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Review of the Water Footprint Project within Geographically Delineated Area
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作者 Stella Symeonidou Dimitra Vagiona 《Journal of Environmental Science and Engineering(B)》 2015年第10期513-520,共8页
During the last decade, there has been an intensive research activity concerning the concept of the Water Footprint (WF) approach, which was firstly introduced by Arjen Hoekstra in 2002. WF is an indicator of direct... During the last decade, there has been an intensive research activity concerning the concept of the Water Footprint (WF) approach, which was firstly introduced by Arjen Hoekstra in 2002. WF is an indicator of direct and indirect freshwater use of a consumer or producer that takes into account water consumption in every step (intermediate and final) along the production chain and services. The concept can be implemented in various levels such as products, consumers, producers, nations and river basins etc.. The water footprint within a geographically delineated area equals the sum of the process water footprints of all processes taking place in the area. The aim of current research is a review of the most important WF studies, with a special focus on applications within regional, basin and administrative unit level. National and global scales are not included in the current paper. The article presents the most widespread methodologies and approaches that attempt to evaluate water footprints of specific defined areas and highlights their recent advances as well as shortcomings in the constantly evolving research efforts. 展开更多
关键词 Water footprint REVIEW water resources management geographically delineated area.
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Application of the DITAPH model coupling human activities and groundwater dynamics for nitrate vulnerability assessment:A case study in Quanzhou,China
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作者 Jian-feng Li Yuan-jing Zhang +4 位作者 Ya-ci Liu Qi-chen Hao Chun-lei Liu Sheng-wei Cao Zheng-hong Li 《Journal of Groundwater Science and Engineering》 2026年第1期32-48,共17页
To address the deficiencies in comprehensive surface contamination prevention strategies within China's nitrate-affected regions,this research innovatively proposes the DITAPH model-a systematic framework integrat... To address the deficiencies in comprehensive surface contamination prevention strategies within China's nitrate-affected regions,this research innovatively proposes the DITAPH model-a systematic framework integrating groundwater nitrate vulnerability assessment and Nitrate Vulnerable Zones(NVZs)delineation through optimization of hydrogeological parameters.Based on detailed hydrogeological and hydrochemical investigations,the DITAPH model was applied in the plain areas of Quanzhou to evaluate its applicability.The model selected hydrogeological parameters(depth of groundwater,lithology of the vadose zone,topographic slope,aquifer water yield property),one climatic parameter(precipitation),and two anthropogenic parameters(land use type and population density)as assessment indicators.The results of the groundwater nitrate vulnerability assessment showed that the low,relatively low,relatively high,and high groundwater nitrate vulnerability zones in the study area accounted for 5.96%,35.44%,53.74%and 4.86%of the total area,respectively.Groundwater nitrate vulnerability was most strongly influenced by human activities,followed by groundwater depth and topographic slope.The high vulnerability zone is mainly affected by domestic and industrial wastewater,whereas the relatively high groundwater nitrate vulnerability zone is primarily influenced by agricultural activities.Validation of the DITAPH model revealed a significant positive correlation between the DITAPH index(DI)and nitrate concentration(ρ(NO3−)).The results of the NVZs delineated by the DITAPH model are reliable and can serve as a tool for water resource management planning,guiding the development of targeted measures in the NVZs to prevent groundwater contamination. 展开更多
关键词 Nitrate contamination NVZs delineation Human activity coupling Pollution risk management
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Species status and genetic isolation in the Subalpine Warbler complex:Insights from mitochondrial DNA analysis
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作者 Utku Perktas Andrew G.Gosler 《Avian Research》 2025年第4期811-817,共7页
