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Assessment of wetland fragmentation in the middle reaches of the Heihe River by the type change tracker model 被引量:6
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作者 RuiFeng ZHAO ZuoLun XIE +3 位作者 LiHua ZHANG Wen ZHU Jie LI Dan LIANG 《Journal of Arid Land》 SCIE CSCD 2015年第2期177-188,共12页
The quantitative research of wetland landscape fragmentation in the middle reaches of the Heihe River is important for the wetland and oasis sustainable development in the Hexi Corridor. Based on the data of remote se... The quantitative research of wetland landscape fragmentation in the middle reaches of the Heihe River is important for the wetland and oasis sustainable development in the Hexi Corridor. Based on the data of remote sensing and GIS, we constructed the type change tracker model with sliding window technique and spatially mor- phological rule. The suitable scale and optimum scale of the fragmentation model of wetland landscape in the middle reaches of the Heihe River were determined by the area frequency statistics method, Chi-square distribution normal- ized scale variance, fractal dimension and diversity index. By integrating type change tracker model and the optimum scale with GIS spatial analysis, the spatial distribution characteristics of wetland landscape fragmentation in different periods and the related spatial-temporal change process were clarified. The results showed that (1) the type change tracker model, which analyzes the spatial pattern of wetland fragmentation on the pixel level, is better than the tradi- tional wetland fragmentation analysis on the landscape and patch levels; (2) The suitable scale for the wetland frag- mentation ranged from 150 rex150 m to 450 mx450 m and the optimum scale was 250 mx250 m in the middle reaches of the Heihe River; and (3) In the past 35 years, the total wetland area decreased by 23.2% and the frag- mentatJon of wetland markedly increased in the middle reaches of the Heihe River. The areas of core wetlands re- duced by 12.8% and the areas of perforated, edge and patch wetlands increased by 0.8%, 3.1% and 8.9%, respec- tively. The process of wetland fragmentation in the research region showed the order of core wetland, perforated or edge wetland, patch wetland or non-wetland. The results of this study would provide a reference for the protection, utilization and restoration of limited wetland resources and for the sustainable development of the regional eco-environment in the Heihe River Basin. 展开更多
关键词 WETLAND landscape pattern fragmentation the type change tracker model Heihe River
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Using REE Tracers to Measure Sheet Erosion Changing to Rill Erosion
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作者 宋炜 刘普灵 +1 位作者 杨明义 薛亚洲 《Journal of Rare Earths》 SCIE EI CAS CSCD 2003年第5期587-590,共4页
Rare earth element(REE) tracer method was used to study sheet erosion changing to rill erosion on slope land. By placing different REE on different soil depth across a slope in an indoor plot, two simulated rainfalls ... Rare earth element(REE) tracer method was used to study sheet erosion changing to rill erosion on slope land. By placing different REE on different soil depth across a slope in an indoor plot, two simulated rainfalls were applied to study the change of erosion type and the rill erosion process. The results indicate that the main erosion type is sheet erosion at the beginning of the rainfalls, and serious erosion happens after rill erosion appears. Accumulated sheet and rill erosion amount increases with the rainfalls time. The percentage of sheet erosion amount decreases and rill erosion percentage increases with time. At the end of the rainfalls, the total rill erosion amounts are 4.3 and 5 times more than sheet erosion. In this paper, a new REE tracer method was used to quantitatively distinguish sheet and rill erosion amount. The new REE tracer method should be useful to future studying of erosion processes on slope lands. 展开更多
关键词 GEOCHEMISTRY soil erosion erosion type change REE tracer method slope land rare earths
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Detergent-Induced Changes in the Protein Constituents of Various Cell Types of Opercular Epidermis of Rita rita
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作者 DEBASISH ROY 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1990年第3期290-298,共9页
