Matrix metalloproteinases（MMPs）are members of the metzincin superfamily named after the zinc ion and the conserved methionine residue at the active site.In addition to their role in extracellular matrix（ECM）remode...Matrix metalloproteinases（MMPs）are members of the metzincin superfamily named after the zinc ion and the conserved methionine residue at the active site.In addition to their role in extracellular matrix（ECM）remodeling,these proteinases（in）activate many signaling molecules such as growth factors.展开更多
Several complications of insertion and use of pulmonary artery catheter （PAC）, including catheter entrapment, are recognized during or after cardiac surgery. Early detection is very important. We report a case of PA...Several complications of insertion and use of pulmonary artery catheter （PAC）, including catheter entrapment, are recognized during or after cardiac surgery. Early detection is very important. We report a case of PAC entrapment because the the catheter was accidentally su- tured to the superior vena cava. Bleeding from the thermistor connector was initially detected after surgery because the needle punctured the lumen of thermistor connector. The PAC was removed through re-exploration. Therefore, bleeding from the thermistor connector could early indicate the PAC entrapment. We suggest that abnormal bleeding from the non-injectate lumen ports of PAC should be checked before sternal closure.展开更多
The concept of geographical indication is similar to the idea of authentic medicinal herbs in traditional Chinese medicine. This paper examines the geographical indication (GI) resources of medicinal herbs in the Wuli...The concept of geographical indication is similar to the idea of authentic medicinal herbs in traditional Chinese medicine. This paper examines the geographical indication (GI) resources of medicinal herbs in the Wuling Mountain Area from various perspectives, including geographical indication products, geographical indication trademarks, China s geographical indication products mutually recognized and protected with the EU, geographical indication standards, and the exclusive geographical indication logo. It studies the regional public brand characteristics of Chinese authentic medicinal herbs, based on hometown of authentic Chinese medicinal herbs, advantageous regions of characteristic agricultural products, important agricultural cultural heritage, national famous and excellent new agricultural products, national characteristic agricultural products, geographical indication Chinese well-known trademarks, advantageous regions of characteristic agricultural products, and regional public brands of agricultural products. It analyzes the main problems in the protection of geographical indications and the creation of regional public brands, and proposes suggestions for building high-quality authentic medicinal herb bases, developing new quality productivity in the authentic medicinal herb industry, implementing regional brand strategies for authentic medicinal herbs, constructing a new development pattern of dual circulation authentic medicinal herbs, etc.展开更多
China’s shipbuilding industry maintained the world’s largest market share in terms of three major indicators for the 16th consecutive year in 2025,according to data released by the Ministry of Industry and Informati...China’s shipbuilding industry maintained the world’s largest market share in terms of three major indicators for the 16th consecutive year in 2025,according to data released by the Ministry of Industry and Information Technology on 1 February.展开更多
Antibiotics are widespread in aquatic environments due to their extensive use in human healthcare and ani-mal husbandry.However,research on the occurrence and bioaccumulation of antibiotics in aquatic organisms within...Antibiotics are widespread in aquatic environments due to their extensive use in human healthcare and ani-mal husbandry.However,research on the occurrence and bioaccumulation of antibiotics in aquatic organisms within shallow wetland lakes remains limited.This study investigated the occurrence and bioaccumulation of ten commonly used antibiotics in the Baiyang Lake,northern China’s largest shallow wetland lake.The results indicated that sulfonamides and fluoroquinolones were the predominant antibiotics in surface water,whereas fluoroquinolones and macrolides were more prevalent in sediment.Fluoroquinolones demonstrated significant potential for bioaccumulation in targeted aquatic organisms,including both animals and plants(Carassius au-ratus and Phragmites australis).The bioaccumulation of antibiotics in Carassius auratus was correlated with their solubility,whereas in Phragmites australis,this was associated with their octanol-water partition coefficients and molecular weights.Ecological risk assessment indicated that most antibiotics posed minimal to low risk levels.However,four antibiotics were exceptions:clarithromycin(12.5%)and sulfamethoxazole(6.25%)presented a high risk in surface water samples,while norfloxacin(25.0%)and ciprofloxacin(25.0%)posed a high risk in sediment samples.Norfloxacin,ciprofloxacin,and roxithromycin were identified as key indicator antibiotics for enhancing the local monitoring and control of antibiotic contamination based on four criteria:(1)high con-centrations,(2)frequent detection,(3)capacity for bioaccumulation,and(4)ecological risk levels.This study contributes to a deeper understanding of the status of antibiotic contamination,bioaccumulation characteristics,and ecological risk in Baiyang Lake,thereby supporting efforts to monitor and regulate antibiotic pollution.展开更多
Objective:To analyze the therapeutic effect of laparoscopy combined with choledochoscopy in the treatment of difficult cholelithiasis.Methods:A total of 60 patients with difficult cholelithiasis admitted for treatment...Objective:To analyze the therapeutic effect of laparoscopy combined with choledochoscopy in the treatment of difficult cholelithiasis.Methods:A total of 60 patients with difficult cholelithiasis admitted for treatment from January 2022 to December 2024 were selected and evenly divided into two groups using a random number table.The combined group received laparoscopy combined with choledochoscopy treatment,while the single group received laparoscopy treatment alone.The total treatment efficacy,perioperative indicators,angiotensin(Ang)levels,quality of life scores,and complication rates were compared between the two groups.Results:The total treatment efficacy in the combined group was higher than that in the single group;except for operative time,the perioperative indicators in the combined group were superior to those in the single group;the Ang levels after treatment in the combined group were lower than those in the single group,and the quality of life scores were higher(P<0.05).The complication rate in the combined group was lower than that in the single group(P<0.05).Conclusion:Laparoscopy combined with choedochoscopy can enhance the treatment effectiveness for patients with difficult cholelithiasis,improve perioperative indicators,regulate their Ang levels,elevate quality of life,and demonstrate high surgical safety.展开更多
Recently,the China National Intellectual Property Administration released the"List of Enterprises Approved to Use the Geographical Indication Logo."The"Wujiang Silk"geographical indication logo has...Recently,the China National Intellectual Property Administration released the"List of Enterprises Approved to Use the Geographical Indication Logo."The"Wujiang Silk"geographical indication logo has been renewed and launched.This official approval serves to distinguish and celebrate the quality and cultural heritage of Shengze silk,and the use of this symbol is a testament to that distinction.Three enterprises from Shengze have been approved to use the logo:Saint Joy,Huajia Silk,and Xinmin Silk.展开更多
