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Coarse grained molecular dynamics and theoretical studies of carbon nanotubes entering cell membrane

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Acta Mechanica Sinica 2008年第2期24卷 161-169页

作者： Xinghua Shi yong kong H. Gao Division of Engineering Brown University 182 Hope Street Providence RI 02912 USA ICx Radiation GmbH Koelnerstrasse 99 42651 Solingen Germany

Motivated by recent experimental observations that carbon nanotubes （CNT） can enter animal cells, here we conduct coarse grained molecular dynamics and theoretical studies of the intrinsic interaction mechanisms between CNT＇s and lipid bilayer. The results indicate that CNT-cell interaction is dominated by van der Waals and hydrophobic forces, and that CNT＇s with sufficiently small radii can directly pierce through cell membrane while larger tubes tend to enter cell via a wrapping mechanism. Theoretical models are proposed to explain the observed size effect in transition of entry mechanisms.

关键词： Molecular dynamics Carbon nanotube Cell membrane Interaction mechanism

Molecular dynamics simulation of peeling a DNA molecule on substrate

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Acta Mechanica Sinica 2005年第3期21卷 249-256页

作者： Xinghua Shi yong kong Yapu Zhao Huajian Gao Max-Planck Institut für Metallforschung Heisenbergstr. 3 D-70569 Stuttgart Germany State Key Laboratory of Nonlinear Mechanics (LNM) Institute of Mechanics Chinese Academy of Sciences. Beijing 100080 China

Molecular dynamics （MD） simulations are performed to study adhesion and peeling of a short fragment of single strand DNA （ssDNA） molecule from a graphite surface. The critical peel-off force is found to depend on both the peeling angle and the elasticity of ssDNA. For the short ssDNA strand under investigation, we show that the simulation results can be explained by a continuum model of an adhesive elastic band on substrate. The analysis suggests that it is often the peak value, rather than the mean value, of adhesion energy which determines the peeling of a nanoscale material.

关键词： Molecular dynamics simulation DNA Adhesion Peeling

高校图书馆数字学术服务质量评价模型构建及应用研究

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图书馆学研究 2024年第6期 61-69页

作者：吴运明孔勇董同强周凯曲阜师范大学教育学院曲阜师范大学传媒学院齐鲁师范学院

高校图书馆数字学术服务质量的量化评估,能够准确找到服务薄弱环节,为服务内容与形式的创新提供依据。文章引入服务质量差距模型,结合高校图书馆数字学术服务的特点,兼顾科研全生命周期过程,提炼影响服务质量的关键要素,构建包含机构支... 详细信息

高校图书馆数字学术服务质量的量化评估,能够准确找到服务薄弱环节,为服务内容与形式的创新提供依据。文章引入服务质量差距模型,结合高校图书馆数字学术服务的特点,兼顾科研全生命周期过程,提炼影响服务质量的关键要素,构建包含机构支持能力、数据资源保障能力、过程管理服务能力、技术支撑能力、创新反馈能力的感知维度指标体系,并进一步采用重要性绩效分析方法,对T大学图书馆数字学术服务质量进行评价,以期为高校图书馆数字学术服务质量持续改进探寻路径。

关键词：数字学术服务服务质量差距模型服务质量评价重要性-绩效分析方法

Efficient degradation of orange II by ZnMn2O4 in a novel photo-chemical catalysis system

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Frontiers of Chemical Science and Engineering 2020年第6期14卷 956-966页

作者： Qingzhuo Ni Hao Cheng Jianfeng Ma yong kong Sridhar Komarneni School of Environmental and Safety Engineering Changzhou UniversityChangzhou 213164China Guangxi Key Laboratory of Green Processing of Sugar Resources College of Biological and Chemical EngineeringGuangxi Science University of and TechnologyLiuzhou 545006China Jiangsu Key Laboratory of Oil-Gas Storage and Transportation Technology Changzhou UniversityChangzhou 213164China Department of Ecosystem Science and Management and Materials Research Institute The Pennsylvania State UniversityUniversity ParkPA 16802USA

