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Journal of Intensive Medicine 2024年第4期4卷 537-538页

作者： Weifeng Shang Hang Qian sheng Zhang Xiaojun Pan Sisi Huang Zhenliang Wen jiao Liu Dechang Chen Department of Critical Care Medicine Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghaiChina

To the Editor,Previous studies have demonstrated close associations of specific immune cell profiles in the occurrence and development of COVID-19.[1,2]However,due to confounding factors and reverse causality in traditional observational studies,it remains unclear whether these associations reflect a causal *** randomization(MR)is a reliable method of causal inferences that uses genetic variants(usually single-nucleotide polymorphisms[SNPs])as instrumental variables(IVs)to estimate the causal effect of exposure on outcome.

关键词： severity immune random

A comprehensive review of the modeling of transport phenomenon in the flow channels of polymer electrolyte membrane fuel cells

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Frontiers of Chemical Science and Engineering 2024年第8期18卷 123-161页

作者： Niyi Olukayode Shenrong Ye Mingruo Hu Yanjun Dai Rui Chen sheng Sui Institute of Fuel Cell Shanghai Jiao Tong UniversityShanghai 200240China Institute of Refrigeration and Cryogenics Shanghai Jiao Tong UniversityShanghai 200240China Low Carbon Engineering Loughborough UniversityLoughborough Leicestershire LE113TUUK

Reactant gas and liquid water transport phenomena in the flow channels are complex and critical to the performance and durability of polymer electrolyte membrane fuel *** polymer membrane needs water at an optimum level for proton *** management involves the prevention of dehydration,waterlogging,and the cell’s subsequent performance decline and *** process requires the study and understanding of internal two-phase *** experimental visualization techniques are used to study two-phase flows in polymer electrolyte membrane fuel ***,the experiments have limitations in in situ measurements;they are also expensive and time *** contrast,numerical modeling is cheaper and faster,providing insights into the complex multiscale processes occurring across the components of the polymer electrolyte membrane fuel *** paper introduces the recent design of flow *** reviews the numerical modeling techniques adopted for the transport phenomena therein:the two-fluid,multiphase mixture,volume of fluid,lattice Boltzmann,and pressure drop ***,this work describes,compares,and analyses the models’approaches and reviews the representative results of some selected ***,the paper summarizes the modeling perspectives,emphasizing future directions with some recommendations.

关键词： two-phase flows numerical model flow channel polymer electrolyte membrane fuel cells water management

“城市⁃街区”尺度下绿地景观格局对雨洪滞蓄效能的影响研究进展

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应用生态学报 2024年第2期35卷 533-542页

作者：黎贝焦胜周敏周媛湖南大学建筑与规划学院长沙410000 西南民族大学建筑学院成都610000

在雨洪灾害频发和存量规划的背景下,阐明不同尺度下城市绿地景观格局与雨洪滞蓄效能间的关系与机制,成为实现有限城市绿地的最大雨洪滞蓄效能并提高城市防洪能力的关键科学问题。本文系统归纳了城市和街区尺度下绿地景观格局对雨洪滞蓄... 详细信息

在雨洪灾害频发和存量规划的背景下,阐明不同尺度下城市绿地景观格局与雨洪滞蓄效能间的关系与机制,成为实现有限城市绿地的最大雨洪滞蓄效能并提高城市防洪能力的关键科学问题。本文系统归纳了城市和街区尺度下绿地景观格局对雨洪滞蓄效能的影响要素、作用机制和尺度差异。并基于研究结论差异致因和研究不足,指出未来应增加流域尺度研究、拓展三维绿地景观格局的研究,还应分别聚焦城市和城郊区域,针对不同雨洪敏感区和街区结构,建立具有雨洪过程指示意义的研究指数集合,以定量揭示城市和街区尺度的绿地景观格局对雨洪过程作用机理,为城市规划及城市雨洪安全格局构建提供理论指导。

