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基于PMF模型的蔡家坡镇燃煤供暖电厂周边土壤重金属污染源解析及风险评价
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作者 张军 谢厚雨 +1 位作者 宿睿颖 耿雅妮 《干旱区资源与环境》 北大核心 2025年第9期147-156,共10页
以蔡家坡镇燃煤供暖电厂周边土壤为研究对象,采集并分析了燃煤供暖电厂周边38份表层土壤样本的重金属Cd、Sb、Cr、Zn、Cu、Ni、Pb和As含量。运用相关性分析、PMF模型分析土壤重金属的来源,结合基于源的潜在生态风险评价模型和基于源的... 以蔡家坡镇燃煤供暖电厂周边土壤为研究对象,采集并分析了燃煤供暖电厂周边38份表层土壤样本的重金属Cd、Sb、Cr、Zn、Cu、Ni、Pb和As含量。运用相关性分析、PMF模型分析土壤重金属的来源,结合基于源的潜在生态风险评价模型和基于源的健康风险评价模型分析不同污染源下的生态风险以及健康风险。结果表明:1)除As外,Pb、Ni、Cu、Zn、Cd、Cr平均含量均高于陕西省土壤背景值,其中Zn变异系数最高,受人类活动影响最大。2)研究区土壤重金属主要来源于工业源、交通源、农业源和综合源4种污染源。各污染源的贡献率分别为29.9%、28.5%、31.2%、10.4%。3)基于源的潜在生态风险-人体健康风险评价表明,工业源和农业源是研究区的首要管控源,Pb、Cd、As为主要管控因子。后续应针对这些重点污染源和污染因子制定防控措施,从而保障周边生态环境与人群健康。 展开更多
关键词 土壤重金属 pmf模型 生态风险评价 健康风险评价 蔡家坡镇
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基于PMF模型和地理探测器的金陵河下游土壤重金属源风险评价 被引量:1
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作者 李雨茹 段伟杰 +1 位作者 董嘉臻 张军 《环境科学》 北大核心 2025年第4期2512-2524,共13页
为了解金陵河下游土壤重金属的污染特征和污染来源,采集金陵河下游表层土壤41份,使用高精度X射线荧光光谱仪(HDXRF)测定8种重金属(Cr、Mn、Ni、Cu、Zn、As、Cd和Pb)含量.运用相关性分析、正定矩阵因子分解模型(PMF)分析土壤重金属的来源... 为了解金陵河下游土壤重金属的污染特征和污染来源,采集金陵河下游表层土壤41份,使用高精度X射线荧光光谱仪(HDXRF)测定8种重金属(Cr、Mn、Ni、Cu、Zn、As、Cd和Pb)含量.运用相关性分析、正定矩阵因子分解模型(PMF)分析土壤重金属的来源,利用基于源的潜在生态风险评价模型分析不同污染源下的生态风险,并借助地理探测器分析各污染源生态风险的影响因素.结果表明:①8种土壤重金属元素平均值均低于土壤污染风险筛选值,但都高于陕西省土壤背景值,其中Zn、Cd和Pb空间变异性大,主要受人类活动影响.②研究区土壤重金属主要来源于工业源、交通源、自然源和农业-工业混合源,各污染源贡献率分别为16.51%、23.68%、51.08%和8.73%,基于源的潜在生态风险评价表明,工业源、交通源、自然源和农业-工业混合源的潜在生态风险指数(RI)均值分别为34.11、85.03、16.76和21.19,Cd是优先控制元素,交通源为优先控制源.③不同污染源RI的主要影响因素存在显著差异,距重点企业距离、距公路距离、砂土含量和土地利用类型分别是工业源、交通源、自然源和农业-工业混合源的主要影响因子.研究结果可为流域土壤重金属环境管理和污染控制提供科学依据. 展开更多
关键词 土壤重金属 正定矩阵因子分解(pmf)模型 潜在生态风险指数 地理探测器 金陵河下游
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空间非均匀TOPMODEL与陆面模式SSiB4的耦合及流域水文模拟
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作者 王倩 丹利 邓慧平 《气候与环境研究》 北大核心 2025年第3期311-321,共11页
为了寻求合理简化的流域地形指数水文模型TOPMODEL(Topographic Index model)用于大尺度的陆面模式,推导了土壤表层饱和导水率k0、衰减因子f和地下水补给速率R空间都可变的扩展的TOPMODEL,并将f空间非均匀分布的TOPMODEL与陆面模式SSiB... 为了寻求合理简化的流域地形指数水文模型TOPMODEL(Topographic Index model)用于大尺度的陆面模式,推导了土壤表层饱和导水率k0、衰减因子f和地下水补给速率R空间都可变的扩展的TOPMODEL,并将f空间非均匀分布的TOPMODEL与陆面模式SSiB4耦合(SSiB4/GTOP)。通过耦合模型在f空间非均匀条件下进行实际流域的水文模拟,分析f空间非均匀对流域土壤湿度、蒸散发、地表径流、基流和总径流的影响。主要结论有:(1)k0和R的空间变化并不改变经典TOPMODEL原有关系式,只要定义新的地形指数,k0和R空间非均匀TOPMODEL与空间均匀的TOPMODEL并无区别;(2) f空间变化条件下由于局地的地下水埋深还与局地的f值有关,地形指数相同的区域具有水文相似性这一结论不再成立;(3)与f空间均匀的模拟结果相比较,f随海拔高度h i增加而线性减小使模拟的流域土壤湿度、地表径流和流域蒸散减小但使基流和总径流增加;(4) f空间非均匀对流域水文模拟结果有影响,但其影响明显小于流域地形因子的影响。 展开更多
关键词 空间非均匀性 扩展的TOPmodel推导 耦合模型SSiB4/GTOP 流域水文模拟 f空间非均匀影响
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Reduced mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor contributes to neurodegeneration in a model of spinal and bulbar muscular atrophy pathology 被引量:1
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作者 Yiyang Qin Wenzhen Zhu +6 位作者 Tingting Guo Yiran Zhang Tingting Xing Peng Yin Shihua Li Xiao-Jiang Li Su Yang 《Neural Regeneration Research》 SCIE CAS 2025年第9期2655-2666,共12页
Spinal and bulbar muscular atrophy is a neurodegenerative disease caused by extended CAG trinucleotide repeats in the androgen receptor gene,which encodes a ligand-dependent transcription facto r.The mutant androgen r... Spinal and bulbar muscular atrophy is a neurodegenerative disease caused by extended CAG trinucleotide repeats in the androgen receptor gene,which encodes a ligand-dependent transcription facto r.The mutant androgen receptor protein,characterized by polyglutamine expansion,is prone to misfolding and forms aggregates in both the nucleus and cytoplasm in the brain in spinal and bulbar muscular atrophy patients.These aggregates alter protein-protein interactions and compromise transcriptional activity.In this study,we reported that in both cultured N2a cells and mouse brain,mutant androgen receptor with polyglutamine expansion causes reduced expression of mesencephalic astrocyte-de rived neurotrophic factor.Overexpressio n of mesencephalic astrocyte-derived neurotrophic factor amelio rated the neurotoxicity of mutant androgen receptor through the inhibition of mutant androgen receptor aggregation.Conversely.knocking down endogenous mesencephalic astrocyte-derived neurotrophic factor in the mouse brain exacerbated neuronal damage and mutant androgen receptor aggregation.Our findings suggest that inhibition of mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor is a potential mechanism underlying neurodegeneration in spinal and bulbar muscular atrophy. 展开更多
