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Science China(Technological Sciences) 2024年第4期67卷 1160-1169页

作者： NIU QingJing GAO ShuHui ZHU KongYing REN LiXia yuan xiaoyan School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin 300350China Analysis and Measurement Center Tianjin UniversityTianjin 300072China

Cryopreservation plays an essential role in biobanking and cell therapy,but the physiological toxicity of traditional cryoprotectants such as glycerol and dimethyl sulfoxide(DMSO)has raised safety issues for biomedical ***,a nonreducing disaccharide that accumulates in desiccation-or cold-tolerant organisms,has been considered as a biocompatible ***,a naturally occurring membrane-active cationic peptide,melittin,was utilized to facilitate membraneimpermeable trehalose entry into cells for effective cell ***(ethylene glycol)and poly(vinyl pyrrolidone)were applied as macromolecular protectants to improve the stabilization of cell *** the optimal protocol,the postthaw recovery of human red blood cells in freezing bags at a hematocrit of~50%could achieve 82.9%with favorable cell morphologies and physiological ***,the cryosurvival of L929 fibroblasts reached 84.3%compared to the conventional method using 10%(v/v)*** short,this work by using trehalose and melittin provides a biocompatible solvent-free approach for long-term cryostorage of cells.

关键词： melittin intracellular trehalose membrane stabilization macromolecular protectants cell cryopreservation

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无心插柳——世界杯“爆冷获胜”的贸易创造

世界经济文汇 2024年第3期 99-120页

作者：袁晓燕翁士汉上海大学经济学院

体育精神是世界公民的共同追求和宝贵财富,能够促进各国文化交流和贸易协作。本文利用足球世界杯中“爆冷获胜”作为外生冲击,研究了国家在大型体育赛事中的优异表现对国际贸易的影响,发现:(1)从长期来看,在世界杯中“爆冷获胜”能提高... 详细信息

体育精神是世界公民的共同追求和宝贵财富,能够促进各国文化交流和贸易协作。本文利用足球世界杯中“爆冷获胜”作为外生冲击,研究了国家在大型体育赛事中的优异表现对国际贸易的影响,发现:(1)从长期来看,在世界杯中“爆冷获胜”能提高该国贸易总额及出口额的7.05%和10.71%左右,进口额则不受影响;(2)这一促进效应对发展中国家、人口小国和传统意义上的足球弱国更显著;(3)排除“首次参赛”和“外部经济环境”等干扰后,“爆冷获胜”依然能显著提高该国的出口额,但是对贸易总额和进口额的影响不稳定。

关键词：足球世界杯国际贸易爆冷比赛渐进双重差分法

地方政府如何影响城市人口规模：基于土地供给的视角

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复旦学报(社会科学版) 2024年第4期066卷 147-158页

作者：袁晓燕石磊石秀丽上海大学经济学院复旦大学经济学院

本文基于288个地级市的城市面板数据、259个地级市的人口普查数据，研究了地方政府视域下土地供给与城市人口规模的关系。研究发现，工业用地占建设用地比例每增加10%,城市人口规模增加5.27%～5.88%;商住用地占建设用地比例每增加10%,... 详细信息

本文基于288个地级市的城市面板数据、259个地级市的人口普查数据，研究了地方政府视域下土地供给与城市人口规模的关系。研究发现，工业用地占建设用地比例每增加10%,城市人口规模增加5.27%～5.88%;商住用地占建设用地比例每增加10%,城市人口规模减少3.89%～5.91%。以财政分权程度作为工具变量的两阶段最小二乘(2SLS)分析呈现出一致的结果。机制研究表明，地方政府主导的这种土地差异化供应通过影响商品房的房价及居住模式共同作用于城市人口规模。区分不同学历群体和地区的结果显示：土地政策对高学历人群影响更大；离港口越近，工业用地占比增加会带来更多的人口流入；相较中西部，东部地区工业用地占比会显著促进人口流入，商住用地占比的效应不显著。本文为解决区域经济协调发展的“地随人走”政策提供了进一步的理论及经验证据。

