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槲皮素通过抑制p38 MAPK/NOX4信号通路减轻H_(2)O_(2)诱导的人子宫内膜基质细胞氧化应激损伤

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四川大学学报（医学版） 2024年第3期55卷 552-558页

作者：陈秀楠王瑞琦单红英周平李蓉北京大学第三医院生殖医学中心北京100191

目的探讨槲皮素对过氧化氢(hydrogen peroxide, H_(2)O_(2))诱导人子宫内膜基质细胞(human endometrial stromal cells, HESCs)损伤的保护作用及其可能的作用机制。方法体外培养HESCs,加入不同浓度的槲皮素(0、10、20和40μmol/L)作用... 详细信息

目的探讨槲皮素对过氧化氢(hydrogen peroxide, H_(2)O_(2))诱导人子宫内膜基质细胞(human endometrial stromal cells, HESCs)损伤的保护作用及其可能的作用机制。方法体外培养HESCs,加入不同浓度的槲皮素(0、10、20和40μmol/L)作用24 h,验证给予不同剂量的槲皮素对正常子宫内膜细胞没有毒性,随后采用250μmol/L H_(2)O_(2)孵育细胞12 h,建立H_(2)O_(2)诱导的HESCs损伤模型。槲皮素预处理24 h,H_(2)O_(2)刺激HESCs后,CCK-8检测细胞活力,筛选有效的干预剂量,随后将HESCs分为空白组、H_(2)O_(2)模型组、H_(2)O_(2)+槲皮素组,采用DCFH-DA荧光探针检测细胞内活性氧(reactive oxygen species, ROS)水平;AnnexinⅤ/PI双染,流式细胞术检测槲皮素对H_(2)O_(2)诱导HESCs凋亡的影响;JC-1染色法检测细胞线粒体膜电位;Western blot检测相关蛋白NADPH氧化酶4(NADPH oxidase 4, NOX4)、p38丝裂原活化蛋白激酶(p38 mitogen-activated protein kinase, p38 MAPK)及磷酸化p38 MAPK(p-p38 MAPK)表达。结果根据CCK-8实验结果,选择槲皮素20μmol/L为有效干预剂量。ROS检测显示,与空白组相比,H_(2)O_(2)模型组ROS的平均荧光强度升高(P<0.01),而与H_(2)O_(2)模型组相比槲皮素处理下调了ROS的平均荧光强度,减轻了氧化损伤(P<0.05)。细胞凋亡检测结果显示,H_(2)O_(2)模型组细胞凋亡率较空白组增加(P<0.01),而与槲皮素共同作用则逆转了细胞凋亡率的增加(P<0.05)。JC-1染色检测线粒体膜电位变化情况显示,与空白组相比,H_(2)O_(2)诱导所致的线粒体膜电位降低的细胞比例增加(P<0.01),而槲皮素处理后线粒体膜电位降低的细胞比例低于H_(2)O_(2)模型组(P<0.05)。Western blot结果显示,与空白组相比,H_(2)O_(2)模型组NOX4蛋白、p-p38 MAPK蛋白相对表达量升高(P<0.05);而加入槲皮素后,与H_(2)O_(2)模型组相比,NOX4蛋白、p-p38 MAPK蛋白相对表达量降低(P<0.05)。结论槲皮素预处理对H_(2)O_(2)诱导的HESCs氧化损伤具有保护作用,其机制可能是减少ROS过量累积以及抑制p38 MAPK/NOX4信号通路。

关键词：槲皮素子宫内膜基质细胞氧化应激细胞凋亡活性氧

基于多种路用环境下对布敦岩沥青混凝土低温开裂特性的分析

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材料科学与工程学报 2023年第3期41卷 514-521页

作者：闫景晨陈秀楠马炎沛内蒙古工业大学土木工程学院内蒙古呼和浩特010051 中国第七工程局有限公司西南分公司工程部重庆400000

本研究通过冻断试验和三点弯试验分别对五种路用环境下的布敦岩沥青混凝土、基质沥青混凝土和SBS改性沥青混凝土进行低温抗裂对比分析,并通过数值模拟试验从试件损伤和能量耗散两方面进行布敦岩沥青混凝土低温开裂机理研究。结果表明:... 详细信息

