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An improved open-top dynamic chambers method for measuring the exchange fluxes of N_(2)O,NO and NH_(3) from farmland
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作者 Minhang Tan Yining Hu +6 位作者 Yifei Song Zixuan Huang Yujing Mu Junfeng Liu Chenglong Zhang Pengfei Liu Yuanyuan Zhang 《Journal of Environmental Sciences》 2026年第1期535-545,共11页
The application of nitrogen fertilizers in agricultural fields can lead to the release of nitrogen-containing gases(NCGs),such as NO_(x),NH_(3) and N_(2)O,which can significantly impact regional atmospheric environmen... The application of nitrogen fertilizers in agricultural fields can lead to the release of nitrogen-containing gases(NCGs),such as NO_(x),NH_(3) and N_(2)O,which can significantly impact regional atmospheric environment and con-tribute to global climate change.However,there remain considerable research gaps in the accurate measurement of NCGs emissions from agricultural fields,hindering the development of effective emission reduction strategies.We improved an open-top dynamic chambers(OTDCs)system and evaluated the performance by comparing the measured and given fluxes of the NCGs.The results showed that the measured fluxes of NO,N_(2)O and NH_(3)were 1%,2%and 7%lower than the given fluxes,respectively.For the determination of NH_(3) concentration,we employed a stripping coil-ion chromatograph(SC-IC)analytical technique,which demonstrated an absorption efficiency for atmospheric NH_(3) exceeding 96.1%across sampling durations of 6 to 60 min.In the summer maize season,we utilized the OTDCs system to measure the exchange fluxes of NO,NH_(3),and N_(2)O from the soil in the North China Plain.Substantial emissions of NO,NH_(3) and N_(2)O were recorded following fertilization,with peaks of 107,309,1239 ng N/(m^(2)·s),respectively.Notably,significant NCGs emissions were observed following sus-tained heavy rainfall one month after fertilization,particularly with NH_(3) peak being 4.5 times higher than that observed immediately after fertilization.Our results demonstrate that the OTDCs system accurately reflects the emission characteristics of soil NCGs and meets the requirements for long-term and continuous flux observation. 展开更多
关键词 Open-top dynamic chambers Nitrogen-containing gases Soil emissions North China Plain Method evaluation
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Dynamic Changes in the Number of Entomopathogenic Fungal Spores Carried by Pyemotes zhonghuajia
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作者 Litao LI Wenshi ZHAO +3 位作者 Haijiao XU Changxin XU Rui JIAO Liming HE 《Asian Agricultural Research》 2025年第12期53-55,共3页
[Objectives]This study aimed to quantitatively investigate the dynamic patterns of spore powder of Metarhizium anisopliae and Beauveria bassiana carried on the body surface of Pyemotes zhonghuajia,providing a theoreti... [Objectives]This study aimed to quantitatively investigate the dynamic patterns of spore powder of Metarhizium anisopliae and Beauveria bassiana carried on the body surface of Pyemotes zhonghuajia,providing a theoretical basis for optimizing synergistic biological control strategies utilizing natural enemies and pathogens.[Methods]Under laboratory conditions,the spore load on mites after crawling on a spore-powder-coated surface for different durations(0-4 h),and the spore shedding after crawling on a clean surface for different durations(0-4 h)post-loading were measured.[Results]The spore load of mites for both fungi increased with crawling time,but exhibited distinct kinetic patterns.The load of M.anisopliae spores peaked at 2 h(6.86×104 spores/mite)and then decreased significantly;whereas the load of B.bassiana spores continued to increase to a maximum(12.83×104 spores/mite)within 4 h,with the rate of increase slowing significantly after 2 h.During the shedding phase,the number of both types of spores decreased with crawling time.After 4 h,the residual amount of B.bassiana spores(3.18×104 spores/mite)was significantly higher than that of M.anisopliae(2.51×104 spores/mite).[Conclusions]The process of P.zhonghuajia carrying entomopathogenic fungal spores exhibits significant temporal dynamics and species specificity.The findings identify key time points for spore loading and shedding,providing crucial parameters for determining the optimal pre-release"loading"duration and assessing the mites sustained dispersal capacity in the field,which holds significant importance for advancing the application of synergistic biological control technology. 展开更多
关键词 Pyemotes zhonghuajia Entomopathogenic fungi Vector behavior Biological control dynamic changes
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Dynamic Changes of Vegetation and Its Influences in Forest-grassland Ecotone of Ili Region of Xinjiang from the Concept of Ecological Environment
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作者 Liping ZHANG Haiyan MA +2 位作者 Aihong FU Asiya Manlike Ainiwan Aimaier 《Asian Agricultural Research》 2025年第4期10-13,共4页