The fine-scale characterization of vegetation surface information serves as a fundamental basis for studying the spatial distribution of resources and the dynamic patterns of environmental responses.Accurately extract...The fine-scale characterization of vegetation surface information serves as a fundamental basis for studying the spatial distribution of resources and the dynamic patterns of environmental responses.Accurately extracting the distributions of different crop species is of critical importance for improving agricultural production efficiency and ensuring food security.Traditional fine-scale vegetation extraction methods often face significant challenges due to the presence of spectrally similar features and the substantial influence of background interference,which limit their applicability across large areas.As a key phenological stage of angiosperms,flowering is characterized by distinctive flowering times,floral morphology,and canopy spectral signatures,so it is an effective pathway for fine-scale vegetation extraction using remote sensing.Using rapeseed as an example,this study developed a spectral index model for precise flowering vegetation extraction(FI-R)based on Landsat OLI imagery.The model integrates a yellowness index(Blue,Green)and a peak index(Red,Nir and SWIR1)while leveraging the NDVI to mitigate background interference from spectrally similar objects.This approach successfully enables the rapid and accurate large-scale mapping of flowering vegetation under complex background conditions.The proposed method was tested in five rapeseed cultivation regions worldwide with diverse backgrounds.Validation datasets were generated using GF imagery and the U.S.CDL dataset.The FI-R model demonstrated superior capability in distinguishing flowering rapeseed from other vegetation,and achieved overall accuracies exceeding 94%in all study areas.Furthermore,FI-R is compatible with other multispectral sensors that have similar band configurations,so it is applicable to rapeseed extraction in broader contexts.The method also shows strong potential for the fine-scale extraction of other types of flowering angiosperm vegetation.展开更多
Objective:To investigate the spatial gradient of intraoperative impedance across the cochlear electrode array in pediatric cochlear implant recipients and assess its potential as a physiological indicator for the elec...Objective:To investigate the spatial gradient of intraoperative impedance across the cochlear electrode array in pediatric cochlear implant recipients and assess its potential as a physiological indicator for the electrode-neural interface.Methods:A prospective observational study involving 56 pediatric patients underwent cochlear implantation with Cochlear Nucleus devices.Intraoperative polarized impedance and electrically evoked compound action potential(ECAP)threshold were recorded across all 1232 electrodes using AutoNRT software.Eight electrodes with open-or short-circuit were excluded,leaving 1,224 for analysis.Impedance values were categorized by cochlear region(basal,middle,apical),and electrodes with elevated impedance(10-20 kΩ)were analyzed for regional distribution and clinical relevance.Data were analyzed for spatial patterns and correlation with the ECAP threshold profiles.Results:A consistent basal-to-apical increase in impedance was observed(7.7±1.9,9.2±1.4,10.8±1.5 kΩ;p<0.001).Impedance and ECAP threshold were weakly correlated(ρ=-0.20,p<0.001;β=-1.26,p<0.001),with a positive association in the apical region(ρ=0.12,p=0.048).Electrodes with higher impedance(1020 kΩ)were less likely to show elevated or absent TNRT(OR=0.175,p=0.02).The impedance gradient persisted across age groups and was significantly correlated with ECAP threshold patterns.Conclusion:Intraoperative impedance monitoring reveals a strong and physiologically consistent gradient,with higher values in apical electrodes.This gradient reflects anatomical and tissue interface variations,which may offer a valuable physiological indicator for intraoperative electrode positioning and neural interface integrity.展开更多
Engineering problems often involve large spatial scales and long-term lifespans.This makes it exceptionally difficult to measure engineering parameters and predict disasters such as slope instability or tunnel collaps...Engineering problems often involve large spatial scales and long-term lifespans.This makes it exceptionally difficult to measure engineering parameters and predict disasters such as slope instability or tunnel collapses.A key challenge is to calculate large-scale(target lifespan)quantitative indicators from small-scale(short-term)detectable results,thereby enhancing engineering safety and economic efficiency.Many engineering problems exhibit a unidirectional spatio-temporal evolution with either decay or enhancement as their spatial scale or time increases.This phenomenon is called the power law with exponential function.A general approach is required to use this evolution law in the prediction of the unknown from the known.This paper proposes a novel concept to calculate large-scale indicators via variation of small-scale data(called CLIVS for short),to address a general approach through the following five aspects:Firstly,general spatio-temporal evolution laws in engineering are systematically summarized and classified.Then,the core idea and basic concepts of CLIVS,its mathematical formulation and solution procedure are described in detail.Thirdly,the linkage of CLIVS to past famous philosophy schools is explored.Fourthly,the potential applications of CLIVS to rock mechanics and rock engineering are classified according to size effect and time-scale law.Finally,two typical examples of the application of CLIVS to engineering parameter prediction are presented.These demonstrate that the CLIVS provides a novel way and a general approach to accurately predict unknown behaviors based on known local spatial data or short-term indicators.It formulates a unified theoretical framework or universal approach to calculate unmeasurable engineering parameters or predict lifespan with reasonable accuracy from the knowns measurable at the local scale or in the short term.展开更多
Urban geochemical alteration and transformation are complex processes that affect air,water,and soil,potentially posing serious health risks to the residents.Our health is determined by where we live now,and where we ...Urban geochemical alteration and transformation are complex processes that affect air,water,and soil,potentially posing serious health risks to the residents.Our health is determined by where we live now,and where we have previously lived and how long we have been there.This review explores patterns of urban environmental pollution and public health risks associated with potentially harmful elements.Academic databases including Scopus,Web of Science,and Google Scholar were used to find pertinent peer-reviewed papers,reports,and case studies.It discusses urban environmental and medical geochemistry,focusing on toxic heavy metals of public health concern and their urban sources.Case studies on geochemical anomalies in street dust,atmospheric,lithochemical,and hydrochemical contexts are critically examined.The review evaluates the effectiveness of geochemical indices in assessing pollution and health risk patterns in road dust,soil,air,and water,emphasizing the importance of geochemical background in urban geochemistry and medical geology.Strategies to reduce toxic heavy metal pollution in urban areas are also reviewed to protect public health.Finally,it offers conclusions and recommendations for future research.It is obvious that the environmental geochemistry of soil,street dust,water,and air contain a wealth of information about the state of urban environments.The outcomes of this study will help to raise public awareness of urban pollution and associated health risks,promoting environmental preservation and health protection in urban settings.展开更多
Securitization of economies has received much attention in urban and regional studies,as how the city economy has connected with the capital markets has been increasingly important for a city’s development.This study...Securitization of economies has received much attention in urban and regional studies,as how the city economy has connected with the capital markets has been increasingly important for a city’s development.This study develops a modified Buffett indicator,calculating the ratio of total market capitalization of listed companies to the gross domestic product(GDP)of the city in which these companies are headquartered,to measure city securitization rates(CSR).Drawing on this indicator,this study maps the CSR of all prefecture-and-above level cities in China.It is found that cities with high CSR in China are mainly financial centers and some resource-based cities,while most other cities’CSR are quite low.The regression results show that city’s innovation capacity and political status are positively and significantly associated with the CSR in China.In addition,being close to financial centers can significantly improve the CSR of cities in the eastern region of the country.With the growing financialization of societies,the modified Buffett indicator has a potential to explore the city economy from the perspective of its connection with capital markets in future research.展开更多