本研究通过冻断试验和三点弯试验分别对五种路用环境下的布敦岩沥青混凝土、基质沥青混凝土和SBS改性沥青混凝土进行低温抗裂对比分析,并通过数值模拟试验从试件损伤和能量耗散两方面进行布敦岩沥青混凝土低温开裂机理研究。结果表明:布敦岩沥青混凝土具有比其他两种沥青混凝土更高的转化点温度,但在冻结时的断裂强度和冻断温度略低于SBS改性沥青混凝土,而优于基质沥青混凝土。在低温下,布敦岩沥青混凝土的应变能密度大于基质沥青混凝土,略低于SBS改性沥青混凝土,这表明在基质沥青中掺加适量的布敦岩沥青可以提高其抗温缩开裂性能。另外,布敦岩沥青混凝土在低温条件下弯曲破坏过程中只有少部分塑性变形,应变能以塑性变形的方式耗散较少,主要是通过脆性破坏产生的裂隙耗散。

关键词：布敦岩沥青混凝土低温开裂应变能密度损伤变量离散元

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基于壳聚糖二氧化碳智能材料

化学进展 2020年第4期32卷 417-422页

作者：闻静李禹红王莉陈秀楠曹旗何乃普兰州交通大学化学与生物工程学院兰州730070

二氧化碳(CO2)捕获以及转化是控制大气中二氧化碳含量和有效利用的主要策略。CO2响应型聚合物以含有胺基的烯类单体为主要原料,通过接枝聚合或与其他功能分子复合来改善其对CO2的响应以及捕获性能。其中,天然高分子(如多糖、蛋白质等)... 详细信息

二氧化碳(CO2)捕获以及转化是控制大气中二氧化碳含量和有效利用的主要策略。CO2响应型聚合物以含有胺基的烯类单体为主要原料,通过接枝聚合或与其他功能分子复合来改善其对CO2的响应以及捕获性能。其中,天然高分子(如多糖、蛋白质等)具有资源丰富、无毒、可降解和良好的生物相容性等优点,是制备环境友好高分子材料的最佳选择。同时,壳聚糖含有大量的伯胺,在制备基于胺基的具有CO2响应以及捕获性能的智能复合材料中具有潜在优势。本文首先介绍了CO2响应聚合物和壳聚糖的特点,进一步归纳了近年来基于壳聚糖的CO2响应高分子以及捕获材料的最新研究进展,并对这类复合材料的设计及其应用前景进行了展望。

关键词：壳聚糖响应型高分子二氧化碳捕获智能材料

Thermodynamic and kinetic mechanism of phase transformation of levofloxacin hydrochloride

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Particuology 2022年第7期20卷 59-70页

作者： Han Liu xiunan Zhang Ting Wang Xin Huang Kui chen Na Wang Shanshan Yu Yuyuan Dong Hongxun Hao National Engineering Research Center for Industrial Crystallization Technology School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China School of Chemical Engineering and Technology Hainan UniversityHaikou 570208China

In this work,thermodynamic and kinetic factors that affect formation and phase transformation process of different solid forms of levofloxacin hydrochloride were investigated in *** vapor sorption experiments(DVS)and varying temperature-powder X-ray diffraction(VT-PXRD)experiments were carried out to study moisture-dependent stability,thermal stability as well as the transformation process between Form I and Form *** water activities of levofloxacin hydrochloride were determined in temperature range of 5.0–45.0°*** spectroscopy was applied to in situ monitor the temperature-induced phase transformation and the hydration process of levofloxacin hydrochloride,and one possible mechanism consisting of multiple chemical equilibria was proposed to analyze the effect of thermodynamic and kinetic factors on the formation and transformation of different solid *** show that the anhydrate,Form II would transform to the monohydrate,Form I more easily with the increasing water *** the transition point moves toward higher water contents as the temperature *** results suggested that,except for thermodynamic factors,kinetic factors also play an essential role in controlling the solid forms of polymorphic compounds.