This study investigates the genetic differentiation and gene flow within the Subalpine Warbler(Curruca cantillans)complex using mitochondrial DNA(mtDNA)analysis.We focused on three primary populations based on phyloge... This study investigates the genetic differentiation and gene flow within the Subalpine Warbler(Curruca cantillans)complex using mitochondrial DNA(mtDNA)analysis.We focused on three primary populations based on phylogenetic findings and geographical distributions.Popl:Includes C.c.albistriata(distributed in extreme northeast Italy(Trieste),southern Slovenia,and south along the north Adriatic coast to Albania,as well as east to southern Bulgaria,Greece,Crete,and western Turkey,with non-breeding grounds in the central and eastern Sahel from eastern Mali to northwest Sudan)and C.c.cantillans(occurring in Sicily,central and southern Italy,and locally in north-central Italy,with non-breeding grounds presumably in the western Sahel).Pop2:Represents C.iberiae,found in Spain and western France.Pop3:Comprises C.subalpina,distributed across the Balearic Islands,Corsica,Sardinia,some Tuscan islands,and north and central Italy,with non-breeding grounds extending into the western Sahel,reaching northern Nigeria and Niger.Our genetic analysis indicates that all three populations have expanded recently but maintain unique genetic structures.Despite this recent expansion,the populations exhibit limited genetic diversity.Using AMOVA,we found that most genetic variation is between populations rather than within them,indicating significant genetic differentiation.This study uniquely combines population genetic data with advanced analyses to provide detailed insights into the genetic structure and connectivity of the Subalpine Warbler complex,highlighting the distinct genetic lineages within the Mediterranean biodiversity hotspot. 展开更多
关键词 BIOGEOGRAPHY Conservation Genetic differentiation Mediterranean birds Mitochondrial DNA Species delineation
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Analysis and Monitoring of Changes in the Central Marshland Area of Southern Iraq Utilizing Remote Sensing Techniques
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作者 Emad Ali Al-Helaly Israa J.Muhsin +2 位作者 Ebtesam F.Khanjer Ban A.Alrazaq Sundus A.Abdullah Albakry 《Research in Ecology》 2025年第3期296-308,共13页
The marshes of southern Iraq are of great value due to their roles in the economy,environment,heritage,tourism,and agriculture.However,the region has witnessed remarkable transformations in land cover,influenced by hu... The marshes of southern Iraq are of great value due to their roles in the economy,environment,heritage,tourism,and agriculture.However,the region has witnessed remarkable transformations in land cover,influenced by human interventions and natural environmental factors.In this research,the Central Marshlands were selected for study and monitoring.These Marshes form the Mesopotamian Marshes,a vital part of the Tigris-Euphrates river system.This area 2 formerly covered an area of approximately 3,000 km and was once home to the lives of Marsh Arabs and their animals.The primary objective of this study was to compile a set of satellite images covering the same marshland region over several decades.The data used includes images captured by various Landsat missions:MSS(1975),TM(1983&1993),ETM+(2003),and the Operational Land Imager(OLI)from Landsat 8(2015).Satellite images were combined and pre-processed through steps such as layer stacking to create composite images from multiple bands.Several image classification methods were applied,and the classification results showed a significant and unprecedented increase in the percentage of water in the marsh,reaching 16%in 2003.This was combined with vegetation identification techniques,including the identification of vegetation boundaries to detect areas of dense vegetation.In addition,the relative depth of the water was measured to estimate marsh water levels,with the best result obtained in 2003.The normalized mean vegetation index(NDVI)calculated in this study had its best value in 1984 due to the spread of reeds and papyrus during this period.Papyrus is the raw material in the sugar industry,providing a significant economic boost. 展开更多
关键词 MARSHLAND Image Classification NDVI Vegetation Delineation Relative Water Depth
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Perturbation Mechanism and Response Measure of Weight Uncertainties on the Optimized Delineation of Production-living-ecological Space:A Case Study of Xuzhou,China
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作者 LI Xin ZHAO Zilong +2 位作者 MA Xiaodong ZHANG Jian XU Haibin 《Chinese Geographical Science》 2025年第4期835-851,共17页
As the core of spatial planning in China,delineation of the production-living-ecological space(PLES)refers to dividing the overall land use into three functional spaces.Spatial units are optimally configured as the mo... As the core of spatial planning in China,delineation of the production-living-ecological space(PLES)refers to dividing the overall land use into three functional spaces.Spatial units are optimally configured as the most suitable functional type,while beset by various uncertainties.Weight uncertainties,being affected by subjective preferences,are highly arbitrary and seriously affect PLES.Taking Xuzhou as the study area,this paper studies the perturbation mechanism and response measure of weight uncertainties on PLES.First,weight samples are obtained through quasi-random sampling to serve as sources of uncertainties for input into the optimized delineation of PLES.Next,the Monte Carlo simulation is applied to simulate the spatial probability distribution of PLES.The global sensitivity analysis method is then adopted to identify the main sources that cause uncertainties in the delineation of PLES.Subsequently,the flexible space(FS)of PLES at a certain level of significance is formulated by comparing the distribution probabilities of spatial units for different functional spaces,acting as a countermeasure for the perturbation.The results show that weight uncertainties bring disturbances to the PLES by affecting the multi-criteria evaluation(MCE)of PLES delineation.The PLES is affected by the weight uncertainties of the factors alone or through interactions with other weights.FS is the spatial response measure of PLES when uncertainties occurred at a certain level of significance.The study introduces the perspective of uncertainty for PLES,which contributes toward improving the scientificity and reliability of PLES. 展开更多
