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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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Identification of small impact craters in Chang’e-4 landing areas using a new multi-scale fusion crater detection algorithm
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作者 FangChao Liu HuiWen Liu +7 位作者 Li Zhang Jian Chen DiJun Guo Bo Li ChangQing Liu ZongCheng Ling Ying-Bo Lu JunSheng Yao 《Earth and Planetary Physics》 2026年第1期92-104,共13页
Impact craters are important for understanding the evolution of lunar geologic and surface erosion rates,among other functions.However,the morphological characteristics of these micro impact craters are not obvious an... Impact craters are important for understanding the evolution of lunar geologic and surface erosion rates,among other functions.However,the morphological characteristics of these micro impact craters are not obvious and they are numerous,resulting in low detection accuracy by deep learning models.Therefore,we proposed a new multi-scale fusion crater detection algorithm(MSF-CDA)based on the YOLO11 to improve the accuracy of lunar impact crater detection,especially for small craters with a diameter of<1 km.Using the images taken by the LROC(Lunar Reconnaissance Orbiter Camera)at the Chang’e-4(CE-4)landing area,we constructed three separate datasets for craters with diameters of 0-70 m,70-140 m,and>140 m.We then trained three submodels separately with these three datasets.Additionally,we designed a slicing-amplifying-slicing strategy to enhance the ability to extract features from small craters.To handle redundant predictions,we proposed a new Non-Maximum Suppression with Area Filtering method to fuse the results in overlapping targets within the multi-scale submodels.Finally,our new MSF-CDA method achieved high detection performance,with the Precision,Recall,and F1 score having values of 0.991,0.987,and 0.989,respectively,perfectly addressing the problems induced by the lesser features and sample imbalance of small craters.Our MSF-CDA can provide strong data support for more in-depth study of the geological evolution of the lunar surface and finer geological age estimations.This strategy can also be used to detect other small objects with lesser features and sample imbalance problems.We detected approximately 500,000 impact craters in an area of approximately 214 km2 around the CE-4 landing area.By statistically analyzing the new data,we updated the distribution function of the number and diameter of impact craters.Finally,we identified the most suitable lighting conditions for detecting impact crater targets by analyzing the effect of different lighting conditions on the detection accuracy. 展开更多
关键词 impact craters chang’e-4 landing area multi-scale automatic detection YOLO11 Fusion algorithm
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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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Multi-scale Numerical Simulations for Crack Propagation in NiTi Shape Memory Alloys by Molecular Dynamics-based Cohesive Zone Model
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作者 LI Yunfei WANG Yuancen HE Qinshu 《Journal of Wuhan University of Technology(Materials Science)》 2025年第2期599-609,共11页
The multi-scale modeling combined with the cohesive zone model(CZM)and the molecular dynamics(MD)method were preformed to simulate the crack propagation in NiTi shape memory alloys(SMAs).The metallographic microscope ... The multi-scale modeling combined with the cohesive zone model(CZM)and the molecular dynamics(MD)method were preformed to simulate the crack propagation in NiTi shape memory alloys(SMAs).The metallographic microscope and image processing technology were employed to achieve a quantitative grain size distribution of NiTi alloys so as to provide experimental data for molecular dynamics modeling at the atomic scale.Considering the size effect of molecular dynamics model on material properties,a reasonable modeling size was provided by taking into account three characteristic dimensions from the perspective of macro,meso,and micro scales according to the Buckinghamπtheorem.Then,the corresponding MD simulation on deformation and fracture behavior was investigated to derive a parameterized traction-separation(T-S)law,and then it was embedded into cohesive elements of finite element software.Thus,the crack propagation behavior in NiTi alloys was reproduced by the finite element method(FEM).The experimental results show that the predicted initiation fracture toughness is in good agreement with experimental data.In addition,it is found that the dynamics initiation fracture toughness increases with decreasing grain size and increasing loading velocity. 展开更多
