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1990~2016年湘江流域水质时空变化及驱动因素分析

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环境科学 2024年第7期45卷 3953-3964页

作者：毛德华周滢周懿琳湖南师范大学地理科学学院长沙410081 洞庭湖流域生态环境变化与固碳增汇湖南省重点实验室长沙410081

为探讨湘江全流域水质时空变化特征及其驱动机制,收集湘江流域1990~2016年共26年113个站点16个水质参数数据,采用水质指数法等对流域水质进行综合评价并识别其主要污染物,分析其形成机制,重点剖析水位和土地利用格局对水质的驱动作用.... 详细信息

为探讨湘江全流域水质时空变化特征及其驱动机制,收集湘江流域1990~2016年共26年113个站点16个水质参数数据,采用水质指数法等对流域水质进行综合评价并识别其主要污染物,分析其形成机制,重点剖析水位和土地利用格局对水质的驱动作用.结果表明:(1)研究期间湘江流域整体水质等级为“良好”.时间上,水质呈现出先恶化再改善的变化态势,1990~2003年为水质恶化阶段,2004~2016年为水质改善阶段;水质季节变化不明显,丰水期水质波动较大.空间上,干流水质污染负荷从中游、下游和上游依次减小.上游支流水质最好,水质较差区域主要分布在中下游支流河口处,尤其是有多条支流汇流的地方.(2)有毒重金属具有毒性、持续性和生物累积性的特点,在水体中若超过一定浓度就难以净化,对自然环境和人类健康都危害极大.毒性金属指标(CI1)是影响湘江水质的主导因素,其中汞(Hg)和镉(Cd)是影响湘江流域整体水质的主要参数.(3)水位通过稀释环境参数对湘江水质产生正面影响,土地类型对重金属浓度影响不大,林地可以起到改善水质的作用,草地在较大尺度范围(≥5 km)与高锰酸盐指数存在负相关,流域内水体、耕地和不透水面面积的增加使得水体粪大肠菌浓度偏高的概率增加.(4)土地利用方式对水质的解释能力呈现出随缓冲区尺度增大而增强的态势,在河岸带10 km缓冲区尺度上,土地利用方式对水质的解释度最高,是湘江水质治理的有效尺度.研究显示,湘江流域重金属污染与其他污染驱动因素不同但区域差异均较明显,因此污染治理应分类和因地施策.

关键词：湘江流域水质综合评价时空变化驱动机制土地利用

财政纵向失衡对创新驱动政策有效性的影响——基于国家创新型省份建设的准自然实验

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当代财经 2024年第9期 28-42页

作者：廖直东广东财经大学财政税务学院广东广州510320

创新驱动发展是支撑我国产业迈向中高端水平、经济实现高质量发展的关键和基础。基于国家创新型省份建设的准自然实验,采用2001—2019年省级面板数据,从创新数量和创新质量的双重视角考察了财政纵向失衡对创新驱动政策有效性的影响。研... 详细信息

创新驱动发展是支撑我国产业迈向中高端水平、经济实现高质量发展的关键和基础。基于国家创新型省份建设的准自然实验,采用2001—2019年省级面板数据,从创新数量和创新质量的双重视角考察了财政纵向失衡对创新驱动政策有效性的影响。研究表明:国家创新型省份建设存在创新数量效应和创新质量效应,财政纵向失衡会显著地抑制国家创新型省份建设的创新质量效应,但并不影响其创新数量效应。从创新投入的视角分析发现,国家创新型省份建设对创新人力资本投入和创新资金投入都有积极影响,但财政纵向失衡抑制了国家创新型省份建设的积极作用,引致财政纵向失衡对国家创新型省份建设政策有效性的影响在创新数量和创新质量之间产生分异。因此,为提升创新驱动政策有效性,我国应进一步完善财税体制,适度降低财政纵向失衡;优化地方财政支出结构,保障财政科技投入;总结国家创新型省份建设经验,纵深推进国家创新型省份建设。

