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FIXED-TIME PASSIVITY AND SYNCHRONIZATION OF SPATIOTEMPORAL DIRECTED NETWORKS WITH MULTIPLE WEIGHTS
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作者 Yujie MA Cheng HU Leimin WANG 《Acta Mathematica Scientia》 2026年第1期361-382,共22页
This paper is dedicated to fixed-time passivity and synchronization for multi-weighted spatiotemporal directed networks.First,to achieve fixed-time passivity,a type of decentralized power-law controller is developed,i... This paper is dedicated to fixed-time passivity and synchronization for multi-weighted spatiotemporal directed networks.First,to achieve fixed-time passivity,a type of decentralized power-law controller is developed,in which only one parameter needs to be adjusted in the power-law terms;this greatly decreases the inconvenience of parameter adjustment.Second,several fixed-time passivity criteria with LMI forms are derived by using a Gauss divergence theorem to deal with the spatial diffusion of nodes and by applying the Hölder’s inequality to dispose rigorously the power-law term greater than one in the designed control scheme;this improves the previous theoretical analysis.Additionally,the fixed-time synchronization of spatiotemporal directed networks with multi-weights is addressed as a direct result of fixed-time strict passivity.Finally,a numerical example is presented in order to show the validity of the theoretical analysis. 展开更多
关键词 fixed-time passivity fixed-time synchronization spatiotemporal networks multiple weights directed topology
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Spatiotemporal characteristics of atmospheric CO_(2) under the influence of different industrial emission sources using lidar remote sensing in Nanping,China
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作者 Saifen Yu DaiHao Yu +3 位作者 Qiuwei xia Yixiang Chen Zhen Zhang Haiyun Xia 《Journal of Environmental Sciences》 2026年第1期490-501,共12页
Atmospheric CO_(2) concentrations are predominantly regulated by multiple emission sources,with industrial emis-sions representing a critical anthropogenic driver that significantly influences temporal and spatial het... Atmospheric CO_(2) concentrations are predominantly regulated by multiple emission sources,with industrial emis-sions representing a critical anthropogenic driver that significantly influences temporal and spatial heterogeneity in regional CO_(2) patterns.This study investigated the spatiotemporal distribution of atmospheric CO_(2) in Pucheng and Nanping industrial parks,Nanping City,by conducting field experiments using two coherent differential absorption lidars from 1 August to 31 October 2024.Results showed that the spatial distributions of CO_(2) emis-sions within a 3 km radius were mapped,and the local diffusion processes were clarified.CO_(2) patterns varied differently in two industrial parks over the three-month period:Average CO_(2) concentrations in non-emission areas were 422.4 ppm in Pucheng and 408.7 ppm in Nanping,with the former experiencing higher and more variable carbon emissions;Correlation analysis indicated that synthetic leather factories in Pucheng contributed more to SO_(2) and NO_(x) levels compared to the chemical plant in Nanping;In Pucheng,CO_(2) concentrations were transported from the north at ground-level wind speeds exceeding 4 m/s,while in Nanping,the concentrations dispersed gradually with increasing wind speeds;Forward trajectory simulations revealed that the peak-emission from Pucheng primarily affected southern Fujian,northeastern Jiangxi,and southern Anhui,while the peak-emission from Nanping influenced central and western Fujian and northeastern Jiangxi.Besides,emissions in both industrial parks were higher on weekdays and lower on weekends,reflecting changes in industrial activi-ties.The study underscores the potential of lidar technology for providing detailed insights into CO_(2) distribution and the interactions between emissions,wind patterns,and carbon transport. 展开更多
关键词 LIDAR CO_(2) Wind field spatiotemporal variations Carbon emission
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Marine Cirrus Properties from Satellite Remote Sensing over the South China Sea:Spatiotemporal Variations and a Case Study
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作者 Haorui WENG Yong HAN +2 位作者 Li DONG Qicheng ZHOU Yurong ZHANG 《Advances in Atmospheric Sciences》 2026年第1期191-212,共22页
Cirrus clouds play a crucial role in the energy balance of the Earth-atmosphere system.We investigated the spatiotemporal variations of cirrus over the South China Sea(SCS)using satellite data(MOD08,MYD08,CALIPSO)and ... Cirrus clouds play a crucial role in the energy balance of the Earth-atmosphere system.We investigated the spatiotemporal variations of cirrus over the South China Sea(SCS)using satellite data(MOD08,MYD08,CALIPSO)and reanalysis data(MERRA-2)from March 2007 to February 2015(eight years).The horizontal distribution reveals lower cirrus fraction values in the northern SCS and higher values in the southern region,with minima observed in March and April and maxima sequentially occurring in August(northern SCS,NSCS),September(middle SCS,MSCS),and December(southern SCS,SSCS).Vertically,the cirrus fraction peaks in summer and reaches its lowest levels in spring.Opaque cirrus dominates during summer in the NSCS and MSCS,comprising 53.6%and 55.9%,respectively,while the SSCS exhibits a higher frequency of opaque cirrus relative to other cloud types.Subvisible cirrus clouds have the lowest frequency year-round,whereas thin cirrus is most prominent in winter in the NSCS(46.3%)and in spring in the MSCS(45.3%).A case study from September 2021 further explores the influence of ice crystal habits on brightness temperature(BT)over the SCS.Simulations utilizing five ice crystal shapes from the ARTS DDA(Atmospheric Radiative Transfer Simulator Discrete Dipole Approximation)database and the RTTOV 12.4 radiative transfer model reveal that the 8-column-aggregate shape best represents BT in the NSCS and SSCS,while the large-block-aggregate shape performs better in the SSCS. 展开更多