关键词 NiTi shape memory alloys multi-scale numerical simulation crack propagation the cohesive zone model molecular dynamics simulation
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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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Study on the Quantity Dynamic Changes of Heterobacteria and Vibrios in Larvae Industrialized Culture System 被引量:7
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作者 马妍 李健 +2 位作者 王斌 王群 刘淇 《Agricultural Science & Technology》 CAS 2008年第2期116-121,共6页
[ Objective ] The dynamic change of heterobacteria and vibrios in larvae industrialized culture system was studied to provide scientific reference for healthy cultivation of shrimp. [ Method ] The heterobacteria, vibr... [ Objective ] The dynamic change of heterobacteria and vibrios in larvae industrialized culture system was studied to provide scientific reference for healthy cultivation of shrimp. [ Method ] The heterobacteria, vibrios and pathogenic vibrio parahaemolyticus were monitored in larvae industrialized culture system. [ Result] The heterobacteria, vibrios and pathogenic vibrio parahaemolyticus were the most in fertilized eggs of shrimp but the least in nauplius, then their number would increase with growth. During whole rearing period, both boterobacteria in larvae, vibrios in water would increase by one order of magnitude, while both vibrios in larvae and heterobacteria in water would increase by two orders of magnitude. There were many heterobacteria and vibrios but few vibrio parahaemolyticus in living bait. The correlation coefficients between larvae and heterobacteria and vibrios in water were 0. 704 and 0. 840 in culture system respectively, while the correlation among heterobacteria, vibrios in living bait and larvae, water were weak or negative. [ Conclusion ] There was a dynamic relation between water and larvae in rearing period, and restrictly control of culture condition would restrain the occurrence of disease caused by vibrio parahaemolyticus, besides that bacteria number in bait was not obviously correlated with bacteria nubmer in culture system. 展开更多
关键词 Chinese shrimp larvae Heterotrophic bacteria VIBRIO Vibrio parahaemolyticus dynamic change
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Study on Dynamic Changes of Land Utilization and Landscape Layout in Pearl River Estuary 被引量:1
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作者 李静 洪鸿加 +1 位作者 陈志良 彭晓春 《Journal of Landscape Research》 2010年第6期11-15,19,共6页
Taking advantage of remote sensing(RS) technology and geographic information system(GIS) technology to interpret the four periods' data of remote sensing images of Pearl River Estuary in the years of 1990,1995,200... Taking advantage of remote sensing(RS) technology and geographic information system(GIS) technology to interpret the four periods' data of remote sensing images of Pearl River Estuary in the years of 1990,1995,2000,and 2005,the changes in land utilization and landscape layout of Pearl River Estuary have been analyzed with reference to land utilization dynamic model and quantitative method in landscape ecology.Results indicate several points as followings.①Located in the region typical of high-speed economic development,Pearl River Estuary shows noticeable changes in land types and evident spatial temporal difference.During these 15 years,the areas of cultivated land and forests have experienced dramatic decline while the land for construction purposes shows the trend of powerful increase.②On the prospect of variation,landscape metrics have indicated great differences among other landscape pattern indices except for Area-Weighted Mean Patch Fractal Dimension(AWMPFD) especially during the period from 1990 to 1995 which experiences the most obvious changes.③On the prospect of landscape,landscape pattern indices also indicate great changes in the landscape layout of Pearl River Estuary from 1990 to 2005 as well as noticeable increase in the number of patches,and various landscape pattern indices show the increase in the degree of regional landscape fragmentation and increase in diversity. 展开更多
关键词 LAND UTILIZATION dynamic changes LANDSCAPE patte rn PEARL RIVER ESTUARY
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RS and GIS-based Analysis on Dynamic Changes of Landscape Pattern on Urban-rural Fringe——A Case Study of Licheng District, Jinan City of China 被引量:1
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作者 张芬 吴泉源 +1 位作者 张辉 徐燕慧 《Journal of Landscape Research》 2012年第6期42-46,共5页