关键词 androgen receptor mesencephalic astrocyte-derived neurotrophic factor mouse model NEURODEGENERATION neuronal loss neurotrophic factor polyglutamine disease protein misfolding spinal and bulbar muscular atrophy transcription factor
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基于PMF和蒙特卡洛模拟的锑矿区沉积物重金属来源、风险评估及优先控制因子分析
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作者 韦超前 肖艳桐 +3 位作者 段明宇 涂汉 李学先 吴攀 《环境科学学报》 北大核心 2025年第6期215-228,共14页
都柳江流域长期受锑矿采冶活动的影响,水系沉积物重金属污染突出,研究沉积物中重金属污染来源、风险对流域水环境安全及污染管控具有重要意义.本研究在分析都柳江水系沉积物中重金属含量、污染水平及对生态环境危害基础上,结合正定矩阵... 都柳江流域长期受锑矿采冶活动的影响,水系沉积物重金属污染突出,研究沉积物中重金属污染来源、风险对流域水环境安全及污染管控具有重要意义.本研究在分析都柳江水系沉积物中重金属含量、污染水平及对生态环境危害基础上,结合正定矩阵因子分解(PMF)受体模型和基于蒙特卡洛模拟的人体健康风险评价(HRA)模型对沉积物中重金属潜在来源、不同污染源影响下人体健康风险进行识别和评估,确定流域重金属污染防控优先管控因子.结果表明,流域水系沉积物中Sb、As污染明显,其中78%和26%的样点处于中度及以上污染水平,主要分布在流域上游支流废弃锑矿井分布区.生态风险评估表明流域84%和26%的样点Sb和As处于较强风险-极强风险水平.PMF解析结果显示,流域沉积物主要受矿业源影响,其次为自然源和混合源,各潜在来源贡献率分别为74.14%,13.97%和11.90%.HRA模型评估结果表明,沉积物重金属对于儿童及成人的非致癌风险概率分别为87.21%和55.89%,Sb和As为主要的非致癌风险贡献因子;致癌风险概率分别为79.24%和10.55%.其中儿童健康风险高于成人,经口摄入为主要暴露途径.根据沉积物重金属、污染来源与健康风险关系的分析结果,确定矿业源有关的Sb、As为优先管控因子.都柳江流域管理工作中,应重点关注支流废弃锑矿井分布区沉积物中Sb、As释放问题.研究结果可为矿区水环境污染防控提供科学依据. 展开更多
关键词 水系沉积物 SB As 正定矩阵因子分解(pmf)模型 蒙特卡洛模拟 优先控制因子
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APCS-MLR结合PMF模型解析大气PM_(2.5)中重金属元素来源及健康风险
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作者 彭家美 于瑞莲 +2 位作者 胡恭任 陈衍婷 吴雅清 《环境科学》 北大核心 2025年第11期7371-7384,共14页
为探究江西省南康市大气PM_(2.5)中重金属的污染特征、来源及健康风险,对该地区4个季节的大气PM_(2.5)进行采样,用ICP-MS分析测定11种重金属元素(Cu、Fe、Zn、Mn、Cd、Co、As、Ba、Pb、Cr和Ti)的含量,分析了Cu、Fe、Zn、Mn、Cd、Co、As... 为探究江西省南康市大气PM_(2.5)中重金属的污染特征、来源及健康风险,对该地区4个季节的大气PM_(2.5)进行采样,用ICP-MS分析测定11种重金属元素(Cu、Fe、Zn、Mn、Cd、Co、As、Ba、Pb、Cr和Ti)的含量,分析了Cu、Fe、Zn、Mn、Cd、Co、As、Ba和Pb的污染特征.结合富集因子分析、多变量分析方法(最大方差旋转因子分析)、APCS-MLR(绝对主成分线性回归)和PMF(正定矩阵因子分解)模型定量解析大气PM_(2.5)中重金属来源,并对重金属元素的人体健康风险进行评价.结果表明,采样期间研究区ρ(PM_(2.5))平均值为46.98μg·m^(-3),超过国家环境空气质量二级标准,且PM_(2.5)质量浓度在冬季最高.PM_(2.5)中9种重金属浓度年平均值高低依次为:Fe>Zn>Pb>As>Mn>Cu>Ba>Cd>Co.富集因子分析结果显示,研究区大气PM_(2.5)中大部分金属元素含量超过了江西省A层土壤环境背景值,除Fe和Ba外,其余重金属在环境中均相对富集,且受人类活动影响较大.因子分析表明,研究区大气PM_(2.5)的重金属污染源主要有4类:机动车源、工业源、燃煤源和自然源,Mn、Cu和Zn主要来源为机动车排放源,Co主要来源于以家具厂为代表的工业源,As、Cd和Pb主要来源于燃煤,Fe和Ba以自然源为主.APCS-MLR和PMF模型分析结果表明,由人类活动所引起的污染来源(机动车源、工业源和燃煤源)具有更高的贡献率,其中的燃煤源,在两个模型中的贡献率为20%~40%.健康风险分析结果显示,9种重金属均不存在非致癌风险,As和Mn对3类人群均存在潜在致癌风险,且对成年男性的致癌风险最大. 展开更多
关键词 PM_(2.5) 重金属 富集因子 绝对主成分线性回归(APCS-MLR) 正定矩阵因子分解(pmf) 健康风险
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基于PCA-PMF模型的城乡结合部沉积物重金属源解析
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作者 罗静 王承军 +2 位作者 刘小林 魏越波 胡春华 《环境科学与技术》 北大核心 2025年第10期161-171,共11页
为探究城乡结合部重金属的污染情况,文章以江西省南昌市前湖水系土壤沉积物为研究对象,分析沉积物中重金属Hg、Cd、Cr、Pb、As、Cu、Zn的含量和空间分布特征,采用地累积指数法评价重金属,并结合主成分分析和正定矩阵因子分解法(PMF)对... 为探究城乡结合部重金属的污染情况,文章以江西省南昌市前湖水系土壤沉积物为研究对象,分析沉积物中重金属Hg、Cd、Cr、Pb、As、Cu、Zn的含量和空间分布特征,采用地累积指数法评价重金属,并结合主成分分析和正定矩阵因子分解法(PMF)对重金属进行源解析。结果表明:Hg、Cd、Cr、Pb、As、Cu、Zn 7种重金属元素,质量分数均值分别为0.160、1.18、70.7、38.5、13.6、33.4、137 mg/kg,均高于长江流域水系沉积物背景值。地累积指数显示Cd和Hg为中度富集程度,该城乡结合部水域重金属元素污染程度高于自然区域但低于城市核心区域。结合主成分分析和PMF源解析模型识别出4种重金属污染源,其中农业活动源(32.5%)>自然源(28.3%)>工业源(25.6%)>交通污染源(13.6%),表明工农业生产等人为因素是造成城乡结合部沉积物重金属污染的主要原因。研究可为城乡结合部流域保护与土壤重金属风险防控提供科学依据。 展开更多
关键词 pmf模型 城乡结合部 重金属源解析
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基于APCS-MLR和PMF模型的石煤矿区及周边区域农田土壤重金属污染来源解析 被引量:3
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作者 董天浩 潘淑芳 +4 位作者 张仁杰 姜立恒 郭焱 纪雄辉 谢运河 《环境科学》 北大核心 2025年第5期3209-3219,共11页