关键词 CIRRUS spatiotemporal variations satellite observation radiative transfer South China Sea
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Prediction of sea surface pCO_(2)in the South China Sea using Spatiotemporal Convolutional LSTM model
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作者 Shuang LI Yu GAO +4 位作者 Jiannan GAO Yaqi ZHAO Peng HAO Jinbao SONG Chengcheng YU 《Journal of Oceanology and Limnology》 2026年第1期19-35,共17页
The prediction of sea surface partial pressure of carbon dioxide(pCO_(2))in the South China Sea is crucial for understanding the region’s contribution to the global carbon budget and its interactions with climate cha... The prediction of sea surface partial pressure of carbon dioxide(pCO_(2))in the South China Sea is crucial for understanding the region’s contribution to the global carbon budget and its interactions with climate change.We applied the Spatiotemporal Convolutional Long Short-Term Memory(STConvLSTM)model,integrating key environmental factors including sea surface temperature(SST),sea surface salinity(SSS),and chlorophyll a(Chl a),to predict and analyze sea surface pCO_(2)in the South China Sea.The model demonstrated high accuracy in short-term predictions(1 month),with a mean absolute error(MAE)of 0.394,a root mean square error(RMSE)of 0.659,and a coefficient of determination(R^(2))of 0.998.For long-term predictions(12 months),the model maintained its predictive capability,with an MAE of 0.667,RMSE of 1.255,and R^(2)of 0.994.Feature importance analysis revealed that sea surface pCO_(2)and SST were the main drivers of the model’s predictions,whereas Chl a and SSS had relatively minor impacts.The model’s generalization ability was further validated in the northwest Pacific Ocean and tropical Pacific Ocean,where it successfully captured the spatiotemporal variation in pCO_(2)with small prediction errors.The ST-ConvLSTM model provides an efficient and accurate tool for forecasting and analyzing sea surface pCO_(2)in the South China Sea,offering new insights into global carbon cycling and climate change.This study demonstrates the potential of deep learning in marine science and provides a significant technical support for global changes and marine ecosystem research. 展开更多
关键词 sea surface carbon dioxide South China Sea spatiotemporal Convolutional Long Short-Term Memory(ST-ConvLSTM) deep learning
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Demonstration of full-scale spatiotemporal diagnostics of solid-density plasmas driven by an ultra-short relativistic laser pulse using an X-ray free-electron laser
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作者 Lingen Huang Michal Smíd +42 位作者 Long Yang Oliver Humphries Johannes Hagemann Thea Engler Xiayun Pan Yangzhe Cui Thomas Kluge Ritz Aguilar Carsten Baehtz Erik Brambrink Engin Eren Katerina Falk Alejandro Laso Garcia Sebastian Gode Christian Gutt Mohamed Hassan Philipp Heuser Hauke Hoppner Michaela Kozlova Wei Lu Josefine Metzkes-Ng Masruri Masruri Mikhail Mishchenko Motoaki Nakatsutsumi Masato Ota Ozgül Oztürk Alexander Pelka Irene Prencipe Thomas R.Preston Lisa Randolph Martin Rehwald Hans-Peter Schlenvoigt Ulrich Schramm Jan-Patrick Schwinkendorf Sebastian Starke Radka Stefaníková Erik Thiessenhusen Monika Toncian Toma Toncian Jan Vorberger Ulf Zastrau Karl Zeil Thomas E.Cowan 《Matter and Radiation at Extremes》 2026年第1期6-19,共14页
Understanding the complex plasma dynamics in ultra-intense relativistic laser-solid interactions is of fundamental importance for applications of laser-plasma-based particle accelerators,the creation of high-energy-de... Understanding the complex plasma dynamics in ultra-intense relativistic laser-solid interactions is of fundamental importance for applications of laser-plasma-based particle accelerators,the creation of high-energy-density matter,understanding planetary science,and laser-driven fusion energy.However,experimental efforts in this regime have been limited by the lack of accessibility of over-critical densities and the poor spatiotemporal resolution of conventional diagnostics.Over the last decade,the advent of femtosecond brilliant hard X-ray free-electron lasers(XFELs)has opened new horizons to overcome these limitations.Here,for the first time,we present full-scale spatiotemporal measurements of solid-density plasma dynamics,including preplasma generation with tens of nanometer scale length driven by the leading edge of a relativistic laser pulse,ultrafast heating and ionization at the main pulse arrival,the laser-driven blast wave,and transient surface return current-induced compression dynamics up to hundreds of picoseconds after interaction.These observations are enabled by utilizing a novel combination of advanced X-ray diagnostics including small-angle X-ray scattering,resonant X-ray emission spectroscopy,and propagation-based X-ray phase-contrast imaging simultaneously at the European XFEL-HED beamline station. 展开更多
关键词 preplasma generation spatiotemporal diagnostics understanding complex plasma dynamics x ray free electron laser planetary scienceand conventional diagnosticsover solid density plasmas ultra short relativistic laser pulse
