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Thornthwaite moisture index and depth of suction change under current and future climate‒An Australian study
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作者 Md Rajibul Karim Bikash Devkota +1 位作者 Md Mizanur Rahman Hoang Bao Khoi Nguyen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1761-1775,共15页
Climate change is one of the major global challenges and it can have a significant influence on the behaviour and resilience of geotechnical structures.The changes in moisture content in soil lead to effective stress ... Climate change is one of the major global challenges and it can have a significant influence on the behaviour and resilience of geotechnical structures.The changes in moisture content in soil lead to effective stress changes and can be accompanied by significant volume changes in reactive/expansive soils.The volume change leads to ground movement and can exert additional stresses on structures founded on or within a shallow depth of such soils.Climate change is likely to amplify the ground movement potential and the associated problems are likely to worsen.The effect of atmospheric boundary interaction on soil behaviour has often been correlated to Thornthwaite moisture index(TMI).In this study,the long-term weather data and anticipated future projections for various emission scenarios were used to generate a series of TMI maps for Australia.The changes in TMI were then correlated to the depth of suction change(H s),an important input in ground movement calculation.Under all climate scenarios considered,reductions in TMI and increases in H s values were observed.A hypothetical design scenario of a footing on expansive soil under current and future climate is discussed.It is observed that a design that might be considered adequate under the current climate scenario,may fail under future scenarios and accommodations should be made in the design for such events. 展开更多
关键词 Climate change Future prediction Thornthwaite moisture index(TMI) Characteristic surface movement Infrastructure resilience
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Changing Characteristics of Comfort Index of Human Body in Bengbu City in the Past 40 Years under the Background of Climate Change
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作者 Lei SHAN Xian ZHANG +2 位作者 Lei TIAN Ranran HE Jingyang CHEN 《Meteorological and Environmental Research》 2024年第2期40-43,共4页
Based on the daily meteorological data of Bengbu City during 1981-2020,the changing characteristics of three elements needed for the calculation of the comfort index of human body(CIHB)were discussed,and daily CIHB wa... Based on the daily meteorological data of Bengbu City during 1981-2020,the changing characteristics of three elements needed for the calculation of the comfort index of human body(CIHB)were discussed,and daily CIHB was classified and discussed.The results show that from 1981 to 2020,annual average temperature tended to increase significantly.Annual average wind speed and relative humidity showed a decreasing trend before 2011 but an increasing trend after 2011.The duration of the four seasons in Bengbu City mainly rose in spring,reduced in winter,declined first and then increased in summer,and rose first and then decreased in autumn.As CIHB was at grades 1 and 9(the most uncomfortable),the three factors had different effects on them.For cold weather,the influence of relative humidity and wind speed on CIHB can not be ignored besides temperature.In hot weather,the influence of temperature was dominant,and the change of annual average temperature could well correspond to the change in the number of very hot days.In the context of climate warming,the number of cold days tended to decline generally,but it was larger in the years with fewer very cold days.Under the background of climate warming,there was no obvious change in the number of days of the overall comfort of human body.The number of hot days was closely related to the duration of summer,and the number of days of grade 8 rose significantly in the years with an increase in the duration of summer. 展开更多
关键词 Climate change Human comfort Comfort index of human body(CIHB)
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Land Use Changes along Rail Traffic Routes in Wuhan City Based on Landscape Indexes
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作者 吴浩 孙钰蓉 +1 位作者 周荣 佗琳 《Journal of Landscape Research》 2009年第10期29-32,60,共5页
Based on analyzing the remote sensing images of Wuhan City in 1998,2002 and 2008,information about the land use changes along rail traffic routes before and after the construction of these routes are extracted,and 9 l... Based on analyzing the remote sensing images of Wuhan City in 1998,2002 and 2008,information about the land use changes along rail traffic routes before and after the construction of these routes are extracted,and 9 landscape indexes are applied to quantitatively study the change trend of its land use pattern.The results show that the construction of rail traffic routes has brought enormous changes to the land use pattern along the routes,say,built-up area has become the dominant type which has been rapidly concentrating into patches;the amounts of small patches,such as grass land,have gradually declined and shown an imbalanced distribution. 展开更多