为了探究石煤开采带来的农田土壤重金属污染风险,对某石煤矿区及周边区域农田土壤进行了采样分析及污染源解析.结果表明:①该石煤矿区及周边农田土壤重金属污染风险很高.按内梅罗综合污染指数确定的轻污染风险以上的采样点占比为61.6%,... 为了探究石煤开采带来的农田土壤重金属污染风险,对某石煤矿区及周边区域农田土壤进行了采样分析及污染源解析.结果表明:①该石煤矿区及周边农田土壤重金属污染风险很高.按内梅罗综合污染指数确定的轻污染风险以上的采样点占比为61.6%,其中重污染风险采样点占比达21.9%.研究区土壤Cd污染很严重,超出风险筛选值和风险管制值的采样点占比分别为71.5%和18.5%.②土壤Cd、Zn、Ni、Cu和As之间,As、Hg和Pb之间,Cr与As和Ni,Hg与Zn、Ni和Cu,均存在极显著正相关关系.Cd与Cr和Pb的相关性均不显著,其余重金属元素组合均存在显著正相关关系.③基于不同受体模型对研究区进行土壤重金属污染来源解析,识别出3个污染来源,即石煤开采源,大气沉降源和自然源.APCS-MLR模型判定土壤Cd、As、Cu、Zn和Ni主要受石煤开采源影响,Pb和Hg主要受大气沉降源影响,Cr主要受自然源影响;3个污染源的贡献率依次为43.2%、31.5%和25.3%.PMF模型的源解析结果与之总体上相同,但判定土壤Cd和Hg均受石煤开采-大气沉降混合源影响;3个污染源的贡献率依次为45.0%、34.5%和20.5%.研究表明,石煤矿区及周边区域农田土壤有较大的重金属污染风险,联合使用两种受体模型能够更合理地判别各土壤重金属主要的污染来源. 展开更多
关键词 土壤重金属 石煤 源解析 APCS-MLR模型 pmf模型
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自组织神经映射网络(SOM)结合PMF模型解析某湿地公园沉积物金属来源
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作者 韩晨露 胡恭任 +2 位作者 于瑞莲 赵大伟 吴雅清 《环境科学》 北大核心 2025年第8期5070-5081,共12页
评价湿地沉积物金属污染现状及生态风险并分析其来源,对保障湿地的正常生态功能和可持续发展具有重要意义.为研究由围堰养殖场和农田改建而来的某滨海湿地公园是否存在金属污染问题,在公园内采集26个表层沉积物样品,分析测定金属元素(Li... 评价湿地沉积物金属污染现状及生态风险并分析其来源,对保障湿地的正常生态功能和可持续发展具有重要意义.为研究由围堰养殖场和农田改建而来的某滨海湿地公园是否存在金属污染问题,在公园内采集26个表层沉积物样品,分析测定金属元素(Li、Be、V、Cr、Co、Cu、Zn、Cd、Pb、As和Mn)的含量,结合空间分布特征,采用地累积指数、污染负荷指数以及潜在生态风险指数对研究区域进行金属污染评价,利用相关性-聚类分析、自组织神经映射网络(SOM)和正定矩阵因子分解(PMF)解析金属元素的来源及其贡献率.结果表明:(1)研究区表层沉积物中金属元素含量平均值均超过福建省土壤元素背景值,Cd和Zn的变异性较强,受人为影响显著;(2)地累积指数、污染负荷指数和潜在生态风险指数评价结果表明,该公园整体处于低、中污染等级,其中Li和Zn的积累程度较大,而Cd的潜在生态风险达到了较高水平;(3)综合相关性-聚类、SOM和PMF分析表明11种金属污染来源可划分为3类,其中Cr、Cu、Zn和Pb主要源于交通源(29.72%),Li、Be、Mn、V、Co和As主要源于自然源(44.89%),Cd和Zn则主要来源于农业活动(25.39%). 展开更多
关键词 滨海湿地公园 表层沉积物 金属污染评价 自组织神经映射网络(SOM) 正定矩阵因子分解(pmf) 来源解析
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基于PMF和APCS-MLR模型的会仙湿地沉积物重金属源解析及污染风险评价
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作者 刘涛 沈利娜 +1 位作者 于奭 秦金福 《环境科学》 北大核心 2025年第9期6024-6036,共13页
基于会仙湿地14个点位沉积物样品测试分析结果,探讨(Cu、Pb、Cd、Cr、Zn、Ni、Hg和As)8种重金属的含量特征,并运用地累积指数法和潜在生态风险指数对重金属进行风险评估,结合相关性分析、聚类分析、绝对主成分-多元线性回归(APCS-MLR)... 基于会仙湿地14个点位沉积物样品测试分析结果,探讨(Cu、Pb、Cd、Cr、Zn、Ni、Hg和As)8种重金属的含量特征,并运用地累积指数法和潜在生态风险指数对重金属进行风险评估,结合相关性分析、聚类分析、绝对主成分-多元线性回归(APCS-MLR)和正定矩阵因子分解(PMF)等多种方法,识别和定量解析污染源及贡献.结果表明:①8种重金属的平均含量均高于背景值,其中Cd超过《土壤环境质量-农用地土壤污染风险管控标准》(GB 15618-2018)筛选值.②地累积指数评价结果表明,Cd属于中度污染,Zn属于偏中度污染,Hg、Ni、Cr和Pb属于轻度污染,As和Cu属于无污染.③潜在风险指数评价结果表明,Cd(245.91)属于很强生态风险,Hg(134.59)属于强生态风险,其它元素均属于轻微生态风险;研究区综合生态风险指数均值为433.33,整体呈现出强的潜在生态风险.④APCS-MLR识别出4个污染源,分别为农业源、自然与农业源、大气沉降与生活源和未识别源(交通与农业源),贡献率分别为33.16%、15.75%、9.50%和41.59%;PMF识别出3个污染源,分别为大气沉降与生活源、自然与农业源和交通与农业源,贡献率分别为21.92%、35.24%和42.84%. 展开更多
关键词 沉积物 重金属 源解析 正定矩阵因子分解(pmf) 绝对主成分-多元线性回归(APCS-MLR)
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Development and validation of a machine learning model for diagnosis of ischemic heart disease using single-lead electrocardiogram parameters 被引量:1
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作者 Basheer Abdullah Marzoog Peter Chomakhidze +11 位作者 Daria Gognieva Artemiy Silantyev Alexander Suvorov Magomed Abdullaev Natalia Mozzhukhina Darya Alexandrovna Filippova Sergey Vladimirovich Kostin Maria Kolpashnikova Natalya Ershova Nikolay Ushakov Dinara Mesitskaya Philipp Kopylov 《World Journal of Cardiology》 2025年第4期76-92,共17页
BACKGROUND Ischemic heart disease(IHD)impacts the quality of life and has the highest mortality rate of cardiovascular diseases globally.AIM To compare variations in the parameters of the single-lead electrocardiogram... BACKGROUND Ischemic heart disease(IHD)impacts the quality of life and has the highest mortality rate of cardiovascular diseases globally.AIM To compare variations in the parameters of the single-lead electrocardiogram(ECG)during resting conditions and physical exertion in individuals diagnosed with IHD and those without the condition using vasodilator-induced stress computed tomography(CT)myocardial perfusion imaging as the diagnostic reference standard.METHODS This single center observational study included 80 participants.The participants were aged≥40 years and given an informed written consent