Fish (Rita rita) were exposed to an anionic detergent, dodecylbenzene sodium sulfonate, at a concentration of 6.9mg/liter (96-hr LC_(50) of the detergent).A series of histochemical techniques, used in this study for t... Fish (Rita rita) were exposed to an anionic detergent, dodecylbenzene sodium sulfonate, at a concentration of 6.9mg/liter (96-hr LC_(50) of the detergent).A series of histochemical techniques, used in this study for the demonstration of various protein constituents, indicated a gradual decrease in the intensity of staining reactions of the cytoplasmic material, suggesting a loss of protein moieties from the club cells and the epithelial cells of the opercular epidermis as a result of detergent exposure. 1990 Academic Press.Inc. 展开更多
关键词 In Detergent-Induced Changes in the Protein Constituents of Various Cell types of Opercular Epidermis of Rita rita
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Assessment of Urban Morphology through Local Climate Zone Clas­sification and Detection of the Changing Building States of Siliguri Municipal Corporation and Its Surrounding Area, West Bengal
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作者 Ivana Hoque Sushma Rohatgi 《Journal of Geographical Research》 2022年第2期28-43,共16页
Progressive population concentration to the urban centres has fuelled urban expansion in both horizontal as well as vertical direction,consequences in the urban landscape change.This growth resulted in posing many com... Progressive population concentration to the urban centres has fuelled urban expansion in both horizontal as well as vertical direction,consequences in the urban landscape change.This growth resulted in posing many complexities towards sustainable urban development which can be counted by observing the changing proportions of natural landscapes and built up areas.Local climate zones(LCZs),a systematic classification of natural lands and built up lands,are identified in Siliguri Municipal Corporation(SMC)and its surrounding region to explore the spatio temporal complexity of urban growth in recent years.Rapid urbanization and population growth of SMC have led to change the building states from low rise to mid and high rise which added an important feature to the urban landscape dynamics of the area.The work intends to provide the vision of spatial urban morphology of the area through investigation of its changing land use and changing urban built space using the LCZ classification.The study shows that the WUDAPT method can accurately generate LCZs,especially the built type LCZs.The results of the proposed LCZ classification scheme are tested using error matrix for the year 2001 and 2021 having coefficient values of 0.79 and 0.81 respectively.The study explores the changing pattern of building states of SMC using LCZ products,which is essential for proper urban planning implementations. 展开更多
关键词 LCZ classification Urban land cover SMC changing urban building types
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Globalization Under the Spells of Breakdowns in Supply Chains, Regime Change, Regime Formation, and Alliance Restructuring: How Much Is Left for Public Goods?
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作者 Ekkart Zimmermann 《International Relations and Diplomacy》 2023年第5期211-216,共6页
In a paper conceived about five years ago(“Globalization and Public Goods:Too Big to Tackle?”)roughly a dozen factors were linked to explain important causal paths from globalization to the potential output of publi... In a paper conceived about five years ago(“Globalization and Public Goods:Too Big to Tackle?”)roughly a dozen factors were linked to explain important causal paths from globalization to the potential output of public goods.The Russian invasion of Ukraine,the corona epidemic,and the increased hegemonic rivalry between China and the U.S.interrupted or even destroyed many of the linkages between globalization and potential public good production.About five important detrimental paths involved in the meantime.In the present article we aim at linking what is left from the previous level of globalization or emerging to form a new and simplified causal model for likely linkages between truncated or(re-)emerging globalization,and the deadly needed output of public goods.These linkages refer to rules of climate control,go to trade linkages and arbitrary tariffs and trade interventions.Regime change,regime formation,and alliance restructuring address aspects of domestic rule and international stability.Selectorate theory,regime type,and exit options for political elites provide key explanatory factors in explaining globalization and public goods productions,or their decay.Where possible we use some data and transformation experiences corroborating our arguments.In other instances need for further empirical macro research will become clear. 展开更多