[Objectives] To analyze the dynamic changes of maximum vegetation coverage in Ili River Basin from 2006 to 2020,and to explore the vegetation change and its influencing factors in the forest-grassland ecotone of Ili r... [Objectives] To analyze the dynamic changes of maximum vegetation coverage in Ili River Basin from 2006 to 2020,and to explore the vegetation change and its influencing factors in the forest-grassland ecotone of Ili region.[Methods] The pixel dichotomy model was used to process the MODIS data and analyze the change of vegetation coverage in the Ili River Basin from 2006 to 2020.[Results] (i)The vegetation coverage in the Ili River Basin increases gradually from west to east,and fluctuates greatly between years.(ii)By monitoring the change rate of the maximum vegetation coverage,it is found that the vegetation coverage of the basin has experienced a process of first decline and then recovery in the past 15 years.(iii)In spatial distribution,vegetation coverage has improved in some regions,while it has deteriorated in others,which may be related to regional climate change and human activities.[Conclusions] The vegetation coverage in the Ili River Basin showed significant spatial and temporal differences during the study period,and its changes were affected by both natural and human factors. 展开更多
关键词 Ecological environment Ili region of Xinjiang Forest-grassland ecotone Vegetation dynamic changes
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Practical Research on the Effective Management of Change Visas and Dynamic Cost Control in the Construction Stage of Construction Projects
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作者 Jinzhu Zheng 《Journal of Architectural Research and Development》 2025年第6期116-123,共8页
Construction project construction stage requires effective change visa management and dynamic cost control.This paper defines both,presents related theories,and details challenges in traditional methods.It then propos... Construction project construction stage requires effective change visa management and dynamic cost control.This paper defines both,presents related theories,and details challenges in traditional methods.It then proposes an integrated model with system architecture,functional modules,and practical strategies like BIM integrated workflows.A case study validates the effectiveness,and future research on AI enhanced change prediction and blockchain based audit trails is suggested. 展开更多
关键词 change visas dynamic cost control Construction projects
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Dynamic psychological vulnerability and adaptation in rheumatoid arthritis:Trajectories,predictors,and interventions
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作者 Xue-Meng Chen Xian Cheng Wei Wu 《World Journal of Psychiatry》 2026年第1期32-46,共15页
Rheumatoid arthritis(RA)patients face significant psychological challenges alongside physical symptoms,necessitating a comprehensive understanding of how psychological vulnerability and adaptation patterns evolve thro... Rheumatoid arthritis(RA)patients face significant psychological challenges alongside physical symptoms,necessitating a comprehensive understanding of how psychological vulnerability and adaptation patterns evolve throughout the disease course.This review examined 95 studies(2000-2025)from PubMed,Web of Science,and CNKI databases including longitudinal cohorts,randomized controlled trials,and mixed-methods research,to characterize the complex interplay between biological,psychological,and social factors affecting RA patients’mental health.Findings revealed three distinct vulnerability trajectories(45%persistently low,30%fluctuating improvement,25%persistently high)and four adaptation stages,with critical intervention periods occurring 3-6 months postdiagnosis and during disease flares.Multiple factors significantly influence psychological outcomes,including gender(females showing 1.8-fold increased risk),age(younger patients experiencing 42%higher vulnerability),pain intensity,inflammatory markers,and neuroendocrine dysregulation(48%showing cortisol rhythm disruption).Early psychological intervention(within 3 months of diagnosis)demonstrated robust benefits,reducing depression incidence by 42%with effects persisting 24-36 months,while different modalities showed complementary advantages:Cognitive behavioral therapy for depression(Cohen’s d=0.68),mindfulness for pain acceptance(38%improvement),and peer support for meaning reconstruction(25.6%increase).These findings underscore the importance of integrating routine psychological assessment into standard RA care,developing stage-appropriate interventions,and advancing research toward personalized biopsychosocial approaches that address the dynamic psychological dimensions of the disease. 展开更多
关键词 Rheumatoid arthritis Psychological vulnerability Disease adaptation ability dynamic changes Mental health
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Dynamic changes of gravity field before the Luding Ms6.8 earthquake and its crustal material migration characteristics
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作者 Qingqing Tan Chongyang Shen +5 位作者 Jiapei Wang Xiong Yang Wen Jin Minghui Zhang Hongbo Tan Guangliang Yang 《Geodesy and Geodynamics》 2025年第2期214-222,共9页