to participate in the study.Both groups,G1(n=31)with and G2(n=49)without post stress induced myocardial perfusion defect,passed cardiologist consultation,anthropometric measurements,blood pressure and pulse rate measurement,echocardiography,cardio-ankle vascular index,bicycle ergometry,recording 3-min single-lead ECG(Cardio-Qvark)before and just after bicycle ergometry followed by performing CT myocardial perfusion.The LASSO regression with nested cross-validation was used to find the association between Cardio-Qvark parameters and the existence of the perfusion defect.Statistical processing was performed with the R programming language v4.2,Python v.3.10[^R],and Statistica 12 program.RESULTS Bicycle ergometry yielded an area under the receiver operating characteristic curve of 50.7%[95%confidence interval(CI):0.388-0.625],specificity of 53.1%(95%CI:0.392-0.673),and sensitivity of 48.4%(95%CI:0.306-0.657).In contrast,the Cardio-Qvark test performed notably better with an area under the receiver operating characteristic curve of 67%(95%CI:0.530-0.801),specificity of 75.5%(95%CI:0.628-0.88),and sensitivity of 51.6%(95%CI:0.333-0.695).CONCLUSION The single-lead ECG has a relatively higher diagnostic accuracy compared with bicycle ergometry by using machine learning models,but the difference was not statistically significant.However,further investigations are required to uncover the hidden capabilities of single-lead ECG in IHD diagnosis. 展开更多
关键词 Ischemic heart disease Single-lead electrocardiography Computed tomography myocardial perfusion Prevention Risk factors Stress test Machine learning model
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基于分类回归树和PMF模型的土壤重金属影响因素和来源分析
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作者 张云逸 罗宇洁 +4 位作者 蒋玉莲 余飞 余亚伟 王佳彬 钟克强 《环境科学》 北大核心 2025年第9期6056-6065,共10页
为探究镇域尺度下土壤重金属来源及其影响因素,以重庆市东南部某镇为研究区域,共采集280份表层土壤样品,分析了As、Cd、Cr、Cu、Hg、Ni、Pb、Zn、pH和Corg等指标.采用地累积指数法对区域土壤重金属进行评价,采用相关分析、冷热点分析、... 为探究镇域尺度下土壤重金属来源及其影响因素,以重庆市东南部某镇为研究区域,共采集280份表层土壤样品,分析了As、Cd、Cr、Cu、Hg、Ni、Pb、Zn、pH和Corg等指标.采用地累积指数法对区域土壤重金属进行评价,采用相关分析、冷热点分析、分类回归树模型及正定矩阵因子分解(PMF)模型对8种重金属进行来源分析.结果表明,研究区As、Cd、Cr、Cu、Hg、Ni、Pb和Zn等8种重金属含量平均值均高于重庆市土壤背景值,土壤主要风险因子为Cd、As和Hg;与居民点距离是影响土壤Hg最关键因素,与公路距离是影响土壤Cd最关键因素,与工矿企业距离是影响As和Pb最关键因素;研究区重金属主要来源有4种,分别为农业生产源、交通污染与自然母质复合源、采矿活动源和自然母质源,贡献率分别为16%、23%、31%和30%.Hg主要受到农业生产源影响,Cd主要受到交通污染和自然母质复合源影响,As和Pb主要受到采矿活动源影响,Cu、Ni、Zn和Cr受到自然母质源影响. 展开更多
关键词 分类回归树模型 正定矩阵因子分解(pmf)模型 来源分析 土壤重金属 相对重要性
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Predictive model for early postoperative stomal complications in colorectal cancer:A systematic review
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作者 Payal Kaw Ashok Kumar 《World Journal of Gastrointestinal Oncology》 2025年第8期393-401,共9页
BACKGROUND Stomal complications though small in early postoperative period,but poses significant morbidity,therapeutic challenge,delay in adjuvant treatment and sometimes even leads to mortality.Predictive model for e... BACKGROUND Stomal complications though small in early postoperative period,but poses significant morbidity,therapeutic challenge,delay in adjuvant treatment and sometimes even leads to mortality.Predictive model for early detection of stomal complications is important to improve the outcome.A model including patients and disease related factors,intraoperative surgical techniques and biochemical markers would be a better determinant to anticipate early stomal complications.Incorporation of emerging tools and technology such as artificial intelligence(AI),will further improve the prediction.AIM To identify various risk factors and models for prediction of early post operative stomal complications in colorectal cancer(CRC)surgery.METHODS Published literatures on early postoperative stomal complications in CRC surgery were systematically reviewed between 1995 and 2024 from online search engines PubMed and MEDLINE.RESULTS Twenty-four observational studies focused on identifying various risk factors for early post operative stomal complications in CRC surgery were analyzed.Stomal complications in CRC are influenced by several factors such as disease factors,patient-specific characteristics,and surgical techniques.There are some biomarkers and tools loke AI which may play significant roles in early detection.CONCLUSION Careful analysis of these factors,changes in biochemical parameters,and application of AI,a predictive model for stomal complications can be generated,to help in early detection,prompt action to achieve better outcomes. 展开更多
