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Inhibition of corneal fibrosis by Smad7 in rats after photorefractive keratectomy

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Chinese Medical Journal 2013年第8期126卷 1445-1450页

作者： WANG Ti ZHOU Xing-tao YU Yan ZHU Jing-yin DAI Jin-hui qu Xiao-mei LE Qi-hua CHU Ren-yuan Department of Ophthalmology Eye & ENT Hospital of FudanUniversity Shanghai 20003 China Department of Ophthalmology the 85th Hospital of People'SLiliberation Army Shanghai 200052 China Department of Safety Assessment Merck Research LaboratoriesWest Point Pennsylvania USA Department of Ophthalmology Huadong Hospital of FudanUniversity Shanghai 200040 China

Background Haze or corneal subepithelial fibrosis is one of the common complications after refractive surgery procedures, such as photorefractive keratectomy （PRK）, laser epithelial keratomileusis, and epipolis laser in situ keratomileusis, which would result in refractive regression, decreased visual quality, and corneal opacification. Haze directly resulted from corneal fibrosis mediated by transforming growth factor β （TGFβ）. SmadT, an inhibitory Smad, can inhibit TGFβ signal transduction. Recently, the effects of Smad7 on the inhibition of fibrosis in several organs have been studied, while little is known about the effects on cornea after PRK. This study was aimed to determine the effects of lentiviral-mediated Smad7 gene expression on corneal fibrosis in rats after PRK. Methods Four different experimental groups were established using right eyes of Sprague-Dawley rats. Thirty-two eyes underwent de-epithelialization only and served as a sham operation group （group 1）. Ninety-six eyes underwent PRK operation and were further divided into group 2 （the PRK group） without lentivector administration, group 3 （the Lv-blank group） with control lentiviral vector without Smad7 administration, and group 4 （the Lv-Smad7 group） with Smad7 expressing lentiviral vector Smad7 administration. At 1 day, 1 week, 1 month, and 3 months after PRK, the transfection efficiency was determined by measuring the fluorescence signal as well as Smad7 protein and mRNA levels. Corneas were further processed for immunoblotting to assess the phosphorylation of Smad2 as a downstream event of TGFβ/Smad signaling. The expression of fibrotic markers, such as c（-smooth muscle actin （c（-SMA）, Type III collagen （collagen III）, and cell cycle-related marker Ki67, was measured by quantitative real-time reverse transcription polymerase chain reaction （RT-PCR）. Results Lentivirus-mediated exogenous Smad7 gene expression in rat corneal tissue resulted in reduced activation of TGFβ/Smad signaling caused by

关键词： cornea fibrosis Smad7 transforming growth factor β, gene therapy, photorefractive kerateetomy

Differences of carbon and nitrogen stoichiometry between different habitats in two natural Korean pine forests in Northeast China's mountainous areas

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Journal of Mountain Science 2022年第5期19卷 1324-1335页

作者： WANG Ya-fei DUAN Wen-biao qu mei-xue CHEN Li-xin LAN Hang-yu YANG Xi-feng MENG Si-jing CHEN Jia School of Forestry Northeast Forestry UniversityHarbin 150040China

There is a strong link between vegetation and environmental ***,to elucidate how the stoichiometric characteristics of plants respond to different habitats,we studied organic carbon(C)and total nitrogen(N)stoichiometry characteristics of plants in four different habitats of two different natural Korean pine *** of the habitats(gaps,mounds,and pits)were formed via tree uprooting,whereas an undisturbed site(closed canopies)was used as a *** followings were our main findings:(1)the organic carbon content of more than half of the 12 picked plants showed significant differences in different *** of the plants in pit-mound complexes exhibited lower organic carbon contents than plants in gaps and closed canopies;(2)there was no significant differences in the total nitrogen content in 13 of the 25 groups of plant samples;(3)interestingly,the C/N of the sample groups with significant differences in total nitrogen also showed significant differences;(4)there was no significant variations in the stoichiometric characteristics of plants that grew in gaps;however,the variations among plants that grew in pits and mounds were significant;(5)through redundancy analysis(RDA),we find that the main factors effecting the C and N stoichiometric characters of the plants were plants own regulation and the change of photosynthetically active radiation(PAR).In conclusion,the C and N stoichiometric characteristics of plants did not respond to gap formations,but they did strongly respond to pit-mound complex *** active radiation was the most important effective factor to plants in the four habitats.