On September 5, 2022, an earthquake of magnitude M_(S)6.8 occurred in Luding County, Sichuan Province.This earthquake occurred at the key part of the southeast-clockwise extrusion of material on the eastern margin of ... On September 5, 2022, an earthquake of magnitude M_(S)6.8 occurred in Luding County, Sichuan Province.This earthquake occurred at the key part of the southeast-clockwise extrusion of material on the eastern margin of the Qinghai Plateau, the Y-shaped confluence of the Xianshuihe, Longmenshan and Anninghe fault zones. In this study, the three-dimensional dynamic crustal density changes in the earthquake area are obtained by the typical gravity change data from 2019 to 2022 before the earthquake and gravity inversion by growing bodies. The results indicate that gravity changes presented an obvious fourquadrant and gradient belt distribution in the Luding area before the earthquake. The threedimensional density horizontal slices show that small density changes occurred at the epicenter in the mid-to-upper crust between 2019.9-2020.9 and 2019.9-2021.9. At the same time, the surrounding areas exhibited a positive and negative quadrant distribution. These observations indicate that the source region was likely in a stable locked state, with locking-in shear forces oriented in the NW and NE directions. From 2021.9 to 2022.8, the epicentral region showed negative density changes, indicating that the source region was in the expansion stage, approaching a near-seismic state. The three-dimensional density vertical slices reveal a southeastward migration of positive and negative densities near the epicenter and on the western of the Xianshuihe Fault Zone, indicating that the material is flowing out to the southeast. The observed local negative density changes at the epicenter along the Longmenshan Fault Zone are likely associated with the NE-oriented extensional stress shown by the seismic source mechanism. The above results can provide a basis for interpreting pre-earthquake gravity and density changes,thereby contributing to the advancement of earthquake precursor theory. 展开更多
关键词 Luding earthquake Gravity changes Three-dimensional density changes Gravity inversion
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Climate change-based dynamic simulation of land use and carbon storage in urban agglomerations of the Yangtze River Economic Belt
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作者 PAN Sipei LIANG Jiale +3 位作者 GUO Jie CHEN Wanxu OU Minghao DE VRIES Walter T 《Journal of Geographical Sciences》 2025年第7期1432-1458,共27页
Low-carbon urban development in China can pave the way to achieve the dualcarbon goal.Exploring how land use changes(LUCs)impact carbon storage(CS)under multi-climate scenarios in different urban agglomerations helps ... Low-carbon urban development in China can pave the way to achieve the dualcarbon goal.Exploring how land use changes(LUCs)impact carbon storage(CS)under multi-climate scenarios in different urban agglomerations helps to formulate differential scientific carbon mitigation policies.In this regard,this study constructs an integrated model of SD-PLUS-InVEST to simulate LUCs and CS changes under multi-climate change-based scenarios(SSP126,SSP245,SSP585)for three major urban agglomerations(3UAs)in the Yangtze River Economic Belt.Results demonstrate that land use demand in the 3UAs changes considerably in each scenario.Construction land in the 3UAs remains the most important growth category for the coming decade,but its increase varies in different scenarios.CS in the Yangtze River Delta Urban Agglomeration(YRDUA)and Mid-Yangtze River Urban Agglomeration(MYRUA)shows a similar downward trend under different scenarios,with scenario SSP245 decreasing the most,to 184,713.526 Tg and 384,459.729 Tg,respectively.CS in the Cheng-Yu(Chengdu-Chongqing)Urban Agglomeration(CYUA)exhibits the opposite upward trend,with scenario SSP126 increasing the most to 153,007.973 Tg.The major cause of CS loss remains the conversion of forest land to construction land in the YRDUA and MYRUA under different scenarios.However,in the CYUA,the conversion of forest land to cultivated land is the major driver of CS loss under scenario SSP126.In contrast,the conversion of cultivated land to construction land dominantly drives CS loss under scenarios SSP245 and SSP585.The conversion of water body to other land use types is the major cause of CS gain in the YRDUA and MYRUA under different scenarios.At the same time,in the CYUA,the driver is the conversion of cultivated land to forest land.These findings demonstrate the significance of the low-carbon development in urban agglomerations at different development stages at home and abroad. 展开更多
关键词 carbon storage land use change climate change SD-PLUS-InVEST model urban agglomerations China
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Coulomb stressing rate changes and seismicity dynamics associated with slow slip events in south-central Alaska
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作者 ShanShan Li XingLei Li Bing Xu 《Earth and Planetary Physics》 2025年第2期289-308,共20页