关键词 weight uncertainties optimal delineation production-living-ecological space(PLES) propagation of uncertainties sensitivity analysis flexible space Xuzhou China
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PD-L1 targeted iron oxide SERS bioprobe for accurately detecting circulating tumor cells and delineating tumor boundary
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作者 Ting Pan Dinghu Zhang +10 位作者 Guomei You Xiaoxia Wu Chenguang Zhang Xinyu Miao Wenzhi Ren Yiwei He Lulu He Yuanchuan Gong Jie Lin Aiguo Wu Guoliang Shao 《Chinese Chemical Letters》 2025年第1期408-414,共7页
Early diagnosis and accurate boundary delineation are the key steps of tumor precision medicine.Circulating tumor cells(CTCs)detection of liquid biopsy can provide abundant information for early diagnosis of cancer.Hi... Early diagnosis and accurate boundary delineation are the key steps of tumor precision medicine.Circulating tumor cells(CTCs)detection of liquid biopsy can provide abundant information for early diagnosis of cancer.High detection specificity and good enrichment features are two key factors for CTCs accurate identification in peripheral blood sample.For this purpose,iron oxide(IO)-based surface-enhanced Raman scattering(SERS)bioprobes with good biocompatibility,high detection sensitivity,remarkable detection specificity,and good enrichment efficiency,were developed for detecting different types of CTCs.Magnetic SERS bioprobes combined with programmed death ligand-1(PD-L1)antibody are regarded as an effective way to boost the targeting ability and detection specificity,benefiting for accurately capturing and identifying rare CTCs.Four types of CTCs with different PD-L1 expression were accurately distinguished among white blood cells via high-resolution SERS mapping images and stable Raman signals.Subsequently,CTCs blood samples obtained from the triple negative breast cancer patients were also successfully recognized compared to that of health people,indicating IO@AR@PDA-a PD-L1 SERS bioprobe possessed great potential for CTCs detection in liquid biopsy.Additionally,IO-based bioprobe exhibited excellent dual-modal imaging abilities of high-resolution SERS imaging mode and microimaging magnetic resonance imaging mode.These two highly complementary imaging modes endowed IO-based bioprobes unrivalled capacity in tumor boundary differentiation,supporting tumor accurate resection and precise surgery.To our best knowledge,this is the first time that biocompatible IO-based SERS bioprobes without noble metal element were reported not only for CTCs accurate detection,but also for precise tumor boundary delineation,showing great advantages in tumor diagnosis and treatment. 展开更多
关键词 Circulating tumor cells Surface-enhanced Raman scattering PD-L1 Iron oxide bioprobe Dual-modal imaging Tumor boundaries delineation
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Application of HEC-HMS for flood forecasting in Misai and Wan'an catchments in China 被引量:12
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作者 James Oloche OLEYIBLO 《Water Science and Engineering》 EI CAS 2010年第1期14-22,共9页
The hydrologic model HEC-HMS (Hydrologic Engineering Center, Hydrologic Modeling System), used in combination with the Geospatial Hydrologic Modeling Extension, HEC-GeoHMS, is not a site-specific hydrologic model. A... The hydrologic model HEC-HMS (Hydrologic Engineering Center, Hydrologic Modeling System), used in combination with the Geospatial Hydrologic Modeling Extension, HEC-GeoHMS, is not a site-specific hydrologic model. Although China has seen the applications of many hydrologic and hydraulic models, HEC-HMS is seldom applied in China, and where it is applied, it is not applied holistically. This paper presents a holistic application of HEC-HMS. Its applicability, capability and suitability for flood forecasting in catchments were examined. The DEMs (digital elevation models) of the study areas were processed using HEC-GeoHMS, an ArcView GIS extension for catchment delineation, terrain pre-processing, and basin processing. The model was calibrated and verified using historical observed data. The determination coefficients and coefficients of agreement for all the flood events were above 0.9, and the relative errors in peak discharges were all within the acceptable range. 展开更多
关键词 hydrologic model HEC-HMS catchment delineation DEM terrain pre-processing Misai Catchment Wan 'an Catchment