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Magnesium and gallium-coloaded microspheres accelerate bone repair via osteogenesis and antibiosis 被引量:2
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作者 Jin Bai Si Shen +7 位作者 Yan Liu Shendan Xu Tianqi Li Zirou Wang Weili Liu Lingling Pu Gang Chen Xinxing Wang 《Bio-Design and Manufacturing》 2025年第1期150-165,I0056-I0059,共20页
Bone defects have serious economic and clinical impacts;however,despite improvements in bone defect management,the range of clinical outcomes remains limited.A variety of biomaterials have been used to treat complex b... Bone defects have serious economic and clinical impacts;however,despite improvements in bone defect management,the range of clinical outcomes remains limited.A variety of biomaterials have been used to treat complex bone defects.However,final bone repair outcomes may be adversely affected by poor osteogenic capacity and risk of infection.Consequently,therapeutic methods are required that reduce bacterial contamination and increase the use of osteogenic biomaterials.Herein,we report the preparation of poly(lactic acid-coglycolic acid)(PLGA)microspheres coloaded with magnesium(Mg^(2+))and gallium(Ga^(3+))ions(Mg-Ga@PLGA),which can fill irregular bone defects and show good biosafety.During in vitro testing,Mg-Ga@PLGA not only showed a synergistic effect on promoting osteogenic differentiation but also inhibited osteoclastic differentiation.Moreover,we found that Mg-Ga@PLGA demonstrated an antibacterial effect.During in vivo testing,Mg Ga@PLGA exhibited strong in situ osteogenic ability.In conclusion,Mg-Ga@PLGA has good potential for treating bone defects at risk of infection. 展开更多
关键词 MICROSPHERE osteogenesis ANTIBACTERIA MAGNESIUM GALLIUM
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Spatiotemporal characteristics and influencing factors of vegetation water use efficiency on the Tibetan Plateau in 2001-2020 被引量:2
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作者 HE Chenyang WANG Yanjiao +1 位作者 YAN Feng LU Qi 《Journal of Geographical Sciences》 2025年第1期39-64,共26页
Water use efficiency(WUE),as a pivotal indicator of the coupling degree within the carbon–water cycle of ecosystems,holds considerable importance in assessment of the carbon–water balance within terrestrial ecosyste... Water use efficiency(WUE),as a pivotal indicator of the coupling degree within the carbon–water cycle of ecosystems,holds considerable importance in assessment of the carbon–water balance within terrestrial ecosystems.However,in the context of global warming,WUE evolution and its primary drivers on the Tibetan Plateau remain unclear.This study employed the ensemble empirical mode decomposition method and the random forest algorithm to decipher the nonlinear trends and drivers of WUE on the Tibetan Plateau in 2001–2020.Results indicated an annual mean WUE of 0.8088 gC/mm·m^(2)across the plateau,with a spatial gradient reflecting decrease from the southeast toward the northwest.Areas manifesting monotonous trends of increase or decrease in WUE accounted for 23.64%and 9.69%of the total,respectively.Remarkably,66.67%of the region exhibited trend reversals,i.e.,39.94%of the area of the Tibetan Plateau showed transition from a trend of increase to a trend of decrease,and 26.73%of the area demonstrated a shift from a trend of decrease to a trend of increase.Environmental factors accounted for 70.79%of the variability in WUE.The leaf area index and temperature served as the major driving forces of WUE variation. 展开更多
关键词 water use efficiency spatiotemporal characteristic influencing factor Tibetan Plateau
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Long-term spatiotemporal variations of ammonia in the Yangtze River Delta region of China and its driving factors 被引量:1
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作者 Jingkai Xue Chengzhi Xing +6 位作者 Qihua Li Shanshan Wang Qihou Hu Yizhi Zhu Ting Liu Chengxin Zhang Cheng Liu 《Journal of Environmental Sciences》 2025年第4期202-217,共16页
This study focuses on the spatiotemporal distribution,urban-rural variations,and driving factors of ammonia Vertical Column Densities(VCDs)in China’s Yangtze River Delta region(YRD)from 2008 to 2020.Utilizing data fr... This study focuses on the spatiotemporal distribution,urban-rural variations,and driving factors of ammonia Vertical Column Densities(VCDs)in China’s Yangtze River Delta region(YRD)from 2008 to 2020.Utilizing data from the Infrared Atmospheric Sounding Interfer-ometer(IASI),Generalized Additive Models(GAM),and the GEOS-Chem chemical transport model,we observed a significant increase of NH_(3)VCDs in the YRD between 2014 and 2020.The spatial distribution analysis revealed higher NH_(3)concentrations in the northern part of the YRD region,primarily due to lower precipitation,alkaline soil,and intensive agricul-tural activities.NH_(3)VCDs in the YRD region increased significantly(65.18%)from 2008 to 2020.The highest growth rate occurs in the summer,with an annual average growth rate of 7.2%during the period from 2014 to 2020.Agricultural emissions dominated NH_(3)VCDs during spring and summer,with high concentrations primarily located in the agricultural areas adjacent to densely populated urban zones.Regions within several large urban areas have been discovered to exhibit relatively stable variations in NH_(3)VCDs.The rise in NH_(3)VCDs within the YRD region was primarily driven by the reduction of acidic gases like SO_(2),as emphasized by GAM modeling and sensitivity tests using the GEOS-Chem model.The concentration changes of acidic gases contribute to over 80%of the interannual variations in NH_(3)VCDs.This emphasizes the crucial role of environmental policies targeting the reduction of these acidic gases.Effective emission control is urgent tomitigate environmental hazards and secondary particulate matter,especially in the northern YRD. 展开更多