This study investigates the turbulence-induced disturbances and stall precursor triggering mechanism in NACA65-18(10)cascade based on large eddy simulations.The results indicate that the disturbances exist under vario...This study investigates the turbulence-induced disturbances and stall precursor triggering mechanism in NACA65-18(10)cascade based on large eddy simulations.The results indicate that the disturbances exist under various operating conditions along the performance curve.The shear layer is the physical structure responsible for the generation,propagation,and dissipation of disturbances.When operating near stall,the separation on the suction surface intensifies,and strong unsteady backflow occurs at the trailing edge of the passage.Under the influence of inlet disturbances,unsteady behaviors between passages form specific phase differences,leading the entire system to oscillate in a first-order mode.As the flow develops from near-stall to stall,axial momentum decreases further,reducing the main flow’s ability to drive blockages downstream through convection.Consequently,the blockage accumulates during the circumferential propagation process until the stall onset.Based on the above mechanism,this study proposes factors describing the size of the backflow zone,shedding frequency,and convection velocity to characterize blockage dynamics,identifying critical values that represent the stall onset.展开更多
Agricultural Intangible Cultural Heritage(AICH)embodies collective,intergenerational knowledge sys⁃tems that are increasingly exposed to risks of misappropriation and inequitable commercialization under contemporary i...Agricultural Intangible Cultural Heritage(AICH)embodies collective,intergenerational knowledge sys⁃tems that are increasingly exposed to risks of misappropriation and inequitable commercialization under contemporary intellectual property(IP)regimes.This study investigates the"cost of inaction"in protecting AICH and geographical origins through a qualitative comparative case study approach,drawing on selected cases from Africa,Asia,and Latin America,alongside Chinese practices.By combining narrative analysis and thematic synthesis,the study identi⁃fies two dominant patterns:external misappropriation driven by institutional gaps-manifested in biopiracy,trademark squatting,and exploitation of information asymmetry-and internal inequities arising from commercialization processes that marginalize indigenous communities in benefit-sharing.The findings reveal that existing international IP frame⁃works,including TRIPs and the CBD,provide fragmented and insufficient protection for collective knowledge sys⁃tems.Comparative analysis of national responses highlights three distinct governance models:defensive protection(In⁃dia),rights-based sui generis legislation(Peru),and market-oriented geographical indication systems(European Union),each with inherent limitations.In contrast,Chinese practices demonstrate strong capacity in market integra⁃tion and industrial upgrading but remain constrained by weak recognition of community rights and limited institutional⁃ization of benefit-sharing mechanisms.This study contributes to the literature by proposing a composite institutional framework that integrates existing IP regimes with a sui generis system centered on collective rights recognition,prior informed consent,and mandatory benefit-sharing.The framework also emphasizes the need for embedded integration with patent,trademark,and geographical indication systems,as well as institutional adaptation in the context of the digital economy.The findings offer theoretical insights and policy implications for developing countries seeking to bal⁃ance cultural preservation,economic development,and equitable governance of traditional knowledge.展开更多
BACKGROUND Inappropriate selection of patients with early gastric cancer(EGC)for endoscopic submucosal dissection(ESD)may lead to non-curative resection,necessitating additional gastrectomy.Conversely,inappropriate se...BACKGROUND Inappropriate selection of patients with early gastric cancer(EGC)for endoscopic submucosal dissection(ESD)may lead to non-curative resection,necessitating additional gastrectomy.Conversely,inappropriate selection for gastrectomy may result in overtreatment,adversely affecting patients’quality of life.Few have systematically evaluated the concordance between therapeutic indications under current Japanese guidelines and pathological criteria in EGC.To minimize noncurative resection risks while sparing unnecessary surgery for low-risk patients’,we specifically assess the suitability of Japanese guidelines in non-Japanese populations.This work aims to optimize clinical practice by refining endoscopic treatment criteria for adoption beyond Japan.AIM To evaluate EGC clinical decision accuracy by comparing therapeutic indication with postoperative pathological criteria and analyzing factors influencing discrepancies.METHODS A retrospective analysis was conducted on 796 EGC cases diagnosed at Peking University Third Hospital between January 2010 and December 2022.Cases were categorized into three groups:Same-estimated(preoperative therapeutic indication with postoperative pathological criteria matched),underestimated(preoperative ESD indication but postoperative surgical criteria),and overestimated(preoperative surgical indication but postoperative ESD criteria).The rate of discrepancy and associated risk factors were assessed.RESULTS The accuracy rates of preoperative evaluation for ESD and gastrectomy indications were 73.0%(321/430)and 76.0%(278/366),respectively.The overall discrepancy rate was 25.6%(204/796).Multivariate analysis identified tumor location in the upper-third stomach(odds ratio=2.158,95%confidence interval:1.373-3.390,P=0.001)was significantly associated with a higher likelihood of being underestimated and undifferentiated histologic type on preoperative biopsy(odds ratio=2.005,95%confidence interval:1.036-3.879,P=0.039)was more likely to be overestimated.Significant differences were observed in tumor diameter(P<0.001),depth of infiltration(P<0.001),ulcerative findings(P<0.001),and histologic type(P<0.001)between preoperative and postoperative evaluations.CONCLUSION The accuracy of preoperative EGC indications is 74.4%.Upper-third stomach and undifferentiated histology are primary discrepancy predictors.Upper-third tumors are prone to underestimation,while undifferentiated tumors are prone to overestimation.展开更多
The Almus Fault Zone(AFZ)is one of the major splay faults of the North Anatolian Fault Zone(NAFZ)and is important for understanding its tectonic features and assessing regional seismic hazards.This research presents t...The Almus Fault Zone(AFZ)is one of the major splay faults of the North Anatolian Fault Zone(NAFZ)and is important for understanding its tectonic features and assessing regional seismic hazards.This research presents the integration of morphometric indices to quantitatively assess the spatial variation of tectonic activity along the AFZ.The AFZ is an active fault with both strike-slip and normal fault components and consists of two main branches,Mercimekdağı-Çamdere Fault(MÇF)and Tokat Fault(TF)segments.This study aims to assess the relative tectonic activity of the AFZ using various morphometric indices,based on a 10 m resolution DEM,with the aid of ArcGIS and MATLAB software.For this purpose,morphometric indices such as hypsometric integral(HI:0.35-0.65),mountain front sinuosity(Smf:1.3-1.44),valley floor width-height ratio(Vf:0.15-2.28),asymmetry factor(AF:23-77),drainage basin shape(Bs:1.13-6.10)and normalized steepness index(ksn:1-498)were applied to 53 drainage basins.When the Smf and mean Vf indices results were evaluated,it was calculated that the uplift ratio of the region was more than 0.5 mm/yr.The spatial distribution of the relative tectonic activity(Iat)of the area was revealed by combining the obtained morphometric indices analysis results.According to the Iat result,it was concluded that the MercimekdağıÇamdere Fault and Tokat Fault segments have high tectonic activity,but the Mercimekdağı-Çamdere Fault segment has higher tectonic activity.The results obtained were also confirmed by field observations.This research provides valuable information for the evaluation of tectonic activity in drainage systems controlled by splay faults.展开更多