关键词 Stomal complications Colorectal cancer Predictive model Artificial intelligence Patient’factors Surgeon factor Disease factors Biochemical markers
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Modeling compositional heterogeneity resolves deep phylogeny of flowering plants
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作者 Yongli Wang Yan-Da Li +3 位作者 Shuo Wang Erik Tihelka Michael S.Engel Chenyang Cai 《Plant Diversity》 2025年第1期13-20,共8页
Angiosperms experienced one of the most remarkable radiations of land plants and are now the dominant autotrophs in terrestrial ecosystems.Recent phylogenomic studies based on large-scale data from plastid,mitochondri... Angiosperms experienced one of the most remarkable radiations of land plants and are now the dominant autotrophs in terrestrial ecosystems.Recent phylogenomic studies based on large-scale data from plastid,mitochondrial,or nuclear transcriptomes/genomes and increased taxon sampling have provided unprecedent resolution into the phylogeny of flowering plants.However,owing to ancient rapid radiations,the interrelationships among the five lineages of Mesangiospermae,the vast majority of angiosperms,remain contentious.Here we show that,although plastid and mitochondrial genomes lack sufficient phylogenetic signal for resolving deeper phylogeny,the relationships among five mesangiosperm lineages can be confidently resolved under better-fitting models using genome-scale data.According to our Bayesian cross-validation and model test in a maximum likelihood framework,siteheterogeneous models(e.g.,CAT-GTR+G4,LG+C20+F+G)outperform site-homogeneous or partition models often used in previous studies.Under site-heterogeneous models,the approximately unbiased test favored our preferred tree recovered from various datasets:Ceratophyllales(coontails)are robustly recovered as sister to monocots,and they together are sister to the clade comprising magnoliids,Chloranthales,and eudicots.Our phylogenomic analyses resolve the last enigma of the deeper phylogeny of angiosperms and emphasize the efficacy of modeling compositional heterogeneity in resolving rapid radiations of plants. 展开更多
关键词 ANGIOSPERMS Ceratophyllales PHYLOGENOMICS Radiation Methodological factors CAT model
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Neural Tucker Factorization
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作者 Peng Tang Xin Luo 《IEEE/CAA Journal of Automatica Sinica》 2025年第2期475-477,共3页
Dear Editor,This letter presents a novel latent factorization model for high dimensional and incomplete (HDI) tensor, namely the neural Tucker factorization (Neu Tuc F), which is a generic neural network-based latent-... Dear Editor,This letter presents a novel latent factorization model for high dimensional and incomplete (HDI) tensor, namely the neural Tucker factorization (Neu Tuc F), which is a generic neural network-based latent-factorization-of-tensors model under the Tucker decomposition framework. 展开更多
关键词 neu tuc f neural tucker factorization latent factorization model high dimensional tensor tucker decomposition framework neural network incomplete tensor latent factorization
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Analysis of risk factors and predictive value of a nomogram model for sepsis in patients with diabetic foot