关键词 Yangtze River Delta AMMONIA spatiotemporal distribution Driving factors
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Integrated spatiotemporal data mining and DInSAR for improved understanding of subsidence related to groundwater depletion impacts 被引量:1
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作者 Jalal KARAMI Fatemeh BABAEE +1 位作者 Pouya MAHMOUDNIA Mohammad SHARIFI KIA 《Journal of Geographical Sciences》 2025年第3期598-618,共21页
Population growth leads to increased utilization of water resources.One of these resources is groundwater,which has steadily declined each year.The depletion of these resources brings about various environmental chall... Population growth leads to increased utilization of water resources.One of these resources is groundwater,which has steadily declined each year.The depletion of these resources brings about various environmental challenges.The present study aimed to explore the relationship between groundwater fluctuations and land subsidence in the Malayer Plain,Iran,focusing on quantifying subsidence resulting from groundwater extraction.Using Sentinel-1 satellite data(2014–2019)and monthly piezometric measurements(1996–2018),the analysis revealed an average deformation velocity of–6.3 cm yr–1,with accumulated subsidence of–32 cm over the 2014–2019 period.The maximum subsidence rate reached 10.3 cm yr–1 in areas of intensive agricultural activity.A wavelet-PCA spatiotemporal analysis of groundwater fluctuations identified critical multi-scale patterns strongly correlated with subsidence trends.Regression analysis between subsidence rates and groundwater fluctuations at various wavelet decomposition levels explained 75%of the variance(R2=0.75),indicating that intermediate-scale groundwater declines were the primary drivers of subsidence.Furthermore,land use analysis using Landsat data(1999–2021)revealed a 6230-ha increase in irrigated farmland,contributing to heightened groundwater extraction and subsidence rates.These findings highlight the critical need for sustainable groundwater management to mitigate the risks of continued subsidence in the region. 展开更多
关键词 spatiotemporal wavelet-PCA analysis SUBSIDENCE INTERFEROMETRY piezometric data Malayer Plain
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Investigation of spatiotemporal distribution and formation mechanisms of ozone pollution in eastern Chinese cities applying convolutional neural network 被引量:1
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作者 Qiaoli Wang Dongping Sheng +7 位作者 Chengzhi Wu Xiaojie Ou Shengdong Yao Jingkai Zhao Feili Li Wei Li Jianmeng Chen 《Journal of Environmental Sciences》 2025年第2期126-138,共13页
Severe ground-level ozone(O_(3))pollution over major Chinese cities has become one of the most challenging problems,which have deleterious effects on human health and the sustainability of society.This study explored ... Severe ground-level ozone(O_(3))pollution over major Chinese cities has become one of the most challenging problems,which have deleterious effects on human health and the sustainability of society.This study explored the spatiotemporal distribution characteristics of ground-level O_(3) and its precursors based on conventional pollutant and meteorological monitoring data in Zhejiang Province from 2016 to 2021.Then,a high-performance convolutional neural network(CNN)model was established by expanding the moment and the concentration variations to general factors.Finally,the response mechanism of O_(3) to the variation with crucial influencing factors is explored by controlling variables and interpolating target variables.The results indicated that the annual average MDA8-90th concentrations in Zhejiang Province are higher in the northern and lower in the southern.When the wind direction(WD)ranges from east to southwest and the wind speed(WS)ranges between 2 and 3 m/sec,higher O_(3) concentration prone to occur.At different temperatures(T),the O_(3) concentration showed a trend of first increasing and subsequently decreasing with increasing NO_(2) concentration,peaks at the NO_(2) concentration around 0.02mg/m^(3).The sensitivity of NO_(2) to O_(3) formation is not easily affected by temperature,barometric pressure and dew point temperature.Additionally,there is a minimum IRNO_(2) at each temperature when the NO_(2) concentration is 0.03 mg/m^(3),and this minimum IRNO_(2) decreases with increasing temperature.The study explores the response mechanism of O_(3) with the change of driving variables,which can provide a scientific foundation and methodological support for the targeted management of O_(3) pollution. 展开更多
关键词 OZONE spatiotemporal distribution Convolutional neural network Ozone formation rules Incremental reactivity
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Cell communication and relevant signaling pathways in osteogenesis–angiogenesis coupling 被引量:1
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作者 Shuqing Li Xinjia Cai +4 位作者 Jiahe Guo Xiaolu Li Wen Li Yan Liu Mengchun Qi 《Bone Research》 2025年第2期283-306,共24页