关键词： Levofloxacin hydrochloride Crystallization Phase transformation Hydrate

Rapid detection to long ship wake in synthetic aperture radar satellite imagery

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Journal of Oceanology and Limnology 2019年第5期37卷 1523-1532页

作者： chen Peng LI xiunan ZHENG Gang Second Institute of Oceanography Ministry of Natural Resources

The maritime administrative department employs synthetic aperture radar (SAR) satellite remote sensing technology to obtain evidence of illegal discharge of ships. If the ship is discharged during navigation, it forms a long dark wake on the SAR image due to the suppression of the Bragg wave by the oil fi lm. This study investigates key techniques for rapid detection of long ship wakes, thereby providing law enforcement agencies with candidate ships for possible discharge. This paper presents a rapid long ship wake detection method that uses satellite imaging parameters and the axial direction of the ship in images to determine the potential detection area of the wake. Then, the threshold of long ship wake detection is determined using statistical analysis, the area is binarized, and isolated points are removed using a morphological filter operator. The method was tested with ENVISAT Synthetic Aperture Radar and GF-3 SAR data, and results showed that the method was eff ective, and the overall accuracy of the decision reaches 71%. We present two innovations;one is a method that draws a Doppler shift curve, and uses the SAR imaging parameters to determine the detection area of the long wake to achieve rapid detection and reduce the image detection area. The other is where a classical linear fitting method is used to quickly and accurately determine whether the detected dark area is a long ship wake and realizes the twisted long ship wake detection caused by the sea surface flow field, which is otherwise diffi cult to detect by the traditional Radon and Hough transform methods. This method has good suppression performance for the dark spot false alarm formed by low speed wind region or upward flow. The method is developed for maritime ship monitoring system and will promote the operational application of maritime ship monitoring system.

关键词： marine pollution illegal discharge linear fi t oil spill synthetic aperture radar (SAR) long ship wake

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不同流出率对黄瓜椰糠栽培的影响

中国瓜菜 2022年第4期35卷 70-74页

作者：钟泽许光利程果陈秀楠杨云云李文虎中国农业科学院郑州果树研究所郑州450009 江苏绿港现代农业发展股份有限公司江苏宿迁223800

为探索玻璃温室椰糠基质栽培条件下灌溉量对黄瓜生长和产量的影响,设置了15%(T1)、20%(T2)、25%(T3)和30%(T4)4个流出率进行试验。结果显示,随着流出率的增加,流出液的EC、pH更接近灌溉液的EC、pH,大量元素和中量元素的含量没有规律性... 详细信息

为探索玻璃温室椰糠基质栽培条件下灌溉量对黄瓜生长和产量的影响,设置了15%(T1)、20%(T2)、25%(T3)和30%(T4)4个流出率进行试验。结果显示,随着流出率的增加,流出液的EC、pH更接近灌溉液的EC、pH,大量元素和中量元素的含量没有规律性的变化,但钠和氯的含量呈递减趋势;流出率从T1增至T3时,蔓长和叶片数随之增加,其中T3与T1相比分别增加0.45 m和3.0片叶,达5%显著差异水平。超过T3后,T4的蔓长和叶数反而减少;尽管T1的单株产量3.39 kg·株^(-1)最高,比最低T2和T4的3.16 kg·株^(-1)高出0.23 kg·株^(-1),但没有达到显著差异水平;肥料生产力与流出率呈负相关,T1最高31.47 kg·kg^(-1),比最低T4的21.29 kg·kg^(-1)显著高10.18 kg·kg^(-1),超出47.82%。综上所述,当灌溉水中钠离子含量(ρ)不超过60 mg·L^(-1)时,15%流出率可作为黄瓜椰糠栽培的适宜灌溉量指标。