关键词： Uprooting Site type Carbon Nitrogen Stoichiometric characteristics

Formation and ecological response of sand patches in the protection system of Shapotou section of the Baotou-Lanzhou railway,China

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Journal of Arid Land 2024年第2期16卷 298-313页

作者： DUN Yaoquan qu Jianjun KANG Wenyan LI Minlan LIU Bin WANG Tao SHAO mei Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China College of Urban and Environmental Sciences Northwest UniversityXi'an 710100China Zhongwei Works Section of China Railway Lanzhou Bureau Group Company Limited Zhongwei 755000China

The development of bare patches typically signifies a process of ecosystem *** the protection system of Shapotou section of the Baotou-Lanzhou railway,the extensive emergence of bare sand patches poses a threat to both stability and ***,there is limited knowledge regarding the morphology,dynamic changes,and ecological responses associated with these sand ***,we analyzed the formation and development process of sand patches within the protection system and its effects on herbaceous vegetation growth and soil nutrients through field observation,survey,and indoor analysis *** results showed that sand patch development can be divided into three stages,i.e.,formation,expansion,and stabilization,which correspond to the initial,actively developing,and semi-fixed sand patches,*** average dimensions of all sand patch erosional areas were found to be 7.72 m in length,3.91 m in width,and 0.32 m in *** actively developing sand patches were the largest,and the initial sand patches were the *** the stage of formation and expansion,the herbaceous community composition changed,and the plant density decreased by more than 50.95%.Moreover,the coverage and height of herbaceous plants decreased in the erosional area and slightly increased in the depositional lobe;and the fine particles and nutrients of soils in the erosional area and depositional lobe showed a decreasing *** the stabilization phases of sand patches,the area from the inlet to the bottom of sand patches becomes initially covered with *** and 0-2 cm surface soil condition improved in the erosional area,but this improvement was not yet evident in the depositional *** such as disturbance,climate change,and surface resistance to erosion exert notable influences on the formation and dynamics of sand *** results can provide evidence for the future treatment of sand patches and the management of the pro

关键词： railway protection system sand patch morphology vegetation characteristic soil property

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梯形永磁体盘式无铁心电机的设计与研究

电机与控制学报 2016年第8期20卷 74-82页

作者：谢颖曲春梅哈尔滨理工大学电气与电子工程学院黑龙江哈尔滨150080

针对永磁盘式无铁心同步电机的轴向磁场结构,在现有Halbach永磁阵列的基础上,提出一种梯形结构永磁体阵列。详细阐述该电机的结构与优点,利用有限元方法研究了不同梯形结构永磁体阵列对气隙磁密的影响,根据气隙磁场中的谐波含量及空载... 详细信息

针对永磁盘式无铁心同步电机的轴向磁场结构,在现有Halbach永磁阵列的基础上,提出一种梯形结构永磁体阵列。详细阐述该电机的结构与优点,利用有限元方法研究了不同梯形结构永磁体阵列对气隙磁密的影响,根据气隙磁场中的谐波含量及空载反电势畸变率选取最优转子结构。该结构在保证与传统结构永磁体材料用量相当的前提下,有效提高气隙磁密的基波,降低谐波含量。由于轴向磁场结构的特殊性,给出该电机的设计规则,如磁极尺寸和导体占空比的确定。计算了电机在负载工况下不同定子电流对交直轴电感的影响,为该类电机的设计提供了一定的参考价值。