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Exploration and research progress on ion-adsorption type REE deposit in South China 被引量:11
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作者 Deng-hong Wang Zhi Zhao +4 位作者 Yang Yu Jing-jing Dai Mao-chun Deng Ting Zhao Li-jun Liu 《China Geology》 2018年第3期415-424,共10页
Since 2011,certain advances have been made through the resource investigation,metallogenesis research,mining supervision and environmental protection of ion-adsorption type rare earth element (REE) deposit in South Ch... Since 2011,certain advances have been made through the resource investigation,metallogenesis research,mining supervision and environmental protection of ion-adsorption type rare earth element (REE) deposit in South China.Firstly,some progress has been made in REE prospecting in Jiangxi,Guangdong,Guangxi and Yunnan.REE deposits are not only found within the weathering crusts of granites and felsic volcanic rocks,but also within the weathering crusts of epimetamorphic rocks and basic magmatic rocks.Secondly,the methods of exploration,delineating ore bodies and calculation of reserves have been improved,which intuitively reflect the thickness,REE composition and value of weathering crust.Thirdly,the relationship between REEs and weathering degree and the rule of distribution,migration and enrichment of REEs in the weathering profile was summarized through the analysis of big data,which can predict the metallogenetic horizon of REEs.Fourthly,a method for quick,accurate and dynamic investigation of the REE deposit has been established by using high resolution remote sensing technology.Finally,the relation between the production status of REE mines and water pollution has been revealed based on long-term hydrochemical monitoring data of rivers and wells in mines and surrounding areas. 展开更多
关键词 Ion-adsorption TYPE REE deposit REE PROSPECTING Ore delineation method High resolution remote sensing technology Hydrochemical monitoring
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A Method for Alpine Wetland Delineation and Features of Border: Zoigê Plateau, China 被引量:3
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作者 ZHENG Yaomin NIU Zhenguo +12 位作者 GONG Peng LI Mengna HU Lile WANG Lei YANG Yuxiang GU Hai-jun MU Jinrong DOU Gejia XUE Hui WANG Lin LI Hua DOU Gejie DANG Zhicairang 《Chinese Geographical Science》 SCIE CSCD 2017年第5期784-799,共16页
Accurate wetland delineation is the basis of wetland definition and mapping, and is of great importance for wetland management and research. The Zoige Plateau on the Qinghai-Tibet Plateau was used as a research site f... Accurate wetland delineation is the basis of wetland definition and mapping, and is of great importance for wetland management and research. The Zoige Plateau on the Qinghai-Tibet Plateau was used as a research site for research on alpine wetland delineation. Several studies have analyzed the spatiotemporal pattern and dynamics of these alpine wetlands, but none have addressed the issues of wetland boundaries. The objective of this work was to discriminate the upper boundaries of alpine wetlands by coupling ecological methods and satellite observations. The combination of Landsat 8 images and supervised classification was an effective method for rapid identification of alpine wetlands in the Zoig6 Plateau. Wet meadow was relatively stable compared with hydric soils and wetland hydrology and could be used as a primary indicator for discriminating the upper boundaries of alpine wetlands. A slope of less than 4.5° could be used as the threshold value for wetland delineation. The normalized difference vegetation index (NDVI) in 434 field sites showed that a threshold value of 0.3 could distinguish grasslands from emergent marsh and wet meadow in September. The median normalized difference water index (NDWI) of emergent marsh remained more stable than that of wet meadow and grasslands during the period from September until July of the following year. The index of mean density in wet meadow zones was higher than the emergent and upland zones. Over twice the number of species occurred in the wet meadow zone compared with the emergent zone, and close to the value of upland zone. Alpine wetlands in the three reserves in 2014 covered 1175.19 kin2 with a classification accuracy of 75.6%. The combination of ecological methods and remote sensing technology will play an important role in wetland delineation at medium and small scales. The correct differentiation between wet meadow and grasslands is the key to improving the accuracy of future wetland delineation. 展开更多
关键词 alpine wetland delineation ecological methods remote sensing Zoige Plateau
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Integrative taxonomy of Leptonetela spiders (Araneae, Leptonetidae), with descriptions of 46 new species 被引量:3
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作者 Chun-Xia Wang Xin Xu Shu-Qiang Li 《Zoological Research》 CAS CSCD 2017年第6期321-448,共128页