关键词：财政纵向失衡创新驱动政策国家创新型省份建设创新数量创新质量

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Serum bile acid and unsaturated fatty acid profiles of non-alcoholic fatty liver disease in type 2 diabetic patients

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World Journal of Diabetes 2024年第5期15卷 898-913页

作者： Su-Su Feng Si-Jing Wang Lin Guo Pan-Pan Ma Xiao-Long Ye Ming-Lin Pan Bo Hang Jian-hua mao Antoine M Snijders Yi-Bing Lu Da-Fa Ding Department of Endocrinology The Second Affiliated Hospital of Nanjing Medical UniversityNanjing 210011Jiangsu ProvinceChina Biological Systems and Engineering Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720United States

BACKGROUND The understanding of bile acid(BA)and unsaturated fatty acid(UFA)profiles,as well as their dysregulation,remains elusive in individuals with type 2 diabetes mellitus(T2DM)coexisting with non-alcoholic fatty liver disease(NAFLD).Investigating these metabolites could offer valuable insights into the pathophy-siology of NAFLD in *** To identify potential metabolite biomarkers capable of distinguishing between NAFLD and *** A training model was developed involving 399 participants,comprising 113 healthy controls(HCs),134 individuals with T2DM without NAFLD,and 152 individuals with T2DM and *** validation encompassed 172 *** patients were divided based on liver fibrosis *** analytical approach employed univariate testing,orthogonal partial least squares-discriminant analysis,logistic regression,receiver operating characteristic curve analysis,and decision curve analysis to pinpoint and assess the diagnostic value of serum *** Compared to HCs,both T2DM and NAFLD groups exhibited diminished levels of specific *** UFAs,particular acids exhibited a positive correlation with NAFLD risk in T2DM,while theω-6:ω-3 UFA ratio demonstrated a negative *** ofα-linolenic acid andγ-linolenic acid were linked to significant liver fibrosis in *** validation cohort substantiated the predictive efficacy of these biomarkers for assessing NAFLD risk in T2DM *** This study underscores the connection between altered BA and UFA profiles and the presence of NAFLD in individuals with T2DM,proposing their potential as biomarkers in the pathogenesis of NAFLD.

关键词： Bile acid Non-alcoholic fatty liver disease Type 2 diabetes mellitus Unsaturated fatty acid

Risk factors for renal outcomes in children with antineutrophil cytoplasmic antibody-associated vasculitis:a nationwide retrospective study in China

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World Journal of Pediatrics 2024年第5期20卷 506-516页

作者： Li-Wen Tan Jun-Li Wan Chun-hua Zhu Hong Xu Zheng-Kun Xia Li-Zhi Chen Xiao-Chuan Wu Fang Wang Xiao-Rong Liu Cheng-Guang Zhao Xiao-Zhong Li Jian-hua mao Xiao-Wen Wang Wen-Yan huang Yu-Hong Li Jian-Jiang Zhang Shi-Pin Feng Jun Yang Jiao-Jiao Liu Chun-Lin Gao Li-Ping Rong Lan-Jun Shuai Ke Xu He-Jia Zhang Qiu Li Ai-hua Zhang Mo Wang Department of Nephrology Children’s Hospital of Chongqing Medical UniversityZhongshan 2nd Rd.136Chongqing400014China Ministry of Education Key Laboratory of Child Development and Disorders National Clinical Research Center for Child Health and DisordersChina International Science and Technology Cooperation Base of Child Development and Critical DisordersChildren’s Hospital of Chongqing Medical UniversityChongqingChina Chongqing Key Laboratory of Pediatrics Children’s Hospital of Chongqing Medical UniversityChongqingChina Department of Nephrology Children’s Hospital of Nanjing Medical University72 Guangzhou RoadNanjing210008China Department of Nephrology Children’s Hospital of Fudan UniversityNational Paediatric Medical Center of ChinaShanghaiChina Department of Pediatrics Jinling HospitalNanjing Medical UniversityNanjingChina Department of Pediatrics Jinling HospitalThe First School of Clinical MedicineSouthern Medical UniversityNanjingChina Department of Pediatrics Jinling HospitalMedical School of Nanjing UniversityNanjingChina Department of Pediatric Nephrology and Rheumatology The First Affiliated Hospital of Sun Yat-Sen UniversityGuangzhouChina Department of Pediatrics The Second Xiangya Hospital of Central South UniversityChangshaChina Department of Pediatrics Peking University First HospitalBeijingChina Department of Nephrology Beijing Children’s HospitalCapital Medical UniversityBeijing100045China National Center for Children’s Health BeijingChina Department of Pediatrics Shengjing Hospital of China Medical UniversityShenyangChina Department of Nephrology and Immunology Children’s Hospital of Soochow UniversitySuzhouChina Department of Nephrology Children HospitalZhejiang University School of MedicineHangzhouChina Department of Nephrology Wuhan Children’s Hospital(Wuhan Maternal and Child Healthcare Hospital)Tongji Medical CollegeHuazhong University of Science&TechnologyWuhanChina Department of Nephrology and Rheumatology Shanghai Children’s HospitalSchool