关键词：城市尺度街区尺度绿地景观格局雨洪滞蓄

典型旅游城市土壤重金属特定源生态风险评价及优先控制源分析

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环境科学 2024年第8期45卷 4837-4846页

作者：李军高占栋台喜生焦亮臧飞兰州城市学院城市环境学院兰州730070 西北师范大学甘肃省绿洲资源环境与可持续发展重点实验室兰州730070 兰州大学草地农业科技学院兰州730020

为了解西北旅游城市土壤重金属的污染现状、分布特征及污染来源,选择敦煌市主城区土壤为研究对象,采集并分析了表层土壤重金属As、Cd、Cr、Cu、Hg、Ni、Pb和Zn的含量特征.采用地累积指数法和改进内梅罗污染指数法量化土壤重金属污染水平... 详细信息

为了解西北旅游城市土壤重金属的污染现状、分布特征及污染来源,选择敦煌市主城区土壤为研究对象,采集并分析了表层土壤重金属As、Cd、Cr、Cu、Hg、Ni、Pb和Zn的含量特征.采用地累积指数法和改进内梅罗污染指数法量化土壤重金属污染水平,利用聚类分析和正定矩阵因子分解(PMF)模型定量解析重金属污染来源,并应用PMF模型和综合生态风险指数相结合的方法解析各污染源对生态风险的贡献率.结果表明,除As和Ni之外,Cd、Cr、Cu、Hg、Pb和Zn含量的均值均高于甘肃省土壤元素背景值,但所有元素的含量均低于《土壤环境质量建设用地土壤污染风险管控标准(试行)》(GB 36600-2018)中建设用地的风险筛选值,其中Cd、Pb和Hg的富集较为严重,超标率均高于90%.地累积指数评价结果显示,研究区土壤以Hg污染为主,也存在不同程度的Cd、Cr、Cu、Pb和Zn污染.改进内梅罗污染指数结果表明,土壤的综合污染程度为无污染至中度污染,总体上为轻度污染.PMF模型源解析表明,研究区土壤重金属受自然源、工业降尘源、工业源、交通源和综合源的影响,贡献率依次为29.28%、25.86%、20.13%、16.5%和8.23%.特定源-综合生态风险评价模型分析表明,工业降尘源为优先控制污染源,Hg为生态风险优先控制污染元素.

关键词：城市土壤地累积指数污染评价生态风险溯源解析

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聚芳硫醚砜的研究——合成、结构及热稳定性

华东化工学院学报 1984年第2期 161-168页

作者：胡福增焦扬声李世瑨

以4,4′-二氯二苯砜与硫化钠缩聚,制得了线型聚芳硫醚砜。以二甲基亚砜为溶剂,碳酸钠为催化剂,反应可在常压、较低温度下进行,产率90%以上。产物分子量约一万,对数比浓粘度约33 cm~3/g,熔化温度250～270℃,热分解温度为465℃,表观热分... 详细信息

以4,4′-二氯二苯砜与硫化钠缩聚,制得了线型聚芳硫醚砜。以二甲基亚砜为溶剂,碳酸钠为催化剂,反应可在常压、较低温度下进行,产率90%以上。产物分子量约一万,对数比浓粘度约33 cm~3/g,熔化温度250～270℃,热分解温度为465℃,表观热分解活化能为37.8千卡/摩尔。元素分析、红外光谱、核磁共振表明,该聚合物的主要结构为; X-衍射表明,该聚合为是部分结晶的。

关键词：热稳定性热力学性质聚芳硫醚砜热失重大分子化合物聚合物比浓粘度 IR 光谱红外光谱热分解温度反应温度无定形衍射图差热分析衍射强度

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基于多尺度特征增强的合成孔径光学图像复原

物理学报 2024年第6期73卷 209-221页

作者：张银胜童俊毅陈戈单梦姣王硕洋单慧琳无锡学院江苏省集成电路可靠性技术及检测系统工程研究中心无锡214105 南京信息工程大学电子信息工程学院南京210044

受物理孔径大小和光线散射等影响,合成孔径光学系统成像因通光面积不足和相位失真而出现降质模糊.传统合成孔径光学系统成像复原算法对噪声敏感,过于依赖退化模型,自适应性差.对此提出一种基于生成对抗网络的光学图像复原方法,采用U-Ne... 详细信息