关键词：黄瓜温室椰糠栽培流出率灌溉量肥料生产力

Continuous mechanical tuning of plasmonic nanoassemblies for tunable and selective SERS platforms

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Nano Research 2021年第1期14卷 275-284页

作者： xiunan Yan Qing chen Qun Song Ziyu Huo Ning Zhang Mingming Ma CAS Key Laboratory of Soft Matter Chemistry Hefei National Laboratory for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefei 230026China Department of Biological and Environmental Engineering Hefei UniversityHefei 230601China

The continuous tuning of plasmonic nanoassembly's structure is the key to manipulate their optical and catalytic ***,we report a strategy of using macroscopic deformation to continuously tune the structure and optical activity of massive plasmonic nanoassemblies that are embedded in elastic polymer *** gold nanoparticles(Au NPs)are assembled to nanochains(Au NCs)with defined length and further embedded into polyvinylpyrrolidone(PVP)*** nanostructure and plasmonic properties of massive Au NCs in this Au NCs-PVP film can be simultaneously and continuously tuned,simply by reversible mechanical deformation of this elastic *** this way,the surface-enhanced Raman scattering(SERS)enhancement factor of this film as a SERS substrate can be mechanically modulated in the range of 10^(0)to 6.8×10^(7).Meanwhile,the PVP matrix also serves as a selective diffusion barrier to eliminate the fluorescence interference of large biomolecules,which enables the Au NCs-PVP film as a convenient SER S substrate for quick and direct analysis of small molecule analytes in biological samples and food,avoiding the complicate and time-consuming sample pretreatment process.

关键词： surface-enhanced Raman scattering(SERS) plasmonic hotspots nanoassembly gold nanoparticles bioanalysis

Compression induced crystal-to-glass transition in soft colloidal solids

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National Science Open 2023年第3期2卷 55-63页

作者： Li chen xiunan Yang Mingcheng Yang chenhong Wang Ke chen Beijing National Laboratory for Condensed Matter Physics and Key Laboratory of Soft Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Bejing 100049China Cygnus Biosciences Co. LtdBeijing 100176China Beijing Tide Pharmaceutical Co LtdBeijing 100176China Songshan Lake Materials Laboratory Dongguan 523808China

Using colloidal particles with diﬀerent thermosensitivities,we observe the transition from a crystalline solid to a dis-ordered glass by tuning the size mismatch of the constituent particles in quasi-two-dimensional conﬁ*** transition is clearly identiﬁable by the correlation functions of the orientational order parameters and its ***ﬀerent from typical order-to-disorder transitions such as melting,where the underlying mechanism involves the diﬀusion of defects,the disordered phase in the crystal-to-glass transition grows via a nucleation *** disordered clusters grow in size as the particle mismatch increases,and eventually percolate the whole system,which signiﬁes the qualitative change from an ordered crystal to a disordered glass.

关键词： crystal-to-glass transtion percolation colloidal solids

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去除重金属的净水纳米吸附剂研究综述

科技资讯 2020年第31期18卷 69-73页

作者：沈德朝陈秀楠李惠颖张好迪邱爱中郑州师范学院河南郑州450044

纳米吸附剂具有高化学活性,吸附能力的原子大都在纳米材料表面。该文综述了纳米材料作为纳米吸附剂的潜力及其研究进展,在污水中处理重金属的应用;从吸附去除材料的角度揭示了纳米复合材料的吸附机理、吸附环境、吸附效果等,评价了它们... 详细信息

纳米吸附剂具有高化学活性,吸附能力的原子大都在纳米材料表面。该文综述了纳米材料作为纳米吸附剂的潜力及其研究进展,在污水中处理重金属的应用;从吸附去除材料的角度揭示了纳米复合材料的吸附机理、吸附环境、吸附效果等,评价了它们在净水方面的优缺点。讨论了纳米材料对公众健康的影响以及在促进环境可持续性方面的发展方向。

关键词：纳米复合材料吸附剂吸附机理重金属