关键词 LAND use changes LANDSCAPE indexes REMOTE sensing(RS) RAIL TRAFFIC
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Proposal of Landscape Space Transfer Index and Changes of Landscape Area Based on Transfer Matrix——With Yutian County in Xinjiang as a Study Case
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作者 贺凌云 海米提.依米提 蔡永革 《Journal of Landscape Research》 2010年第7期26-29,共4页
The most significant changes of landscape in a certain period are landscape area changes and spatial changes of landscape patches.Based on transfer matrix and total amount change of landscape area,landscape space tran... The most significant changes of landscape in a certain period are landscape area changes and spatial changes of landscape patches.Based on transfer matrix and total amount change of landscape area,landscape space transfer index and landscape area change index were established,and then applied to analyze plain oasis and desert in Yutian County,Xinjiang Uyghur Nationality Autonomous Region,the results showed that landscape space transfer in this region was drastic,but total landscape area changed only slightly,thus space transfer index was much higher than area change index,which indicated that landscapes in arid area were given with particular spatial undulant features and sensitivity,while man-made landscapes(artificial oasis) are stable and expanding to some extent.With landscape space transfer index as the comprehensive indicator,space transfer intensity of landscape within a certain period can be demonstrated,which is favorable for the comparison of landscape change intensity among different types and within different periods,in addition,some macroscopic change features of landscapes can also be reflected by comprehensively analyzing landscape space transfer index and landscape area change index. 展开更多
关键词 ARID area LANDSCAPE Space TRANSFER index Area change index
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Demographic changes in China’s forests from 1998 to 2018 被引量:2
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作者 Yanli Dong Evgenios Agathokleous +1 位作者 Shirong Liu Zhen Yu 《Forest Ecosystems》 SCIE CSCD 2023年第1期82-91,共10页
Background: Tree demography is an essential indicator of various forest ecosystem services, and understanding its changes is critical for the sustainable management of forests. During the past four decades, China impl... Background: Tree demography is an essential indicator of various forest ecosystem services, and understanding its changes is critical for the sustainable management of forests. During the past four decades, China implemented unprecedented forest restoration projects, which altered tree demography by increasing the number of trees and introducing new species. However, it remains unclear how species composition has changed in China in response to the past forest restoration and demographical processes.Methods: We applied Forest Stability Index(FSI) and the relative change of FSI(%FSI) to describe the population dynamics of tree species and structure in China since 1998, using field-survey data collected from over 200,000plot-records from the 6th to 9th National Forest Inventories(NFIs).Results: The overall populations of both natural and planted forests have grown rapidly from 1998 to 2018, while the range of changes in the relative tree density was more variable for natural forests(ranging from-8.53% to42.46%) than for planted forests(ranging from-1.01% to 13.31%). The populations declined only in some of the tree species, including Betula platyphylla, Ulmus pumila, and Robinia pseudoacacia. In contrast, the populations of trees in the largest size-class either remained stable or expanded.Conclusions: Tree density of China?s forests(both natural and planted forests) generally expanded and the overall populations increased in most size classes, with greater increases occurred in planted forests. In contrasting to the global decline trends of large diameter trees, here we found no apparent decline for trees in the largest size-class in China, highlighting China?s success in improving forest health and forest adaptations to climate change. We advocate for more studies to reveal the mechanisms of the changes in tree demography, which will help to improve forest ecosystem services such as the carbon sequestration capacity. 展开更多
关键词 Tree demography Forest stability index(FSI) Relative change of FSI(%FSI) Relative density Tree species Tree size-class
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Secular Changes on the Distribution of Body Mass Index among Chinese Children and Adolescents, 1985-2010 被引量:9
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作者 JI Cheng Ye CHEN Tian Jiao SUN Xiao 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第7期520-530,共11页
