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Cost-benefit analysis of esophageal cancer endoscopic screening in high-risk areas of China 被引量:37
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作者 Juan Yang wen-Qiang wei +3 位作者 Jin Niu Zhi-Cai Liu Chun-Xia Yang You-Lin Qiao 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第20期2493-2501,共9页
AIM:To estimate the cost-benefit of endoscopic screening strategies of esophageal cancer(EC)in high-risk areas of China. METHODS:Markov model-based analyses were conducted to compare the net present values(NPVs)and th... AIM:To estimate the cost-benefit of endoscopic screening strategies of esophageal cancer(EC)in high-risk areas of China. METHODS:Markov model-based analyses were conducted to compare the net present values(NPVs)and the benefit-cost ratios(BCRs)of 12 EC endoscopic screening strategies.Strategies varied according to the targeted screening age,screening frequencies,and follow-up intervals.Model parameters were collected from population-based studies in China,published literatures,and surveillance data. RESULTS:Compared with non-screening outcomes,all strategies with hypothetical 100 000 subjects saved life years.Among five dominant strategies determined by the incremental cost-effectiveness analysis,screening once at age 50 years incurred the lowest NPV(international dollar-I$55 million)and BCR(2.52).Screening six times between 40-70 years at a 5-year interval[i.e., six times(40)f-strategy]yielded the highest NPV(I$99 million)and BCR(3.06).Compared with six times(40)fstrategy,screening thrice between 40-70 years at a 10-year interval resulted in relatively lower NPV,but the same BCR. CONCLUSION:EC endoscopic screening is cost-beneficial in high-risk areas of China.Policy-makers should consider the cost-benefit,population acceptance,and local economic status when choosing suitable screening strategies. 展开更多
关键词 Cost-benefit analysis Esophageal cancer ENDOSCOPY SCREENING high-risk area
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Reflections on the New Classification of Tumors by the WHO and Changes in Esophageal Cancer in a High-risk Area 被引量:1
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作者 Zhifeng Chen 《Chinese Journal of Clinical Oncology》 CSCD 2006年第1期61-65,共5页
ABSTRACT In year 2000, a book entitled the Pathology and Genetics of Tumors of the Digestive System was published by the WHO, presenting some new diagnostic criteria and treatment principles. I have analyzed the epide... ABSTRACT In year 2000, a book entitled the Pathology and Genetics of Tumors of the Digestive System was published by the WHO, presenting some new diagnostic criteria and treatment principles. I have analyzed the epidemiologic change of tumors in over 30 years in the high-risk area with esophageal cancer. The following phenomenon was found: accompanied by the sharp decrease in the incidence and mortality of esophageal cancer, there was an increase in the incidence and death rate of stomach cancer involving cardiac cancer. This fact should be considered when analyzing the sharp decrease in esophageal cancer incidence and mortality rate. More attention was given to diagnosis of cardiac cancer; at the same time it is more practical to improve the early screening of cancers. To observe the development of high and low - grade intraepithelial neoplasms will be an urgent task for esophageal cancer research in the high risk area, according to WHO's new classification. 展开更多
关键词 WHO tumor new classification epidemiology esophageal cancer the high-risk area.
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Geographical Indication Protection and Regional Public Brand Development of Traditional Chinese Medicine Herbs in Wuling Mountain Area 被引量:1
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作者 Yuanpeng SUN Fei QU +4 位作者 Yanping ZHANG Jianda SUN Pei SUN Zhiyang YUAN Zhiguo SUN 《Asian Agricultural Research》 2026年第2期1-11,26,共12页
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
关键词 Agricultural intellectual property Geographical indication(GI) Regional public brand Chinese medicinal materials Wuling Mountain area
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Pollution Characteristics and Sources of Heavy Metal in the Soil Around a Concentrated Lead and Zinc Mining Area in Guangxi
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作者 LU Yuqiu TANG Xiaohui +5 位作者 XIN Meifen HUANG Yanhong LI Yang WU Hao LUO Dongyuan ZHOU Lang 《有色金属(中英文)》 北大核心 2026年第2期392-411,共20页
39 soil samples surrounding a lead-zinc mining area in Guangxi were collected,and the contents of Pb,Hg,Cd,Cr,As,Cu,Zn,and Ni were determined to investigate the pollution characteristics and sources of heavy metals.Ar... 39 soil samples surrounding a lead-zinc mining area in Guangxi were collected,and the contents of Pb,Hg,Cd,Cr,As,Cu,Zn,and Ni were determined to investigate the pollution characteristics and sources of heavy metals.ArcGIS inverse distance weight difference method was used to analyze the characteristics of pollution distribution,and single-factor pollution index,Nemerow comprehensive pollution index,ground accumulation index,and potential ecological risk index were selected to evaluate the characteristics of heavy metal pollution.Based on correlation analysis,the absolute principal component-multiple linear regression(APCS-MLR)and positive definite matrix factorization(PMF)models were used to analyze the sources of soil heavy metals.The results showed that the average concentrations of all eight heavy metals exceeded both national and Guangxi soil background values.Hg,Cd,and Zn exhibited high variation(greater than 0.5),indicating significant external disturbances,and their spatial distribution was closely related to mining activity locations.The