Background Pediatric antineutrophil cytoplasmic antibody-associated vasculitis(AAV)is a life-threatening systemic vasculitis featured by liability to renal ***,there are few studies on the risk factors and predictive models for renal outcomes of AAV in *** Data from 179 AAV children in multiple centers between January 2012 and March 2020 were collected *** risk factors and predictive model of end-stage renal disease(ESRD)in AAV were *** Renal involvement was the most typical manifestation(95.5%),and the crescent was the predominant pathological lesion(84.9%).The estimated glomerular filtration rate(eGFR)was evaluated in 114 patients,of whom 59.6%developed ESRD,and the median time to ESRD was 3.20 *** eGFR[P=0.006,odds ratio(OR)=0.955,95%confidence interval(CI)=0.924–0.987]and the percentages of global glomerulosclerosis(pGGS;P=0.018,OR=1.060,95%CI=1.010–1.112)were independent risk factors for ESRD of renal *** on the pGGS and eGFR at renal biopsy,we developed three risk grades of ESRD and one predictive *** Kaplan‒Meier curve indicated that renal outcomes were significantly different in different risk grades(P<0.001).Compared with serum creatinine at baseline,the predictive model had higher accuracy(0.86 versus 0.58,P<0.001)and a lower coefficient of variation(0.07 versus 0.92)in external *** Renal involvement is the most common manifestation of pediatric AAV in China,of which more than half deteriorates into *** predictive model based on eGFR at renal biopsy and the pGGS may be stable and accurate in speculating the risk of ESRD in AAV children.

关键词： Antineutrophil cytoplasmic antibody End-stage renal disease Glomerulonephritis Pediatric nephrology Vasculitis

Three-dimensional magnetic reconnection in complex multiple X-point configurations in an ancient solar-lunar terrestrial system

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Chinese Physics B 2024年第3期33卷 488-495页

作者：何向磊毛傲华孙萌萌邹继同王晓钢 School of Physics Harbin Institute of TechnologyHarbin 150001China Laboratory for Space Environment and Materials Science Harbin Institute of TechnologyHarbin 150001China