关键词 hegemonic rivalry new alliances and bloc formation de-globalization and re-globalization selectorate theory regime type and regime change elite exit options public goods
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Using modified Soil Conservation Service curve number method to simulate the role of forest in flood control in the upper reach of the Tingjiang River in China 被引量:3
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作者 LIN Wei YANG Fan +2 位作者 ZHOU Liang XU Jian-gang ZHANG Xing-qi 《Journal of Mountain Science》 SCIE CSCD 2017年第1期1-14,共14页
To improve flood control efficiency and increase urban resilience to flooding,the impacts of forest type change on flood control in the upper reach of the Tingjiang River(URTR) were evaluated by a modified model based... To improve flood control efficiency and increase urban resilience to flooding,the impacts of forest type change on flood control in the upper reach of the Tingjiang River(URTR) were evaluated by a modified model based on the Soil Conservation Service curve number(SCS-CN) method. Parameters of the model were selected and determined according to the comprehensive analysis of model evaluation indexes. The first simulation of forest reconstruction scenario,namely a coniferous forest covering 59.35km^2 is replaced by a broad-leaved forest showed no significant impact on the flood reduction in the URTR. The second simulation was added with 61.75km^2 bamboo forest replaced by broad-leaved forest,the reduction of flood peak discharge and flood volume could be improved significantly. Specifically,flood peak discharge of 10-year return period event was reduced to 7-year event,and the reduction rate of small flood was 21%-28%. Moreover,the flood volume was reduced by 9%-14% and 18%-35% for moderate floods and small floods,respectively. The resultssuggest that the bamboo forest reconstruction is an effective control solution for small to moderate flood in the URTR,the effect of forest conversion on flood volume is increasingly reduced as the rainfall amount increases to more extreme magnitude. Using a hydrological model with scenarios analysis is an effective simulation approach in investigating the relationship between forest type change and flood control. This method would provide reliable support for flood control and disaster mitigation in mountainous cities. 展开更多
关键词 Flood control Soil Conservation Service curve number method Forest type change Scenarios simulation Tingjiang River
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Effects of the Land Use Change on Ecosystem Service Value Based on RS & GIS 被引量:1
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作者 PENG Wenfu WANG Guangjie +1 位作者 ZHOU Jieming XU Xinliang 《Journal of Landscape Research》 2015年第1期21-26,共6页
Assessing the effect of land use change on ecosystem service value(ESV) can provide reference for sustainable land use and ecological environment protection. The land use information was extracted and analyzed based o... Assessing the effect of land use change on ecosystem service value(ESV) can provide reference for sustainable land use and ecological environment protection. The land use information was extracted and analyzed based on Landsat TM images in Shuangliu County, Sichuan Province from 1992 to 2008, following remote sensing(RS) and GIS. The ESV of the land use change in study area was evaluated by adopting the service value method within Chinese terrestrial ecosystem. The results showed that:(1) the area of paddy field and forest land reduced in the 16 years, total area of construction land expanded fast on the basis of occupying paddy field and forest land.(2) The regional ESV increased by 4,508.859×104 RMB, but there is different change trend at different times, such as the ESV fell by 10.59% in 1992–2000, increased by 16.024% in 2000–2008.(3) The conversion from forest land and cultivated land to construction land caused a decline and negative flow in ESV, the total value was 2,197.233×104 RMB and 5,317.460×104 RMB.(4) All land use types showed that change of the ESV coefficient was less elastic, the relative sensitivity: forest land > cultivated land > water area. In terms of variability of ESV, water area change had greater influence on the change of ESV in the study area, and cultivated land and forest land had relatively smaller impact. 展开更多