A ZnMn2O4 catalyst has been synthesized via a sucrose-aided combustion method and characterized by various analytical techniques.It is composed of numerous nanoparticles(15-110 nm)assembled into a porous structure with a specific surface area(SSA)o f 19.1 m^2.g^-1.Its catalytic activity has been investigated for the degradation of orange II dye using three different systems,i.e.,the photocatalysis system with visible light,the chemocatalysis system with bisulfite,and the photochemical catalysis system with both visible light and bisulfite.The last system exhibits the maximum degradation efficiency of 90%,much higher than the photocatalysis system(15%)and the chemocatalysis system(67%).The recycling experiments indicate that the ZnMn204 catalyst has high stability and reusability and is thus a green and eximious catalyst.Furthermore,the potential degradation mechanisms applicable to the three systems are discussed with relevant theoretical analysis and scavenging experiments for radicals.The active species such as Mn(III),o2^-,H^+,eaq,So4^- and Ho^-are proposed to be responsible for the excellent degradation results in the photo-chemical catalysis system with the ZnMn2o4 catalyst.

关键词： ZnMn2O4 photo-chemical catalysis bisulfite dye degradation

雷公藤红素通过调控ATF4/caspase-3/GSDME信号通路促进肝癌细胞焦亡

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中国药理学通报 2024年第2期40卷 299-307页

作者：李端王永辉周静张乐孔永红黄淮学院直属附属驻马店市中心医院药学部河南驻马店463000 苏州大学药学院药理学系江苏苏州215123 黄淮学院化学与制药工程学院河南驻马店463003

目的探究雷公藤红素(tripterine,TRI)抑制肝癌细胞(hepatocellular carcinoma,HCC)进展的新机制。方法利用不同浓度(0、0.5、2和8μmol·L-1)TRI作用于肝癌细胞,然后利用CCK-8、细胞克隆、Transwell和蛋白免疫印迹等实验方法评估细胞表... 详细信息

目的探究雷公藤红素(tripterine,TRI)抑制肝癌细胞(hepatocellular carcinoma,HCC)进展的新机制。方法利用不同浓度(0、0.5、2和8μmol·L-1)TRI作用于肝癌细胞,然后利用CCK-8、细胞克隆、Transwell和蛋白免疫印迹等实验方法评估细胞表型和可能机制;再利用siRNA将靶基因GSDME进行干扰,确定GSDME的作用;最后使用移植肿瘤模型验证TRI在体内抑制HCC细胞的生长的机制。结果TRI可抑制HCC细胞增殖、克隆和侵袭,促进细胞焦亡。免疫印迹结果显示,TRI处理后肝细胞癌HepG2或Hepa1-6中GSDME表达均上调,同时cleaved caspase-3和PARP也明显升高。敲除GSDME后可部分逆转TRI诱导的细胞焦亡。同时GSDME敲低后的细胞具有更强的克隆和迁移能力,且与单独的TRI治疗组相比,细胞凋亡率降低。在体内实验中,TRI抑制可HCC肿瘤生长,TRI+siGSDME组小鼠肿瘤生长速度比单独TRI治疗组快。此外,TRI刺激后HepG2和Hepa1-6细胞中p-eIF2a、ATF4均升高。免疫荧光结果显示,TRI刺激后HepG2和Hepa1-6细胞中ATF4阳性细胞数呈剂量依赖性增加。结论TRI抑制肝癌细胞生长和侵袭可能与其调控ATF4/caspase-3/GSDME信号通路促进肝癌细胞焦亡有关。

关键词：肝癌细胞细胞焦亡雷公藤红素 GSDME ATF4 caspase3

The effect of fasting plasma glucose on in-hospital mortality after acute myocardial infarction in patients with and without diabetes:findings from a prospective,nationwide,and multicenter registry