By using GIS, RS and landscape ecology, LandsatTM (1993 and 2009) and ETM (2001) remote sensing images of Licheng District of Ji’nan City, Shandong Province were interpreted, and dynamic changes of landscape pattern ... By using GIS, RS and landscape ecology, LandsatTM (1993 and 2009) and ETM (2001) remote sensing images of Licheng District of Ji’nan City, Shandong Province were interpreted, and dynamic changes of landscape pattern in the district were analyzed at the levels of class and landscape. The results showed that during the 16 years the landscape pattern in the district had changed significantly. (a) From the perspective of patch category, areas of arable land, woodland and grassland decreased unceasingly, and arable land accounted for the largest reduction from 488.15 km 2 in 1993 down to 324.37 km 2 in 2009, witnessing a reduction rate of 33.56%. But the patch quantity and fragmentation increased, patch connectivity reduced. Spatial pattern of construction land expanded and its area witnessed a significant increase of 147.05%. Patch cohesion index increased and connectivity grew better. (b) From the perspective of overall landscape, patch quantity, contagion and perimeter-area fractal dimension decreased, patch shape became simple, the Shannon’s diversity index, Shannon’s evenness index and splitting index increased, landscape heterogeneity rose. With the rapid social and economic development, landscape pattern will be more and more influenced by human behaviors 展开更多
关键词 LANDSCAPE PATTERN dynamic changes GIS LICHENG DISTRICT of Ji’nan CITY
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Numerical simulation of dynamic Coulomb stress changes induced by M6.5 earthquake in Wuding, Yunnan and its relationship with aftershocks 被引量:6
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作者 虎雄林 吴小平 +3 位作者 杨润海 付虹 胡家富 黄雍 《地震学报》 CSCD 北大核心 2008年第1期26-35,共10页
Based on the discrete wavenumber method, we calculate the fields of dynamic Coulomb rupture stress changes and static stress changes caused by M6.5 earthquake in Wuding, and study their relationship with the subsequen... Based on the discrete wavenumber method, we calculate the fields of dynamic Coulomb rupture stress changes and static stress changes caused by M6.5 earthquake in Wuding, and study their relationship with the subsequent after- shocks. The results show that the spatial distribution patterns of the positive region of dynamic stress peak value and static stress peak value are similarly asymmetric, which are basically identical with distribution features of aftershock. The dynamic stress peak value and the static stress in the positive region are more than 0.1 MPa and 0.01 MPa of the triggering threshold, respectively, which indicates that the dynamic and static stresses are helpful for the occurrence of aftershock. This suggests that both influences of dynamic and static stresses should be con- sidered other than only either of them when studying aftershock triggering in near field. 展开更多
关键词 武定地震 动态库仑破裂应力变化 余震 动态应力触发
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Effect of Combined Application of Manure and Chemical Fertilizer on the Dynamic Changes of Purple Soil Nutrient and Soil Enzyme Activities
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作者 施娴 袁玲 《Agricultural Science & Technology》 CAS 2011年第5期765-767,775,共4页
[Objective] The aim was to study the effects of combined of manure and fertilizer on the content of nutrients in purplish soil as well as release dynamics of enzyme activities.[Method] The effects of manure and fertil... [Objective] The aim was to study the effects of combined of manure and fertilizer on the content of nutrients in purplish soil as well as release dynamics of enzyme activities.[Method] The effects of manure and fertilizer application on the content of AOM,NH+4-N and NO-3-N in soil as well as release dynamics of enzyme activities were studied by means of simulation culturing.[Result] In the treatments of combined application of simulation culture experiment,the content of active organic matters,NH+4-N,NO-3-N and soil enzyme activities changed dynamically,which showed a shape of inverted "S" with two or more peaks.Compared with the treatment of fertilization,their peaks were relatively flat and occurred relatively late,while the treatment of fertilization had only one but the highest peak.The content of active organic matter came to top around 10 d in the order of cow5fertilizer5pig5fertilizer5cow manurepig manurefertilizer Ⅰfertilizer Ⅱ;the activity of urease came to top around 10 d in all treatments and in the order of pig manurecow5fertilizer5cow manurefertilizer Ⅰfertilizer Ⅱpig5fertilizer5.The activity of saccharase was in the order of pig5fertilizer5pig manurecow5fertilizer5cow manureCKfertilizer Ⅱfertilizer Ⅰ.[Conclusion] The study could provide the theoretical basis for reasonable application of manure and fertilizer. 展开更多
关键词 MANURE Soil nutrients Soil enzyme activities dynamic changes