Objective:To evaluate and compare coagulation and hematological parameters in hypertensive and normotensive pregnant women.Methods:This present cross-sectional study was carried out in the Departments of Pathology and...Objective:To evaluate and compare coagulation and hematological parameters in hypertensive and normotensive pregnant women.Methods:This present cross-sectional study was carried out in the Departments of Pathology and Obstetrics&Gynaecology at Dr.D.Y.Patil Medical College,Hospital&Research Centre,Pimpri,Pune,India from September 2023 to March 2025.Hematological parameters[platelet count,mean platelet volume(MPV),platelet distribution width(PDW)]were analyzed using an automated hematology analyzer,while coagulation parameters[prothrombin time(PT)/international normalised ratio,activated partial thromboplastin time(aPTT),and D-dimer]were assessed by standard automated assays.Results were compared between normotensive and hypertensive groups and correlated with disease severity.Results:The study included 212 antenatal females,with 106 normotensive pregnant women and 106 hypertensive women.Hypertensive women include cases of gestational hypertension(n=55);mild preeclampsia(n=39),and severe preeclampsia(n=12).A significant progressive decrease in platelet count and significant increases in MPV,PDW,PT,aPTT,and D-dimer levels were associated with increasing severity of pregnancy-induced hypertension(P<0.001).Women with severe preeclampsia had the lowest mean platelet counts and the highest coagulation parameter values compared to women with gestational hypertension,mild preeclampsia,and normotensive pregnancies.These findings indicate enhanced platelet activation,endothelial dysfunction,and activation of the coagulation–fibrinolytic system with worsening disease severity.Conclusions:Significant hematologic and coagulation abnormalities were present in women with pregnancy-induced hypertension.For better maternal-fetal outcomes and early management,routine monitoring is essential.展开更多
Diabetic kidney disease (DKD)is one of the most common and severe microvascular complications of type 2 diabetes mellitus (T2DM). It is also a major cause of end-stage renal disease (ESRD), making early identification...Diabetic kidney disease (DKD)is one of the most common and severe microvascular complications of type 2 diabetes mellitus (T2DM). It is also a major cause of end-stage renal disease (ESRD), making early identification and intervention crucial. Insulin resistance (IR)is a key pathophysiological mechanism of T2DM and plays a central role in the progression of DKD. In recent years, a series of novel surrogate indicators of IR, such as the triglyceride-glucose (TyG) index, TyG-body mass index (TyG-BMI), triglyceride to high-density lipoprotein cholesterol ratio (TG/HDL-C), and metabolic score for insulin resistance (METS-IR), have attracted widespread attention due to their simplicity and cost-effectiveness. This article reviews the research progress of novel surrogate indicators of insulin resistance (IR) in type 2 diabetic kidney disease (DKD), aiming to provide references for the early prevention and improved prognosis of DKD.展开更多
We used solidification/stabilization methods to remediate highly concentrated Zn^(2+)-contaminated soil.An industrial waste mixture of red mud,carbide slag,and phosphogypsum is combined with cement as the curing agent...We used solidification/stabilization methods to remediate highly concentrated Zn^(2+)-contaminated soil.An industrial waste mixture of red mud,carbide slag,and phosphogypsum is combined with cement as the curing agent.The mixing ratios of the four materials are determined by comparing the strength,permeability coefficient,pH,and Zn^(2+)-leaching concentration of the solidified soil.Microscopic characteristics of the solidified uncontaminated soil and solidified Zn^(2+)-contaminated soil were observed using scanning electron microscopy,X-ray diffraction,and Fourier-transform infrared spectroscopy.Furthermore,the heavy metals speciation in both pure cement and mixed-material solidified soil was examined,demonstrating the beneficial role of the mixed-type curing agent in stabilizing heavy metals.The research results indicate that Zn^(2+)degrade the strength of the solidified soil by up to 90%.The permeability coefficient,pH,and Zn^(2+)-leaching concentration of the solidified soil easily meet standard,especially with Zn^(2+)leaching concentration well below the environmental protection limit.Furthermore,most Zn^(2+)exists in forms with lower biological and chemical reactivity.Both the solidified Zn^(2+)-contaminated soil and uncontaminated soil resulted in the formation of hydrated products containing elements such as silicon,aluminum,calcium,and sulfur.Additionally,the solidified Zn^(2+)-contaminated soil produced zinc-containing compounds and a large amount of rod-shaped ettringite.展开更多
The South Aral Seabed is an extreme dryland ecosystem undergoing rapid transformation yet remains misrepresented or absent in global land cover datasets.Conventional vegetation indices,specifically the Normalized Diff...The South Aral Seabed is an extreme dryland ecosystem undergoing rapid transformation yet remains misrepresented or absent in global land cover datasets.Conventional vegetation indices,specifically the Normalized Difference Vegetation Index(NDVI),perform poorly in such environments due to their limited ability to distinguish sparse vegetation from highly reflective saline and sandy soils.This study evaluated the effectiveness of the Modified Soil Adjusted Vegetation Index(MSAVI)for improving land cover classification in the South Aral Seabed and conducted a decadal analysis of land cover change between 2013 and 2023 using Landsat 8 imagery(30 m resolution).A spectral index-based classification framework was developed,combining MSAVI with the Normalized Difference Water Index(NDWI)and Salinity Index 1(SI1)to reduce spectral confusion between vegetation,saline soils,and surface water.The MSAVI-based classification achieved an overall accuracy of 77.96%(Kappa coefficient=0.71),supported by 313 field-collected validation points from 2023.While the multi-index approach enabled finer discrimination of ecologically important classes,particularly separating salt pans from solonchak soils,it resulted in a lower overall accuracy(73.80%),highlighting a trade-off between class separability and classification performance.Land cover change analysis revealed a highly dynamic landscape,with 52.96%of the study area transitioning between classes over the decade.Transformed areas(16,893 km2)exceeded stable zones(15,004 km2),driven primarily by rapid desiccation and salinization.Solonchak soils increased at an annual rate of 5.58%,while surface water bodies declined by 4.83%per year.Concurrently,sparse or distressed vegetation increased by 1.43%annually,reflecting ongoing afforestation efforts.This study provides the first MSAVI-based and medium-resolution land cover baseline for the South Aral Seabed and demonstrates that soil-adjusted vegetation indices are essential for reliable dryland classification where conventional indices fail.The proposed spectral index framework offers a replicable methodology applicable to other global drylands facing similar land degradation and restoration challenges.展开更多
基金supported by the Hercules Foundation(AKUL/09/038&AKUL/13/09)national grants from the Research Council of KU Leuven(BOF-OT/14/064)+1 种基金the Research Foundation Flanders(FWO G0B2315N)the Flemish Institute for the promotion of scientific research(IWT)
文摘Matrix metalloproteinases（MMPs）are members of the metzincin superfamily named after the zinc ion and the conserved methionine residue at the active site.In addition to their role in extracellular matrix（ECM）remodeling,these proteinases（in）activate many signaling molecules such as growth factors.