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Journal of Geriatric Cardiology 2024年第5期21卷 523-533页

作者： Rui FU Ying-Xuan ZHU kong-yong CUI Jin-Gang YANG Hai-Yan XU Dong YIN Wei-Hua SONG Hong-Jian WANG Cheng-Gang ZHU Lei FENG Wei WU Kai-HongCHEN Yan-Yan ZHAO Ye LU Ke-Fei DOU Yue-Jin YANG on behalf of the CAMI Registry Investigators Cardiometabolic Medicine Center Fuwai HospitalNational Center for Cardiovascular DiseasesState Key Laboratory of Cardiovascular DiseaseNational Clinical Research Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Medical Research&Biometrics Center Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Coronary Heart Disease Center Fuwai HospitalNational Center for Cardiovascular DiseasesState Key Laboratory of Cardiovascular DiseaseNational Clinical Research Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Department of Cardiology Guangzhou Traditional Chinese Medical College First Affiliated HospitalGuangdong ProvinceChina Department of Cardiology Longyan Hospital First HospitalFujian ProvinceChina 不详

OBJECTIVES To evaluate the predictive value of fasting plasma glucose(FPG)for in-hospital mortality in patients with acute myocardial infarction(AMI)with different glucose metabolism status.METHODS We selected 5,308 participants with AMI from the prospective,nationwide,multicenter CAMI registry,of which 2,081 were diabetic and 3,227 were nondiabetic.Patients were divided into high FPG and low FPG groups according to the optim-al cutoff values of FPG to predict in-hospital mortality for diabetic and nondiabetic cohorts,respectively.The primary endpoint was in-hospital mortality.RESULTS Overall,94 diabetic patients(4.5%)and 131 nondiabetic patients(4.1%)died during hospitalization,and the optimal FPG thresholds for predicting in-hospital death of the two cohorts were 13.2 mmol/L and 6.4 mmol/L,respectively.Compared with individuals who had low FPG,those with high FPG were significantly associated with higher in-hospital mortality in diabet-ic cohort(10.1%vs.2.8%;odds ratio[OR]=3.862,95%confidence interval[CI]:2.542-5.869)and nondiabetic cohort(7.4%vs.1.7%;HR=4.542,95%CI:3.041-6.782).After adjusting the potential confounders,this significant association was not changed.Further-more,FPG as a continuous variable was positively associated with in-hospital mortality in single-variable and multivariable models regardless of diabetic status.Adding FPG to the original model showed a significant improvement in C-statistic and net reclassification in diabetic and nondiabetic cohorts.CONCLUSIONS This large-scale registry indicated that there is a strong positive association between FPG and in-hospital mor-tality in AMI patients with and without diabetes.FPG might be useful to stratify patients with AMI.

关键词： patients fasting infarction

Shape-tailorable amine grafted silica aerogel microsphere for CO_(2) capture

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Green Chemical Engineering 2020年第2期1卷 140-146页

作者： Xing Jiang Jian Ren yong kong Zhiyang Zhao Xiaodong Shen Maohong Fan College of Materials Science and Engineering Nanjing Tech UniversityNanjing210009PR China Department of Chemical and Petroleum Engineering University of WyomingLaramieWY82071USA Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites Nanjing210009PR China School of Civil and Environmental Engineering Georgia Institute of TechnologyAtlantaGA30332USA Suqian Advanced Materials Industry Technology Innovation Center of Nanjing Tech University Suqian223800PR China