Extreme environments, such as subterranean habitats, are suspected to be responsible for morphologically inseparable cryptic or sibling species and can bias biodiversity assessment. A DNA barcode is a short, standardi... Extreme environments, such as subterranean habitats, are suspected to be responsible for morphologically inseparable cryptic or sibling species and can bias biodiversity assessment. A DNA barcode is a short, standardized DNA sequence used for taxonomic purposes and has the potential to lessen the challenges presented by a biotic inventory. Here, we investigate the diversity of the genus Leptonetela Kratochvil, 1978 that is endemic to karst systems in Eurasia using DNA barcoding. We analyzed 624 specimens using one mitochondrial gene fragment (COl). The results show that DNA barcoding is an efficient and rapid species identification method in this genus. DNA barcoding gap and automatic barcode gap discovery (ABGD) analyses indicated the existence of 90 species, a result consistent with previous taxonomic hypotheses, and supported the existence of extreme male pedipalpal tibial spine and median apophysis polymorphism in Leptonetela species, with direct implications for the taxonomy of the group and its diversity. Based on the molecular and morphological evidence, we delimit and diagnose 90 Leptonetela species, including the type species Leptonetela kanellisi (Deeleman-Reinhold, 1971). Forty-six of them are previously undescribed. The female of Leptonetela zhai Wang & Li, 2011 is reported for the first time. Leptonetela tianxinensis (Tong & Li, 2008) comb. nov. is transferred from the genus Leptoneta Simon, 1872; the genus Guineta Lin & Li, 2010 syn. nov. is a junior synonym of Leptonetela; Leptonetela gigachela (Lin & Li, 2010) comb. nov. is transferred from Guineta. The genus Sinoneta LJn & Li, 2010 syn. nov. is a junior synonym of Leptonetela; Leptonetela notabilis (Lin & Li, 2010) comb. nov. and Leptonetela sexdigiti (Lin & Li, 2010) comb. nov. are transferred from Sinoneta; Leptonetela sanchahe Wang & Li nom. nov. is proposed as a replacement name for Sinoneta palmata (Chen et a 2010) because Leptonetela palmata is preoccupied. 展开更多
关键词 DNA barcoding PHYLOGENY Phenotype Species delineation
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Automatic Delineation of Lung Parenchyma Based on Multilevel Thresholding and Gaussian Mixture Modelling 被引量:2
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作者 S.Gopalakrishnan A.Kandaswamy 《Computer Modeling in Engineering & Sciences》 SCIE EI 2018年第2期141-152,共12页
Delineation of the lung parenchyma in the thoracic Computed Tomography(CT)is an important processing step for most of the pulmonary image analysis such as lung volume extraction,lung nodule detection and pulmonary ves... Delineation of the lung parenchyma in the thoracic Computed Tomography(CT)is an important processing step for most of the pulmonary image analysis such as lung volume extraction,lung nodule detection and pulmonary vessel segmentation.An automatic method for accurate delineation of lung parenchyma in thoracic Computed Tomography images is presented in this paper.The proposed method involves a segmentation phase followed by a lung boundary correction technique.The tissues in the thoracic Computed Tomography can be represented by a number of Gaussians.We propose a histogram utilized Adaptive Multilevel Thresholding(AMT)for estimating the total number of Gaussians and their initial parameters.The parameters of Gaussian components are updated by Expectation Maximization(EM)algorithm.The segmented lung parenchyma from the Gaussian Mixture model(GMM)undergoes an Adaptive Morphological Filtering(AMF)to reduce the boundary errors.The proposed method has been tested on 70 diseased and 119 normal lung images from 28 cases obtained from Lung Image Database Consortium(LIDC).The performance of the proposed system has been validated. 展开更多
关键词 Lung PARENCHYMA DELINEATION THORACIC COMPUTED tomography MULTILEVEL THRESHOLDING Gaussian mixture model Adaptive Morphological Filtering
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Positron emission tomography and magnetic resonance imaging combined with computed tomography in tumor volume delineation: A case report 被引量:3
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作者 Qi-Ping Zhou Yu-Hua Zhao Lei Gao 《World Journal of Clinical Cases》 SCIE 2022年第1期249-253,共5页
BACKGROUND Accurate delineation of the target area for patients with hypopharyngeal cancer is the key to achieving an ideal radiotherapy effect.Since computed tomography(CT)alone can no longer meet the treatment needs... BACKGROUND Accurate delineation of the target area for patients with hypopharyngeal cancer is the key to achieving an ideal radiotherapy effect.Since computed tomography(CT)alone can no longer meet the treatment needs,fusing CT images with magnetic resonance imaging(MRI)or positron emission tomography(PET)images can overcome the disadvantages of CT.Herein,we present a clinical case of hypopharyngeal cancer to delineate the tumor volume using combined MRI-CT and PET-CT fusion images to examine if they could accurately cover the tumor volume.CASE SUMMARY A 67-year-old male patient with hypopharyngeal carcinoma could not tolerate chemotherapy and surgery due to complicated health issues such as diabetic nephropathy and other underlying diseases.After multidisciplinary consultations,clinicians eventually agreed to undergo radiotherapy to control the progression of his tumor.He was examined by CT,MRI,and 18-fluorodeoxyglucose-PET for treatment planning,and CT images were fused with PET and MRI images while delineating tumor volume.CONCLUSION The image fusion of MRI-CT and PET-CT has both advantages and disadvantages.Compared with CT images alone,the combination of MRI-CT and PET-CT fusion images can precisely cover the gross tumor volume in hypopharyngeal carcinoma and avoid overestimation or incomplete coverage of tumor volume. 展开更多