Objective To analyze the change in Body Mass Index (BMI) distribution among Chinese children and adolescents for the development of more effective intervention for childhood obesity. Methods Data on the national stu... Objective To analyze the change in Body Mass Index (BMI) distribution among Chinese children and adolescents for the development of more effective intervention for childhood obesity. Methods Data on the national students' constitution and health survey between 1985 and 2010 was used for this study. Subjects were students aged 7-18 randomly selected from 30 provinces in China. BMI for-age curves were developed by LMS method, and the trend of BMI distribution was determined by comparing the upper BMI percentiles and analyzing the skew shift of distribution between 2985 and 2010. Results An overall positive swift trend of BMI between 1985 and 2010 was observed among the Chinese school-age children and adolescents. The average median of the BMI increased from 16.8 and 17.0 ks/m2 to 18.2 and 17.9 kg/m2 in 25 years, with increments 0.56 and 0.36 kg/m2 per decade for males and females, respectively. The more obvious increments were found at the high BMI. The total increments of BMI in this period were 4.03 and 2.20 kg/m2 at the 85th, 6.24 and 3.57 kg/m2 at the 95th, and 6.99 and 4.27 kg/m2 at the 97th percentiles, for males and females, respectively. Conclusion Obvious increments were observed at high BMI of the Chinese children and adolescents. More effective interventions should be taken for control and prevention of obesity and its health consequence for these subgroups. It is necessary to establish a risk-complex system consisting of the identification of BMI scope, the screen of the disease risk factors and the assessment of excessive adiposity. 展开更多
关键词 Body mass index OBESITY Chinese School-age children Secular growth changes
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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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Early Cretaceous Climate Changes Recorded in Magnetic Susceptibility and Color Index Variations of the Lower Liupanshan Group, Central China 被引量:3
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作者 DAI Shuang ZHU Qiang +9 位作者 HUANG Yongbo DA SILVA Anne-Christine ZHAO Jie LIU Junwei KONG Li PENG Dongxiang LUO Lingling YAN Ningyun WANG Wenjie ZHANG Xiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第3期1011-1023,共13页
This study carried out comprehensive analysis on sedimentology, magnetic susceptibility (7of) and color data of the continental sediments of the Liupanshan Group in Central China so as to obtain climatic change info... This study carried out comprehensive analysis on sedimentology, magnetic susceptibility (7of) and color data of the continental sediments of the Liupanshan Group in Central China so as to obtain climatic change information during the 129.14-122.98 Ma interval. Based on the results of the Xlf and of the redness (a*), the section can be divided into two segments: (1) 129.14-126.3 Ma, with the lowest Xlf values and strongly variable relatively high values of redness and (2) 126.3-122.98 Ma, with high Elf values and relatively low redness. Analysis of the lithology and facies as well as the magnetic minerals and their contents points to a detrital origin of the magnetic minerals and this allow us to interpret the relationship between magnetic susceptibility variations and climate changes. Our study shows that the climate was significantly dry and hot during the whole studied interval although the interval between 126.3 Ma and 122.98 was a little bit cooler with increased humidity. 展开更多
关键词 magnetic susceptibility color index climate change Liupanshan Group Early Cretaceous
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Applying the Global Disturbance Index for Detecting Vegetation Changes in Lao Tropical Forests 被引量:3
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作者 Chittana Phompila Megan Lewis +1 位作者 Kenneth Clarke Bertram Ostendorf 《Advances in Remote Sensing》 2015年第1期73-82,共10页
Land cover change is a major challenge for many developing countries. Spatiotemporal information on this change is essential for monitoring global terrestrial ecosystem carbon, climate and biosphere exchange, and land... Land cover change is a major challenge for many developing countries. Spatiotemporal information on this change is essential for monitoring global terrestrial ecosystem carbon, climate and biosphere exchange, and land use management. A combination of LST and the EVI indices in the global disturbance index (DI) has been proven to be useful for detecting and monitoring of changes in land covers at continental scales. However, this model has not been adequately applied or assessed in tropical regions. We aimed to demonstrate and evaluate the DI algorithm used to detect spatial change in land covers in Lao tropical forests. We used the land surface temperature and enhanced vegetation index of the Moderate Resolution Imaging Spectroradiometer time-series products from 2006-2012. We used two dates Google EarthTM images in 2006 and 2012 as ground truth data for accuracy assessment of the model. This research demonstrated that the DI was capable of detecting vegetation changes during seven-year periods with high overall accuracy;however, it showed low accuracy in detecting vegetation decrease. 展开更多
关键词 Tropical VEGETATION change DISTURBANCE index Land Surface Temperature (LST) Enhanced VEGETATION index (EVI) Lao PDR
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Response of vegetation variation to climate change and human activities in the Shiyang River Basin of China during 2001-2022
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作者 SUN Chao BAI Xuelian +2 位作者 WANG Xinping ZHAO Wenzhi WEI Lemin 《Journal of Arid Land》 SCIE CSCD 2024年第8期1044-1061,共18页