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作者 Wen-Wen Han Jian-Jiang Fang 《World Journal of Diabetes》 2025年第4期144-152,共9页
BACKGROUND Sepsis is a severe complication in hospitalized patients with diabetic foot(DF),often associated with high morbidity and mortality.Despite its clinical significance,limited tools exist for early risk predic... BACKGROUND Sepsis is a severe complication in hospitalized patients with diabetic foot(DF),often associated with high morbidity and mortality.Despite its clinical significance,limited tools exist for early risk prediction.AIM To identify key risk factors and evaluate the predictive value of a nomogram model for sepsis in this population.METHODS This retrospective study included 216 patients with DF admitted from January 2022 to June 2024.Patients were classified into sepsis(n=31)and non-sepsis(n=185)groups.Baseline characteristics,clinical parameters,and laboratory data were analyzed.Independent risk factors were identified through multivariable logistic regression,and a nomogram model was developed and validated.The model's performance was assessed by its discrimination(AUC),calibration(Hosmer-Lemeshow test,calibration plots),and clinical utility[decision curve analysis(DCA)].RESULTS The multivariable analysis identified six independent predictors of sepsis:Diabetes duration,DF Texas grade,white blood cell count,glycated hemoglobin,Creactive protein,and albumin.A nomogram integrating these factors achieved excellent diagnostic performance,with an AUC of 0.908(95%CI:0.865-0.956)and robust internal validation(AUC:0.906).Calibration results showed strong agreement between predicted and observed probabilities(Hosmer-Lemeshow P=0.926).DCA demonstrated superior net benefit compared to extreme intervention scenarios,highlighting its clinical utility.CONCLUSION The nomogram prediction model,based on six key risk factors,demonstrates strong predictive value,calibration,and clinical utility for sepsis in patients with DF.This tool offers a practical approach for early risk stratification,enabling timely interventions and improved clinical management in this high-risk population. 展开更多
关键词 Diabetic foot SEPSIS Risk factors NOMOGRAM Prediction model
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Prognostic models for lung cancer in smokers and nonsmokers:an updated systematic review and meta-analysis
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作者 Xinyue Pan Boxing Feng +4 位作者 Ying Chen Junfeng Wang Xuanqi Pan Taihing Lam Jing Pan 《Oncology and Translational Medicine》 2025年第3期112-117,共6页
Background:Lung cancer is the leading cause of cancer-related mortality,and while low-dose computed tomography screening may reduce mortality,emerging prognostic models show superior discriminative efficacy compared t... Background:Lung cancer is the leading cause of cancer-related mortality,and while low-dose computed tomography screening may reduce mortality,emerging prognostic models show superior discriminative efficacy compared to age-and smoking history-based screening.However,further research is needed to assess their reliability in predicting lung cancer risk in high-risk patients.Methods:This study evaluated the predictive performance and quality of existing lung cancer prognostic models through a systematic review and meta-analysis.A comprehensive search was conducted in PubMed,Cochrane,Web of Science,CNKI,and Wanfang for articles published between January 1,2000,and February 13,2025,identifying population-basedmodels incorporating all available modeling data.Results:Among 72 analyzed studies,models were developed from Asian(28 studies,including 23 Chinese cohorts)and European/American(48 studies)populations,with only 6 focusing on nonsmokers.Twenty-one models included genetic markers,15 used clinical factors,and 40 integrated epidemiological predictors.Although 37 models underwent external validation,only 4 demonstrated minimal bias and clinical applicability.A meta-analysis of 11 repeatedly validated models revealed calibration and discrimination,though some lacked calibration data.Conclusions:Few lung cancer prognostic models exist for nonsmokers.Most models exhibit poor predictive performance in external validations,with significant bias and limited application scope.Widespread external validation,standardized model development,and reporting techniques are needed to accurately identify high-risk individuals and ensure applicability across diverse populations. 展开更多