关键词：地方政府城市人口规模工业用地商住用地

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女性高管、环境规制与企业绿色创新

科技创业月刊 2024年第7期37卷 43-48页

作者：袁小燕鲁俊吉首大学商学院湖南吉首416000

女性在职场中的话语权越来越高,其思维与决策方式会影响企业的决策和行为,也会对企业绿色创新产生深刻影响。基于2015-2021年中国A股上市公司数据,实证检验女性高管对企业绿色创新的影响,并考察外部环境规制在女性高管与绿色创新之间的... 详细信息

女性在职场中的话语权越来越高,其思维与决策方式会影响企业的决策和行为,也会对企业绿色创新产生深刻影响。基于2015-2021年中国A股上市公司数据,实证检验女性高管对企业绿色创新的影响,并考察外部环境规制在女性高管与绿色创新之间的调节作用。实证结果表明:女性高管对企业绿色创新具有显著的正向影响,且环境规制正向调节女性高管与绿色创新之间的关系,进行内生性检验、缩短样本时间与替换被解释变量后结果依然稳健。进一步研究发现,女性高管对企业绿色创新的积极作用在两职合一和非重污染行业中表现得更为显著。研究结论可为促进企业绿色创新提供参考。

关键词：女性高管绿色创新环境规制

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Development of L-arginine-based poly(ester urethane)urea for enhanced vascular adaptability

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Science China(Technological Sciences) 2022年第11期65卷 2751-2762页

作者： BAI Shan ZHANG XiangYu ZANG LeiLei REN LiXia yuan xiaoyan School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin300350China

Mismatched biomechanical properties between artificial vascular grafts and native blood vessels can result in intimal hyperplasia,especially for the implantation of small-diameter blood *** biomaterials for vascular repair still remain *** poly(ε-caprolactone)(PCL)has been applied for the preparation of electrospun vascular grafts,but more efforts are needed to improve its compliance with tissue ***,L-arginine-based poly(ester urethane)urea(PEUU)with both elasticity and biodegradability was synthesized so as to enhance the biomechanical properties of vascular grafts by blending electrospinning with PCL in a given mass *** was exhibited that the prepared electrospun PCL/PEUU fibrous membranes were suitable for cell proliferation with normal cell *** importantly,the electrospun membrane with 1/1 mass ratio of PCL/PEUU(PEUU50)showed specific flexibility,exhibiting more suitable mechanical properties matching to the native blood ***,the PEUU50 electrospun membrane demonstrated significantly lower Young’s modulus(9.3±0.8 MPa)and tensile strength(6.0±0.5 MPa),and extremely higher elongation(389%±24%)in wet state than those(16.3±3.0 MPa,11.4±7.1 MPa and 196%±57%,respectively)of the pristine PCL ***,this study demonstrated the great potential of amino acid-based PEUUs for the application in small-diameter vascular grafts.

关键词： poly(ester urethane)urea poly(e-caprolactone) electrospinning vascular grafts mechanical properties

Preparation of Poly(ε-caprolactone)/Poly(ester amide)Electrospun Membranes for Vascular Repair

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Chemical Research in Chinese Universities 2022年第4期38卷 1111-1117页

作者： ZHANG Xiangyu BAI Shan ZANG Leilei CHEN Xiaoqi yuan xiaoyan School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin300350P.R.China Institute of Energy Resources Hebei Academy of SciencesShijiazhuang050081P.R.China

With adjustable amphiphilicity and anionic/cationic charge,biodegradability and biocompatibility,amino acid-based poly(ester amide)s(PEAs)have drawn attention in the research of tissue engineered vascular *** this work,L-phenylalanine-based PEAs with or without L-lysine were synthesized through polycondensation,and ultrafine fibrous grafts consisted of PEAs and poly(ε-caprolactone)(PCL)in given mass ratios were further prepared via blend *** characterizations by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy confirmed the chemical structure,and the wettability indicated that the prepared PCL/PEAs electrospun membranes exhibited less hydrophobic than *** results showed that the PCL/PEAs membranes possessed suitable mechanical properties,which could meet the requirements of artificial blood *** culture and hemolytic tests exhibited that the PCL/PEAs electrospun membranes are *** general,the electrospun grafts of PCL/PEAs could be applied for vascular repair.