single-factor pollution index evaluation indicated varying degrees of pollution risk for Cd,Zn,and As,with Cd and Zn being the most severe pollutants,as 69.23%and 30.77%of the samples fell into the moderate pollution or higher category.The geoaccumulation index analysis ranked the mean pollution levels of the eight elements as follows:Zn>Cd>Ni>Pb>Cu>Cr>Hg>As,with Cd and Zn showing the most severe contamination,and 51.28%of the samples exhibiting moderate or higher pollution levels.The Nemerow comprehensive pollution index evaluation showed that 74.35%of soil samples were classified as moderate to heavy pollution.The potential ecological risk index assessment indicated significant ecological risks posed by Cd and Zn,with 82.05%and 5.12%of the samples classified as causing strong to extreme ecological risks,respectively.The source apportionment analysis revealed minor differences between the two models.The APCS-MLR model identified three pollution sources and their contribution rates:anthropogenic mining sources(31.13%),parent material sources(40.38%),and unidentified sources(28.49%).The PMF model identified three pollution sources with contribution rates of anthropogenic mining sources(26.10%),parent material sources(46.96%),and a combined traffic and agricultural source(26.61%).Pb,Hg,Cd,and Zn mainly originated from mining activities;Cr,As,and Ni were primarily derived from the parent material,while Cu was predominantly attributed to traffic and agricultural sources.These findings provide a scientific basis for the prevention and control of heavy metal pollution in mining areas. 展开更多
关键词 mining area soil heavy metals pollution characteristics risk assessment source apportionment
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Development of the Framework for Traffic Accident Visualization Analysis (F-TAVA) Based on the Conceptualization of High-Risk Situations in Autonomous Vehicles
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作者 Heesoo Kim Minwook Kim +2 位作者 Hyorim Han Soongbong Lee Tai-jin Song 《Computers, Materials & Continua》 2026年第5期856-880,共25页
Autonomous vehicles operate without direct human intervention,which introduces safety risks that differ from those of conventional vehicles.Although many studies have examined safety issues related to autonomous drivi... Autonomous vehicles operate without direct human intervention,which introduces safety risks that differ from those of conventional vehicles.Although many studies have examined safety issues related to autonomous driving,high-risk situations have often been defined using single indicators,making it difficult to capture the complex and evolving nature of accident risk.To address this limitation,this study proposes a structured framework for defining and analyzing high-risk situations throughout the traffic accident process.High-risk situations are described using three complementary indicators:accident likelihood,accident severity,and accident duration.These indicators explain how risk emerges,increases,and persists over time.Based on this concept,a framework for traffic accident visualization analysis is developed to support phase-specific risk assessment and visualization.The framework combines accident-phase information with factor-level risk contributions,allowing systematic identification of key factors and their interactions across different accident stages.Using combinations of the three indicators,high-risk situations are classified into twenty-seven distinct types,providing a clear typology for complex accident scenarios involving autonomous vehicles.The applicability of the proposed framework is demonstrated through two representative accident scenarioswith different risk characteristics.The results showthat the framework effectively captures interactions among multiple risk factors,explains how risk levels change from pre-crash to post-crash phases,and identifies contributing factors that are difficult to detect using conventional traffic accident investigation methods.Overall,the proposed framework offers a practical basis for autonomous vehicle accident analysis,safety evaluation,and policy-related decision-making. 展开更多
关键词 Autonomous vehicle high-risk situations traffic accident traffic safety
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The Impact of Mother-Infant Separation on the Physical and Mental Health of Women with High-Risk Pregnancies and Corresponding Nursing Strategies
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作者 Qing Yang 《Journal of Clinical and Nursing Research》 2026年第1期145-152,共8页
Objective:To analyze the impact of maternal-infant separation on the physical and mental state of high-risk pregnancy patients and explore the clinical efficacy of targeted nursing interventions.Methods:A total of 80 ... Objective:To analyze the impact of maternal-infant separation on the physical and mental state of high-risk pregnancy patients and explore the clinical efficacy of targeted nursing interventions.Methods:A total of 80 high-risk pregnancy patients treated in our hospital from January 2023 to January 2024 were selected as the study subjects.These patients were randomly divided into an observation group and a control group(40 cases each)using a random number table.The control group received routine high-risk pregnancy nursing care,while the observation group received specialized maternal-infant separation nursing interventions in addition to routine care.The psychological and physiological states and nursing satisfaction of the two groups were compared before and after the intervention.Results:The SAS scores,SDS scores,and sleep quality scores of the observation group were significantly lower than those of the control group,with statistically significant