关键词 Lung cancer Prognostic model SCREEN Risk factor
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Development of a Two-Dimensional Hydrodynamic Model to Simulate Rip Currents in the Bai Dai-Cam Ranh Coast, Vietnam
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作者 Ngo Nam Thinh Nguyen Thi Bay 《Journal of Environmental & Earth Sciences》 2025年第4期203-216,共14页
Rip currents are a significant threat to swimmers worldwide,responsible for numerous drowning incidents each year.In Vietnam,Bai Dai Beach in Cam Ranh Bay,Khanh Hoa Province,has experienced an increase in drowning eve... Rip currents are a significant threat to swimmers worldwide,responsible for numerous drowning incidents each year.In Vietnam,Bai Dai Beach in Cam Ranh Bay,Khanh Hoa Province,has experienced an increase in drowning events due to rip currents in recent years.To address this issue,a comprehensive study was conducted based on developing a depth-averaged 2D hydrodynamic model to simulate rip currents in the Bai Dai-Cam Ranh coast.The HYDIST-2D numerical model was applied to simulate the rip current evolution in space and time for the study area.The results showed that the HYDIST-2D numerical model can accurately predict the location,magnitude,and microstructure of rip currents,including rip current speed,width,and length.The simulation results revealed that the rip current speed is greater during the low tide phase,with an average speed of 0.5 m s^(-1),while during high tide,the rip current speed is lower,around 0.1–0.8 m s^(-1).The width and length of the rip current also vary with the tide phase,with a wider and longer rip current observed during the low tide phase.The results also showed that the rip current speed and microstructure are influenced by the wave features,tide current,and bathymetry of the study area.The present study provides valuable insights into the dynamics of rip currents in the Bai Dai-Cam Ranh coast.The findings can be used to support the management of bathing activities and provide early warnings for potential risks associated with rip currents. 展开更多
关键词 HYDIST model SWIMMERS RIP Hydrodynamic Factors Breaking Waves
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Advancements and challenges in esophageal carcinoma prognostic models:A comprehensive review and future directions
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作者 Jia Chen Qi-Chang Xing 《World Journal of Gastrointestinal Oncology》 2025年第2期311-314,共4页
In this article,we comment on the article published by Yu et al.By employing LASSO regression and Cox proportional hazard models,the article identified nine significant variables affecting survival,including body mass... In this article,we comment on the article published by Yu et al.By employing LASSO regression and Cox proportional hazard models,the article identified nine significant variables affecting survival,including body mass index,Karnofsky performance status,and tumor-node-metastasis staging.We firmly concur with Yu et al regarding the vital significance of clinical prediction models(CPMs),including logistic regression and Cox regression for assessment in esophageal carcinoma(EC).However,the nomogram's limitations and the complexities of integrating genetic factors pose challenges.The integration of immunological data with advanced statistics offers new research directions.High-throughput sequencing and big data,facilitated by machine learning,have revolutionized cancer research but require substantial computational resources.The future of CPMs in EC depends on leveraging these technologies to improve predictive accuracy and clinical application,addressing the need for larger datasets,patientreported outcomes,and regular updates for clinical relevance. 展开更多