关键词： Poly(ester amide) Poly(ε-caprolactone) Electrospun membrane Mechanical property Vascular repair

Sacrificial template synthesis of(V_(0.8)Ti_(0.1)Cr_(0.1))_(2)AlC and carbon fiber@(V_(0.8)Ti_(0.1)Cr_(0.1))_(2)AlC microrods for efficient microwave absorption

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Journal of Materials Science & Technology 2022年第16期111卷 236-244页

作者： Wei Luo Yi Liu Chuangye Wang Dan Zhao xiaoyan yuan Jianfeng Zhu Lei Wang Shouwu Guo School of Material Science and Engineering Shaanxi University of Science and TechnologyXi’an 710021China Department of Electronic Engineering School of Electronic Information and Electrical EngineeringShanghai Jiao Tong universityShanghai 200240China

The morphology of MAX phase powders significantly influences their microwave absorption ***,the traditional synthesis via solid-state reactions produces irregular powders,and the preparation of MAX phase powders with specific morphology remains a ***,(VTiCr)Al C MAX phase microrods were fabricated for the first time in NaCl/KCl molten salts using vanadium,titanium,chromium,aluminum,and short carbon fibers as *** was found that despite acting as a carbon source,carbon fibers also acted as sacrificial *** adjusting the molar ratio of metal powders and short carbon fibers,a series of carbon fiber@(V_(0.8)Ti_(0.1)Cr_(0.1))_(2)AlC microrods with core-sheath structure were also *** fiber@(V_(0.8)Ti_(0.1)Cr_(0.1))_(2)AlC microrods with a molar ratio of 8:2 showed the optimum microwave absorption *** reflection loss(RL)value reached up to–63.26 d B at 2.40 mm,and the effective absorption bandwidth(EAB)was about 5.28 GHz with a thickness of2.02 *** on the electromagnetic parameter analysis and theoretical simulation,the enhanced microwave absorption performance was attributed to the synergistic effect of different factors like dielectric loss,magnetic loss,multiple reflection,and *** work offers a facile route to modulate the morphology of MAX phase powders and may accelerate its application as microwave absorbers.

关键词： MAX phases Microwave absorption Sacrificial template Microrod

Effects of mesencephalic astrocyte-derived neurotrophic factor on sepsis-associated acute kidney injury

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World Journal of Emergency Medicine 2023年第5期14卷 386-392页

作者： Saifeng Chen Xuewei Hao Guo Chen Guorong Liu xiaoyan yuan Peiling Shen Dongfeng Guo Postgraduate Training Base at Shanghai Gongli Hospital Ningxia Medical CollegeShanghai 200135China Department of Emergency Medicine Shanghai Gongli HospitalShanghai 200135China

BACKGROUND:To determine the protective role of mesencephalic astrocyte-derived neurotrophic factor(MANF) in regulating sepsis-associated acute kidney injury(S-AKI).METHODS:A total of 96 mice were randomly divided into the control group,control+MANF group,S-AKI group,and S-AKI+MANF *** S-AKI model was established by injecting lipopolysaccharide(LPS) at 10 mg/kg ***(200 μg/kg) was administered to the control+MANF and S-AKI+MANF *** equal dose of normal saline was administered daily intraperitoneally in the control and S-AKI *** and kidney tissue samples were obtained for biochemical *** blotting was used to detect the protein expression of MANF in the kidney,and enzyme-linked immunosorbent assay(ELISA) was used to determine expression of MANF in the serum,pro-inflammatory cytokines(tumor necrosis factor-α [TNF-α] and interleukin-6 [IL-6]).Serum creatinine(SCr),and blood urea nitrogen(BUN)were examined using an automatic biochemical *** addition,the kidney tissue was observed for pathological changes by hematoxylin-eosin *** comparison between two groups was performed by unpaired Student’s t-test,and statistics among multiple groups were carried out using Tukey’s post hoc test following one-way analysis of variance(ANOVA).A P-value <0.05 was considered statistically ***:At the early stage of S-AKI,MANF in the kidney tissue was up-regulated,but with the development of the disease,it was *** function was worsened in the S-AKI group,and TNF-α and IL-6 were *** administration of MANF significantly alleviated the elevated levels of SCr and BUN and inhibited the expression of TNF-α and IL-6 in the *** pathological changes were more extensive in the S-AKI group than in the S-AKI+MANF ***:MANF treatment may significantly alleviate renal injury,reduce the inflammatory response,and alleviate or reverse kidney tissue *** may have a protective