differences(p<0.05).The incidence of postpartum hemorrhage in the observation group was significantly lower than that in the control group,and the initiation time of lactation was significantly earlier than that in the control group,with both differences being statistically significant(p<0.05).The nursing satisfaction of the observation group was significantly higher than that of the control group(80%vs.32/40),with a statistically significant difference(p<0.05).Conclusion:Maternal-infant separation exacerbates anxiety and depression in high-risk pregnancy patients,reduces sleep quality,increases the risk of postpartum hemorrhage,and delays the initiation of lactation.Specialized nursing interventions for maternal-infant separation can improve the physical and mental state of high-risk pregnancy patients,reduce the incidence of postpartum complications,and enhance nursing satisfaction,making them worthy of clinical application and promotion. 展开更多
关键词 Mother-infant separation high-risk pregnancy women Physical and mental health Nursing strategies
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Application of Cytokines in Cervical Secretion for High-grade Squamous Intraepithelial Lesion Caused by High-risk Human Papillomavirus Infection
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作者 Lingyun Ji Xiao Wang +7 位作者 Ruixian Jiao Ji Yang Jiaqi Han Bowen Xu Yang Zhou Jing Wu Xiaowen Pu Wenhong Zhang 《Biomedical and Environmental Sciences》 2026年第2期215-222,共8页
Objective The aim of this study was to analyze the correlation between the levels of 12 cytokines in the cervical microenvironment and cervical intraepithelial neoplasia in patients with high-risk human papillomavirus... Objective The aim of this study was to analyze the correlation between the levels of 12 cytokines in the cervical microenvironment and cervical intraepithelial neoplasia in patients with high-risk human papillomavirus(HR-HPV)infection.Methods Female patients(n=73)with HR-HPV infection were enrolled and divided into a high-grade squamous intraepithelial lesion(HSIL)group(n=33)and a non-HSIL(N-HSIL)group(n=40),which include low-grade squamous intraepithelial lesions and inflammation.Healthy screening subjects(n=31)with negative HR-HPV results were enrolled as a control group.We examined contemporaneous plasma and secretory cytokines from 25 study subjects to investigate the difference between systemic cytokine profiles and the local microenvironment immunity using the Wilcoxon matched-pairs signed rank test.The 12 cytokines from cervical secretions were compared between the three groups using the Mann-Whitney test,and logistic regression was used to analyze HSIL and N-HSIL.Results There were statistical differences in eight cytokines(IL-2,IL-6,TNF-α,IFN-γ,IL-1β,IL-12p70,IFN-α,and IL-8)between cervical secretion and plasma of the same patient,and seven cytokines were statistically different between the control and other two groups.We selected four independent variables(TNF-α,IFN-γ,IL-12p70,and IFN-α)commonly identified by univariate regression analysis and non-parametric tests for multivariate logistic regression analysis.Based on this model,HSIL could be predicted in patients with HR-HPV infection,with the area under the curve being 0.76.Conclusion The systemic cytokine profile cannot reflect the local microenvironment immunity,and the occurrence of HSIL is related to the cytokine levels in the cervical microenvironment. 展开更多
关键词 high-risk human papillomavirus CYTOKINES High-grade squamous intraepithelial lesion
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Prenatal exposure to bisphenols,metals,and risk of fetal chromosome numerical abnormalities in high-risk pregnancies:Independent,combined,and interactive effects
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作者 Jinglin Li Mengli Yang +8 位作者 Jingting Chen Dan Wang Hongyue Sun Zinuo Wang Xiaoyu Li Ying Chang Baoqin Huang Xi Chen Nai-jun Tang 《Journal of Environmental Sciences》 2026年第2期51-59,共9页
Prenatal exposure to bisphenols and metals has raised significant concerns regarding their potential impact on fetal development,particularly the risk of fetal chromosome numerical abnormalities(CNA).In this case-cont... Prenatal exposure to bisphenols and metals has raised significant concerns regarding their potential impact on fetal development,particularly the risk of fetal chromosome numerical abnormalities(CNA).In this case-control study,we analyzed bisphenol and metal concentrations in amniotic fluid of high-risk pregnant women undergoing amniocentesis.Concentrations of bisphenols and metals were measured using ultra-performance liquid chromatography-tandem mass spectrometry and inductively coupled plasma-mass spectrometry,respectively.Logistic regression and quantile-based g-computation were applied to evaluate individual and combined effects,while dose-response relationships were assessed using restricted cubic splines.Our findings indicated that bisphenol S(BPS),bisphenol Z(BPZ),bisphenol AF(BPAF),antimony(Sb),and vanadium(V)were significantly associated with an increased risk of CNA when analyzed individually,whereas manganese,iron,copper(Cu),nickel(Ni),and zinc(Zn)were significantly and inversely associated with CNA risk.Combined exposure to bisphenol and metal mixtures was associated with an increased risk of CNA in multi-pollutant models.Cu and Ni exhibited a positive additive interaction.Furthermore,BPS,BPZ,and BPAF were individually associated with an increased risk of Down syndrome,while Zn was associated with a decreased risk of Down syndrome.BPS,Sb,V,and Zn were individually associated with an increased risk of Klinefelter syndrome.These findings underscore the potential role of prenatal bisphenol and metal exposure in the pathogenesis of fetal CNA,highlighting both additive and synergistic effects. 展开更多