Understanding the response of vegetation variation to climate change and human activities is critical for addressing future conflicts between humans and the environment,and maintaining ecosystem stability.Here,we aime... Understanding the response of vegetation variation to climate change and human activities is critical for addressing future conflicts between humans and the environment,and maintaining ecosystem stability.Here,we aimed to identify the determining factors of vegetation variation and explore the sensitivity of vegetation to temperature(SVT)and the sensitivity of vegetation to precipitation(SVP)in the Shiyang River Basin(SYRB)of China during 2001-2022.The climate data from climatic research unit(CRU),vegetation index data from Moderate Resolution Imaging Spectroradiometer(MODIS),and land use data from Landsat images were used to analyze the spatial-temporal changes in vegetation indices,climate,and land use in the SYRB and its sub-basins(i.e.,upstream,midstream,and downstream basins)during 2001-2022.Linear regression analysis and correlation analysis were used to explore the SVT and SVP,revealing the driving factors of vegetation variation.Significant increasing trends(P<0.05)were detected for the enhanced vegetation index(EVI)and normalized difference vegetation index(NDVI)in the SYRB during 2001-2022,with most regions(84%)experiencing significant variation in vegetation,and land use change was determined as the dominant factor of vegetation variation.Non-significant decreasing trends were detected in the SVT and SVP of the SYRB during 2001-2022.There were spatial differences in vegetation variation,SVT,and SVP.Although NDVI and EVI exhibited increasing trends in the upstream,midstream,and downstream basins,the change slope in the downstream basin was lower than those in the upstream and midstream basins,the SVT in the upstream basin was higher than those in the midstream and downstream basins,and the SVP in the downstream basin was lower than those in the upstream and midstream basins.Temperature and precipitation changes controlled vegetation variation in the upstream and midstream basins while human activities(land use change)dominated vegetation variation in the downstream basin.We concluded that there is a spatial heterogeneity in the response of vegetation variation to climate change and human activities across different sub-basins of the SYRB.These findings can enhance our understanding of the relationship among vegetation variation,climate change,and human activities,and provide a reference for addressing future conflicts between humans and the environment in the arid inland river basins. 展开更多
关键词 vegetation variation climate change land use change normalized difference vegetation index(NDVI) enhanced vegetation index(EVI) Shiyang River Basin
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Effects of nitrogen deposition on the carbon budget and water stress in Central Asia under climate change
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作者 HAN Qifei XU Wei LI Chaofan 《Journal of Arid Land》 SCIE CSCD 2024年第8期1118-1129,共12页
Atmospheric deposition of nitrogen(N)plays a significant role in shaping the structure and functioning of various terrestrial ecosystems worldwide.However,the magnitude of N deposition on grassland ecosystems in Centr... Atmospheric deposition of nitrogen(N)plays a significant role in shaping the structure and functioning of various terrestrial ecosystems worldwide.However,the magnitude of N deposition on grassland ecosystems in Central Asia still remains highly uncertain.In this study,a multi-data approach was adopted to analyze the distribution and amplitude of N deposition effects in Central Asia from 1979 to 2014 using a process-based denitrification decomposition(DNDC)model.Results showed that total vegetation carbon(C)in Central Asia was 0.35(±0.09)Pg C/a and the averaged water stress index(WSI)was 0.20(±0.02)for the whole area.Increasing N deposition led to an increase in the vegetation C of 65.56(±83.03)Tg C and slightly decreased water stress in Central Asia.Findings of this study will expand both our understanding and predictive capacity of C characteristics under future increases in N deposition,and also serve as a valuable reference for decision-making regarding water resources management and climate change mitigation in arid and semi-arid areas globally. 展开更多
关键词 carbon dynamics climate change grassland ecosystems nitrogen deposition water stress index
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Coupled effects of climate change and human activities on vegetation dynamics in the Southwestern Alpine Canyon Region of China
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作者 LAI Jinlin QI Shi 《Journal of Mountain Science》 SCIE CSCD 2024年第10期3234-3248,共15页