关键词 Hypopharyngeal carcinoma Computed tomography Magnetic resonance imaging Positron emission tomography Image fusion Tumor volume delineation Case report
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Preliminary considerations on the potential influence of submarine fans on marine delimitation 被引量:2
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作者 QIU Wenxian JIN Xianglong +1 位作者 SCHOFIELD Clive LI Mingbi 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第12期133-142,共10页
The complex issues associated with marine delineation for the outer limit of continental shelf and the boundary delimitation have provoked considerable attention among researchers in a variety of academic circles, par... The complex issues associated with marine delineation for the outer limit of continental shelf and the boundary delimitation have provoked considerable attention among researchers in a variety of academic circles, particularly in the juristic filed and the geo-science field. In the present contribution, we start from an overview of submarine fans, as one of common types of sediment-deposit bodies in the ocean, and ex- plore the related geological features which may be of relevance to the marine delimitation in accordance with the 1982 United Nations Convention on the Law of the Sea. We carry out a comparative assessment of certain significant geological features of submarine fans, using the Bengal fan as an example, which is the biggest submarine fan in the world and represents an important factor in the maritime boundary dispute between the neighboring states currently. The relationship between the special geological bodies and the international principle in the 1982 United Nations Convention can be established by combining geological and juristic analyses. This preliminary observation on the effect of submarine bodies both on the marine entitlement and boundary delimitation indicates that it is important for the international society to appro- priately deal with this problem so that the marine right of any state can be protected. 展开更多
关键词 submarine fan marine delineation ENTITLEMENT Bay of Bengal
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Improving the accuracy and consistency of clinical target volume delineation for rectal cancer by an education program 被引量:2
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作者 Yang-Zi Zhang Xiang-Gao Zhu +7 位作者 Ma-Xiaowei Song Kai-Ning Yao Shuai Li Jian-Hao Geng Hong-Zhi Wang Yong-Heng Li Yong Cai Wei-Hu Wang 《World Journal of Gastrointestinal Oncology》 SCIE 2022年第5期1027-1036,共10页
BACKGROUND Accurate target volume delineation is the premise for the implementation of precise radiotherapy.Inadequate target volume delineation may diminish tumor control or increase toxicity.Although several clinica... BACKGROUND Accurate target volume delineation is the premise for the implementation of precise radiotherapy.Inadequate target volume delineation may diminish tumor control or increase toxicity.Although several clinical target volume(CTV)delineation guidelines for rectal cancer have been published in recent years,significant interobserver variation(IOV)in CTV delineation still exists among radiation oncologists.However,proper education may serve as a bridge that connects complex guidelines with clinical practice.AIM To examine whether an education program could improve the accuracy and consistency of preoperative radiotherapy CTV delineation for rectal cancer.METHODS The study consisted of a baseline target volume delineation,a 150-min education intervention,and a follow-up evaluation.A 42-year-old man diagnosed with stage IIIC(T3N2bM0)rectal adenocarcinoma was selected for target volume delineation.CTVs obtained before and after the program were compared.Dice similarity coefficient(DSC),inclusiveness index(IncI),conformal index(CI),and relative volume difference[ΔV(%)]were analyzed to quantitatively evaluate the disparities between the participants’delineation and the standard CTV.Maximum volume ratio(MVR)and coefficient of variation(CV)were calculated to assess the IOV.Qualitative analysis included four common controversies in CTV delineation concerning the upper boundary of the target volume,external iliac area,groin area,and ischiorectal fossa.RESULTS Of the 18 radiation oncologists from 10 provinces in China,13 completed two sets of CTVs.In quantitative analysis,the average CTV volume decreased from 809.82 cm3 to 705.21 cm3(P=0.001)after the education program.Regarding the indices for geometric comparison,the mean DSC,IncI,and CI increased significantly,whileΔV(%)decreased remarkably,indicating improved agreement between participants’delineation and the standard CTV.Moreover,an 11.80%reduction in MVR and 18.19%reduction in CV were noted,demonstrating a smaller IOV in delineation after the education program.Regarding qualitative analysis,the greatest variations in baseline were observed at the external iliac area and ischiorectal fossa;61.54%(8/13)and 53.85%(7/13)of the participants unnecessarily delineated the external iliac area and the ischiorectal fossa,respectively.However,the education program reduced these variations.CONCLUSION Wide variations in CTV delineation for rectal cancer are present among radiation oncologists in China's Mainland.A well-structured education program could improve delineation accuracy and reduce IOVs. 展开更多