关键词 Land use type change Ecosystem service value(ESV) Shuangliu County Remote sensing(RS) GIS
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An Efficient Approach for Historical Storage and Retrieval of Segmented Road Data in Geographic Information System for Transportation
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作者 Mohammad Reza Jelokhani-Niaraki Ali Asghar Alesheikh Abolghasem Sadeghi-Niaraki 《Chinese Geographical Science》 SCIE CSCD 2010年第3期236-242,共7页
One of the most powerful functions of Geographic Information System for Transportation (GIS-T) is Dynamic Segmentation (DS), which is used to increase the efficiency and precision of road management by generating segm... One of the most powerful functions of Geographic Information System for Transportation (GIS-T) is Dynamic Segmentation (DS), which is used to increase the efficiency and precision of road management by generating segments based on attributes. The road segments describing transportation data are both spatially and temporally referenced. For a variety of transportation applications, historical road segments must be preserved. This study presents an appropriate approach to preserve and retrieve the historical road segments efficiently. In the proposed method, only the portions of segments of a time stamp that have been changed into new segments rather than storing the entire segments for every old time stamp are recorded .The storage of these portions is based on the type of changes. A recursive algorithm is developed to retrieve all segments for every old time stamp. Experimental results using real data of Tehran City, Iran justify the strength of the proposed approach in many aspects. An important achievement of the results is that database volume for 2006, 2007 and 2008 within the Historical Line Event Table (HLET) is reduced by 70%, 80% and 78%, respectively. The proposed method has the potential to prevent from vast data redundancy and the unnecessary storage of entire segments for each time stamp. Since the present technique is performed on ordinary plain tables that are readable by all GIS software, special software platforms to manage the storage and retrieval of historical segments are not needed. In addition, this method simplifies spatio-temporal queries. 展开更多
关键词 GIS-T dynamic segmentation change type recursive algorithm time stamp
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Intraosseous Radiofrequency Ablation of the Basivertebral Nerve in Chronic Low Back Pain: A Meta-Analysis
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作者 Alistair J. Loan David C. Kieser 《Open Journal of Radiology》 2021年第3期81-90,共10页
<strong>Purpose:</strong> To review the literature on the value of basivertebral nerve abla-tion in the treatment of chronic low back pain. <strong>Materials and Method:</strong> A systematic r... <strong>Purpose:</strong> To review the literature on the value of basivertebral nerve abla-tion in the treatment of chronic low back pain. <strong>Materials and Method:</strong> A systematic review and meta-analysis of the English literature to March 2020 was undertaken. The inclusion criteria were patients with discogenic back pain of more than 3 months duration with modic type 1 or 2 change and suc-cessful disc block or discogram. Primary outcomes were VAS pain, ODI, EQ-5D and SF36 improvement. Secondary outcomes were complications. <strong>Results:</strong> 6 studies were included, all funded by the same company, but oth-erwise of low bias. All studies showed significant improvement in all scores over the first 3 months with evidence these would be maintained over the longer term. There was one reported compression fracture, but otherwise no significant adverse events. <strong>Conclusion:</strong> This study supports the conclusion that radiofrequency ablation of the basivertebral nerve is a safe and effective treatment for discogenic chronic low back pain. 展开更多
关键词 Basivertebral Nerve Radiofrequency Ablation Chronic Back Pain Discogenic Back Pain Modic type Changes
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Globalization and Public Goods:Too Big to Tackle?