Two long-term slow slip events(SSEs) in Lower Cook Inlet, Alaska, were identified by Li SS et al.(2016). The earlier SSE lasted at least 9 years with M_(w) ~7.8 and had an average slip rate of ~82 mm/year. The latter ... Two long-term slow slip events(SSEs) in Lower Cook Inlet, Alaska, were identified by Li SS et al.(2016). The earlier SSE lasted at least 9 years with M_(w) ~7.8 and had an average slip rate of ~82 mm/year. The latter SSE, occurring in a similar area, lasted approximately 2 years with M_(w) ~7.2 and an average slip rate of ~91 mm/year. To test whether these SSEs triggered earthquakes near the slow slip area, we calculated the Coulomb stressing rate changes on receiver faults by using two fault geometry definitions: nodal planes of focal mechanism solutions of past earthquakes, and optimally oriented fault planes. Regions in the shallow slab(30–60 km) that experienced a significant increase in the Coulomb stressing rate due to slip by the SSEs showed an increase in seismicity rates during SSE periods. No correlation was found in the volumes that underwent a significant increase in the Coulomb stressing rate during the SSE within the crust and the intermediate slab. We modeled variations in seismicity rates by using a combination of the Coulomb stress transfer model and the framework of rate-and-state friction. Our model indicated that the SSEs increased the Coulomb stress changes on adjacent faults,thereby increasing the seismicity rates even though the ratio of the SSE stressing rate to the background stressing rate was small. Each long-term SSE in Alaska brought the megathrust updip of the SSE areas closer to failure by up to 0.1–0.15 MPa. The volumes of significant Coulomb stress changes caused by the Upper and Lower Cook Inlet SSEs did not overlap. 展开更多
关键词 slow slip events Coulomb stressing rate change seismicity rate change receiver fault rate–state stress transfer model seismogenic zone megathrust failure
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Arctic Ocean Dynamical Downscaling Data for Understanding Past and Future Climate Change
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作者 Qi SHU Qiang WANG +6 位作者 Yan HE Zhenya SONG Gui GAO Hailong LIU Shizhu WANG Rongrong PAN Fangli QIAO 《Advances in Atmospheric Sciences》 2025年第9期1761-1775,共15页
The Arctic is one of Earth’s regions highly susceptible to climate change.However,in situ long-term observations used for climate research are relatively sparse in the Arctic Ocean,and current climate models exhibit ... The Arctic is one of Earth’s regions highly susceptible to climate change.However,in situ long-term observations used for climate research are relatively sparse in the Arctic Ocean,and current climate models exhibit notable biases in Arctic Ocean simulations.Here,we present an Arctic Ocean dynamical downscaling dataset,obtained from the global ocean-sea ice model FESOM2 with a regionally refined horizonal resolution of 4.5 km in the Arctic region,which is driven by bias-corrected surface forcings derived from a climate model.The dataset includes 115 years(1900-2014)of historical simulations and two 86-year future projection simulations(2015-2100)for the SSP2-4.5 and SSP5-8.5 scenarios.The historical simulations demonstrate substantially reduced biases in temperature,salinity and sea-ice thickness compared to CMIP6 climate models.Common biases in the representation of the Atlantic Water layer found in climate model simulations are also markedly reduced in the dataset.Serving as a crucial long-term data source for climate change assessments and scientific research for the Arctic Ocean,this dataset provides valuable information for the scientific community. 展开更多
关键词 Arctic Ocean climate change CMIP6 FESOM2 FIO-ESM
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Dynamic and polarization-independent high-Q guided resonances in metasurfaces with phase change material
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作者 Guozhong Zhang Mimi Zhou +1 位作者 Hong Xiang Dezhuan Han 《Chinese Physics B》 2025年第8期576-582,共7页
Using periodic refractive index perturbations,the Brillouin zone is folded,transforming the guided modes in a metasurface into guided resonances with arbitrarily high quality-factors.The incorporation of phase change ... Using periodic refractive index perturbations,the Brillouin zone is folded,transforming the guided modes in a metasurface into guided resonances with arbitrarily high quality-factors.The incorporation of phase change materials within the metasurface enables dynamic modulation of the guided modes.The system’s symmetry ensures a polarization-independent response under normal incidence.Furthermore,the metasurface exhibits excellent sensing performance,demonstrating its potential for advanced photonic applications. 展开更多
关键词 Brillouin zone folding phase change material guided resonance sensing
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Recyclable,Flexible and Highly Thermally Conductive Phase Change Composites with Dynamic Networks for Thermal Management
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作者 Jun-Xia Guo Shuang-Yu Cai +6 位作者 Xu Han Ye Sun Chun-Lin Li Kai Zheng Yu-Ze Xu Rui-Guang Li Cheng-Jie Li 《Chinese Journal of Polymer Science》 2025年第4期625-639,共15页