关键词 Rectal cancer RADIOTHERAPY Clinical target volume DELINEATION Interobserver variation EDUCATION
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STUDY ON THE FRACTAL CHARACTER OF MAGNETIC ANOMALY FIELDS AND THE DELINEATION OF TECTONIC ELEMENTS IN THE SOUTH CHINA SEA 被引量:1
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作者 姜效典 于增慧 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1998年第1期28-35,共0页
This is a quantitative method for studying the fractal character of magnetic anornaly fields and delineating tectonic elements using fractal theory . For an area with different geological and geophysical features , th... This is a quantitative method for studying the fractal character of magnetic anornaly fields and delineating tectonic elements using fractal theory . For an area with different geological and geophysical features , the definition of Hausdorff dimension is used to calculate the fractal dimension of the area’s magnetic field , then delineate geological tectonic elements by comparing this value . Use of 1978- 1986 geophysical survey data in this method applied to the South China Sea yielded three first grade tectonic elements and nine second grade ones , in six of which subsecond grade elernents were found. 展开更多
关键词 FRACTAL theory FRACTAL CHARACTER of magnetic anomaly FIELDS DELINEATION of TECTONIC ELEMENTS South China Sea
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Automated tree detection and crown delineation using airborne laser scanner data in heterogeneous East-Central Europe forest with different species mix 被引量:1
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作者 Róbert Smreek Ivan Sakov +1 位作者 Zuzana Michnová Ján Tuek 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第5期1049-1059,共11页
Identifying tree locations is a basic step in the derivation of other tree parameters using remote sensing techniques, particularly when using airborne laser scanning. There are several techniques for identifying tree... Identifying tree locations is a basic step in the derivation of other tree parameters using remote sensing techniques, particularly when using airborne laser scanning. There are several techniques for identifying tree positions. In this paper, we present a raster-based method for determining tree position and delineating crown coverage. We collected data from nine research plots that supported different mixes of species. We applied a raster-based method to raster layers with six different spatial resolutions and used terrestrial measurement data as reference data. Tree identification at a spatial resolution of 1.5 m was demonstrated to be the most accurate, with an average identification ratio (IR) of 95% and average detection ratio of 68% being observed. At a higher spatial resolution of 0.5 m, IR was overestimated by more than 600%. At a lower spatial resolution of 3 m, IR was underestimated at less than 44% of terrestrial measurements. The inventory process was timed to enable evaluation of the time efficiency of automatic methods. 展开更多
关键词 Airborne laser scanning East-Central Europe Individual tree Mixed forest Tree crown delineation
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Spatiotemporal Modeling of Monthly Precipitation in the Upper Shiyang River Watershed in West Central Gansu,Northwest China 被引量:1
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作者 张存杰 C.P.-A.BOURQUE +1 位作者 孙兰东 Q.K.HASSAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2010年第1期185-194,共10页
This paper outlines a methodology to estimate monthly precipitation surfaces at 1-kin resolution for the Upper Shiyang River watershed (USRW) in northwest China. Generation of precipitation maps is based on the appl... This paper outlines a methodology to estimate monthly precipitation surfaces at 1-kin resolution for the Upper Shiyang River watershed (USRW) in northwest China. Generation of precipitation maps is based on the application of a four-variable genetic algorithm (GA) trained on 10 years of weather and ancillary data, i.e., surface air temperature, relative humidity, Digital Elevation Model-derived estimates of elevation, and time of year collected at 29 weather stations in west-central Gansu and northern Qinghai province. An observed-to-GA predicted data comparison of 10 years of precipitation collected at the 29 weather stations showed that about 84% of the variability in observed values could be explained by the trained GA, including variability in two independent datasets. Point-comparisons of observed and modeled precipitation along an elevation-rainfall gradient demonstrated near-similar spatiotemporal patterns. A precipitation surface for USRW for July, 2005, was developed with the trained GA and input surfaces of surface air temperature and relative humidity generated from Moderate Resolution Imaging Spectroradiometer sensor (MODIS) products of land surface temperature. Spatial tendencies in predicted maximum and minimum values of surface air temperature, relative humidity, and precipitation within a 2-kin radius circle around selected weather stations were in close agreement with the values measured at the weather stations. 展开更多