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作者 Ekkart Zimmermann 《International Relations and Diplomacy》 2022年第4期190-195,共6页
The massive Russian invasion of Ukraine in 2022 will have unforeseeable effects on the themes addressed here,from international regime change to infra-structural re-orientation to value changes.Here we concentrate on ... The massive Russian invasion of Ukraine in 2022 will have unforeseeable effects on the themes addressed here,from international regime change to infra-structural re-orientation to value changes.Here we concentrate on the positive cycle of effects globalization has brought about before the new war in Europe,mainly economic growth and(some)pressures for democratic development,as well as the negative cycle that originates in(relative)economic decline,elite dissent,even failed states and regime change,often in the direction of counter-democracy.The causal links between 13 independent and intervening variables and public goods as the dependent variable are specified in this explanatory sketch.There is need for broadening the view in explaining causal paths between globalization factors and the production of public goods.In doing that we focus in particular on variables like elite dissent,immigration,and new minorities,all three weakening the capacities of states to respond.Further we state that all four:ecological challenges,economic and social inequality and polarization,regime change,and international terrorism can be viewed as to their joint effects on the production of public goods.Selectorate theory is crucial.It explains political regimes on the base of the size of the selectorate with large(s)electorates producing public goods,as in democracies,and small ones only private ones,as in sultanist regimes and dictatorships. 展开更多
关键词 GLOBALIZATION regime types and changes selectorate theory public goods
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Demon Genes May Deform Common Syndromes: Collagen VI Gene Change in Down Syndrome Unifies the Medical and Molecular Approach to Hypermobility Disorders
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作者 Golder N. Wilson Vijay S. Tonk 《Journal of Biosciences and Medicines》 2022年第3期1-7,共7页
Purpose: To alert the medical community that whole exome sequencing can find accessory gene changes in well-known syndromes that alter preventive health care and management. Meaning: A collagen type VI gene change add... Purpose: To alert the medical community that whole exome sequencing can find accessory gene changes in well-known syndromes that alter preventive health care and management. Meaning: A collagen type VI gene change adds muscle weakness, hypermobility, and dysautonomia concerns to usual management considerations for Down syndrome. Methods: Commercial whole exome sequencing combined with clinical interpretation of DNA sequence change added new considerations to patient management and parental counsel. Results: An 11-year-old child with the trisomy 21 form of Down syndrome who was evaluated for extraordinary joint laxity had a heterozygous collagen type VI aspartic to glutamic acid (COL6A3 c.6360 C>G p.Asp2120Glu) gene change found by whole exome sequencing. The DNA variant was qualified as having strong relevance to the enhanced hypermobility due to prior association of collagen 6 gene changes with myopathy. Conclusions: Dual diagnosis of Ehlers-Danlos syndrome was not assigned because the patient lacked criteria like bruising, unusual scars, or selected dysautonomia symptoms. The concept of a hypermobility spectrum offers advantages for management of its constituent conditions if clinically guided ascertainment and DNA diagnostics are employed. 展开更多
关键词 Hypermobility Spectrum Disorders Down Syndrome Ehlers-Danlos Syndrome DNA Variant Qualification Collagen type VI DNA Change
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Two types of changes in apparent resistivity in earthquake prediction 被引量:30
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作者 DU XueBin1,2 1Lanzhou Institute of Seismology, China Earthquake Administration, Lanzhou 730000, China 2Lanzhou Base of Earthquake Science Institute, China Earthquake Administration, Lanzhou 730000, China 《Science China Earth Sciences》 SCIE EI CAS 2011年第1期145-156,共12页
Two types of changes in apparent resistivity (AR) have been linked to earthquake occurrences. This paper studies the changes and their causes, in detail with the ultimate purpose of developing and assessing a method o... Two types of changes in apparent resistivity (AR) have been linked to earthquake occurrences. This paper studies the changes and their causes, in detail with the ultimate purpose of developing and assessing a method of earthquake (EQ) prediction. The AR changes of the first type (CFT) are considered to be precursors related to earthquakes (EQs); these appear mostly in the medium-term period before EQs and in the short-term period preceding EQs. The changes of the second type (CST) are characterized by a turning anomaly of a long-trend AR variation or the drastically descending/ascending anomaly superimposed on such a variation; these appear synchronously in large areas, such as the Chinese mainland, and northern and northwestern China, ect. Their spatio-temporal clusters correspond well to high seismicities in the areas and distant great EQs around the Chinese mainland. Based on the behaviors of the two types of changes, the AR changes observed prior to the Ms8.0 Wenchuan EQ of 2008 are studied. The results show that in the medium-term period before the EQ, noticeable anomalies appeared synchronously at four stations around the Songpan-Ganzi active block, but only weak upward changes were observed in the short-term period preceding the EQ, which caused the prediction of the imminent EQ to fail. 展开更多
关键词 strong earthquake apparent resistivity two types of changes spatio-temporal cluster Wenchuan earthquake
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