The driving effects of climate change and human activities on vegetation change have always been a focal point of research.However,the coupling mechanisms of these driving factors across different temporal and spatial... The driving effects of climate change and human activities on vegetation change have always been a focal point of research.However,the coupling mechanisms of these driving factors across different temporal and spatial scales remain controversial.The Southwestern Alpine Canyon Region of China(SACR),as an ecologically fragile area,is highly sensitive to the impacts of climate change and human activities.This study constructed a vegetation cover dataset for the SACR based on the Enhanced Vegetation Index(EVI)from 2000 to 2020.Spatial autocorrelation,Theil-Sen trend,and Mann-Kendall tests were used to analyze the spatiotemporal characteristics of vegetation cover changes.The main drivers of spatial heterogeneity in vegetation cover were identified using the optimal parameter geographic detector,and an improved residual analysis model was employed to quantify the relative contributions of climate change and human activities to interannual vegetation cover changes.The main findings are as follows:Spatially,vegetation cover exceeds 60%in most areas,especially in the southern part of the study area.However,the border area between Linzhi and Changdu exhibits lower vegetation cover.Climate factors are the primary drivers of spatial heterogeneity in vegetation cover,with temperature having the most significant influence,as indicated by its q-value,which far exceeds that of other factors.Additionally,the interaction q-value between the two factors significantly increases,showing a relationship of bivariate enhancement and nonlinear enhancement.In terms of temporal changes,vegetation cover shows an overall improving trend from 2000 to 2020,with significant increases observed in 68.93%of the study area.Among these,human activities are the main factors driving vegetation cover change,with a relative contribution rate of 41.31%,while climate change and residual factors contribute 35.66%and 23.53%,respectively.By thoroughly exploring the coupled mechanisms of vegetation change,this study provides important references for the sustainable management and conservation of the vegetation ecosystem in the SACR. 展开更多
关键词 Enhanced vegetation index Climate change Human activities Spatial heterogeneity Coupled mechanisms
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Impacts of climate change and human activities on vegetation dynamics on the Mongolian Plateau, East Asia from 2000 to 2023
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作者 YAN Yujie CHENG Yiben +3 位作者 XIN Zhiming ZHOU Junyu ZHOU Mengyao WANG Xiaoyu 《Journal of Arid Land》 SCIE CSCD 2024年第8期1062-1079,共18页
The Mongolian Plateau in East Asia is one of the largest contingent arid and semi-arid areas of the world.Under the impacts of climate change and human activities,desertification is becoming increasingly severe on the... The Mongolian Plateau in East Asia is one of the largest contingent arid and semi-arid areas of the world.Under the impacts of climate change and human activities,desertification is becoming increasingly severe on the Mongolian Plateau.Understanding the vegetation dynamics in this region can better characterize its ecological changes.In this study,based on Moderate Resolution Imaging Spectroradiometer(MODIS)images,we calculated the kernel normalized difference vegetation index(kNDVI)on the Mongolian Plateau from 2000 to 2023,and analyzed the changes in kNDVI using the Theil-Sen median trend analysis and Mann-Kendall significance test.We further investigated the impact of climate change on kNDVI change using partial correlation analysis and composite correlation analysis,and quantified the effects of climate change and human activities on kNDVI change by residual analysis.The results showed that kNDVI on the Mongolian Plateau was increasing overall,and the vegetation recovery area in the southern region was significantly larger than that in the northern region.About 50.99%of the plateau showed dominant climate-driven effects of temperature,precipitation,and wind speed on kNDVI change.Residual analysis showed that climate change and human activities together contributed to 94.79%of the areas with vegetation improvement.Appropriate human activities promoted the recovery of local vegetation,and climate change inhibited vegetation growth in the northern part of the Mongolian Plateau.This study provides scientific data for understanding the regional ecological environment status and future changes and developing effective ecological protection measures on the Mongolian Plateau. 展开更多
关键词 kernel normalized difference vegetation index(kNDVI) human activities climate change partial correlation analysis composite correlation analysis residual analysis Mongolian Plateau
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Comparison of resistive index and shear-wave elastography in the evaluation of chronic kidney allograft dysfunction
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作者 Ameet Kumar Jesrani Syed M Faiq +5 位作者 Rahma Rashid Tariq Ali Kalwar Rehan Mohsin Tahir Aziz Nida Amin Khan Muhammed Mubarak 《World Journal of Transplantation》 2024年第1期154-163,共10页