关键词：盘式无铁心电机 Halbach阵列梯形永磁体有限元方法气隙磁密

Reinforcement of High Impact Polystyrene by Aramid Nanoparticle Fillers Prepared via an In situ Bottom-up Approach

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Chinese Journal of Polymer Science 2024年第8期42卷 1167-1176页

作者： Xiang-Jun Gong Zhi-Ping Zhao Chang-mei Sun Ying Zhang Rong-Jun qu Ying Wang School of Chemistry and Materials Science Ludong UniversityYantai 264025China

In this work,aramid nanoparticles(ANPs)were prepared in dimethyl formamide(DMF)solution containing high impact polystyrene(HIPS)via a bottom-up *** electron microscopy(TEM)images showed that the obtained ANPs were evenly distributed in the HIPS matrix without any *** composition of the ANPs,i.e.,poly(p-phenyl-p-phenylenediamine)(PPTA),was confirmed by Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS)and X-ray diffractometer(XRD).The ANP/HIPS composites,obtained after ethanol precipitation,were added to neat HIPS as fillers to fabricate ANP/HIPS composite *** surface roughness and the glass transition temperature(T_g)of the sheets were characterized by atomic force microscope(AFM)and differential scanning calorimetry(DSC),*** with neat HIPS,the mechanical properties of the composite sheet were significantly improved,and the Young's modulus increased from 246.55 MPa to 2025.12 MPa,the tensile strength increased from 3.07 MPa to 29.76 MPa,and the toughness increased from 0.32 N/mm^2 to 3.92 N/mm^2,with an increase rate of 721%,869%and 1125%,***,the thermal stability of the composites improved with the increase in ANP content.

关键词： High impact polystyrene PPTA nanoparticle Reinforce Mechanical property

原液着色UHMWPE纤维用炭黑色浆的制备工艺

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合成纤维 2024年第8期53卷 41-44,63页

作者：徐广海刘艳玲厉勇路继群曲延梅山东南山智尚科技股份有限公司山东烟台265706 烟台南山学院纺织与服装学院山东烟台265706 烟台市功能性纤维及纺织品重点实验室山东烟台265706

探讨了不同种类炭黑、超分散剂的选择及用量对炭黑色浆分散稳定性的影响,优化了炭黑色浆的工艺配方,并对色浆的可纺性进行验证,分析了炭黑粒子在纤维中的粒径大小、分散状态和相容性。结果表明:以质量分数为10%的4#炭黑和质量分数为20%... 详细信息

探讨了不同种类炭黑、超分散剂的选择及用量对炭黑色浆分散稳定性的影响,优化了炭黑色浆的工艺配方,并对色浆的可纺性进行验证,分析了炭黑粒子在纤维中的粒径大小、分散状态和相容性。结果表明:以质量分数为10%的4#炭黑和质量分数为20%的超分散剂A所制备出的炭黑色浆具有良好的耐热贮存稳定性,颜料粒子尺寸可达到纳米级别,且与超高分子质量聚乙烯(UHMWPE)纺丝原液相容性好;该色浆适用于原液着色UHMWPE纤维的生产。

关键词：炭黑色浆超分散剂研磨分散工艺原液着色 UHMWPE黑色纤维

Vibrio parahaemolyticus O10:K4:An Emergent Serotype with Pandemic Virulence Traits as Predominant Clone Detected by Whole-Genome Sequence Analysis--Beijing Municipality,China,2021

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China CDC weekly 2022年第22期4卷 471-477页

作者： Ying Huang Bing Lyu Xin Zhang Yi Tian Changying Lin Lingyu Shen Hanqiu Yan Daitao Zhang Lei Jia mei qu quanyi Wang Beijing Center for Disease Prevention and Control Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food PoisoningBeijingChina