关键词 BISPHENOL Metal Chromosome numerical abnormalities high-risk pregnant women Down syndrome Klinefelter syndrome
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Strategies and Policies for Developing Rural “Local Specialty Products” in Ecological Conservation Areas
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作者 Wei Houkai Hu Lingxiao 《Contemporary Social Sciences》 2026年第1期90-103,共14页
The promotion of rural revitalization within the ecological conservation areas(“ECAs”) requires a careful balance between ecological protection and economic development and should be guided by the principle of ecolo... The promotion of rural revitalization within the ecological conservation areas(“ECAs”) requires a careful balance between ecological protection and economic development and should be guided by the principle of ecological priority. The cultivation of rural “Local Specialty Products”(“LSPs”) under a green-development framework aligns with the functional positioning of these areas, drives the revitalization of rural industries, and constitutes a fundamental strategy for addressing the unique challenges they face. Although ECAs possess inherent advantages in terms of developing LSPs, they are also confronted by multiple constraints. Accordingly, we propose development objectives that emphasize(a) driving rural industrial prosperity,(b) enhancing the appeal of agricultural heritage, and(c) ensuring inclusive prosperity in the farming communities. In selecting pathways for growth, priority should be given to improving the quality of products, fostering distinctiveness of the technologies, nurturing cultural identities, and upholding the principle of common prosperity. From a policy standpoint, the development of rural LSPs should be recognized as a key lever for advancing the comprehensiveness of rural revitalization in the ECAs. We recommend a set of supportive measures—namely, reinforcing the guidance for spatial planning, integrating the consolidation of factor inputs, and ensuring the robustness of organizational guarantees—to facilitate the high-quality development of LSPs in these areas. 展开更多
关键词 ecological conservation areas areas rural local specialty products(LSPs) development objectives PATHWAYS policy support
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Investigating the Mental Health of Left-Behind Children in China’s Rural Areas:A Systematic Review Approach
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作者 Jian Li Yide Chen +1 位作者 Xinyi Zhao Eryong Xue 《International Journal of Mental Health Promotion》 2026年第3期1-25,共25页
Background:The mobility of people in rural areas may lead to more and more left-behind children(LBC)appearing,and being an LBC brings a lot of risks to mental health,which could greatly hinder children’s development ... Background:The mobility of people in rural areas may lead to more and more left-behind children(LBC)appearing,and being an LBC brings a lot of risks to mental health,which could greatly hinder children’s development and undermine their happiness and safety in life.Previous scholars have conducted plenty of studies that focused on Chinese rural LBCs’mental health issues,such as what they exactly look like and some potential factors,but there remains a paucity of reviews about the relationship among certain mental health issues.We will try to figure out how the most common mental health issues of LBC in China’s rural areas correlate with each other,as well as their related factors.Methods:In this study,we used a systematic review approach to analyze 35 publications from Web of Science and EBSCO(to August 2025),followed by the sorting standards of Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)2020.Results:By mainly using quantitative techniques,we found that Chinese rural LBC are more likely to have mental health issues than children who have no experience of being left behind,and they often suffer from depression,social anxiety,internet addiction,and suicidal ideation.These four mental health issues share influencing factors and positively correlate with each other.We also found that Chinese rural LBCs are somewhat resilient towards the risk factors of mental health issues,and national or social policies and interventions can really help them a lot.Conclusion:For Chinese rural LBC,there are important relationships among the common psychological disorders they often suffer,along with multiple factors that affect their mental health,which can help related scholars and practitioners pay attention to such mechanisms and think more comprehensively when they try to help the children who are left behind. 展开更多
关键词 Left-behind children rural area China mental health systematic review
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Adaptation needs and adaptation options vary among different stakeholders in high-latitude protected areas: A case study of the Qiangtang Protected Area in China
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作者 Jianguo Wu Mengdi Fu 《Chinese Journal of Population,Resources and Environment》 2026年第1期110-128,共19页