BACKGROUND Detection of early chronic changes in the kidney allograft is important for timely intervention and long-term survival.Conventional and novel ultrasound-based investigations are being increasingly used for ... BACKGROUND Detection of early chronic changes in the kidney allograft is important for timely intervention and long-term survival.Conventional and novel ultrasound-based investigations are being increasingly used for this purpose with variable results.AIM To compare the diagnostic performance of resistive index(RI)and shear wave elastography(SWE)in the diagnosis of chronic fibrosing changes of kidney allograft with histopathological results.METHODS This is a cross-sectional and comparative study.A total of 154 kidney transplant recipients were included in this study,which was conducted at the Departments of Transplantation and Radiology,Sindh Institute of Urology and Transplantation,Karachi,Pakistan,from August 2022 to February 2023.All consecutive patients with increased serum creatinine levels and reduced glomerular filtration rate(GFR)after three months of transplantation were enrolled in this study.SWE and RI were performed and the findings of these were evaluated against the kidney allograft biopsy results to determine their diagnostic utility.RESULTS The mean age of all patients was 35.32±11.08 years.Among these,126(81.8%)were males and 28(18.2%)were females.The mean serum creatinine in all patients was 2.86±1.68 mg/dL and the mean estimated GFR was 35.38±17.27 mL/min/1.73 m2.Kidney allograft biopsy results showed chronic changes in 55(37.66%)biopsies.The sensitivity,specificity,positive predictive value(PPV),and negative predictive value(NPV)of SWE for the detection of chronic allograft damage were 93.10%,96.87%%,94.73%,and 95.87%,respectively,and the diagnostic accuracy was 95.45%.For RI,the sensitivity,specificity,PPV,and NPV were 76.92%,83.33%,70.17%,and 87.62%,respectively,and the diagnostic accuracy was 81.16%.CONCLUSION The results from this study show that SWE is more sensitive and specific as compared to RI in the evaluation of chronic allograft damage.It can be of great help during the routine follow-up of kidney transplant recipients for screening and early detection of chronic changes and selecting patients for allograft biopsy. 展开更多
关键词 Shear wave SONOELASTOGRAPHY Resistive index Chronic allograft changes Biopsy HISTOPATHOLOGY
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A CMIP6-based assessment of regional climate change in the Chinese Tianshan Mountains
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作者 LIU Xinyu LI Xuemei +2 位作者 ZHANG Zhengrong ZHAO Kaixin LI Lanhai 《Journal of Arid Land》 SCIE CSCD 2024年第2期195-219,共25页
Climate warming profoundly affects hydrological changes,agricultural production,and human society.Arid and semi-arid areas of China are currently displaying a marked trend of warming and wetting.The Chinese Tianshan M... Climate warming profoundly affects hydrological changes,agricultural production,and human society.Arid and semi-arid areas of China are currently displaying a marked trend of warming and wetting.The Chinese Tianshan Mountains(CTM)have a high climate sensitivity,rendering the region particularly vulnerable to the effects of climate warming.In this study,we used monthly average temperature and monthly precipitation data from the CN05.1 gridded dataset(1961-2014)and 24 global climate models(GCMs)of the Coupled Model Intercomparison Project Phase 6(CMIP6)to assess the applicability of the CMIP6 GCMs in the CTM at the regional scale.Based on this,we conducted a systematic review of the interannual trends,dry-wet transitions(based on the standardized precipitation index(SPI)),and spatial distribution patterns of climate change in the CTM during 1961-2014.We further projected future temperature and precipitation changes over three terms(near-term(2021-2040),mid-term(2041-2060),and long-term(2081-2100))relative to the historical period(1961-2014)under four shared socio-economic pathway(SSP)scenarios(i.e.,SSP1-2.6,SSP2-4.5,SSP3-7.0,and SSP5-8.5).It was found that the CTM had experienced significant warming and wetting from 1961 to 2014,and will also experience warming in the future(2021-2100).Substantial warming in 1997 was captured by both the CN05.1 derived from interpolating meteorological station data and the multi-model ensemble(MME)from the CMIP6 GCMs.The MME simulation results indicated an apparent wetting in 2008,which occurred later than the wetting observed from the CN05.1 in 1989.The GCMs generally underestimated spring temperature and overestimated both winter temperature and spring precipitation in the CTM.Warming and wetting are more rapid in the northern part of the CTM.By the end of the 21st century,all the four SSP scenarios project warmer and wetter conditions in the CTM with multiple dry-wet transitions.However,the rise in precipitation fails to counterbalance the drought induced by escalating temperature in the future,so the nature of the drought in the CTM will not change at all.Additionally,the projected summer precipitation shows negative correlation with the radiative forcing.This study holds practical implications for the awareness of climate change and subsequent research in the CTM. 展开更多
关键词 climate change Coupled Model Intercomparison Project Phase 6(CMIP6) global climate models(GCMs) shared socio-economic pathway(SSP)scenarios standardized precipitation index(SPI) Chinese Tianshan Mountains
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Effect of Si δ-Doping on the Linear and Nonlinear Optical Absorptions and Refractive Index Changes in InAlN/GaN Single Quantum Wells
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作者 Shaffa Almansour Hassen Dakhlaoui Emane Algrafy 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第2期102-105,共4页