基金supported by special research program, Ministry of Health, China (200902001)
文摘Several complications of insertion and use of pulmonary artery catheter （PAC）, including catheter entrapment, are recognized during or after cardiac surgery. Early detection is very important. We report a case of PAC entrapment because the the catheter was accidentally su- tured to the superior vena cava. Bleeding from the thermistor connector was initially detected after surgery because the needle punctured the lumen of thermistor connector. The PAC was removed through re-exploration. Therefore, bleeding from the thermistor connector could early indicate the PAC entrapment. We suggest that abnormal bleeding from the non-injectate lumen ports of PAC should be checked before sternal closure.
基金Supported by the Project of National Social Science Fund of China (22CMZ015).
文摘The concept of geographical indication is similar to the idea of authentic medicinal herbs in traditional Chinese medicine. This paper examines the geographical indication (GI) resources of medicinal herbs in the Wuling Mountain Area from various perspectives, including geographical indication products, geographical indication trademarks, China s geographical indication products mutually recognized and protected with the EU, geographical indication standards, and the exclusive geographical indication logo. It studies the regional public brand characteristics of Chinese authentic medicinal herbs, based on hometown of authentic Chinese medicinal herbs, advantageous regions of characteristic agricultural products, important agricultural cultural heritage, national famous and excellent new agricultural products, national characteristic agricultural products, geographical indication Chinese well-known trademarks, advantageous regions of characteristic agricultural products, and regional public brands of agricultural products. It analyzes the main problems in the protection of geographical indications and the creation of regional public brands, and proposes suggestions for building high-quality authentic medicinal herb bases, developing new quality productivity in the authentic medicinal herb industry, implementing regional brand strategies for authentic medicinal herbs, constructing a new development pattern of dual circulation authentic medicinal herbs, etc.
文摘China’s shipbuilding industry maintained the world’s largest market share in terms of three major indicators for the 16th consecutive year in 2025,according to data released by the Ministry of Industry and Information Technology on 1 February.
基金supported by Hebei Natural Science Foundation(No.JZX2023018)Hebei Natural Science Foundation(No.C2022201042)the 100 Foreign Experts Plans of Hebei Province(No.606080123001).
文摘Antibiotics are widespread in aquatic environments due to their extensive use in human healthcare and ani-mal husbandry.However,research on the occurrence and bioaccumulation of antibiotics in aquatic organisms within shallow wetland lakes remains limited.This study investigated the occurrence and bioaccumulation of ten commonly used antibiotics in the Baiyang Lake,northern China’s largest shallow wetland lake.The results indicated that sulfonamides and fluoroquinolones were the predominant antibiotics in surface water,whereas fluoroquinolones and macrolides were more prevalent in sediment.Fluoroquinolones demonstrated significant potential for bioaccumulation in targeted aquatic organisms,including both animals and plants(Carassius au-ratus and Phragmites australis).The bioaccumulation of antibiotics in Carassius auratus was correlated with their solubility,whereas in Phragmites australis,this was associated with their octanol-water partition coefficients and molecular weights.Ecological risk assessment indicated that most antibiotics posed minimal to low risk levels.However,four antibiotics were exceptions:clarithromycin(12.5%)and sulfamethoxazole(6.25%)presented a high risk in surface water samples,while norfloxacin(25.0%)and ciprofloxacin(25.0%)posed a high risk in sediment samples.Norfloxacin,ciprofloxacin,and roxithromycin were identified as key indicator antibiotics for enhancing the local monitoring and control of antibiotic contamination based on four criteria:(1)high con-centrations,(2)frequent detection,(3)capacity for bioaccumulation,and(4)ecological risk levels.This study contributes to a deeper understanding of the status of antibiotic contamination,bioaccumulation characteristics,and ecological risk in Baiyang Lake,thereby supporting efforts to monitor and regulate antibiotic pollution.
文摘Objective:To analyze the therapeutic effect of laparoscopy combined with choledochoscopy in the treatment of difficult cholelithiasis.Methods:A total of 60 patients with difficult cholelithiasis admitted for treatment from January 2022 to December 2024 were selected and evenly divided into two groups using a random number table.The combined group received laparoscopy combined with choledochoscopy treatment,while the single group received laparoscopy treatment alone.The total treatment efficacy,perioperative indicators,angiotensin(Ang)levels,quality of life scores,and complication rates were compared between the two groups.Results:The total treatment efficacy in the combined group was higher than that in the single group;except for operative time,the perioperative indicators in the combined group were superior to those in the single group;the Ang levels after treatment in the combined group were lower than those in the single group,and the quality of life scores were higher(P<0.05).The complication rate in the combined group was lower than that in the single group(P<0.05).Conclusion:Laparoscopy combined with choedochoscopy can enhance the treatment effectiveness for patients with difficult cholelithiasis,improve perioperative indicators,regulate their Ang levels,elevate quality of life,and demonstrate high surgical safety.
文摘Recently,the China National Intellectual Property Administration released the"List of Enterprises Approved to Use the Geographical Indication Logo."The"Wujiang Silk"geographical indication logo has been renewed and launched.This official approval serves to distinguish and celebrate the quality and cultural heritage of Shengze silk,and the use of this symbol is a testament to that distinction.Three enterprises from Shengze have been approved to use the logo:Saint Joy,Huajia Silk,and Xinmin Silk.