It is essential to understand how adaptation needs and options differ among stakeholders in protected areas(PAs)to effectively implement climate change(CC)adaptation strategies.Using the Qiangtang PA in Xizang as a ca... It is essential to understand how adaptation needs and options differ among stakeholders in protected areas(PAs)to effectively implement climate change(CC)adaptation strategies.Using the Qiangtang PA in Xizang as a case study,this research examines CC adaptation needs and options from the perspectives of stakeholders across multiple administrative levels,including provincial,prefectural,county authorities,73 protection stations,and 13364 pastoralists residing within the PA.The findings show that stakeholders at the provincial level,as well as those from the Ali and Naqu prefectures and six counties,place greater emphasis on institutional and resource-related needs than on other categories(attention score:7.0-9.3 vs.5.0-7.0).In contrast,stakeholders from the 73 protection stations prioritize technological and capacity-building needs more strongly than other types(attention score:8.0-9.0 vs.4.0-8.0).The 13364 pastoralists assign the highest importance to social needs relative to other categories(attention score:9.0-9.5 vs.3.0-8.0).Most of the eight existing protection measures were found to indirectly support broader climate adaptation efforts.In particular,protective actions addressing fire,pests,and weather-related disasters can be classified as autonomous adaptation,while other measures generate outcomes that enhance adaptation capacity under specific conditions.Adaptation options,grouped into three main types and 13 subcategories,differ across stakeholder groups,although substantial overlap exists between these options and current protective actions,including ecosystem based adaptation strategies,adaptation-related practices,autonomous adaptation measures,and emergency interventions.Overall,these findings highlight the critical role of all stakeholders-especially staff from the 73 protection stations and the 13364 pastoralists-in the effective implementation of adaptation actions within the PA. 展开更多
关键词 Climate change Biodiversity conservation Protected area Adaptation needs Adaptation options
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Petrogenesis of Permian-Triassic Sanukites in the Funing Area,South China:Insights into Backarc Basin Magmatism Driven by Paleo-Tethys Plate Subduction
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作者 LI Zhenglin LIU Xijun +4 位作者 SONG Yujia ZHAO Bing LIU Lei YU Hongxia SHI Yu 《Acta Geologica Sinica(English Edition)》 2026年第1期121-136,共16页
High-Mg andesites(HMAs)typically originate in subduction-related tectonic settings,including active continental margins and island arcs,and studies of HMAs can constrain the tectonic evolution of the South China Block... High-Mg andesites(HMAs)typically originate in subduction-related tectonic settings,including active continental margins and island arcs,and studies of HMAs can constrain the tectonic evolution of the South China Block and Paleo-Tethyan Ocean.This paper presents new chronological and geochemical data for high-Mg gabbroic diorites in the Funing area,southern South China.The gabbroic diorites yield ages of 254-249 Ma,and have moderate SiO2 contents(51.3%-57.8%),high MgO contents(4.6%-10.2%)and Mg^(#)values(52-75),enrichment in large-ion lithophile elements and light rare earth elements,and depletion in high-field-strength elements-collectively displaying geochemical signatures typical of sanukites.The gabbroic diorites have radiogenic initial Sr and Pb isotopic compositions,and negativeεNd(t)andεHf(t)values.These characteristics distinguish the Funing gabbroic diorites from subduction-related igneous rocks in the Paleo-Pacific tectonic domain.Instead,they are isotopically similar to HMAs and basalts along the Paleo-Tethys suture.We propose the high-Mg gabbroic diorites and basaltic andesites in Funing area share a common mantle source,linked to subduction and rollback of the Paleo-Tethyan plate beneath the South China Block,which triggered back-arc rifting and partial melting of the metasomatized lithospheric mantle during the Late Permian to Early Triassic. 展开更多
关键词 high-Mg gabbroic diorite Funing area southern South China Paleo-Tethys Plate
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Collaborative Area Coverage Method for UAV Swarm Under Complex Boundary Conditions:A Region Partitioning Approach
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作者 Jiabin Yu Haocun Wang +4 位作者 Bingyi Wang Yang Lu Xin Zhang Qian Sun Zhiyao Zhao 《Journal of Bionic Engineering》 2026年第1期524-548,共25页
Unmanned aerial vehicles(UAVs)are widely utilized in area coverage tasks due to their flexibility and efficiency in geo-graphic information acquisition.However,complex boundary conditions in actual water area maps oft... Unmanned aerial vehicles(UAVs)are widely utilized in area coverage tasks due to their flexibility and efficiency in geo-graphic information acquisition.However,complex boundary conditions in actual water area maps often reduce coverage efficiency.To address this issue,this paper proposes a map preprocessing algorithm that linearizes boundary lines and processes concave areas into concave polygons,followed by gridding the map.Additionally,a collaborative area coverage method for UAV swarms is introduced based on region partitioning,which considers the comprehensive cost of energy consumption and time.An improved Hungarian algorithm is utilized for region partitioning,and a Dubins-A*-based plow-ing area full coverage path planning method is proposed to achieve path smoothing and collaborative coverage of each partition.Two sets of simulation experiments are conducted.The first experiment verifies the effectiveness of the map preprocessing algorithm,and the second compares the proposed collaborative area coverage algorithm with other methods,demonstrating its performance advantages. 展开更多
关键词 Complex boundaries UAV swarm Collaborative area coverage Map preprocessing Region partitioning
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Control Effect of the Paleomarine Environment on Gas Hydrate Reservoir Since the Pleistocene in the Dongsha Area,Northern South China Sea