Flexible phase change materials(PCMs)have become increasingly critical to address the demand for thermal management in electronic technologies and energy conversion.However,their application remains challenging becaus... Flexible phase change materials(PCMs)have become increasingly critical to address the demand for thermal management in electronic technologies and energy conversion.However,their application remains challenging because of their rigidity,liquid leakage,and insufficient thermal conductivity.Herein,flexible glutamic acid@natural rubber/paraffin wax(PW)/carbon nanotubes-graphene nanoplatelets(GNR/PW/CGNP)phase change composites with high thermal conductivity,excellent shape stability,and recyclability were reported.Zn^(2+)-based dynamic crosslinking was constructed through the reaction of zinc acetate and carboxyl groups on glutamic acid@natural rubber(GNR),which was used as a flexible matrix to physically blend with paraffin wax/carbon nanotubes/graphene nanoplatelets(PW/CGNP)to achieve uniform dispersion of PW/CGNP,continuous thermal conductivity networks,and good encapsulation of PW.The GNR/PW/CGNP composites showed excellent mechanical strength,flexibility,and recycling ability,and effective encapsulation prevented the outflow of melted PW during the phase transition.Also,the phase change enthalpy could attain 111.1 J/g with a higher thermal conductivity of 1.055 W/m K,428%higher than that of pure PW owing to the formation of efficient thermal conductive pathways,which exhibited outstanding thermal management performance and superior temperature control behavior in electronic devices.The developed flexible composite PCMs may open new possibilities for next-generation flexible thermal management electronics. 展开更多
关键词 Phase change composites Mechanical flexibility Shape stability Recycling ability Thermal management
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Understanding the C-C coupling mechanism in electrochemical CO reduction at low CO coverage:Dynamic change in site preference matters
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作者 Zhe Chen Tao Wang 《Chinese Journal of Catalysis》 2025年第2期193-202,共10页
A thoroughly mechanistic understanding of the electrochemical CO reduction reaction(eCORR)at the interface is significant for guiding the design of high-performance electrocatalysts.However,unintentionally ignored fac... A thoroughly mechanistic understanding of the electrochemical CO reduction reaction(eCORR)at the interface is significant for guiding the design of high-performance electrocatalysts.However,unintentionally ignored factors or unreasonable settings during mechanism simulations will result in false positive results between theory and experiment.Herein,we computationally identified the dynamic site preference change of CO adsorption with potentials on Cu(100),which was a previously unnoticed factor but significant to potential-dependent mechanistic studies.Combined with the different lateral interactions among adsorbates,we proposed a new C–C coupling mechanism on Cu(100),better explaining the product distribution at different potentials in experimental eCORR.At low potentials(from–0.4 to–0.6 V_(RHE)),the CO forms dominant adsorption on the bridge site,which couples with another attractively aggregated CO to form a C–C bond.At medium potentials(from–0.6 to–0.8 VRHE),the hollow-bound CO becomes dominant but tends to isolate with another adsorbate due to the repulsion,thereby blocking the coupling process.At high potentials(above–0.8 VRHE),the CHO intermediate is produced from the electroreduction of hollow-CO and favors the attraction with another bridge-CO to trigger C–C coupling,making CHO the major common intermediate for C–C bond formation and methane production.We anticipate that our computationally identified dynamic change in site preference of adsorbates with potentials will bring new opportunities for a better understanding of the potential-dependent electrochemical processes. 展开更多
关键词 Electrochemical CO reduction reaction Lowco coverage dynamic site-preference Potential-dependent C-C coupling Constant-potential density functional theory
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Current status and recent changes of glaciers in Tajikistan
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作者 XU Chunhai LI Zhongqin +6 位作者 HE Zhonghua WANG Feiteng MU Jianxin CHEN Yaning Sheralizoda NAZRIALO Farhod NASRULLOEV Aminjon GULAHMADZODA 《Regional Sustainability》 2026年第1期75-90,共16页
Tajikistan contains the majority of Central Asia’s glaciers,which cover about 6.00%of the national territory;their rapid shrinkage poses a significant threat to regional water resource security.However,glacier monito... Tajikistan contains the majority of Central Asia’s glaciers,which cover about 6.00%of the national territory;their rapid shrinkage poses a significant threat to regional water resource security.However,glacier monitoring in Tajikistan was interrupted after 1991,creating a substantial gap in understanding the current state and temporal evolution of these glaciers.Based on glacier inventory data,in situ measurements,and published literature,this study examined the present status and recent variations of glaciers in Tajikistan through data integration and validation,literature collation and comparative analysis,and the application of Geographic Information System(GIS)spatial analysis techniques.As of 2023,Tajikistan possesses a total of 11,528 glaciers,encompassing an area of 7624.48(±305.58)km2.Small glaciers dominate in number,whereas large glaciers account for the majority of the total area.Over the past two decades,the glacier count has decreased by 2014,and the total area has decreased by 628.98 km2,corresponding to an average annual reduction rate of 0.33%.Regional shrinkage rates range from 4.10%to 22.28%.Glaciers have undergone accelerated mass loss during the past 20 a;only those on the northeastern Pamir Plateau exhibit a weak positive mass balance.Observations of typical monitored glaciers also reveal intensified melting and retreat,consistent with regional trends.In light of the recent acceleration of glacier shrinkage in Tajikistan,focused measures should be implemented to strengthen glacier monitoring,enhance public awareness of glacier preservation,and promote the sustainable development and utilization of glacier tourism.These findings bridge the knowledge gap regarding the spatiotemporal dynamics of Tajikistan’s glaciers over recent decades and provide essential data support for regional water resource management. 展开更多