In the framework of effective mass approximation, we theoretically investigate the electronic structure of the Si δ-doped InAIN/GaN single quantum well by solving numerically the coupled equations Schrodinger-Poisson... In the framework of effective mass approximation, we theoretically investigate the electronic structure of the Si δ-doped InAIN/GaN single quantum well by solving numerically the coupled equations Schrodinger-Poisson self-consistently. The linear, nonlinear optical absorption coefficients and relative refractive index changes are calculated as functions of the doping concentration and its thickness. The obtained results show that the position and the amplitude of the linear and total optical absorption coefficients and the refractive index changes can be modified by varying the doping concentration and its thickness. In addition, it is found that the maximum of the optical absorption can be red-shifted or blue-shifted by varying the doping concentration. The obtained results are important for the design of various electronic components such as high-power FETs and infrared photonic devices. 展开更多
关键词 of is In GAN in Doping on the Linear and Nonlinear Optical Absorptions and Refractive index changes in InAlN/GaN Single Quantum Wells on
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Study on Ecological Change Remote Sensing Monitoring Method Based on Elman Dynamic Recurrent Neural Network
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作者 Zhen Chen Yiyang Zheng 《Journal of Geoscience and Environment Protection》 2024年第4期31-44,共14页
In this paper, Hailin City of Heilongjiang Province, China is taken as the research area. As an important city in Heilongjiang Province, China, the sustainable development of its ecological environment is related to t... In this paper, Hailin City of Heilongjiang Province, China is taken as the research area. As an important city in Heilongjiang Province, China, the sustainable development of its ecological environment is related to the opening up, economic prosperity and social stability of Northeast China. In this paper, the remote sensing ecological index (RSEI) of Hailin City in recent 20 years was calculated by using Landsat 5/8/9 series satellite images, and the temporal and spatial changes of the ecological environment in Hailin City were further analyzed and the influencing factors were discussed. From 2003 to 2023, the mean value of RSEI in Hailin City decreased and increased, and the ecological environment decreased slightly as a whole. RSEI declined most significantly from 2003 to 2008, and it increased from 2008 to 2013, decreased from 2013 to 2018, and increased from 2018 to 2023 again, with higher RSEI value in the south and lower RSEI value in the northwest. It is suggested to appropriately increase vegetation coverage in the northwest to improve ecological quality. As a result, the predicted value of Elman dynamic recurrent neural network model is consistent with the change trend of the mean value, and the prediction error converges quickly, which can accurately predict the ecological environment quality in the future study area. 展开更多
关键词 Remote Sensing Ecological index Long Time Series Space-Time change Elman Dynamic Recurrent Neural Network
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Changes of biochemical indexes in patients with acute cerebral infarction after treatment with simvastatin
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作者 Cheng Yang 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第9期856-858,共3页
BACKGROUND: At present, it is believed that the important causes of cerebral infarction are the disorders of lipid metabolism and endothelial function, and the outcomes of clinical treatment can be improved by regulat... BACKGROUND: At present, it is believed that the important causes of cerebral infarction are the disorders of lipid metabolism and endothelial function, and the outcomes of clinical treatment can be improved by regulating serum lipids and antiinflammation, etc. OBJECTIVE: To observe the effect of simvastatin, inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, on the levels of serum lipids, serum enzymic indexes and inflammatory metabolic indexes in patients with cerebral infarction. DESIGN: A comparative observation. SETTING: Department of Geriatrics, Longquanshan Hospital of Liuzhou City. PARTICIPANTS: Forty-eight patients with acute cerebral infarction were selected from the Department of Geriatrics of Longquanshan Hospital of Liuzhou from March 2004 to February 2006, including 24 males and 24 females, the mean age was (54±12) years, average disease course was (10.0±4.5) days. They were all accorded with the diagnostic standard for cerebral infarction set by the Fourth National Academic Meeting for Cerebrovascular Disease in 1999, and cerebral hemorrhage was excluded by cranial CT scanning. The 48 patients were randomly divided into control group (n =24) and treatment group (n =24). Informed consents were obtained from all the participants. METHODS: ① All the patients were treated according to the symptoms, besides those in the treatment group were given simvastatin (Harbin Pharm. Group Sanjing Pharmaceutical Shareholding, Co.,Ltd., No. H20010454; Batch number: 20040218; 5 mg/tablet). The initial dosage was 10 mg per day for 4 weeks, and then increased to 30 mg per day for another 4 weeks. ② Before treatment and within 1 week after treatment, the total cholesterol, triglyceride, high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), aspartate aminotransferase (AST), creatine kinase and C reactive