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作者 XU Hongyuan BAI Chenyang +3 位作者 CHEN Wenlin XU Xiaolei WANG Yuhan WANG Hongbin 《Acta Geologica Sinica(English Edition)》 2026年第1期200-219,共20页
The Dongsha area,a key target for gas hydrate exploration,is influenced by multiple factors,including sedimentary processes and the paleoenvironment,which play critical roles in gas hydrate formation.To elucidate the ... The Dongsha area,a key target for gas hydrate exploration,is influenced by multiple factors,including sedimentary processes and the paleoenvironment,which play critical roles in gas hydrate formation.To elucidate the coupling among sedimentary processes,paleoenvironment,and gas hydrate accumulation,this study investigates the Site DS-W16 using particle size analysis,biological component content,and geochemistry data.Oxygen isotope data from foraminifera and biostratigraphic evidence indicate that sedimentation at the bottom of core interval from Site DS-W16 began during MIS 11(Marine isotope stage).The sedimentation dynamics of the studied layers are complex,involving gravity flows,traction currents,and suspended deposition.Organic matter shows a significant correlation with transgressive-regressive cycle.The site DS-W16 contains two distinct gas hydrate reservoirs:a shallow reservoir(10-24 mbsf)and a deep reservoir(below 182 mbsf).The paleomarine environment influences gas hydrate accumulation by altering sedimentary processes and sediment characteristics,especially the distribution of biological components.Both shallow and deep gas hydrate reservoirs formed under dynamic conditions dominated by traction currents and are characterized by a higher abundance of foraminifera.Sedimentary layers rich in foraminifera and modified by traction currents represent key intervals for preferential gas hydrate accumulation. 展开更多
关键词 gas hydrate accumulation PALEOENVIRONMENT sedimentary process organic matter FORAMINIFERA Dongsha area
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Assessing spatial equity in employment opportunities in low-rent residential areas: Evidence from Urumqi,China
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作者 FAN Liqin LEI Jun +1 位作者 ZHANG Shubao DUAN Zuliang 《Regional Sustainability》 2026年第2期95-115,共21页
Differentiation in housing costs reinforces the concentration of low-income groups in lowrent residential areas through residential location sorting,making the surrounding employment opportunity environment a crucial ... Differentiation in housing costs reinforces the concentration of low-income groups in lowrent residential areas through residential location sorting,making the surrounding employment opportunity environment a crucial perspective for assessing urban inclusiveness.Using residential areas as the unit of analysis,this study proposed a multidimensional framework for evaluating the spatial equity of urban employment by jointly capturing disparities between opportunity supply and access across three dimensions: employment opportunity quantity,wage levels,and commuting accessibility.In addition,we compared spatial differentiation among residential area types under rentbased stratification.This study focused on Urumqi,a major city in Northwest China,and integrated multisource geospatial data for 3465 residential areas,including points of interest(POIs),online job postings,and rental data for residential areas.Empirical analyses were conducted using the Gini coefficient,location quotient,and Geographically Weighted Regression(GWR) model.The findings reveal marked disparities in employment access across ring road areas and rent-based groups.In the urban core,low-rent residential areas benefit from relatively favorable commuting conditions;however,the accessible employment opportunities are concentrated in low-wage service sectors.In the peripheral zone,low-rent residential areas face a dual disadvantage of limited nearby employment supply and longer commuting distances.Even when spatial conditions are comparable,low-rent residential areas are systematically disadvantaged relative to non-low-rent residential areas in realized access to both employment opportunity quantity and wage levels.This pattern indicated that capability constraints impede the conversion of spatial resources into effective access.Further analyses highlight housing costs,infrastructure quality,and residential location as key associated factors.The findings underscored the importance of coordinated,targeted policies in affordable housing delivery,the spatial distribution of employment opportunities,and improvements in transport accessibility to promote urban spatial justice. 展开更多
关键词 Housing costs Spatial equity Low-rent residential areas Employment opportunities Capability constraints
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Multi-Area Path Planning for Multiple Unmanned Surface Vessels
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作者 Jianing Wu Yufeng Chen +2 位作者 Li Yin Huajun He Panshuan Jin 《Computers, Materials & Continua》 2026年第4期1093-1110,共18页
To conduct marine surveys,multiple unmanned surface vessels(Multi-USV)with different capabilities perform collaborative mapping in multiple designated areas.This paper proposes a task allocation algorithm based on int... To conduct marine surveys,multiple unmanned surface vessels(Multi-USV)with different capabilities perform collaborative mapping in multiple designated areas.This paper proposes a task allocation algorithm based on integer linear programming(ILP)with flow balance constraints,ensuring the fair and efficient distribution of sub-areas among USVs and maintaining strong connectivity of assigned regions.In the established gridmap,a search-based path planning algorithm is performed on the sub-areas according to the allocation scheme.It uses the greedy algorithm and the A*algorithm to achieve complete coverage of the barrier-free area and obtain an efficient trajectory of each USV.The greedy algorithm enables fast local traversal of unvisited grids,while the A*algorithm ensures navigation to escape from deadlock areas and maintains global path continuity.The comparison of task allocation results proves that the task allocation algorithm based on ILP improves the mapping efficiency and task distribution fairness.The proposed allocation method and result analysis provide a certain reference for the practical application ofMulti-USV to perform survey tasks collaboratively. 展开更多