关键词 Glacier inventory Glacier change Glacier mass balance Climate change TAJIKISTAN
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Long-term leaf nitrogen and phosphorus dynamics and drivers in China's forests under global change
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作者 Chenxi Li Honglin He +6 位作者 Xinyu Zhang Xiaoli Ren Liang Shi Li Zhang Qian Xu Mengyu Zhang Yonghong Zhang 《Forest Ecosystems》 2025年第4期668-676,共9页
The leaf nitrogen(N)to phosphorus(P)ratio(N:P)is a critical indicator of nutrient dynamics and ecosystem function.Investigating temporal variations in leaf N:P can provide valuable insights into how plants adapt to en... The leaf nitrogen(N)to phosphorus(P)ratio(N:P)is a critical indicator of nutrient dynamics and ecosystem function.Investigating temporal variations in leaf N:P can provide valuable insights into how plants adapt to environmental changes and nutrient availability.However,limited research has been conducted on long-term temporal leaf N:P variation over a range of temperature zones.Using long-term monitoring data from the Chinese Ecosystem Research Network(CERN),we investigated temporal changes in leaf N and P stoichiometry for 50 dominant tree species from 10 typical forest sites across temperate and subtropical regions,and identified the underlying mechanisms driving these changes.For both regions combined,leaf P concentration of the 50 dominant tree species decreased(20.6%),whereas leaf N:P increased(52.0%)from 2005 to 2020.Leaf P decreased and leaf N:P increased in 67% and 69% of the tree species,respectively.The leaf N:P increase was primarily driven by the tree species in eastern subtropical forests,where global change factors and soil nutrients explained 68% of leaf N:P variation.The P limitation exhibited by tree species in eastern subtropical forest ecosystems intensified over time,and elevated temperature and CO_(2) levels,coupled with decreased soil available P concentrations,appear to be the main factors driving long-term leaf N:P increases in these forests.Investigating long-term variations in soil nutrients together with global change factors will improve our understanding of the nutrient status of forest ecosystems in the context of global change and will support effective forest ecosystem management. 展开更多
关键词 Leaf nitrogen(N) Leaf phosphorus(P) Leaf N:P Temporal trends Global change factors Soil available phosphorus
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Dynamic response of the ground beneath a high-speed railway based on typical upper Shanghai clays involving water table change
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作者 Jing HU Chengming YE +3 位作者 Juntao JIANG Shujing WU David THOMPSON Xuecheng BIAN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第8期787-800,共14页
A rising water table increases soil water content,reduces soil strength,and amplifies vibrations under identical train loads,thereby posing greater risks to train operations.To investigate this phenomenon,we used a 2.... A rising water table increases soil water content,reduces soil strength,and amplifies vibrations under identical train loads,thereby posing greater risks to train operations.To investigate this phenomenon,we used a 2.5D finite element(FE)model of a coupled vehicle–embankment–ground system based on Biot’s theory.The ground properties were derived from a typical soil profile of the Yangtze River basin,using geological data from Shanghai,China.The findings indicate that a rise in the water table leads to increased dynamic displacements of both the track and the ground.This amplification effect extends beyond the depth of the water table,impacting the entire embankment–foundation cross-section,and intensifies with higher train speeds.However,the water table rise has a limited impact on the critical speed of trains and dominant frequency contents.The dynamic response of the embankment is more significantly affected by water table rises within the subgrade than by those within the ground.When the water table rises into the subgrade,significant excess pore pressure is generated inside the embankment,causing a substantial drop in effective stress.As a result,the stress path of the soil elements in the subgrade approaches the Mohr-Coulomb failure line,increasing the likelihood of soil failure. 展开更多
关键词 dynamic response Excess pore pressures Water table rise High-speed train 2.5D finite element(FE)model
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Efficacy of dynamic interpersonal therapy in improving mentalising in patients with major depressive disorder and the mediating effect of mentalising on changes in depressive symptoms
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作者 Wenhui Jiang Jiayu Yao +4 位作者 Yuan Wang Shanshan Su Ziwei Zheng Yang Yang Jianyin Qiu 《General Psychiatry》 2025年第1期16-25,共10页