Osteogenesis is the process of bone formation mediated by the osteoblasts,participating in various bone-related physiological processes including bone development,bone homeostasis and fracture healing.It exhibits temp... Osteogenesis is the process of bone formation mediated by the osteoblasts,participating in various bone-related physiological processes including bone development,bone homeostasis and fracture healing.It exhibits temporal and spatial interconnectivity with angiogenesis,constructed by multiple forms of cell communication occurring between bone and vascular endothelial cells.Molecular regulation among different cell types is crucial for coordinating osteogenesis and angiogenesis to facilitate bone remodeling,fracture healing,and other bone-related processes.The transmission of signaling molecules and the activation of their corresponding signal pathways are indispensable for various forms of cell communication.This communication acts as a“bridge”in coupling osteogenesis to angiogenesis.This article reviews the modes and processes of cell communication in osteogenesisangiogenesis coupling over the past decade,mainly focusing on interactions among bone-related cells and vascular endothelial cells to provide insights into the mechanism of cell communication of osteogenesis-angiogenesis coupling in different bone-related contexts.Moreover,clinical relevance and applications are also introduced in this review. 展开更多
关键词 fracture healing bone remodeling cell communication ANGIOGENESIS signaling pathways osteogenesis bone formation forms cell communication
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Spatiotemporal influence of driving factors on water conservation in underdeveloped plateau regions: a case in the Yellow River Basin of Sichuan, China 被引量:1
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作者 WANG Xuan MA Lei +5 位作者 LU Heng LIU Chao NIE Ruihua LI Naiwen TAN Xiao YANG Zhengli 《Journal of Mountain Science》 2025年第4期1289-1305,共17页
The Yellow River Basin in Sichuan Province(YRS)is undergoing severe soil erosion and exacerbated ecological vulnerability,which collectively pose formidable challenges for regional water conservation(WC)and sustainabl... The Yellow River Basin in Sichuan Province(YRS)is undergoing severe soil erosion and exacerbated ecological vulnerability,which collectively pose formidable challenges for regional water conservation(WC)and sustainable development.While effectively enhancing WC necessitates a comprehensive understanding of its driving factors and corresponding intervention strategies,existing studies have largely neglected the spatiotemporal heterogeneity of both natural and socio-economic drivers.Therefore,this study explored the spatiotemporal heterogeneity of WC drivers in YRS using multi-scale geographically weighted regression(MGWR)and geographically and temporally weighted regression(GTWR)models from an eco-hydrological perspective.We discovered that downstream regions,which are more developed,achieved significantly better WC than upstream regions.The results also demonstrated that the influence of temperature and wind speed is consistently dominant and temporally stable due to climate stability,while the influence of vegetation shifted from negative to positive around 2010,likely indicating greater benefits from understory vegetation.Economic growth positively impacted WC in upstream regions but had a negative effect in the more developed downstream regions.These findings highlight the importance of targeted water conservation strategies,including locally appropriate revegetation,optimization of agricultural and economic structures,and the establishment of eco-compensation mechanisms for ecological conservation and sustainable development. 展开更多
关键词 Water conservation Multi-scale Geographically Weighted Regression Geographically and Temporally Weighted Regression The Yellow River Basin in Sichuan Province spatiotemporal variation
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Spatiotemporal Resilience of IoT-Enabled Unmanned System of Systems
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作者 Hongyan Dui Huanqi Zhang +1 位作者 Shaomin Wu Min Xie 《Engineering》 2025年第11期355-369,共15页
As advancements in the Internet of Things(IoT)and unmanned technologies continues to progress,the development of unmanned system of systems(USS)has reached unprecedented levels.While prior research has predominantly e... As advancements in the Internet of Things(IoT)and unmanned technologies continues to progress,the development of unmanned system of systems(USS)has reached unprecedented levels.While prior research has predominantly examined temporal variations in USS resilience,spatial changes remain underexplored.However,USS may involve kinetic engagements and frequent spatial changes during mission execution,affecting signal interference in data layer communications.Although time-dependent factors primarily govern mission effectiveness of the USS,spatial factors influence the transmission stability of the data layer.Consequently,assessing spatiotemporal variations in USS performance is critical.To address these challenges,this study introduces a spatiotemporal resilience assessment framework,which evaluates USS resilience across both temporal and spatial dimensions.Furthermore,we propose a spatiotemporal resilience optimization scheme that enhances system adaptability throughout the mission lifecycle,with a particular emphasis on prevention and recovery strategies.Finally,we validate the validity of the proposed concepts and methods with a case study featuring a regular hexagonal deployment of USS.The results show that the spatiotemporal resilience can better reflect the spatial change characteristics of USS,and the proposed optimization strategy improves the prevention spatiotemporal resilience,recovery spatiotemporal resilience,and entire-process spatiotemporal resilience of USS by 0.22%,8.39%,and 11.29%,respectively. 展开更多