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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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A Nonlinear Multi-Scale Interaction Model for Atmospheric Blocking:A Tool for Exploring the Impact of Changing Climate on Mid-to-High Latitude Weather Extremes 被引量:1
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作者 Dehai LUO Wenqi ZHANG Binhe LUO 《Advances in Atmospheric Sciences》 2025年第10期2018-2035,共18页
A nonlinear multi-scale interaction(NMI)model was proposed and developed by the first author for nearly 30 years to represent the evolution of atmospheric blocking.In this review paper,we first review the creation and... A nonlinear multi-scale interaction(NMI)model was proposed and developed by the first author for nearly 30 years to represent the evolution of atmospheric blocking.In this review paper,we first review the creation and development of the NMI model and then emphasize that the NMI model represents a new tool for identifying the basic physics of how climate change influences mid-to-high latitude weather extremes.The building of the NMI model took place over three main periods.In the 1990s,a nonlinear Schr?dinger(NLS)equation model was presented to describe atmospheric blocking as a wave packet;however,it could not depict the lifetime(10-20 days)of atmospheric blocking.In the 2000s,we proposed an NMI model of atmospheric blocking in a uniform basic flow by making a scale-separation assumption and deriving an eddyforced NLS equation.This model succeeded in describing the life cycle of atmospheric blocking.In the 2020s,the NMI model was extended to include the impact of a changing climate mainly by altering the basic zonal winds and the magnitude of the meridional background potential vorticity gradient(PVy).Model results show that when PVy is smaller,blocking has a weaker dispersion and a stronger nonlinearity,so blocking can be more persistent and have a larger zonal scale and weaker eastward movement,thus favoring stronger weather extremes.However,when PVy is much smaller and below a critical threshold under much stronger winter Arctic warming of global warming,atmospheric blocking becomes locally less persistent and shows a much stronger westward movement,which acts to inhibit local cold extremes.Such a case does not happen in summer under global warming because PVy fails to fall below the critical threshold.Thus,our theory indicates that global warming can render summer-blocking anticyclones and mid-to-high latitude heatwaves more persistent,intense,and widespread. 展开更多
关键词 nonlinear Schrödinger equation nonlinear multi-scale interaction model of atmospheric blocking meridional background potential vorticity gradient climate change mid-to-high latitude weather extremes
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Dynamic Changes of Nitrogen in Saline-alkaline Paddy Field and Its Potential Environmental Impacts 被引量:1
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作者 叶洁琼 袁瑞霞 +1 位作者 王兆慧 柳建设 《Agricultural Science & Technology》 CAS 2011年第3期443-446,460,共5页
[Objective] The paper was to study the dynamic changes of nitrogen in saline-alkaline paddy field and its potential environment impacts. [Method] With typical sodic saline-alkaline paddy fields of Songnen Plain as stu... [Objective] The paper was to study the dynamic changes of nitrogen in saline-alkaline paddy field and its potential environment impacts. [Method] With typical sodic saline-alkaline paddy fields of Songnen Plain as study object,field test method was used to explore the dynamic changes was strong alkof nitrogen in paddy field of the region and its potential impact on environment. [Result] The soil in test regionaline with high CEC and C/N ratios,as well as poor preserving capacity of fertilizer. During the two-year field experiment,the indicators of salinization fluctuated. Initially,the concentrations of total nitrogen and ammonia nitrogen reached their maximum values,then decreased over time as a result of heavy rain. The maximum of nitrate concentration appeared later than those of total nitrogen and ammonia nitrogen. Ammonia volatilization accounted for 18.9%-28.8% of the nitrogen loss. The total nitrogen concentration in surface water was higher than the national Class Ⅲ surface water environmental quality standard. The concentration of ammonia from the recession flow of agricultural field was considerably high,which would potentially threaten the fishery in the downstream of Chagan Lake. [Conclusion] The study provided theoretical basis for saline-alkaline soil management and conservation of water and fishery resources. 展开更多
关键词 Saline-alkaline soil NITROGEN dynamic changes Potential environmental impact