关键词 Predictive model Machine learning Esophageal carcinoma Survival rate FACTORS
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Predictive model for sphincter preservation in lower rectal cancer
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作者 Yajnadatta Sarangi Ashok Kumar 《World Journal of Clinical Oncology》 2025年第8期201-219,共19页
BACKGROUND Low rectal cancer poses a significant surgical challenge because of its close proximity to the anal sphincter,often requiring radical resection with permanent colostomy to achieve oncological safety.Revisit... BACKGROUND Low rectal cancer poses a significant surgical challenge because of its close proximity to the anal sphincter,often requiring radical resection with permanent colostomy to achieve oncological safety.Revisited rectal anatomy,advances in surgical techniques and neoadjuvant therapies have enabled the possibility of sphincter-preserving procedures,however,it is uniformly not applicable.Selecting appropriate candidates for sphincter preservation is crucial,as an illadvised approach may compromise oncological outcome or lead to poor functional outcomes.Currently there is no consensus-which clinical,anatomical,or molecular factors most accurately predict the feasibility of sphincter-preserving surgery(SPS)in this subset of patients.By identifying these predictors,the study seeks to support improved patient selection,enhance surgical planning,and ultimately contribute to better functional and oncological outcomes in patients with low rectal cancer.AIM To identify predictive factors that determine the feasibility of SPS in patients with low rectal cancer.METHODS A comprehensive literature search was conducted using PubMed/MEDLINE databases.The search focused on various factors influencing the feasibility of SPS in low rectal cancer.These included patient-related factors,anatomical considerations,findings from different imaging modalities,advancements in diagnostic tools and techniques,and the role of neoadjuvant chemoradiotherapy.The relevance of each factor in predicting the potential for sphincter preservation was critically analyzed and presented based on the current evidence RESULTS Multiple studies have identified a range of predictive factors influencing the feasibility of SPS in low rectal cancer.Patient-related factors include age,sex,preoperative continence status,comorbidities,and body mass index.Anatomical considerations,such as tumor distance from the anal verge,involvement of the external anal sphincter,and levator ani muscles,also play a critical role.Additionally,a favourable response to neoadjuvant chemoradiotherapy has been associated with improved suitability for sphincter preservation.Several biomarkers,such as inflammatory markers like interleukins and C-reactive protein,as well as tumor markers like carcinoembryonic antigen,are important.Molecular markers,including BRAF and KRAS mutations and microsatellite instability status,have been linked to prognosis and may further guide decision-making regarding sphincter-preserving approaches.Artificial intelligence(AI)can further add in to select an ideal patient for sphincter preservation.CONCLUSION SPS is feasible in low rectal cancer and depends on patient factors,tumor anatomy and biology,preoperative treatment response,and biomarkers.In addition,tools and technology including AI can further help in selecting an ideal patient for long term optimal outcome. 展开更多
关键词 Low rectal cancer SURGERY Sphincter preservation Predictive model FACTORS
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