关键词 spatiotemporal performance spatiotemporal resilience Unmanned equipment Importance measure
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A Generative Adversarial Network with an Attention Spatiotemporal Mechanism for Tropical Cyclone Forecasts
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作者 Xiaohui LI Xinhai HAN +5 位作者 Jingsong YANG Jiuke WANG Guoqi HAN Jun DING Hui SHEN Jun YAN 《Advances in Atmospheric Sciences》 2025年第1期67-78,共12页
Tropical cyclones(TCs)are complex and powerful weather systems,and accurately forecasting their path,structure,and intensity remains a critical focus and challenge in meteorological research.In this paper,we propose a... Tropical cyclones(TCs)are complex and powerful weather systems,and accurately forecasting their path,structure,and intensity remains a critical focus and challenge in meteorological research.In this paper,we propose an Attention Spatio-Temporal predictive Generative Adversarial Network(AST-GAN)model for predicting the temporal and spatial distribution of TCs.The model forecasts the spatial distribution of TC wind speeds for the next 15 hours at 3-hour intervals,emphasizing the cyclone's center,high wind-speed areas,and its asymmetric structure.To effectively capture spatiotemporal feature transfer at different time steps,we employ a channel attention mechanism for feature selection,enhancing model performance and reducing parameter redundancy.We utilized High-Resolution Weather Research and Forecasting(HWRF)data to train our model,allowing it to assimilate a wide range of TC motion patterns.The model is versatile and can be applied to various complex scenarios,such as multiple TCs moving simultaneously or TCs approaching landfall.Our proposed model demonstrates superior forecasting performance,achieving a root-mean-square error(RMSE)of 0.71 m s^(-1)for overall wind speed and 2.74 m s^(-1)for maximum wind speed when benchmarked against ground truth data from HWRF.Furthermore,the model underwent optimization and independent testing using ERA5reanalysis data,showcasing its stability and scalability.After fine-tuning on the ERA5 dataset,the model achieved an RMSE of 1.33 m s^(-1)for wind speed and 1.75 m s^(-1)for maximum wind speed.The AST-GAN model outperforms other state-of-the-art models in RMSE on both the HWRF and ERA5 datasets,maintaining its superior performance and demonstrating its effectiveness for spatiotemporal prediction of TCs. 展开更多
关键词 tropical cyclones spatiotemporal prediction generative adversarial network attention spatiotemporal mechanism deep learning
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Mg–Sc alloy promotes angiogenesis–osteogenesis coupling and ameliorates steroid-induced osteonecrosis of the femoral head
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作者 Wen-Hao Liang Wan-Shun Wang +7 位作者 Peng Gao Ze-Feng Lin Ling-Ling Chen Yang-Yang Yu Bei-Chen Zhang Bill Subin Xiao-Na Wu Tao Zhang 《Rare Metals》 2025年第9期6707-6729,共23页
Steroid-induced osteonecrosis of the femoral head (SONFH) is a severe bone disorder that was clinically treated by core decompression (CD) combined with bone grafting.However,the clinical outcome of this therapy for S... Steroid-induced osteonecrosis of the femoral head (SONFH) is a severe bone disorder that was clinically treated by core decompression (CD) combined with bone grafting.However,the clinical outcome of this therapy for SONFH is usually unsatisfactory.Magnesium (Mg) is a biodegradable material reported as an ideal orthopedic implant.The Mg^(2+)released from its degradation is considered an effective factor for bone tissue formation,but the rapid degradation rate limited its application.Here,we reported a magnesiumDscandium (MgDSc) alloy for promoting bone regeneration in SONFH.We discovered that MgDSc alloy with satisfied corrosion resistance,antiapoptosis,angiogenic,and osteogenic properties in vitro,could facilitate osteogenic differentiation by activating the Wnt/β-catenin signaling pathway.In the clinically relevant SONFH model,CD combined with suitable MgDSc alloy implantation promoted angiogenesisDosteogenesis coupling and alleviated osteonecrosis.We observed fewer apoptotic osteocytes and empty bone lacunae,but more blood vessels and new bone formation in the Mg-Sc alloy implanted CD tunnel region compared with CD-treated SONFH rabbits.Properly degraded MgDSc alloy maintains high structural integrity and provides reliable mechanical support for the osteonecrotic femoral head,which is conducive to further clinical translation. 展开更多
关键词 Mg-Sc alloy OSTEONECROSIS ANTI-APOPTOSIS ANGIOGENESIS osteogenesis
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An assessment of atmospheric concentrations and spatiotemporal variation of BTEX and associated pollutants in India
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作者 Sruthi Jayaraj S.M.Shiva Nagendra 《Journal of Environmental Sciences》 2025年第4期230-245,共16页