关键词 Multiple unmanned surface vessels multiple areas integer linear programming
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Conservation priority for protected areas in Fuzhou,southeast China:An integrated inside-out approach based on ecological network
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作者 CAI Xinyu XU Zesong +2 位作者 YOU Weibin KATTEL Giri WANG Yingzi 《Journal of Mountain Science》 2026年第1期327-342,共16页
Addressing the widespread issues of internal fragmentation within protected areas and the neglect of surrounding critical habitat networks,this study aims to develop an assessment framework for the precise identificat... Addressing the widespread issues of internal fragmentation within protected areas and the neglect of surrounding critical habitat networks,this study aims to develop an assessment framework for the precise identification and remediation of regional conservation gaps.To this end,we introduce the Framework for Conservation Priority Identification(FCPI).The framework integrates Morphological Spatial Pattern Analysis(MSPA),the Remote Sensing Ecological Index(RSEI),Circuit Theory,and the Minimum Cumulative Resistance(MCR)model to formulate a multidimensional conservation priority index.This index facilitates the identification of critical ecological network components and enables the dynamic prioritization of conservation efforts.A case study of Fuzhou City from 2014 to 2020 reveals that despite an overall improvement in regional environmental quality,the functionality of core ecological sources has markedly declined.Between 2014 and 2020,the number of ecological sources grew by 76.9%,yet their total area shrank by 13.9%.Concurrently,the number of ecological corridors rose from 27 to 53,extending their total length by 380.23 km,which indicates an intensifying trend of habitat fragmentation.Furthermore,a significant number of crucial ecological network nodes,particularly within Minhou County,lie explicitly outside the existing protected area system.This confirms the presence of conservation gaps and unveils the spatiotemporal dynamics of shifting conservation priorities.The research validates that the proposed FCPI can effectively diagnose the dynamic deficiencies within conservation systems.It offers scientific decisionsupport for local governments,facilitating a transition from isolated conservation efforts towards systematic and comprehensive ecological network governance. 展开更多
关键词 Conservation prioritization Ecological corridors Protected areas Remote sensing ecological index Landscape connectivity
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Leaf adaptation-based competition strategy drives litter carbon accumulation during understory species replacement in plantations of karst areas
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作者 Jin Tan Shufang Li +6 位作者 Luqi Wang Lei Wang Qingsong Duan Bin Ou Fan Zhang Ledan Cao Zhangyun Li 《Journal of Forestry Research》 2026年第2期100-115,共16页
The establishment of plantations has become a critical approach for reducing greenhouse gas emissions,particularly in fragile environments with carbon sequestration potential.In karst areas,plantations based on fastgr... The establishment of plantations has become a critical approach for reducing greenhouse gas emissions,particularly in fragile environments with carbon sequestration potential.In karst areas,plantations based on fastgrowing afforestation species made significant contributions to enhancing carbon sequestration.However,the impact of understory vegetation on carbon accumulation remains unclear.Especially,the carbon accumulation associated with litter produced during the replacement of understory species receives insufficient attention,which leads to the neglect of the carbon sequestration potential in plantations of karst areas.Leaf is a crucial organ that links the litter production.To explore how leaf traits adapt to competitive environments and drive litter carbon accumulation during understory species replacement,this study observed leaf traits and litter carbon content changes in three types of plantations in the Liujiang River Basin,a typical karst area.A total of 37 sampling plots were selected for field investigation over a twoyear period.Leaf traits,species diversity,vegetation coverage,and litter carbon characteristics in understory vegetation were measured.Variance analysis,allometric equations,and path analysis were used for data analysis.The results showed that most understory species adopted a biomass conservation strategy under high-coverage conditions(>44.27%)and expanded competitive leaf area under low-coverage conditions(<44.27%).However,Bidens pilosa and Miscanthus floridulus exhibited strong competitiveness during understory species replacement.They showed an expansion of competitive leaf area under high-coverage conditions.This competitive strategy reduced species diversity and community specific leaf area.But the rapid expansion of Bidens pilosa and Miscanthus floridulus increased understory vegetation coverage,and their increased specific leaf area facilitated leaf shedding,resulting in significant litter weight accumulation(P<0.05),thereby enhancing litter carbon content per unit area.These competitive strategies were key driving factors for the increase in litter carbon content per square meter,which reached a maximum of 49.6% higher than that in natural grasslands.And the maximum increase in litter carbon accumulation derived from understory vegetation reached 3.37 times from 2023 to 2024 in plantations.In the understory vegetation of plantations,the competitive strategies reflected by leaf adaptation of key competitive species are critical factors influencing litter carbon accumulation.Future research could deeply explore the carbon sequestration effects resulting from the dynamic changes in competition within the understory vegetation of plantations. 展开更多
