbance,and edaphic parameters exerting the strongest direct and indirect effects onα-diversity.β-diversity,in contrast,was largely influenced by climate,topography,stand structure,and edaphic factors.Overall,our findings indicate that various factors(e.g.,climate,topography,and human disturbance)interact to shape tree diversity patterns in tropical forests.These findings will help develop unique conservation and management strategies for distinct forest types in tropical forest ecosystems. 展开更多
关键词 Alpha diversity Beta diversity Machine learning Structural equation modeling Vegetation patterns Western Ghats
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Typical blood parameters and gut microbiota alterations associated with the mutual conversion of cold and hot patterns induced by Chinese herbal medicines
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作者 Yanan Yang Yuxiao Li +2 位作者 Kebin Wang Shengxian Wu Chongming Wu 《Journal of Traditional Chinese Medical Sciences》 2026年第1期34-47,共14页
Objective:To elucidate the quantification and standardization of cold and hot patterns,the fundamental concepts in traditional Chinese medicine(TCM).Methods:This randomized cross-controlled trial recruited 30 healthy ... Objective:To elucidate the quantification and standardization of cold and hot patterns,the fundamental concepts in traditional Chinese medicine(TCM).Methods:This randomized cross-controlled trial recruited 30 healthy volunteers.Participants in Group 1 underwent 14 days of Coptis chinensis Franch.(C.chinensis,Huang Lian)treatment to shift their body toward the cold pattern,followed by 7 days of washout and 14 days of Cinnamomum cassia Presl(C.cassia,Rou Gui)treatment to shift their body toward the hot pattern.Participants in Group 2 underwent the opposite treatment.Blood and stool samples were collected for routine blood testing and full-length 16S rRNA metagenomic sequencing.Results:Red blood cells(RBC),hemoglobin(HGB),hematocrit(HCT),and blood platelet count(BPC)were increased by C.chinensis,whereas the mean corpuscular HGB concentration(MCHC)was increased by C.cassia.RBC,HGB,HCT,and BPC were positively associated with the cold pattern but negatively correlated with the hot pattern,whereas MCHC showed opposite relationships.C.chinensis-increased Blautia stercoris was positively correlated with RBC,HGB,and HCT under C.chinensis treatment,whereas C.cassia-enhanced Parabacteroides distasonis_A was positively associated with MCHC under C.cassia treatment.Interestingly,five indicators(RBC,HGB,HCT,Blautia stercoris,and Prevotella copri)had an area under the curve of 0.795 for predicting the cold pattern.Although three indicators(MCHC,Akkermansia sp004167605,and Parabacteroides distasonis_A)showed poor predictive ability for the hot pattern,when the individual’s gut microbiota experienced disturbance by cold Chinese materia medica stimulation,the predictive ability increased to 0.703.Conclusion:This study suggests that blood parameters and gut microbes may be potential indicators of hot and cold TCM patterns,which could benefit the objectivity and scientific rigor of TCM. 展开更多
关键词 Traditional Chinese medicine pattern differentiation Gut microbiota Coptis chinensis Franch Cinnamomum cassia Presl
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The influence of three-dimensional gray landscape patterns on urban surface temperature:A case study of Beijing,China
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作者 Linlin Zhao Kun Jia +5 位作者 Yanxu Liu Guofeng Tao Jie Li Bo Yuan Yuran Cui Shijiao Qiao 《Ecological Frontiers》 2026年第1期167-177,共11页
The rapid urbanization has significantly accelerated the expansion of cities and led to a notable increase in urban land surface temperature(LST).Currently,most studies mainly examine the effects of two-dimensional(2D... The rapid urbanization has significantly accelerated the expansion of cities and led to a notable increase in urban land surface temperature(LST).Currently,most studies mainly examine the effects of two-dimensional(2D)landscape patterns on LST variations,and research investigating the relationship between three-dimensional(3D)urban landscape patterns and LST remains relatively scarce.Therefore,this study utilizes partial correlation analysis and piecewise linear regression to systematically investigate the impacts of gray landscape indicators on LST variations under both 2D and 3D urban patterns,aiming to elucidate the complex relationship between 3D urban landscape patterns and LST dynamics.The results demonstrate that specific 3D building characteristics,particularly the area of low-rise buildings,building aggregation degree,shape complexity,and patch density of mid-rise buildings,serve as effective indicators of urban thermal environment risk.The analysis reveals that increased area-related indicators for low-rise buildings significantly exacerbate the LST rise,whereas modifications to the landscape shape of middle and high-rise buildings contribute to thermal mitigation.Additionally,when gray landscape aggregation exceeds 80%,the spatial concentration of mid-rise buildings exhibits a pronounced positive effect on moderating urban LST.These findings elucidate the mechanisms through which 3D landscape patterns influence urban thermal risks in Beijing,advancing the understanding of urban landscape-ecological processes interactions and providing crucial scientific support for landscape optimization and urban thermal environment risk mitigation strategies. 展开更多
关键词 Land surface temperature 3D landscape patterns Thermal environment risk Landscape optimization
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