Introduction:Vibrio parahaemolyticus(***)is a common foodborne pathogen which causes gastroenteritis in humans,especially the O3:K6 pandemic clone which is still a prominent serotype in Beijing,*** this study,we observed a novel serotype O10:K4 isolated from clinical diarrhea cases,which became the most prevalent clone in ***:73 clinical isolates were collected through sentinel hospitals’surveillance in *** agglutination testing and antimicrobial susceptibility testing were *** genome sequencing was applied to characterize 73 *** strains and complete phylogenetic ***:Seven serotypes were identified among 73 strains.O10:K4 was the most common serotype(83.6%),followed by O2:KUT,O4:KUT,and O1:*** sequence typing divided the 73 isolates into 10 sequence types(STs)with ST3 as the most prevalent,which covered all O10:K4 *** isolates were sensitive to common antimicrobial agents apart from *** the O10:K4 isolates were positive for the thermostable direct hemolysin gene,toxRS/new,and orf8,and negative for the TDH-related hemolysin *** whole genome sequencing-single nucleotide polymorphism phylogenetic analysis revealed O10:K4 strains formed a main genetic lineage,which was genetically distinct from other *** also demonstrated the presence of two type III secretion system genes(T3SS1 and T3SS2)andβlactamase resistance gene blaCARB-22 in all O10:K4 ***:The study confirmed the emergence of *** O10:K4 possessing virulence factors similar to the O3:K6 pandemic clone,which may have enabled them to become prevalent in Beijing,China.

关键词： Whole diarrhea Serum

The Application of Stylistics in British and American Literature Teaching

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Sino-US English Teaching 2015年第11期12卷 869-873页

作者： XU Li-mei qu Lin-lin Changchun University Changchun China

Stylistics applies modem linguistic theory to the description of and analysis into varieties of language and their stylistic features. As such it may serve to investigate the styles of British and American literary works, thus facilitating the teaching of British and American literature. This paper, after surveying the basic stylistic theory and its relevance to research on and teaching of literature, illustrates how to effectively adopt the method of stylistic analysis in the teaching of British and American literature

关键词： stylistics style teaching of British and American literature

Scleral ultrastructure and biomechanical changes in rabbits after negative lens application

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International Journal of Ophthalmology(English edition) 2018年第3期11卷 354-362页

作者： Xiao Lin Bing-Jie Wang Yen-Chiao Wang Ren-Yuan Chu Jin-Hui Dai Xing-Tao Zhou Xiao-mei qu Hong Liu Hao Zhou Department of Ophthalmology & Visual Science Eye & ENT Hospital Shanghai Medical College Fudan University Key Laboratory of Myopia Ministry of Health Fudan University Shanghai Key Laboratory of Visual Impairment and Restoration Fudan University School of Optometry Indiana University

AIM： To address the microstructure and biomechanical changes of the sclera of rabbits after negative lens application by spectacle frame apparatus. METHODS： Five New Zealand rabbits of seven weeks post-natal were treated with -8 D lens monocularly over the course of two weeks. Refractive errors and axial length （AXI.） were measured at the 1st, 7th and 14th days of the induction period. Ultrastructure of sclera was determined with electron microscopy. Biomechanical properties were tested by an Instron 5565 universal testing machine. RESULTS： ***-induced （1.1） eyes elongated more rapidly compared with fellow eyes with AXI. values of 15.56±0.14 and 15.21±0.14 mm （P〈0.01）. Fibril diameter was significantly smaller in the I.I eyes compared with control ones in the inner, middle, and outer layers （inner layer, 63.533 vs 76.467 nm; middle layer, 92.647 vs 123.984 nm; outer layer, 86.999 vs 134.257 nm, P〈0.01, respectively）. In comparison with control eyes, macrophage-like cells that engulfed fibroblasts, dilated endoplasmic reticulum, and vacuoles in fibroblasts were observed in the inner and middle stroma in the/U eyes. Ultimate stress and Young＇s modulus were lower in the I.I eyes compared with those in the control eyes. CONCLUSION： Negative lens application alters eye growth, and results in axial elongation with changes in scleral ultrastructural and mechanical properties.

关键词： negative lens rabbit biomechanics sclera ultrastructure