Background Dynamic interpersonal therapy(DIT)is a short-term psychodynamic psychotherapy that has been shown to effectively reduce depressive symptoms in patients with major depressive disorder(MDD).In DIT,the depress... Background Dynamic interpersonal therapy(DIT)is a short-term psychodynamic psychotherapy that has been shown to effectively reduce depressive symptoms in patients with major depressive disorder(MDD).In DIT,the depressive symptoms are formulated as responses to impaired mentalisation.DIT aims to alleviate depressive symptoms by improving mentalising.Aims This study aimed to examine the effect of DIT on improving mentalising and the mediating effect of mentalising in changes in depressive symptoms.Methods Outpatients received either DIT combined with antidepressant medication treatment(DIT group)or antidepressant medication treatment alone(ADM group)for 16 weeks.The Hamilton Depression Rating Scale(HAMD),Patient Health Questionnaire(PHQ)and Reflective Functioning Questionnaire(RFQ)were used.The intention-to-treat principle,mixed linear models,multiple imputation,Pearson's correlation analysis and mediation analysis were conducted.The per-protocol principle was used as sensitivity analysis.Results The DIT group had significantly lower HAMD(least-squares(LS)mean difference=-3.756,p<0.001),PHQ(LS mean difference=-4.188,p<0.001),uncertainty about mental states in the RFQ(RFQ-U,LS mean difference=-2.116,p<0.001)and higher certainty about mental states in the RFQ(RFQ-C,LS mean difference=2.214,p=0.028)scores than the ADM group at post-treatment.The change in RFQ-C was marginally significantly correlated with the change in HAMD(r=-0.218,poretao=0.090),The change in RFQ-U was significantly correlated with the change in HAMD(r=-0.269,poroco-0.024)and the change in PHQ(r=-0.43,Peoretceo l<e0.001).When using RFQ-U as the mediating variable and PHQ as the dependent variable,a significant mediating effect was found(p=0.043,95% confidence interval 0.024 to 1.453).Conclusions The DIT group yielded better outcomes compared with the ADM group in reducing depressive symptoms and improving mentalising.Improvements in mentalising were associated with reductions in depressive symptoms.These findings support that mentalising may contribute to the therapeutic effects of DIT in MDD. 展开更多
关键词 alleviate depressive symptoms Mentalising dynamic interpersonal therapy dit improving mentalising improving mentalisingaims reduce depressive symptoms psychodynamic psychotherapy depressive symptoms
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Dynamic changes of spontaneous brain activity in patients after LASIK:a resting-state fMRI study
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作者 Hui Zhang Zi-Song Xu +11 位作者 Jin-Yu Hu Zhen-Zhe Liu Lei Zhong Liang-Qi He Cheng Chen Xiao-Yu Wang Hong Wei Yan-Mei Zeng Qian Ling Xu Chen Yi-Xin Wang Yi Shao 《International Journal of Ophthalmology(English edition)》 2025年第3期487-495,共9页
AIM:To investigate changes in local brain activity after laser assisted in situ keratomileusis(LASIK)in myopia patients,and further explore whether post-LASIK(POL)patients and healthy controls(HCs)can be distinguished... AIM:To investigate changes in local brain activity after laser assisted in situ keratomileusis(LASIK)in myopia patients,and further explore whether post-LASIK(POL)patients and healthy controls(HCs)can be distinguished by differences in dynamic amplitude of low-frequency fluctuations(dALFF)in specific brain regions.METHODS:The resting-state functional magnetic resonance imaging(rs-fMRI)data were collected from 15 myopic patients who underwent LASIK and 15 matched healthy controls.This method was selected to calculate the corresponding dALFF values of each participant,to compare dALFF between the groups and to determine whether dALFF distinguishes reliably between myopic patients after LASIK and HCs using the linear support vector machine(SVM)permutation test(5000 repetitions).RESULTS:dALFF was lower in POL than in HCs at the right precentral gyrus and right insula.Classification accuracy of the SVM was 89.1%(P<0.001).CONCLUSION:The activity of spontaneous neurons in the right precentral gyrus and right insula of myopic patients change significantly after LASIK.SVM can correctly classify POL patients and HCs based on dALFF differences. 展开更多
关键词 laser assisted in situ keratomileusis resting-state functional magnetic resonance imaging dynamic brain activity amplitude of low-frequency fluctuations support vector machine
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MewCDNet: A Wavelet-Based Multi-Scale Interaction Network for Efficient Remote Sensing Building Change Detection
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作者 Jia Liu Hao Chen +5 位作者 Hang Gu Yushan Pan Haoran Chen Erlin Tian Min Huang Zuhe Li 《Computers, Materials & Continua》 2026年第1期687-710,共24页