基金supported by the National Natural Science Foundation of China(42201339)the“Science for a Better Development of Inner Mongolia”Program of the Bureau of Science and Technology of the Inner Mongolia Autonomous Region,China(2022EEDSKJXM003)。
文摘The fine-scale characterization of vegetation surface information serves as a fundamental basis for studying the spatial distribution of resources and the dynamic patterns of environmental responses.Accurately extracting the distributions of different crop species is of critical importance for improving agricultural production efficiency and ensuring food security.Traditional fine-scale vegetation extraction methods often face significant challenges due to the presence of spectrally similar features and the substantial influence of background interference,which limit their applicability across large areas.As a key phenological stage of angiosperms,flowering is characterized by distinctive flowering times,floral morphology,and canopy spectral signatures,so it is an effective pathway for fine-scale vegetation extraction using remote sensing.Using rapeseed as an example,this study developed a spectral index model for precise flowering vegetation extraction(FI-R)based on Landsat OLI imagery.The model integrates a yellowness index(Blue,Green)and a peak index(Red,Nir and SWIR1)while leveraging the NDVI to mitigate background interference from spectrally similar objects.This approach successfully enables the rapid and accurate large-scale mapping of flowering vegetation under complex background conditions.The proposed method was tested in five rapeseed cultivation regions worldwide with diverse backgrounds.Validation datasets were generated using GF imagery and the U.S.CDL dataset.The FI-R model demonstrated superior capability in distinguishing flowering rapeseed from other vegetation,and achieved overall accuracies exceeding 94%in all study areas.Furthermore,FI-R is compatible with other multispectral sensors that have similar band configurations,so it is applicable to rapeseed extraction in broader contexts.The method also shows strong potential for the fine-scale extraction of other types of flowering angiosperm vegetation.
文摘Objective:To investigate the spatial gradient of intraoperative impedance across the cochlear electrode array in pediatric cochlear implant recipients and assess its potential as a physiological indicator for the electrode-neural interface.Methods:A prospective observational study involving 56 pediatric patients underwent cochlear implantation with Cochlear Nucleus devices.Intraoperative polarized impedance and electrically evoked compound action potential(ECAP)threshold were recorded across all 1232 electrodes using AutoNRT software.Eight electrodes with open-or short-circuit were excluded,leaving 1,224 for analysis.Impedance values were categorized by cochlear region(basal,middle,apical),and electrodes with elevated impedance(10-20 kΩ)were analyzed for regional distribution and clinical relevance.Data were analyzed for spatial patterns and correlation with the ECAP threshold profiles.Results:A consistent basal-to-apical increase in impedance was observed(7.7±1.9,9.2±1.4,10.8±1.5 kΩ;p<0.001).Impedance and ECAP threshold were weakly correlated(ρ=-0.20,p<0.001;β=-1.26,p<0.001),with a positive association in the apical region(ρ=0.12,p=0.048).Electrodes with higher impedance(1020 kΩ)were less likely to show elevated or absent TNRT(OR=0.175,p=0.02).The impedance gradient persisted across age groups and was significantly correlated with ECAP threshold patterns.Conclusion:Intraoperative impedance monitoring reveals a strong and physiologically consistent gradient,with higher values in apical electrodes.This gradient reflects anatomical and tissue interface variations,which may offer a valuable physiological indicator for intraoperative electrode positioning and neural interface integrity.
基金supported by the National Natural Science Foundation of China(NSFC)(Grant Nos.42530704 and 41427802)by the Key Project of Science and Technology Strategic Consulting of the Chinese Academy of Engineering(Grant No.2025 XZ 57).
文摘Engineering problems often involve large spatial scales and long-term lifespans.This makes it exceptionally difficult to measure engineering parameters and predict disasters such as slope instability or tunnel collapses.A key challenge is to calculate large-scale(target lifespan)quantitative indicators from small-scale(short-term)detectable results,thereby enhancing engineering safety and economic efficiency.Many engineering problems exhibit a unidirectional spatio-temporal evolution with either decay or enhancement as their spatial scale or time increases.This phenomenon is called the power law with exponential function.A general approach is required to use this evolution law in the prediction of the unknown from the known.This paper proposes a novel concept to calculate large-scale indicators via variation of small-scale data(called CLIVS for short),to address a general approach through the following five aspects:Firstly,general spatio-temporal evolution laws in engineering are systematically summarized and classified.Then,the core idea and basic concepts of CLIVS,its mathematical formulation and solution procedure are described in detail.Thirdly,the linkage of CLIVS to past famous philosophy schools is explored.Fourthly,the potential applications of CLIVS to rock mechanics and rock engineering are classified according to size effect and time-scale law.Finally,two typical examples of the application of CLIVS to engineering parameter prediction are presented.These demonstrate that the CLIVS provides a novel way and a general approach to accurately predict unknown behaviors based on known local spatial data or short-term indicators.It formulates a unified theoretical framework or universal approach to calculate unmeasurable engineering parameters or predict lifespan with reasonable accuracy from the knowns measurable at the local scale or in the short term.
基金funded by the Central University of Technology,Free State’s University Research Grants and Scholarships Committee(RGSC).
文摘Urban geochemical alteration and transformation are complex processes that affect air,water,and soil,potentially posing serious health risks to the residents.Our health is determined by where we live now,and where we have previously lived and how long we have been there.This review explores patterns of urban environmental pollution and public health risks associated with potentially harmful elements.Academic databases including Scopus,Web of Science,and Google Scholar were used to find pertinent peer-reviewed papers,reports,and case studies.It discusses urban environmental and medical geochemistry,focusing on toxic heavy metals of public health concern and their urban sources.Case studies on geochemical anomalies in street dust,atmospheric,lithochemical,and hydrochemical contexts are critically examined.The review evaluates the effectiveness of geochemical indices in assessing pollution and health risk patterns in road dust,soil,air,and water,emphasizing the importance of geochemical background in urban geochemistry and medical geology.Strategies to reduce toxic heavy metal pollution in urban areas are also reviewed to protect public health.Finally,it offers conclusions and recommendations for future research.It is obvious that the environmental geochemistry of soil,street dust,water,and air contain a wealth of information about the state of urban environments.The outcomes of this study will help to raise public awareness of urban pollution and associated health risks,promoting environmental preservation and health protection in urban settings.