Benzene,toluene,ethylbenzene,and xylene(BTEX)pollution poses a serious threat to public health and the environment because of its respiratory and neurological effects,carcinogenic properties,and adverse effects on air... Benzene,toluene,ethylbenzene,and xylene(BTEX)pollution poses a serious threat to public health and the environment because of its respiratory and neurological effects,carcinogenic properties,and adverse effects on air quality.BTEX exposure is a matter of grave concern in India owing to the growing vehicular and development activities,necessitating the assessment of atmospheric concentrations and their spatial variation.This paper presents a comprehensive assessment of ambient concentrations and spatiotemporal variations of BTEX in India.The study investigates the correlation of BTEX with other criteria pollutants andmeteorological parameters,aiming to identify interrelationships and diagnostic indicators for the source characterization of BTEX emissions.Additionally,the paper categorizes various regions in India according to the Air Quality Index(AQI)based on BTEX pollution levels.The results reveal that the northern zone of India exhibits the highest levels of BTEX pollution compared to central,eastern,and western regions.In contrast,the southern zone experiences the least pollution with BTEX.Seasonal analysis indicates that winter and postmonsoon periods,characterized by lower temperatures,are associated with higher BTEX levels due to the accumulation of localized emissions.When comparing the different zones in India,high traffic emissions and localized activities,such as solvent use and solvent evaporation,are found to be the primary sources of BTEX.The findings of the current study aid in source characterization and identification,and better understanding of the region’s air quality problems,which helps in the development of focused BTEX pollution reduction and control strategies. 展开更多
关键词 VOCS BTEX INDIA AQI spatiotemporal variation
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Spatiotemporal distribution and diversity of microplastics in the sediment of beaches in Xiamen City,China
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作者 Fengrun WU Xueyan LI +1 位作者 Chengyi ZHANG Tao WANG 《Journal of Oceanology and Limnology》 2025年第2期396-405,共10页
Coastal ecosystems are plagued by high levels of microplastic pollution.Conducting baseline surveys is crucial to comprehend the distribution and influencing factors of this pollution.The present study investigates th... Coastal ecosystems are plagued by high levels of microplastic pollution.Conducting baseline surveys is crucial to comprehend the distribution and influencing factors of this pollution.The present study investigates the spatiotemporal variation and diversity of microplastic on the coastal beaches in Xiamen City,China,considering the combined effects of seasons,human activities,and physicochemical properties of sediments.It is detected that the abundance of microplastics in Xiamen beaches was 0.271±0.01 items/g.The abundance of microplastics in dry season was significantly higher than in rainy season.In terms of spatial variation,the beaches that attracted a larger number of tourists exhibited significantly higher microplastic abundance.The temporal pattern of microplastic distribution on different beaches varied greatly due to region-specific human activities(e.g.,mangrove restoration project)and sedimentary properties(e.g.,bulk density).When the assemblage of microplastics in the coastal area was viewed as a biological community,the Shannon-Wiener index and Pielou's index were higher in rainy season and in the beaches with high intensity of tourist activities,which suggests that the human activities and the surface runoff may contribute to the diversity of microplastics on coastal beaches.Future investigations are encouraged to combine controlled experiments and long-term monitoring at multiple scales to elucidate the underlying mechanisms and factors associated with microplastic pollution in coastal zone. 展开更多
关键词 microplastic pollution coastal beaches spatiotemporal variation DIVERSITY
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Biodegradable Mg-Ca/Mg-Cu bilayer membranes with enhanced mechanical,osteogenesis and antibacterial performances for GBR applications
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作者 Yanbo Shan Bo Qiao +12 位作者 Sihui Ouyang Chengao Du Lisheng Zhao Gang Wang Jianting Ye Yingjie Xiong Yu Wei Jiangfeng Song Jia She Jiang Peng Xianhua Chen Fusheng Pan Ning Wen 《Journal of Magnesium and Alloys》 2025年第2期792-809,共18页
Magnesium(Mg)alloys with biodegradability and excellent mechanical properties are in high demand for applications in guided bone regeneration(GBR).However,the clinical application of Mg alloys is hindered by infection... Magnesium(Mg)alloys with biodegradability and excellent mechanical properties are in high demand for applications in guided bone regeneration(GBR).However,the clinical application of Mg alloys is hindered by infection risks and limited osteogenesis.Herein,a structure-functional integrated Mg-Ca/Mg-Cu bilayer membrane was rolled at 150℃through various single-pass reductions by using online heating rolling.The Mg-Cu layer was specifically engineered to exhibit antibacterial properties tailored for gingival tissue,while the Mg-Ca layer was designed to support bone regeneration within the defect cavity.The bilayer membrane demonstrated a flexural yield strength of 421.0 MPa and a modulus of 58.6 GPa,indicating exceptional deformation resistance.Furthermore,it maintained notable structural stability by retaining 86.4%of its volume after 21 days in Hanks'solution.In vitro results revealed that the bilayer membrane exhibited favorable biocompatibility and promoted osteogenesis via the synergetic effect of released Mg^(2+)and Ca^(2+)ions.The rapid release of Cu^(2+)ions and the creation of an alkaline environment further improved antibacterial properties,potentially preventing postoperative infections.Additionally,in an in vivo rat calvarial defect model,the membrane demonstrated its capability to stimulate new bone formation.In summary,the Mg-Ca/Mg-Cu bilayer membrane exhibited outstanding mechanical stability,favorable corrosion rates,extraordinary osteogenic and antibacterial activity simultaneously.Consequently,it holds promise as a robust barrier membrane in GBR applications. 展开更多