Magnetic reconnection processes in three-dimensional(3D)complex field configurations have been investigated in different magneto-plasma systems in space,laboratory,and astrophysical ***-dimensional(2D)features of magnetic reconnection have been well developed and applied successfully to systems with symmetrical property,such as toroidal fusion plasmas and laboratory experiments with an axial *** in asymmetric systems,the 3D features are inevitably different from those in the 2D *** reconnection structures in multiple celestial body systems,particularly star-planet-Moon systems,bring fresh insights to the understanding of the 3D geometry of ***,we take magnetic reconnection in an ancient solar-lunar terrestrial magneto-plasma system as an example by using its crucial parameters approximately estimated already and also some specific applications in pathways for energy and matter transports among Earth,ancient Moon,and the interplanetary magnetic field(IMF).Then,magnetic reconnection of the ancient lunar-terrestrial magnetospheres with the IMF is investigated numerically in this *** a 3D simulation for the Earth-Moon-IMF system,topological features of complex magnetic reconnection configurations and dynamical characteristics of magnetic reconnection processes are *** is found that a coupled lunar-terrestrial magnetosphere is formed,and under various IMF orientations,multiple X-points emerge at distinct locations,showing three typical magnetic reconnection structures in such a geometry,i.e.,the X-line,the triple current sheets,and the A-B null *** results can conduce to further understanding of reconnection physics in 3D for plasmas in complex magnetic configurations,and also a possible mechanism for energy and matters transport in evolutions of similar astrophysical systems.

关键词： magnetic reconnection multiple X-points complex magneto-plasma system

洞庭湖流域典型生态系统服务评估及权衡/协同关系研究

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长江流域资源与环境 2024年第2期33卷 310-321页

作者：廖江博毛德华邓美容湖南师范大学地理科学学院湖南长沙410081 洞庭湖流域生态环境变化与固碳增汇湖南省重点实验室湖南长沙410081

运用InVEST模型、GIS空间分析等方法,在子流域尺度上探究洞庭湖流域2000~2020年生态系统服务的时空特征,进而利用耦合协调度模型和地理探测器模型对水产出、水质净化、碳存储等三项关键生态系统服务进行权衡/协同分析。结果表明:(1)洞... 详细信息

运用InVEST模型、GIS空间分析等方法,在子流域尺度上探究洞庭湖流域2000~2020年生态系统服务的时空特征,进而利用耦合协调度模型和地理探测器模型对水产出、水质净化、碳存储等三项关键生态系统服务进行权衡/协同分析。结果表明:(1)洞庭湖流域生态系统服务的水产出服务和水质净化服务在不断地强化,而碳存储服务在不断地弱化。各项生态系统服务功能在空间上亦表现出差异性,2000和2010年水产出东南多于西北,到了2020年,西北部水产出出现最大值;N、P输出量的分布规律大体上上游少于下游,东部多于西部;碳存储则是在洞庭湖区最少,高值集中在上游区。(2)2000~2020年,整个流域两两生态系统服务之间处于中度协同水平,并向良好协同水平发展,两两生态系统服务存在明显的时空分布格局的差异。(3)洞庭湖流域生态系统服务之间非线性动态关系的形成受到自然和人文因素的影响,主要包括地形地势与气候变化、土地利用类型与分布格局,以及人类活动的干扰等,且自然因素的影响程度要大于人文因素。研究结果可为洞庭湖流域生态保护补偿机制建设提供理论依据。

关键词：生态系统服务权衡与协同 InVEST模型洞庭湖流域

基于量子反应均衡的政府与共享单车企业停车管理博弈分析

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控制与决策 2024年第2期39卷 641-648页

作者：张书婧贾顺平彭芃毛保华北京交通大学交通运输学院北京100044 北京交通大学综合交通运输大数据应用技术交通运输行业重点实验室北京100044 北京交通大学中国综合交通研究中心北京100044

共享单车停车问题是城市交通治理中最主要的问题之一,其表面为共享单车用户停车行为不规范、共享单车企业管理调度不及时所致,究其本质实为共享单车各利益主体缺乏有效协同治理机制、停车权责划分不清晰、成本分担失衡的结果.考虑政府... 详细信息