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Dynamic changes in lakes in the Hoh Xil region before and after the 2011 outburst of Zonag Lake 被引量:19
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作者 LIU Wen-hui XIE Chang-wei +6 位作者 ZHAO Lin WU Tong-hua WANG Wu ZHANG Yu-xin YANG Gui-qian ZHU Xiao-fan YUE Guang-yang 《Journal of Mountain Science》 SCIE CSCD 2019年第5期1098-1110,共13页
Zonag, Kusai, Hedin Noel and Yanhu Lakes are independent inland lakes in the Hoh Xil region on the Qinghai-Tibet Plateau. In September2011, Zonag Lake burst after the water level had increased for many years. Floods f... Zonag, Kusai, Hedin Noel and Yanhu Lakes are independent inland lakes in the Hoh Xil region on the Qinghai-Tibet Plateau. In September2011, Zonag Lake burst after the water level had increased for many years. Floods flowed through Kusai and Hedin Noel Lakes into Yanhu Lake; since then, the four small endorheic catchments merged into one larger catchment. This hydrological process caused the rapid shrinkage of Zonag Lake and continuous expansion of Yanhu Lake. In this study,based on satellite images, meteorological data and field investigations, we examined the dynamic changes in the four lakes and analyzed the influencing factors. The results showed that before 2011, the trends in the four lake areas were similar and displayed several stages. The change in the area of Zonag Lake corresponded well to the change in annual precipitation(AP), but the magnitude of the change was less than that of a non-glacier-fed lake. Although increased precipitation was the dominant factor that caused Zonag Lake to expand, increased glacier melting and permafrost thawing due to climate warming also had significant effects. After the 2011 outburst of Zonag Lake, due to the increasing AP and accelerating glacier melting, the increases in water volume of the three lakes were absorbed by Yanhu Lake, and Yanhu Lake expanded considerably. According to the rapid growth rates in water level and lake area, Yanhu Lake is likely to burst in 1-2 years. 展开更多
关键词 dynamic changE LAKE areas Influencing factors GLACIER changE PERMAFROST thawing Zonag LAKE
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Dynamic changes of behaviors, dentate gyrus neurogenesis and hippocampal miR-124 expression in rats with depression induced by chronic unpredictable mild stress 被引量:15
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作者 Yun-Ling Huang Ning-Xi Zeng +5 位作者 Jie Chen Jie Niu Wu-Long Luo Ping Liu Can Yan Li-Li Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第6期1150-1159,共10页
The depression-like behavior phenotype,neurogenesis in the dentate gyrus and miR-124 expression in the hippocampus are the focus of current research on the pathogenesis of depression and antidepressant therapy.The pre... The depression-like behavior phenotype,neurogenesis in the dentate gyrus and miR-124 expression in the hippocampus are the focus of current research on the pathogenesis of depression and antidepressant therapy.The present study aimed to clarify the dynamic changes of depression-like behavior,dentate gyrus neurogenesis and hippocampal miR-124 expression during depression induced by chronic stress to reveal pathological features at different stages of depression and to further provide insight into depression treatment.Chronic unpredictable mild stress depression models were established by exposing Sprague-Dawley rats to various mild stressors,including white noise,thermal swimming,stroboscopic illumination,soiled cages,pairing with three other stressed animals,cold swimming,tail pinch,restraint and water and food deprivation.Chronic unpredictable mild stress model rats underwent dynamic observation from 1 to 8 weeks and were compared with a control group(normal feeding without any stressors).To observe changes in the depression-like behavior phenotype during chronic unpredictable mild stress-induced depression,a sucrose preference test was used to evaluate the degree of anhedonia.An open-field test was used to evaluate locomotor activity and anxiety status.Compared with the control group,chronic unpredictable mild stress rats lost weight but did not have a depression-like behavioral phenotype at 1-4 weeks.Chronic unpredictable mild stress rats presented decreased sucrose preference and locomotor activity at 5-8 weeks.In addition,chronic unpredictable mild stress rats did not have significant anxiety-like behavior during 1-8 weeks of modeling.To observe neurogenesis dysfunctions and changes in neuronal number in the dentate gyrus during chronic unpredictable mild stress-induced depression,markers(DCX and DCX/BrdU)of neural proliferation and differentiation and the neuronal marker NeuN were assessed by immunofluorescence.Compared with the control group,neurogenesis and the neuronal number in the dentate