关键词 BIODEGRADABILITY Magnesium alloy Guided bone regeneration membrane osteogenesis ANTIBACTERIAL
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Oxidative stress-induced circSOD2 inhibits osteogenesis through sponging miR-29b in metabolic-associated fatty liver disease
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作者 Liang-Ping Li Xiao-Ying Chen +7 位作者 Hong-Bo Liu Yi Zhu Min-Jie Xie Yong-Jian Li Meng Luo Mugahed Albahde Hong-Yu Zhang Jian-Ying Lou 《World Journal of Gastroenterology》 2025年第9期68-82,共15页
BACKGROUND Metabolic-associated fatty liver disease(MAFLD)is characterized by lipid accumulation in hepatocytes and is closely associated with oxidative stress.Increasing clinical evidence indicates that MAFLD is link... BACKGROUND Metabolic-associated fatty liver disease(MAFLD)is characterized by lipid accumulation in hepatocytes and is closely associated with oxidative stress.Increasing clinical evidence indicates that MAFLD is linked to bone metabolic disorders,including osteoporosis.Recent studies indicate that the expression profiles of liver circular RNAs(circRNAs)are altered in MAFLD.However,the effects of these changes on bone metabolism remain poorly understood.AIM To investigate the effects and mechanism of differently expressed circRNAs secreted by the liver on osteogenic differentiation in MAFLD.METHODS RNA sequencing was performed to identify highly expressed circRNAs in the liver,validated by quantitative real-time reverse transcription polymerase chain reaction,and localized using fluorescence in situ hybridization(FISH).A mouse model induced by a high-fat diet was used to simulate MAFLD.RESULTS CircSOD2 was significantly upregulated in liver tissues and primary hepatocytes from subjects with MAFLD.CircSOD2 was induced by oxidative stress and attenuated by antioxidants in the mouse model.In addition,circSOD2 was delivered from hepatocytes to bone marrow mesenchymal stem cells(BMSCs).Furthermore,circSOD2 inhibited the osteogenic differentiation of BMSCs and in vivo bone formation by sponging miR-29b.Moreover,miR-29b inhibition reversed the stimulatory effect of circSOD2 silencing on osteogenic differentiation of BMSCs and in vivo bone formation.Mechanistically,the interaction between circSOD2 and miR-29b confirmed through a luciferase reporter assay and the co-localization in the cytoplasm evidenced by FISH indicated that circSOD2 acted as a sponge for miR-29b.CONCLUSION This study provides a novel mechanism underlying the liver-bone crosstalk,demonstrating that circSOD2 upregulation in hepatocytes,induced by oxidative stress,inhibits osteogenic differentiation of BMSCs by sponging miR-29b.These findings offer a better understanding of the relationship between MAFLD and osteoporosis. 展开更多
关键词 Circular RNAs MICRORNAS Oxidative stress osteogenesis Non-alcoholic fatty liver disease OSTEOPOROSIS
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An Overview of Dynamic Descriptions for Nanoscale Materials in Particulate Photocatalytic Systems from Spatiotemporal Perspectives
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作者 Jiawei Yan Zhidong Wei +4 位作者 Kai Takagi Masaya Motodate Zhi Jiang Chiaki Terashima Wenfeng Shangguan 《Nano-Micro Letters》 2025年第8期416-448,共33页
Particulate photocatalytic systems using nanoscale photocatalysts have been developed as an attractive promising route for solar energy utilization to achieve resource sustainability and environmental harmony.Dynamic ... Particulate photocatalytic systems using nanoscale photocatalysts have been developed as an attractive promising route for solar energy utilization to achieve resource sustainability and environmental harmony.Dynamic obstacles are considered as the dominant inhibition for attaining satisfactory energy-conversion efficiency.The complexity in light absorption and carrier transfer behaviors has remained to be further clearly illuminated.It is challenging to trace the fast evolution of charge carriers involved in transfer migration and interfacial reactions within a micro–nano-single-particle photocatalyst,which requires spatiotemporal high resolution.In this review,comprehensive dynamic descriptions including irradiation field,carrier separation and transfer,and interfacial reaction processes have been elucidated and discussed.The corresponding mechanisms for revealing dynamic behaviors have been explained.In addition,numerical simulation and modeling methods have been illustrated for the description of the irradiation field.Experimental measurements and spatiotemporal characterizations have been clarified for the reflection of carrier behavior and probing detection of interfacial reactions.The representative applications have been introduced according to the reported advanced research works,and the relationships between mechanistic conclusions from variable spatiotemporal measurements and photocatalytic performance results in the specific photocatalytic reactions have been concluded.This review provides a collective perspective for the full understanding and thorough evaluation of the primary dynamic processes,which would be inspired for the improvement in designing solar-driven energy-conversion systems based on nanoscale particulate photocatalysts. 展开更多
关键词 Dynamic description Particulate photocatalytic system Nanoscale photocatalyst spatiotemporal characterization
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