The purpose of this study was to prepare a proof-of-concept CO_(2) adsorbing material based on a new amine grafted silica aerogel microsphere(AGSAM)that could be used on both fixed and fluidized beds.A low-cost water glass and environment-friendly water were used as precursor and solvent of the silica aerogel,respectively.The silica aerogel microsphere(SAM)was prepared by dropping the siliceous solution into hot oil bath.The effect of the pH value of the siliceous solution,stirring speed and stirring paddle position on the sphericity and size of the SAM was investigated.The SAM with good sphericity was obtained when the pH value was 5.69–5.79.The mean diameter of the SAM decreased from 5 to 1 mm when the stirring speed increased from 1000 to 2000 rpm.The SAM with excellent sphericity was prepared when the paddle was placed on the top of the oil bath.When the paddle was placed at the middle and bottom of the oil bath,some liquid drops aggregated together and formed large aggregations.AGSAM was obtained by grafting the amine groups onto the framework of the silica gel microsphere.The CO2 adsorption capacity of the AGSAM was 1.04 mmol g^(-1) with 1%CO2 at 300 mL min^(-1).The AGSAM with 4,3.2,2 and 1 mm in diameters had the fluidizing velocities of 0.531,0.425,0.265 and 0.159 m s^(-1),respectively.The AGSAM with different sizes met different fluidizing conditions.

关键词： Silica aerogel Microsphere Amine grafting CO_(2)adsorption

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数字全息显微信号项频谱定位及干扰项抑制

光学技术 2024年第3期50卷 277-287页

作者：张贺孔勇吴慧慧廖后章陈杰上海工程技术大学电子电气工程学院控制工程系上海201620 上海理工大学光电信息与计算机工程学院上海200093

在离轴数字全息显微和非相干光成像研究中,空间频域滤波是重建目标物体的振幅和相位信息的关键步骤。信号项频谱选取及中心定位对滤波后重建相位的质量有着极大影响,即使像素级的微小差异也会导致重建相位的严重失真。为了解决这个问题... 详细信息

在离轴数字全息显微和非相干光成像研究中,空间频域滤波是重建目标物体的振幅和相位信息的关键步骤。信号项频谱选取及中心定位对滤波后重建相位的质量有着极大影响,即使像素级的微小差异也会导致重建相位的严重失真。为了解决这个问题,文章提出了一种数字全息显微信号项频谱定位及干扰项抑制的方法。方法根据全息图频谱的直方图分布特性,自适应确定滤波形状和大小,同时,采用质心法来快速准确的确定信号项频谱的中心,并在频域中运用形态学处理来消除信号项频谱周围的干扰项。实现了信号项频谱自适应滤波,从而提高了相位重建的质量。文章使用二维山形图模拟相位进行了仿真验证,并搭建光路拍摄USAF1951标定板上的数字区域和洋葱表皮细胞进行了实验验证。仿真和实验结果表明,算法可以实现高质量的相位重建,并对干扰项进行抑制,提高了离轴数字全息显微系统的成像质量。

关键词：数字全息频谱滤波频谱中心定位干扰项抑制相位重建

基于改进的非局部均值滤波对数字全息散斑的抑制

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光学技术 2024年第2期50卷 135-141页

作者：吴慧慧孔勇张贺廖后章童晓凡上海工程技术大学电子电气工程学院上海200000

为了降低数字全息术领域中散斑噪声对重建相质量的影响,提出了一种改进的非局部均值滤波对数字全息散斑抑制的方法。方法使用统计学中的皮尔逊相关系数来改进非局部均值滤波中子块相似度的度量,并根据相似度系数的大小分为两个不同强度... 详细信息

为了降低数字全息术领域中散斑噪声对重建相质量的影响,提出了一种改进的非局部均值滤波对数字全息散斑抑制的方法。方法使用统计学中的皮尔逊相关系数来改进非局部均值滤波中子块相似度的度量,并根据相似度系数的大小分为两个不同强度域,对其赋予不同的值,使灰度图去噪的对比成度更加强烈。方法不仅能更进一步的滤除散斑,还能更好的保持图像的边缘信息,可以解决传统非局部均值滤波中出现的图像过度滤波问题。实验结果表明,改进后的非局部均值滤波能够有效地降低数字全息图像中的散斑噪声,提高图像的质量和清晰度,与多数传统的数字图像处理方法相比性能更好。

关键词：数字全息散斑抑制非局部均值滤波皮尔逊相关系数