protein in serum were determined with Beckman-cx7 automatic biochemical analytical apparatus in both groups. ③ The differences of intergroup and intragroup data were compared with the independent-samples t test and paired samples t test. MAIN OUTCOME MEASURES: Changes of total cholesterol, triglyceride, HDL-C, LDL-C, AST, creatine kinase and C reactive protein before and treatment in both groups. RESULTS: All the 48 patients with cerebral infarction were involved in the analysis of results. ① Changes of serum lipids: The levels of serum lipids were close between the two groups before treatment (P > 0.05). After treatment, the HDL-C level in the treatment group was obviously higher than that in the control group and that before treatment [(1.34±0.12), (0.92±0.33), (0.93±0.21) mmol/L, t =7.922, 11.699, P < 0.01], and the levels of total cholesterol, triglyceride and LDL-C were obviously lower than those in the control group and those before treatment (t =2.780-7.591, P < 0.01). ② Changes of serum enzymic indexes and C reactive protein in serum: The levels of enzymes and C reactive protein in serum had no obvious differences between the two groups before treatment (P > 0.05). The levels of AST, creatine kinase and C reactive protein in serum after treatment were obviously lower than those before treatment in both groups (t =7.259-17.996, P < 0.01). The levels of levels of creatine kinase and C reactive protein in serum after treatment in the treatment group were obviously lower than those in the control group [(3.061±0.522) μkat/L, (4.6±3.1) mg/L; (4.348±0.580) μkat/L, (12.3±4.8) mg/L, t =7.910, 6.463, P < 0.01]. CONCLUSION: Compared with common treatment according to symptoms, the additional administration of simvastatin is better for improving the serum lipids, serum enzymic indexes of patients with cerebral infarction at acute period, and benefit for repairing their inflammatory damages. 展开更多
关键词 changes of biochemical indexes in patients with acute cerebral infarction after treatment with simvastatin
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Existence of Monotone Positive Solution for a Fourth-Order Three-Point BVP with Sign-Changing Green’s Function
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作者 Junrui Yue Yun Zhang Qingyue Bai 《Open Journal of Applied Sciences》 2024年第1期63-69,共7页
This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones a... This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones and iterative technique. 展开更多
关键词 Fourth-Order Three-Point Boundary Value Problem Sign-changing Green’s Function Fixed Point index Iterative Technique Monotone Positive Solution EXISTENCE
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Seasonal Dynamics of Terrestrial Net Primary Production in Response to Climate Changes in China 被引量:32
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作者 朴世龙 方精云 陈安平 《Acta Botanica Sinica》 CSCD 2003年第3期269-275,共7页
Study on seasonal responses of terrestrial net primary production (NPP) to climate changes is to help understand feedback between climate systems and terrestrial ecosystems and mechanisms of increased NPP in the north... Study on seasonal responses of terrestrial net primary production (NPP) to climate changes is to help understand feedback between climate systems and terrestrial ecosystems and mechanisms of increased NPP in the northern middle and high latitudes. In this study, time series dataset of normalized difference vegetation index (NDVI) and corresponding ground-based information on vegetation, climate, soil, and solar radiation, together with an ecological process model, were used to explore the seasonal trends of terrestrial NPP and their geographical differences in China from 1982 to 1999. As the results,. seasonal total NPP in China showed a significant increase for all four seasons (spring, summer, autumn and winter) during the past 18 years. The spring NPP indicated the largest increase rate, while the summer NPP was with the largest increase in magnitude. The response of NPP to climate changes varied with different vegetation types. The increased NPP was primarily led by an advanced growing season for broadleaf evergreen forest, needle-leaf evergreen forest, and needle-leaf deciduous forest, whilst that was mainly due to enhanced vegetation activity (amplitude of growth cycle) during growing season for broadleaf deciduous forest, broadleaf and needle-leaf mixed forest, broadleaf trees with groundcover, perennial grasslands, broadleaf shrubs with grasslands, tundra, desert, and cultivation. The regions with the largest increase in spring NPP appeared mainly in eastern China, while the areas with the largest increase in summer NPP occurred in most parts of Northwestern China, Qinghai-Xizang Plateau, Mts. Xiaoxinganling-Changbaishan, Sanjiang Plain, Songliao Plain, Sichuan Basin, Leizhou Peninsula, part of the middle and lower Yangtze River, and southeastern mountainous areas of China. In autumn, the largest NPP increase appeared in Yunnan Plateau-Eastern Xizang and the areas around Hulun Lake. Such different ways of the NPP responses depended on regional climate attributes and their changes. 展开更多
关键词 Carnegie-Ames-Stanford-Approach (CASA) model net primary production (NPP) seasonal change normalized difference vegetation index (NDVI) climate change
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