关键词 genetic algorithms model building MODIS products principal component analysis watershed delineation
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Evaluating long-term attachment of two different endoclips in the human gastrointestinal tract 被引量:1
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作者 Hendrik Albert Maurits Swellengrebel Cornelia Adriana Maria Marijnen +1 位作者 Andrew Vincent Annemieke Cats 《World Journal of Gastrointestinal Endoscopy》 CAS 2010年第10期344-348,共5页
AIM:To evaluate the long-term attachment of two types of endoclips in the human gastrointestinal tract. METHODS:In this prospective observational study,endoclips were placed and followed-up during endoscopies or using... AIM:To evaluate the long-term attachment of two types of endoclips in the human gastrointestinal tract. METHODS:In this prospective observational study,endoclips were placed and followed-up during endoscopies or using fluoroscopic images as part of a pro s pective feasibility study evaluating external beam radiotherapy (EBRT,wk 1-3) followed by high dose rate brachytherapy (HDRBT with an endoluminal app licator once a week for 3 wk,wk 9-11) in medically inoperablerectal cancer patients. Initially,the type and number of endoclips were chosenrandomly and later refined to 1 Resolution clip (Microvasive) proximal and 2 Quickclips (Olympus) distal to the tumor. Nine consecutive patients from between September 2007 and August 2008 were analyzed. Retention rates were evaluated over three different observational periods [period 1:pre-HDRBT (wk-2-8),period 2:during HD RBT (wk 9-11) and period 3:post-HDRBT (wk 1216)]. RESULTS:In this study,a total of 44 clips were placed during endoscopy,either at the beginning or at the end of period 1. The Resolution clip had a higher overall retention rate than the Quickclip (P = 0.01). After a median period of 81 d after placement (in period 1),longterm retention rates for the Resolution clip and Quickclip clip were 67% and 35% respectively. CONCLUSION:The Resolution clip has a high retention rate and is useful in situations where long-term attachment to the human gastrointestinal mucosa is warranted. 展开更多
关键词 ENDOCLIP RADIOTHERAPY RETENTION rate Cancer DELINEATION
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Three-dimensional delineation of soil pollutants at contaminated sites: Progress and prospects 被引量:1
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作者 TAO Huan LIAO Xiaoyong +2 位作者 CAO Hongying ZHAO Dan HOU Yixuan 《Journal of Geographical Sciences》 SCIE CSCD 2022年第8期1615-1634,共20页
The precision remediation and redevelopment of contaminated sites are crucial issues for improving the human settlement and constructing a beautiful China. Three-dimensional delineation of soil pollutants at contamina... The precision remediation and redevelopment of contaminated sites are crucial issues for improving the human settlement and constructing a beautiful China. Three-dimensional delineation of soil pollutants at contaminated sites is a prerequisite for precision remediation and redevelopment. However, a contaminated site is a three-dimensional complex system coupling multiple spatial elements above-and under-ground. The complexity incurs high uncertainties about the three-dimensional delineation of soil pollutants based on sparse borehole and spatial statistics and inference models. This paper first systematically reviewed the objectives of fine three-dimensional delineation of soil pollutants, the sampling strategies for soil boring, the commonly used models for delineating soil pollutants, and the relevant cases of applying these models at contaminated sites. We then summarized the effects of borehole data and three-dimensional models on soil pollutants' delineation results from biased characteristics and nonstationary conditions. The present research status and related issues on correcting the biased characteristics and nonstationary conditions were analyzed. Finally, based on the problems and challenges, we suggested the three-dimensional delineation of soil pollutants in the underground “black box” for future research from the following six priority areas: multi-scenarios, nonstationary, non-linearity, multi-source data fusion, multiple model coupling, and the delineation of co-contaminated sites. 展开更多
关键词 contaminated sites soil pollution three-dimensional delineation model sparse and biased nonstationarity
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