基金National Natural Science Foundation of China,No.42471195,No.42022006。
文摘Securitization of economies has received much attention in urban and regional studies,as how the city economy has connected with the capital markets has been increasingly important for a city’s development.This study develops a modified Buffett indicator,calculating the ratio of total market capitalization of listed companies to the gross domestic product(GDP)of the city in which these companies are headquartered,to measure city securitization rates(CSR).Drawing on this indicator,this study maps the CSR of all prefecture-and-above level cities in China.It is found that cities with high CSR in China are mainly financial centers and some resource-based cities,while most other cities’CSR are quite low.The regression results show that city’s innovation capacity and political status are positively and significantly associated with the CSR in China.In addition,being close to financial centers can significantly improve the CSR of cities in the eastern region of the country.With the growing financialization of societies,the modified Buffett indicator has a potential to explore the city economy from the perspective of its connection with capital markets in future research.
基金support of the National Natural Science Foundation of China(Nos.52322603 and U24A20141)the Science Center for Gas Turbine Project of China(No.P2023-B-Ⅱ-001-001)the Fundamental Research Funds for the Central Universities of China and the Beijing Nova Program of China(Nos.20220484074 and 20230484479)。
文摘This study investigates the turbulence-induced disturbances and stall precursor triggering mechanism in NACA65-18(10)cascade based on large eddy simulations.The results indicate that the disturbances exist under various operating conditions along the performance curve.The shear layer is the physical structure responsible for the generation,propagation,and dissipation of disturbances.When operating near stall,the separation on the suction surface intensifies,and strong unsteady backflow occurs at the trailing edge of the passage.Under the influence of inlet disturbances,unsteady behaviors between passages form specific phase differences,leading the entire system to oscillate in a first-order mode.As the flow develops from near-stall to stall,axial momentum decreases further,reducing the main flow’s ability to drive blockages downstream through convection.Consequently,the blockage accumulates during the circumferential propagation process until the stall onset.Based on the above mechanism,this study proposes factors describing the size of the backflow zone,shedding frequency,and convection velocity to characterize blockage dynamics,identifying critical values that represent the stall onset.
文摘Agricultural Intangible Cultural Heritage(AICH)embodies collective,intergenerational knowledge sys⁃tems that are increasingly exposed to risks of misappropriation and inequitable commercialization under contemporary intellectual property(IP)regimes.This study investigates the"cost of inaction"in protecting AICH and geographical origins through a qualitative comparative case study approach,drawing on selected cases from Africa,Asia,and Latin America,alongside Chinese practices.By combining narrative analysis and thematic synthesis,the study identi⁃fies two dominant patterns:external misappropriation driven by institutional gaps-manifested in biopiracy,trademark squatting,and exploitation of information asymmetry-and internal inequities arising from commercialization processes that marginalize indigenous communities in benefit-sharing.The findings reveal that existing international IP frame⁃works,including TRIPs and the CBD,provide fragmented and insufficient protection for collective knowledge sys⁃tems.Comparative analysis of national responses highlights three distinct governance models:defensive protection(In⁃dia),rights-based sui generis legislation(Peru),and market-oriented geographical indication systems(European Union),each with inherent limitations.In contrast,Chinese practices demonstrate strong capacity in market integra⁃tion and industrial upgrading but remain constrained by weak recognition of community rights and limited institutional⁃ization of benefit-sharing mechanisms.This study contributes to the literature by proposing a composite institutional framework that integrates existing IP regimes with a sui generis system centered on collective rights recognition,prior informed consent,and mandatory benefit-sharing.The framework also emphasizes the need for embedded integration with patent,trademark,and geographical indication systems,as well as institutional adaptation in the context of the digital economy.The findings offer theoretical insights and policy implications for developing countries seeking to bal⁃ance cultural preservation,economic development,and equitable governance of traditional knowledge.
基金Supported by China Health&Medical Development Foundation,No.M2021551.
文摘BACKGROUND Inappropriate selection of patients with early gastric cancer(EGC)for endoscopic submucosal dissection(ESD)may lead to non-curative resection,necessitating additional gastrectomy.Conversely,inappropriate selection for gastrectomy may result in overtreatment,adversely affecting patients’quality of life.Few have systematically evaluated the concordance between therapeutic indications under current Japanese guidelines and pathological criteria in EGC.To minimize noncurative resection risks while sparing unnecessary surgery for low-risk patients’,we specifically assess the suitability of Japanese guidelines in non-Japanese populations.This work aims to optimize clinical practice by refining endoscopic treatment criteria for adoption beyond Japan.AIM To evaluate EGC clinical decision accuracy by comparing therapeutic indication with postoperative pathological criteria and analyzing factors influencing discrepancies.METHODS A retrospective analysis was conducted on 796 EGC cases diagnosed at Peking University Third Hospital between January 2010 and December 2022.Cases were categorized into three groups:Same-estimated(preoperative therapeutic indication with postoperative pathological criteria matched),underestimated(preoperative ESD indication but postoperative surgical criteria),and overestimated(preoperative surgical indication but postoperative ESD criteria).The rate of discrepancy and associated risk factors were assessed.RESULTS The accuracy rates of preoperative evaluation for ESD and gastrectomy indications were 73.0%(321/430)and 76.0%(278/366),respectively.The overall discrepancy rate was 25.6%(204/796).Multivariate analysis identified tumor location in the upper-third stomach(odds ratio=2.158,95%confidence interval:1.373-3.390,P=0.001)was significantly associated with a higher likelihood of being underestimated and undifferentiated histologic type on preoperative biopsy(odds ratio=2.005,95%confidence interval:1.036-3.879,P=0.039)was more likely to be overestimated.Significant differences were observed in tumor diameter(P<0.001),depth of infiltration(P<0.001),ulcerative findings(P<0.001),and histologic type(P<0.001)between preoperative and postoperative evaluations.CONCLUSION The accuracy of preoperative EGC indications is 74.4%.Upper-third stomach and undifferentiated histology are primary discrepancy predictors.Upper-third tumors are prone to underestimation,while undifferentiated tumors are prone to overestimation.
文摘The Almus Fault Zone(AFZ)is one of the major splay faults of the North Anatolian Fault Zone(NAFZ)and is important for understanding its tectonic features and assessing regional seismic hazards.This research presents the integration of morphometric indices to quantitatively assess the spatial variation of tectonic activity along the AFZ.The AFZ is an active fault with both strike-slip and normal fault components and consists of two main branches,Mercimekdağı-Çamdere Fault(MÇF)and Tokat Fault(TF)segments.This study aims to assess the relative tectonic activity of the AFZ using various morphometric indices,based on a 10 m resolution DEM,with the aid of ArcGIS and MATLAB software.For this purpose,morphometric indices such as hypsometric integral(HI:0.35-0.65),mountain front sinuosity(Smf:1.3-1.44),valley floor width-height ratio(Vf:0.15-2.28),asymmetry factor(AF:23-77),drainage basin shape(Bs:1.13-6.10)and normalized steepness index(ksn:1-498)were applied to 53 drainage basins.When the Smf and mean Vf indices results were evaluated,it was calculated that the uplift ratio of the region was more than 0.5 mm/yr.The spatial distribution of the relative tectonic activity(Iat)of the area was revealed by combining the obtained morphometric indices analysis results.According to the Iat result,it was concluded that the MercimekdağıÇamdere Fault and Tokat Fault segments have high tectonic activity,but the Mercimekdağı-Çamdere Fault segment has higher tectonic activity.The results obtained were also confirmed by field observations.This research provides valuable information for the evaluation of tectonic activity in drainage systems controlled by splay faults.