共享单车停车问题是城市交通治理中最主要的问题之一,其表面为共享单车用户停车行为不规范、共享单车企业管理调度不及时所致,究其本质实为共享单车各利益主体缺乏有效协同治理机制、停车权责划分不清晰、成本分担失衡的结果.考虑政府与共享单车企业的有限理性,建立扩展式博弈的量子反应均衡(QRE)模型分析双方停车管理博弈机理,并利用Gambit软件进行算例仿真分析.研究表明:双方博弈结果随理性程度增加逐渐趋向于基于完全理性的子博弈精炼纳什均衡,政府掌握更多企业运营信息有利于达到社会效用最大化的博弈结果;政府引入有效处罚措施或主导负责停车管理可以降低自身的财政支出和社会总成本,建立量化的处罚标准能够促进企业主动承担停车管理责任;有限理性程度、违停数量、激励机制和科技手段运行效率会影响企业的停车管理策略选择.

关键词：共享单车停车治理研究有限理性量子反应均衡扩展式博弈仿真

改进的大核卷积U-Net视网膜血管分割方法

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计算机工程与设计 2024年第5期45卷 1541-1548页

作者：顾茂华吴云贵州大学公共大数据国家重点实验室贵州贵阳550025 贵州大学计算机科学与技术学院贵州贵阳550025

眼底视网膜血管结构形态复杂、对比度低,且训练样本有限,易产生过拟合现象。针对以上问题,提出一种改进的大核卷积U-Net视网膜血管分割方法(large kernel residual U-Net, LKR-UNet)。减少U-Net下采样次数和每一层的通道数缓解模型过拟... 详细信息

眼底视网膜血管结构形态复杂、对比度低,且训练样本有限,易产生过拟合现象。针对以上问题,提出一种改进的大核卷积U-Net视网膜血管分割方法(large kernel residual U-Net, LKR-UNet)。减少U-Net下采样次数和每一层的通道数缓解模型过拟合和退化问题;使用大核残差卷积模块(large kernel residual convolution block, LKR-Block)充分提取视网膜血管的特征;通过级联空间通道注意力(cascaded spatial channel attention, CSCA)模块计算空间和通道注意力,提高分割的准确性。提出方法在DRIVE和CHASE_DB1数据集上进行消融实验,在两个数据集上的敏感度分别为84.04%和83.77%,AUC分别为97.82%和98.75%,F1-score分别为82.92%和84.67%。该方法较现有先进算法有一定提升,能有效进行视网膜血管分割。

关键词：深度学习医学图像处理视网膜血管分割大核卷积注意力机制过拟合 U型网络

数字经济对制造业产业结构升级的影响研究——以我国三大城市群为例

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城市问题 2024年第1期 4-15页

作者：毛艳华张超李松中山大学港澳珠江三角洲研究中心中山大学区域开放与合作研究院

城市群是制造业结构调整与高质量发展的主要空间载体。基于京津冀、长三角和粤港澳大湾区三大城市群2011—2021年数据,从城市层面探讨数字经济对三大城市群制造业产业结构升级的影响。研究发现:数字经济对三大城市群的制造业产业结构升... 详细信息

城市群是制造业结构调整与高质量发展的主要空间载体。基于京津冀、长三角和粤港澳大湾区三大城市群2011—2021年数据,从城市层面探讨数字经济对三大城市群制造业产业结构升级的影响。研究发现:数字经济对三大城市群的制造业产业结构升级有显著影响。其中,数字经济对京津冀和长三角城市群制造业产业结构高级化的影响作用要大于对其合理化的影响作用,大湾区城市群的情况则相反。数字经济对三大城市群制造业产业结构升级存在非线性影响特征。劳动技能结构提升是数字经济促进制造业产业结构升级的中介影响机制。数字经济对三大城市群制造业产业结构升级的影响在数字基础设施水平、数字化应用水平、数字产业化水平和数字化发展环境等维度存在差异。各地应立足自身特色优势,完善城市群内部协调沟通机制,强化制造业产业链上下游协调联动,健全数字技术人才培养体系,促进数字经济赋能制造业高质量发展。

关键词：数字经济制造业产业结构升级非线性影响城市群