受物理孔径大小和光线散射等影响,合成孔径光学系统成像因通光面积不足和相位失真而出现降质模糊.传统合成孔径光学系统成像复原算法对噪声敏感,过于依赖退化模型,自适应性差.对此提出一种基于生成对抗网络的光学图像复原方法,采用U-Net结构获取图像多级尺度特征,利用基于自注意力的混合域注意力提高网络在空间、通道上的特征提取能力,构造多尺度特征融合模块和特征增强模块,融合不同尺度特征间的信息,优化了编解码层的信息交互方式,增强了整体网络对原始图像真实结构的关注力,避免在复原过程中被振铃现象产生的伪影干扰.实验结果表明,与其他现有方法相比,该方法在峰值信噪比、结构相似性和感知相似度评估指标上分别提高了1.51%,4.42%和5.22%,有效解决合成孔径光学系统成像结果模糊退化的问题.

关键词：图像处理合成孔径多尺度特征融合

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芳基乙炔聚合物固化反应动力学和结构表征

华东理工大学学报（自然科学版） 2001年第2期27卷 161-164页

作者：丁学文齐会民庄元其王俊徐柏华焦扬声华东理工大学功能复合材料研究室上海200237

应用 DSC和 FTIR分析技术 ,研究了芳基乙炔聚合物的固化反应动力学和固化反应过程中的结构变化。结果表明 :芳基乙炔聚合物固化过程中主要形成顺式共轭多烯结构。芳基乙炔聚合物的固化反应活化能为 1 0 8.6～ 1 1 9.7k J/mol,单体结构... 详细信息

应用 DSC和 FTIR分析技术 ,研究了芳基乙炔聚合物的固化反应动力学和固化反应过程中的结构变化。结果表明 :芳基乙炔聚合物固化过程中主要形成顺式共轭多烯结构。芳基乙炔聚合物的固化反应活化能为 1 0 8.6～ 1 1 9.7k J/mol,单体结构对聚合物的固化反应速率有明显影响 ,聚 1 ,4-二乙炔基苯 ( p- DEB)的固化反应速率比聚 1 ,3-二乙炔基苯 ( m- DEB)

关键词：芳基乙炔聚合物多烯结构固化反应动力学端快基聚合物二乙炔基苯碳/碳复合材料

Study on the expression and prognostic relationship of MYL6B in liver cancer based on bioinformatics

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World Journal of Clinical Oncology 2024年第9期15卷 1188-1197页

作者： Hai-Bing Lv Qing-Yun Wu Yu-jiao Zhang sheng-Wei Quan Ning Ma Yu-Qing Dai Yan Sun Department of General Surgery Beidahuang Group General HospitalHarbin 150000Heilongjiang ProvinceChina Department of General Surgery Xianning Central HospitalXianning 437000Hubei ProvinceChina Department of Medical oncology Beidahuang Group General HospitalHarbin 150000Heilongjiang ProvinceChina Department of General Surgery Daqing Oilfield General HospitalDaqing 163000Heilongjiang ProvinceChina College of Clinical Medicine Bengbu Medical UniversityBengbu 233000Anhui ProvinceChina Department of General Surgery Second Affiliated Hospital of Harbin Medical UniversityHarbin 150000Heilongjiang ProvinceChina