gyrus did not change from 2 to 6 weeks;however,neural proliferation and differentiation in the dentate gyrus decreased,and the number of neurons decreased until the eighth week in the chronic unpredictable mild stress group.Real-time quantitative reverse transcription polymerase chain reaction assays and fluorescence in situ hybridization were used to measure the expression of hippocampal miR-124 during chronic unpredictable mild stress-induced depression.The results showed that the expression of hippocampal miR-124 was unchanged during the first 4 weeks but increased from 5 to 6 weeks and decreased from 7 to 8 weeks compared with the control group.These findings indicate that during chronic unpredictable mild stress-induced depression,the behavioral phenotype,miR-124 expression in the hippocampus,neurogenesis in the dentate gyrus and neuronal numbers showed dynamic changes,which suggested that various pathological changes occur at different stages of depression.All experimental procedures and protocols were approved by the Experimental Animal Ethics Committee of Guangzhou University of Chinese Medicine of China in March 2015. 展开更多
关键词 chronic unpredictable MILD stress model continuous observation DEPRESSION depression-like behavior dynamic changes hippocampus miR-124 NEUROGENESIS DYSFUNCTION NEURONAL loss
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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 changes of ocular biometric parameters:a modified form-deprivation myopia model of young guinea pigs 被引量:6
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作者 Hai-Lan Zhao, Jin Jiang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2011年第5期484-488,共5页
AIM: To evaluate the dynamic ocular biometric changes of a modified form-deprivation myopia model in young guinea pigs. METHODS: The animals were randomly assigned to two groups: the monocularly deprived facemask grou... AIM: To evaluate the dynamic ocular biometric changes of a modified form-deprivation myopia model in young guinea pigs. METHODS: The animals were randomly assigned to two groups: the monocularly deprived facemask group (MDF, with all the right eyes covered, n=24) and the normal control group(free of facemask, n=24). Each group was then equally divided into four subgroups which were followed up for 2, 4, 6 and 8 weeks, respectively. Parameters measured from every eye included refraction, corneal curvature, axial length and the dry weight of sclera at the posterior pole. RESULTS: All the facemasks remained in place during the follow-up. The covered eyes developed myopia with the vitreous chamber lengthening and the dry weight of posterior sclera reduced at each time point compared with the contralateral uncovered (P<0.05 at all time points). The changes had a linear correlation with the deprivation time (P<0.05). There were no significant differences in all the parameters between the uncovered eyes of MDF group and the normal control group (P>0.05 at all time points). CONCLUSION: Monocular form deprivation with the facemask is highly effective and non-invasive in inducing axial myopia in guinea pigs. The axial myopia is mainly caused by the increased vitreous chamber length and the weakened posterior sclera rigidity. The form-deprivation eye didn't interfere with the natural development of the contralateral eye. 展开更多
关键词 dynamic change form-deprivation myopia model guinea pig
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Predictive Values of Postoperative and Dynamic Changes of Inflammation Indexes in Survival of Patients with Resected Colorectal Cancer 被引量:11
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作者 Zi-quan ZHOU Shuo PANG +4 位作者 Xing-chen YU Qi XUE Hong-yu JIANG Xin-jun LIANG Li LIU 《Current Medical Science》 SCIE CAS 2018年第5期798-808,共11页
The aim of the present study was to evaluate the prognostic potential of postoperative scores of inflammation indexes and the dynamic changes of scores before and after tumor resection in colorectal cancer patients.Th... The aim of the present study was to evaluate the prognostic potential of postoperative scores of inflammation indexes and the dynamic changes of scores before and after tumor resection in colorectal cancer patients.The study included 516 colorectal cancer patients with primary colorectal tumor resection.Cox regression was applied to estimate the associations of postoperative and dynamic changes of inflammation indexes with progression-free survival and overall survival.As results,we found that higher postoperative neutrophil to lymphocyte ratio (NLR),neutrophil and monocyte to lymphocyte ratio (NMLR),platelet to lymphocyte ratio (PLR) and systemic immune inflammation index (SII)were associated with shorter progression-free survival.The increased NLR,NMLR,PLR,SII and C-reaction protein (CRP)to albumin (ALB) ratio (CAR)were associated with poor progression-free survival,with HRs (95% CIs)of 1.92 (1.27-2.90),1.46(1.11-2.09),2.10(1.34-3.30),1.81(1.22-2.70)and 1.65(1.03-2.67), respectively.Postoperative NMLR,SII,CAR,and their dynamic changes were also significantly correlated with overall survival,with the HRs (95% CIs)of 2.63(1.30-3.97), 2.44(1.43-4.17),2.74(1.31-5.74),2.08(1.21-3.60),1.97(1.12-3.45)and 2.55(1.21-5.38)respectively.In conclusion,postoperative inflammation indexes and their dynamic changes,particularly for NMLR,SII and CAR are promising prognostic predictors of CRC patients. 展开更多