关键词 Allometric relationship Specific leaf area Slope direction Understory vegetation coverage Carbon accumulation
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Predicting potential suitable areas of Orchidaceae plants with national key reserve from Heilongjiang province in MaxEnt models
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作者 Weixue Zhong Xiaoxue Wei +6 位作者 Yujia Yu Xiaoqing Tang Ye Zhang Xinyu Huang Xiaohui Li Ying Liu Dewen Li 《Ecological Frontiers》 2026年第1期18-28,共11页
The study aimed at predicting potential suitable areas with national key reserve Orchidaceae plants in Heilongjiang province and conducive to plant protection.The distribution point data of six Orchidaceae plants and ... The study aimed at predicting potential suitable areas with national key reserve Orchidaceae plants in Heilongjiang province and conducive to plant protection.The distribution point data of six Orchidaceae plants and 19 bioclimatic variables were selected,and the environmental factors required for modeling were screened out by pearson correlation analysis and variance inflation factor(VIF)analysis.The potential suitable areas of Orchidaceae plants were predictat present and under different climate scenarios in 2090s by using geographic information system(GIS)and Maximum Entropy Model(MaxEnt).And then evaluated the prediction accuracy of the MaxEnt model using the AUC value,the TSS value and the Kappa value.The results showed that:1)The area under curve(AUC)values,true skill statistics(TSS)values and KAPPA values predicted by MaxEnt model were separately above 0.9,0.85 and 0.75.2)Under the climate scenario at present,the total suitable area of Orchidaceae plants was about 9.61×10^(6)km^(2),which was mainly distributed in Heilongjiang province.Among them,the high-suitable area of Cypripedium shanxiense S.C.Chen was the largest,the non-suitable area of Cypripedium guttatum Sw was the largest.3)Under different climate scenarios in 2090s,the total suitable area was slightly increasing(9.62×10^(6)km^(2)).Among them,Cypripedium shanxiense S.C.Chen and Gastrodiae Rhizoma both showed the trend of expansion to the southwest,China,and the suitable areas expanded significantly.Comprehensive factor analysis showed that temperature and precipitation were the main bioclimatic variables of suitable areas distribution,and the low emission scenario(SSP 2-4.5)will be more conducive to the survival of Orchidaceae plants. 展开更多
关键词 Orchidaceae plants Potential suitable areas Bioclimatic variables MaxEnt models National key reserve
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Effect of surface area and pore size on long-term bone regeneration:dynamic changes in geometric characteristics,mass transport,and mechanobiology
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作者 Xing Peng Guoxian Zhang +5 位作者 Jian Pu Shu Yang Wen Cui Xue Zhou Shuxin Qu Zhongmin Jin 《Bio-Design and Manufacturing》 2026年第1期137-152,I0021,共17页
The specific surface area(S S)and pore size(D)exhibit an inherent trade-off in the microscale design of bone implants:larger pores typically correlate with reduced surface area and vice versa.This relationship has att... The specific surface area(S S)and pore size(D)exhibit an inherent trade-off in the microscale design of bone implants:larger pores typically correlate with reduced surface area and vice versa.This relationship has attracted notable attention because of its critical role in the regulation of cell adhesion and osteogenesis.However,it remains largely unclear how S S and D affect the generated bone tissue and dynamically change during long-term osteogenesis.Herein,by applying rigorous geometric mapping to minimal surfaces,we constructed precisely partitioned and layer-by-layer thickened tissue models to simulate osteogenesis across different temporal scales and thereby track the dynamic evolution of geometric characteristics,permeability,and mechanobiological tissue differentiation.The high-S S samples were found to facilitate the rapid formation of new bone tissue in the early stages.However,their smaller pores tended to cause occlusions,hindering further tissue development.In contrast,low-S S samples showed slower bone regeneration,but their larger pores provided adequate physical space for tissue regeneration and mass transport,ultimately promoting bone formation in the long term.Mechanobiological regulation suggests that fibrous tissue formation inhibits additional bone formation,establishing a dynamic equilibrium between osteogenesis and pore space to sustain nutrient/waste exchange throughout the regenerative process.Overall,smaller pores are preferable in implants for minimally loaded osteoplasty procedures focused on early-stage bone consolidation,whereas larger pores are preferable in dynamically loaded implants requiring prolonged mechanical stability. 展开更多
关键词 Minimal surface Specific surface area Pore size Bone ingrowth MECHANOBIOLOGY Finite element simulation
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