BACKGROUND Primary liver cancer is a prevalent and deadly cancer *** treatment advances,prognosis remains poor,with high recurrence *** detection is crucial but challenging due to the disease’s insidious *** proteins play significant roles in cancer development,influencing cell migration,invasion,and tumor ***6B,a myosin light chain,is involved in various cellular processes and has been associated with poor prognosis in colorectal adenocarcinoma and potential as a biomarker in breast *** To investigate the expression of MYL6B in liver hepatocellular carcinoma(LIHC)and its impact on prognosis and potential mechanisms of action using bioinformatics *** The expression of MYL6B in pan-cancer and normal tissues was analyzed using the gene expression profiling interactive analysis 2 and tumor immune estimation resource *** expression level of MYL6B in LIHC tissues and its relationship with prognosis were analyzed,immunohistochemical analysis of MYL6B and its effect on immune cell infiltration,and the protein network were further *** MYL6B was highly expressed in diffuse large b-cell lymphoma,LIHC,pancreatic adenocarcinoma,skin cutaneous melanoma,thymoma,uterine corpus endometrial carcinoma,uterine carcinosarcoma,and lowly expressed in kidney chromophobe,acute myeloid leukemia,testicular germ cell *** expression level of MYL6B was significantly different between cancer and normal *** had a significant impact on both overall survival and disease-free ***6B is highly expressed in hepatocellular carcinoma and its expression level increases with cancer *** MYL6B expression is associated with poor prognosis in terms of overall survival and recurrence-free *** immunohistochemical level of MYL6B is high in hepatocellular carcinoma tissues,and MYL6B has a high level of immune infiltration *** protein network analysis,MYL6B is correlated with MYL2

关键词： MYL6B Liver cancer Bioinformatics Prognosis Expression

Hydrogen-rich surface of MoC catalysts for efficient CO_(2) hydrogenation induced by a coupled hydrogen donator

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Nano Research 2024年第8期17卷 7762-7767页

作者： Dong Xu Si-Yuan Xia Qi-Yuan Li Jie-sheng Chen Xin-Hao Li School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesShanghai Jiao Tong UniversityShanghai 200240China

Direct CO_(2) hydrogenation offers an important strategy for promoting the global carbon balance,but high thermodynamic and kinetic stability of CO_(2) has restricted its applicability to only a handful of industrial ***,we introduce a proof-of-concept application of the electron-rich Pt surface to promote hydrogen donation for electron-rich MoC particles acting as hydrogen acceptors,thereby constructing hydrogen-rich surface of MoC active ***,the formed hydrogen-rich and electronrich surface could greatly decrease reaction activation energy to boost the efficient CO_(2) hydrogenation into formic acid over the MoC *** optimized MoC@NC/Pt-0.1(NC:nitrogen-doped carbon)catalyst exhibits a high turnover frequency(TOF)value of 1.2 h^(−1) at a lower temperature of 60℃and a TOF of 24.2 h^(−1) under standard reaction conditions widely used in the literature,exceeding 7 times of MoC@NC catalyst and surpassing the benchmark classical non-noble metal active center-based heterogeneous catalyst.

关键词： electron-rich Pt nanoparticles hydrogen donation hydrogen-rich MoC nanoparticles CO_(2) hydrogenation formic acid

Féeton(B-L gauge boson)dark matter for the 511-keV gamma-ray excess and the prediction of low-energy neutrino flux

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Chinese Physics C 2024年第8期48卷 76-82页

作者： Jie sheng Yu Cheng Weikang Lin Tsutomu T.Yanagida Tsung-Dao Lee Institute&School of Physics and Astronomy Shanghai Jiao Tong UniversityChina Key Laboratory for Particle Astrophysics and Cosmology(MOE)&Shanghai Key Laboratory for Particle Physics and Cosmology Shanghai Jiao Tong UniversityShanghai 200240China South-Western Institute For Astronomy Research Yunnan UniversityKunming 650500China Kavli IPMU(WPI) UTIASUniversity of TokyoKashiwa277-8583Japan

The féeton is the gauge boson of the U(1)_(B−L) gauge *** the gauge coupling constant is extremely small,the féeton becomes a candidate for dark *** show that its decay to a pair of an electron and a positron explains the observed Galactic 511-keV gamma-ray excess in a consistent *** féeton dark matter decays mainly into pairs neutrino and *** low-energy experiments with improved directional capability will enable capturing these neutrino *** seesaw-motivated parameter space predicts a relatively short féeton lifetime that is comparable to the current cosmological constraint.

关键词： feeton 511-keV gamma-ray excess low-energy neutrino