Accurate and efficient detection of building changes in remote sensing imagery is crucial for urban planning,disaster emergency response,and resource management.However,existing methods face challenges such as spectra... Accurate and efficient detection of building changes in remote sensing imagery is crucial for urban planning,disaster emergency response,and resource management.However,existing methods face challenges such as spectral similarity between buildings and backgrounds,sensor variations,and insufficient computational efficiency.To address these challenges,this paper proposes a novel Multi-scale Efficient Wavelet-based Change Detection Network(MewCDNet),which integrates the advantages of Convolutional Neural Networks and Transformers,balances computational costs,and achieves high-performance building change detection.The network employs EfficientNet-B4 as the backbone for hierarchical feature extraction,integrates multi-level feature maps through a multi-scale fusion strategy,and incorporates two key modules:Cross-temporal Difference Detection(CTDD)and Cross-scale Wavelet Refinement(CSWR).CTDD adopts a dual-branch architecture that combines pixel-wise differencing with semanticaware Euclidean distance weighting to enhance the distinction between true changes and background noise.CSWR integrates Haar-based Discrete Wavelet Transform with multi-head cross-attention mechanisms,enabling cross-scale feature fusion while significantly improving edge localization and suppressing spurious changes.Extensive experiments on four benchmark datasets demonstrate MewCDNet’s superiority over comparison methods:achieving F1 scores of 91.54%on LEVIR,93.70%on WHUCD,and 64.96%on S2Looking for building change detection.Furthermore,MewCDNet exhibits optimal performance on the multi-class⋅SYSU dataset(F1:82.71%),highlighting its exceptional generalization capability. 展开更多
关键词 Remote sensing change detection deep learning wavelet transform MULTI-SCALE
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Mechanisms of Pore-Grain Boundary Interactions Influencing Nanoindentation Behavior in Pure Nickel: A Molecular Dynamics Study
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作者 Chen-Xi Hu Wu-Gui Jiang +1 位作者 Jin Wang Tian-Yu He 《Computers, Materials & Continua》 2026年第1期368-388,共21页
THE mechanical response and deformation mechanisms of pure nickel under nanoindentation were systematically investigated using molecular dynamics(MD)simulations,with a particular focus on the novel interplay between c... THE mechanical response and deformation mechanisms of pure nickel under nanoindentation were systematically investigated using molecular dynamics(MD)simulations,with a particular focus on the novel interplay between crystallographic orientation,grain boundary(GB)proximity,and pore characteristics(size/location).This study compares single-crystal nickel models along[100],[110],and[111]orientations with equiaxed polycrystalline models containing 0,1,and 2.5 nm pores in surface and subsurface configurations.Our results reveal that crystallographic anisotropy manifests as a 24.4%higher elastic modulus and 22.2%greater hardness in[111]-oriented single crystals compared to[100].Pore-GB synergistic effects are found to dominate the deformation behavior:2.5 nm subsurface pores reduce hardness by 25.2%through stress concentration and dislocation annihilation at GBs,whereas surface pores enable mechanical recovery via accelerated dislocation generation post-collapse.Additionally,size-dependent deformation regimes were identified,with 1 nm pores inducing negligible perturbation due to rapid atomic rearrangement,in contrast with persistent softening in 2.5 nm pores.These findings establish atomic-scale design principles for defect engineering in nickel-based aerospace components,demonstrating how crystallographic orientation,pore configuration,and GB interactions collectively govern nanoindentation behavior. 展开更多
关键词 Pure nickel NANOINDENTATION molecular dynamics PORE grain boundary
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Back-gate-tuned organic electrochemical transistor with temporal dynamic modulation for reservoir computing
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作者 Qian Xu Jie Qiu +6 位作者 Mengyang Liu Dongzi Yang Tingpan Lan Jie Cao Yingfen Wei Hao Jiang Ming Wang 《Journal of Semiconductors》 2026年第1期118-123,共6页
Organic electrochemical transistor(OECT)devices demonstrate great promising potential for reservoir computing(RC)systems,but their lack of tunable dynamic characteristics limits their application in multi-temporal sca... Organic electrochemical transistor(OECT)devices demonstrate great promising potential for reservoir computing(RC)systems,but their lack of tunable dynamic characteristics limits their application in multi-temporal scale tasks.In this study,we report an OECT-based neuromorphic device with tunable relaxation time(τ)by introducing an additional vertical back-gate electrode into a planar structure.The dual-gate design enablesτreconfiguration from 93 to 541 ms.The tunable relaxation behaviors can be attributed to the combined effects of planar-gate induced electrochemical doping and back-gateinduced electrostatic coupling,as verified by electrochemical impedance spectroscopy analysis.Furthermore,we used theτ-tunable OECT devices as physical reservoirs in the RC system for intelligent driving trajectory prediction,achieving a significant improvement in prediction accuracy from below 69%to 99%.The results demonstrate that theτ-tunable OECT shows a promising candidate for multi-temporal scale neuromorphic computing applications. 展开更多
关键词 neuromorphic computing reservoir computing OECT tunable dynamics trajectory prediction
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