文摘Objective:To evaluate and compare coagulation and hematological parameters in hypertensive and normotensive pregnant women.Methods:This present cross-sectional study was carried out in the Departments of Pathology and Obstetrics&Gynaecology at Dr.D.Y.Patil Medical College,Hospital&Research Centre,Pimpri,Pune,India from September 2023 to March 2025.Hematological parameters[platelet count,mean platelet volume(MPV),platelet distribution width(PDW)]were analyzed using an automated hematology analyzer,while coagulation parameters[prothrombin time(PT)/international normalised ratio,activated partial thromboplastin time(aPTT),and D-dimer]were assessed by standard automated assays.Results were compared between normotensive and hypertensive groups and correlated with disease severity.Results:The study included 212 antenatal females,with 106 normotensive pregnant women and 106 hypertensive women.Hypertensive women include cases of gestational hypertension(n=55);mild preeclampsia(n=39),and severe preeclampsia(n=12).A significant progressive decrease in platelet count and significant increases in MPV,PDW,PT,aPTT,and D-dimer levels were associated with increasing severity of pregnancy-induced hypertension(P<0.001).Women with severe preeclampsia had the lowest mean platelet counts and the highest coagulation parameter values compared to women with gestational hypertension,mild preeclampsia,and normotensive pregnancies.These findings indicate enhanced platelet activation,endothelial dysfunction,and activation of the coagulation–fibrinolytic system with worsening disease severity.Conclusions:Significant hematologic and coagulation abnormalities were present in women with pregnancy-induced hypertension.For better maternal-fetal outcomes and early management,routine monitoring is essential.
文摘Diabetic kidney disease (DKD)is one of the most common and severe microvascular complications of type 2 diabetes mellitus (T2DM). It is also a major cause of end-stage renal disease (ESRD), making early identification and intervention crucial. Insulin resistance (IR)is a key pathophysiological mechanism of T2DM and plays a central role in the progression of DKD. In recent years, a series of novel surrogate indicators of IR, such as the triglyceride-glucose (TyG) index, TyG-body mass index (TyG-BMI), triglyceride to high-density lipoprotein cholesterol ratio (TG/HDL-C), and metabolic score for insulin resistance (METS-IR), have attracted widespread attention due to their simplicity and cost-effectiveness. This article reviews the research progress of novel surrogate indicators of insulin resistance (IR) in type 2 diabetic kidney disease (DKD), aiming to provide references for the early prevention and improved prognosis of DKD.
基金Funded by the National Natural Science Foundation of China(Nos.52378360,51978438)。
文摘We used solidification/stabilization methods to remediate highly concentrated Zn^(2+)-contaminated soil.An industrial waste mixture of red mud,carbide slag,and phosphogypsum is combined with cement as the curing agent.The mixing ratios of the four materials are determined by comparing the strength,permeability coefficient,pH,and Zn^(2+)-leaching concentration of the solidified soil.Microscopic characteristics of the solidified uncontaminated soil and solidified Zn^(2+)-contaminated soil were observed using scanning electron microscopy,X-ray diffraction,and Fourier-transform infrared spectroscopy.Furthermore,the heavy metals speciation in both pure cement and mixed-material solidified soil was examined,demonstrating the beneficial role of the mixed-type curing agent in stabilizing heavy metals.The research results indicate that Zn^(2+)degrade the strength of the solidified soil by up to 90%.The permeability coefficient,pH,and Zn^(2+)-leaching concentration of the solidified soil easily meet standard,especially with Zn^(2+)leaching concentration well below the environmental protection limit.Furthermore,most Zn^(2+)exists in forms with lower biological and chemical reactivity.Both the solidified Zn^(2+)-contaminated soil and uncontaminated soil resulted in the formation of hydrated products containing elements such as silicon,aluminum,calcium,and sulfur.Additionally,the solidified Zn^(2+)-contaminated soil produced zinc-containing compounds and a large amount of rod-shaped ettringite.
基金supported by the United Kingdom(UK)Darwin Initiative(28-003).
文摘The South Aral Seabed is an extreme dryland ecosystem undergoing rapid transformation yet remains misrepresented or absent in global land cover datasets.Conventional vegetation indices,specifically the Normalized Difference Vegetation Index(NDVI),perform poorly in such environments due to their limited ability to distinguish sparse vegetation from highly reflective saline and sandy soils.This study evaluated the effectiveness of the Modified Soil Adjusted Vegetation Index(MSAVI)for improving land cover classification in the South Aral Seabed and conducted a decadal analysis of land cover change between 2013 and 2023 using Landsat 8 imagery(30 m resolution).A spectral index-based classification framework was developed,combining MSAVI with the Normalized Difference Water Index(NDWI)and Salinity Index 1(SI1)to reduce spectral confusion between vegetation,saline soils,and surface water.The MSAVI-based classification achieved an overall accuracy of 77.96%(Kappa coefficient=0.71),supported by 313 field-collected validation points from 2023.While the multi-index approach enabled finer discrimination of ecologically important classes,particularly separating salt pans from solonchak soils,it resulted in a lower overall accuracy(73.80%),highlighting a trade-off between class separability and classification performance.Land cover change analysis revealed a highly dynamic landscape,with 52.96%of the study area transitioning between classes over the decade.Transformed areas(16,893 km2)exceeded stable zones(15,004 km2),driven primarily by rapid desiccation and salinization.Solonchak soils increased at an annual rate of 5.58%,while surface water bodies declined by 4.83%per year.Concurrently,sparse or distressed vegetation increased by 1.43%annually,reflecting ongoing afforestation efforts.This study provides the first MSAVI-based and medium-resolution land cover baseline for the South Aral Seabed and demonstrates that soil-adjusted vegetation indices are essential for reliable dryland classification where conventional indices fail.The proposed spectral index framework offers a replicable methodology applicable to other global drylands facing similar land degradation and restoration challenges.