关键词： Sepsis-associated acute kidney injury Mesencephalic astrocyte-derived neurotrophic factor Renal function Cytokines Endoplasmic reticulum stress

Stabilization or degradation?Post-translational modifications of JAZ proteins in plants

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Molecular Plant 2024年第7期17卷 1002-1004页

作者： xiaoyan Xu Jianping Hu Zheng yuan Joint International Research Laboratory of Metabolic&Developmental Sciences School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghai200240China Department of Energy Plant Research Laboratory and Plant Biology Department Michigan State UniversityEast LansingMI 48824USA

Jasmonates(JAs)are essential hormones that regulate plant responses to biotic and abiotic stresses and are involved in various developmental processes,including flowering time control,floral organ development,and fertility of male and female gametes(Howe et al.,2018).However,our understanding of the mechanisms by which JAs integrate multiple signals to regulate diverse physiological processes remains *** the canonical JA signaling pathway,activated JAs are perceived by the F-box protein receptor CORONATINE INSENSITIVE 1(COl1),which induces the interaction between COl1 and the Jas domain of the repressor proteins JASMONATE-ZIM DOMAIN PROTEINs(JAZs),leading to the ubiquitination and degradation of JAZ *** proteolytic destruction of the JAZ repressors is a crucial step that releases the inhibition of JAZs on the JA response transcription factor MYC2,allowing MYC2 to activate the expression of downstream genes(Howe et al.,2018).Therefore,the stability and specific spatiotemporal expression pattern of the JAZ proteins are critical for the regulation of JA signaling output,as they determine the activation and repression of JA responses.

关键词： translational fertility release

银纳米线SERS快速高灵敏检测水中痕量Hg2+研究

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安全与环境学报 2024年第6期24卷 2408-2421页

作者：陈百利周维李茂婷李成银美茜杨柳袁小燕杨友慧徐习斌四川轻化工大学化学与环境工程学院四川自贡643000 山东大学材料科学与工程学院济南250061 珠海纳金科技有限公司广东珠海519080 宜宾学院理学院四川宜宾644007

水中痕量重金属汞离子(Hg^(2+))对人类健康会构成严重威胁,因此快速高灵敏检测水中痕量Hg^(2+)具有重要科学意义和实际应用价值。为实现这一目标,研究运用银纳米线(silver nanowires, AgNWs)作为表面增强拉曼散射(Surface-Enhanced Rama... 详细信息

水中痕量重金属汞离子(Hg^(2+))对人类健康会构成严重威胁,因此快速高灵敏检测水中痕量Hg^(2+)具有重要科学意义和实际应用价值。为实现这一目标,研究运用银纳米线(silver nanowires, AgNWs)作为表面增强拉曼散射(Surface-Enhanced Raman Scattering, SERS)基底来快速高灵敏检测水中痕量Hg^(2+)。用旋涂法制备了均匀分布的AgNWs基SERS基底,并用罗丹明6G(Rhodamine 6G,R6G)作为拉曼信标分子,以间接检测水中痕量Hg^(2+)。通过研究SERS活性、稳定性、重现性、选择性、AgNWs直径及pH值对其SERS活性的影响,用时域有限差分法(Finite Difference Time Domain, FDTD)模拟了AgNWs表面电场分布情况。结果显示,AgNWs基SERS基底具有良好的活性、优异的信号再现性、稳定性和选择性,SERS活性随着直径的增大而增强,对Hg^(2+)的检测限(Detection Of Limit, LOD)达10-11mol/L,远低于美国环境保护署(The U.S. Environmental Protection Agency, EPA)的饮用水Hg^(2+)浓度标准(10-8mol/L)。在低浓度范围内,SERS特征峰强度(R^(2)=0.9919)有良好的线性关系。FDTD模拟结果为试验结果提供了有力的理论支撑,可为水中检测痕量Hg^(2+)提供新策略,在环境监测中具有广阔的应用前景。

关键词：环境科学技术基础学科表面增强拉曼散射(SERS) 银纳米线(AgNWs) 罗丹明6G 汞离子时域有限差分法

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