关键词 COLORECTAL cancer POSTOPERATIVE INFLAMMATION index dynamic change PROGNOSIS
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Dynamic changes of flavonoids in Actinidia valvata leaves at different growing stages measured by HPLC-MS/MS 被引量:1
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作者 DU Qiao-Hui ZHANG Qiao-Yan +3 位作者 HAN Ting JIANG Yi-Ping PENG Cheng XIN Hai-Liang 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2016年第1期66-72,共7页
Flavonoids are a large group of phenolic secondary metabolites havinga wide range of biochemical and pharmacological effects.Quantitative analysis of flavonoid profiles in the genus Actinidia,which has not been intens... Flavonoids are a large group of phenolic secondary metabolites havinga wide range of biochemical and pharmacological effects.Quantitative analysis of flavonoid profiles in the genus Actinidia,which has not been intensively conducted,is useful to a better understanding of the pattern and distribution of flavonoids.In the present work,a liquid chromatography-electrospray ionization-tandem mass spectrometry(LC-ESI-MS/MS)method was developed to profile the flavonoids,which was then used to determine the dynamic change of 17 biologically active flavonoids in the leaves of Actinidia valvata at the main growing stages,including glucuronides and acylated di-and triglycosides of flavonoids.The contents of flavonoid triglycosides were significantly higher than other flavonoids.The highest concentrations of kaemperol glycosides were observed in June,while other flavonoids showed highest concentrations in October.On the other hand,the contents of four isorhamnetin glycosides were increased sharply in September to October.The flavonoid profiles seem to be related to temperature,UV-B,and water deficit.Further studies are required to examine the functions of flavonoids in the Actinidia valvata and the underlying molecular mechanisms of actions. 展开更多
关键词 ACTINIDIA valvata LC—MS/MS FLAVONOIDS dynamic change KAEMPFEROL triglycosides GROWING stage
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Dynamic changes of a typical linear dune in the Tengger Desert 被引量:1
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作者 Zhang, KeCun Kai, KenJi +2 位作者 Qu, JianJun Ling, YuQuan Niu, QingHe 《Journal of Arid Land》 SCIE 2010年第4期272-278,共7页
The dynamical processes of a typical linear dune including morphological features, dune ridge swing range and crest height were investigated at different monitoring periods in the hinterland of Tengger Desert. The res... The dynamical processes of a typical linear dune including morphological features, dune ridge swing range and crest height were investigated at different monitoring periods in the hinterland of Tengger Desert. The results indicated that the development of linear dune depends on not only the northwesterly prevailing wind, but also the winds from northeast and southwest. The dune ridge swayed along its fundamental strike and took on an eastward movement gradually. The original dune strike was NW70° on August 3, 1994, and then changed to NE15° on April 21, 2001. The dune crest increased by 1.8 m longitudinally, which manifested strong wind-blown sand activities in this region. Wind erosion frequently occured at the bottom of sand dune, while sand accumulation appeared on its mid-upper section. The mean wind erosion depth was 25 cm on the bottom of linear dune and the height difference of the control points on the dune’s ridge was 1.13 m. Although the linear dune swayed laterally, the horizontal displacement of its ridge moved eastward 5.8 m averagely. The swing range of the dune crest line is very distinct, with a maximum value of 13.2 m. The highest site on the K-profile swayed on both sides of the dune ridge and the heights were 19.88 m at the control point K5, 19.61 m at K6 and 19.05 m at K7, respectively. The results indicated that the lateral swing of the linear dune was distinct under the northwesterly wind and it moved toward east gradually. 展开更多
关键词 linear sand dune dynamic change morphological feature Tengger Desert
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