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Influencing factor of the characterization and restoration of phase aberrations resulting from atmospheric turbulence based on Principal Component Analysis
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作者 WANG Jiang-pu-zhen WANG Zhi-qiang +2 位作者 ZHANG Jing-hui QIAO Chun-hong FAN Cheng-yu 《中国光学(中英文)》 北大核心 2025年第4期899-907,共9页
Restoration of phase aberrations is crucial for addressing atmospheric turbulence in light propagation.Traditional restoration algorithms based on Zernike polynomials(ZPs)often encounter challenges related to high com... Restoration of phase aberrations is crucial for addressing atmospheric turbulence in light propagation.Traditional restoration algorithms based on Zernike polynomials(ZPs)often encounter challenges related to high computational complexity and insufficient capture of high-frequency phase aberration components,so we proposed a Principal-Component-Analysis-based method for representing phase aberrations.This paper discusses the factors influencing the accuracy of restoration,mainly including the sample space size and the sampling interval of D/r_(0),on the basis of characterizing phase aberrations by Principal Components(PCs).The experimental results show that a larger D/r_(0)sampling interval can ensure the generalization ability and robustness of the principal components in the case of a limited amount of original data,which can help to achieve high-precision deployment of the model in practical applications quickly.In the environment with relatively strong turbulence in the test set of D/r_(0)=24,the use of 34 terms of PCs can improve the corrected Strehl ratio(SR)from 0.007 to 0.1585,while the Strehl ratio of the light spot after restoration using 34 terms of ZPs is only 0.0215,demonstrating almost no correction effect.The results indicate that PCs can serve as a better alternative in representing and restoring the characteristics of atmospheric turbulence induced phase aberrations.These findings pave the way to use PCs of phase aberrations with fewer terms than traditional ZPs to achieve data dimensionality reduction,and offer a reference to accelerate and stabilize the model and deep learning based adaptive optics correction. 展开更多
关键词 phase aberration atmospheric turbulence principal component analysis Zernike polynomials
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Eliminating chromatic aberrations of diffractive lenses in varifocal virtual reality displays
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作者 JIANGHAO XIONG ZUJIAN WANG +2 位作者 YUEFAN SHAN DEWEN CHENG YONGTIAN WANG 《Photonics Research》 2025年第12期3466-3475,共10页
Virtual reality(VR)is regarded as the next-generation display platform for immersive human-computer interaction.To solve the long-existing problem of vergence accommodation conflict in VR,varifocal displays based on t... Virtual reality(VR)is regarded as the next-generation display platform for immersive human-computer interaction.To solve the long-existing problem of vergence accommodation conflict in VR,varifocal displays based on the diffractive Pancharatnam–Berry lens(PBL)are considered as one of the most promising approaches with great compatibility to current display architectures.However,the diffractive nature of PBL leads to serious chromatic aberrations in optical systems,which deteriorates the image quality and discourages its actual usage. 展开更多
关键词 chromatic aberrations varifocal displays diffractive lenses virtual reality vr optical systemswhich vergence accommodation conflict vrvarifocal displays display architectureshoweverthe
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Corneal higher-order aberrations following small incision lenticule extraction for high myopic astigmatism correction
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作者 Yin Liu Cheng Hu +3 位作者 Juan Yu Nian Xiang Bo Zeng Wen-Shan Jiang 《International Journal of Ophthalmology(English edition)》 2025年第7期1349-1356,共8页
AIM:To compare the visual outcomes and corneal higherorder aberrations(HOAs)of patients with high or low myopic astigmatism after small incision lenticule extraction(SMILE).METHODS:A total of 157 eyes of 157 patients ... AIM:To compare the visual outcomes and corneal higherorder aberrations(HOAs)of patients with high or low myopic astigmatism after small incision lenticule extraction(SMILE).METHODS:A total of 157 eyes of 157 patients who underwent SMILE were included in this retrospective,nonrandomized,comparative study.All the eyes which were with the rule astigmatism were divided into high astigmatism group(HAG;astigmatism≤-2.00 D,73 eyes)and low astigmatism group(LAG;astigmatism≥-1.00 D,84 eyes).Visual and refractive examinations were performed,HOAs of the anterior surface,posterior surface,and total cornea of the eyes were evaluated preoperatively and 6mo postoperatively.RESULTS:At the postoperative 6-month follow-up,uncorrected distance visual acuity of 20/20 or better was achieved in 97%and 100%eyes in HAG and LAG respectively and 74%and 100%eyes were within-0.50 D.Vector analysis revealed no significant differences in the correction index(P=0.066),angle of error(P=0.091)or flattening index(P=0.987)between two groups.The magnitude of error was-0.37±0.31 D in HAG and-0.04±0.19 D in LAG(P<0.001).Index of success(IOS)was 0.22±0.09 in the HAG and 0.50±0.46 in the LAG(P<0.001).HOAs of most anterior,posterior and total cornea significantly increased after SMILE,especially the spherical aberration and coma.For HAG,the SMILE procedure induced significantly higher anterior,posterior and total cornea horizontal coma and total corneal total HOAs compared with LAG(P<0.001)and these surgically induced HOAs predominantly originated from the anterior surface of the cornea.CONCLUSION:SMILE surgery induces more HOAs and a mild under-correction of astigmatism in eyes with high astigmatism.The increment in HOAs after SMILE is related to preoperative astigmatism. 展开更多
关键词 small incision lenticule extraction high astigmatism higher-order aberrations MYOPIA
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含偶次非球面的手机镜头降敏设计方法
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作者 王洋 王楚文 顾志远 《光学精密工程》 北大核心 2026年第2期191-200,共10页
在光学设计过程中,光学系统性能的优化与公差分析是分隔开的,理论性能良好的系统公差可能过于严苛,因此,光学系统的降敏设计至关重要。手机镜头通常采用偶次非球面来降低系统的像差和总长,高次项的引入导致由光学表面的失调量引起的像... 在光学设计过程中,光学系统性能的优化与公差分析是分隔开的,理论性能良好的系统公差可能过于严苛,因此,光学系统的降敏设计至关重要。手机镜头通常采用偶次非球面来降低系统的像差和总长,高次项的引入导致由光学表面的失调量引起的像质退化比较严重。本文针对含有偶次非球面的手机镜头,提出了一种基于节点像差理论的降敏设计方法。首先,根据节点像差理论,分析了偶次非球面的圆锥曲面基底部分出现失调时,三阶彗差和像散的Zernike系数变化情况。随后,为了计算偶次非球面的高次项部分由失调引入的波像差变化量,通过光瞳坐标变换,获得了光学表面在失调状态下的光瞳图,并且根据光瞳的坐标变化对波像差变化量进行了计算;最后,建立了适用于含偶次非球面光学系统的实际性能模型,并且利用该模型设计了一个4片式手机镜头。公差分析结果表明:在5μm偏心和5′倾斜公差范围内,经过30 min的优化,手机镜头的RMS波像差均值相较于默认设计方法减少了33%,验证了本文提出的设计方法的有效性。 展开更多
关键词 节点像差理论 降敏设计 非球面 手机镜头
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小F数光学系统宽温域无热化设计
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作者 陈硕 潘宇 +6 位作者 李泓洋 张砚冬 李博 李寒霜 顾国超 范纪泽 张旭 《中国光学(中英文)》 北大核心 2026年第1期143-150,共8页
在宽温域应用场景中,传统光学系统往往难以维持稳定的成像质量,其主要原因在于常规无热化设计方法未能充分考虑玻璃材料在高温与低温下线胀系数与折射率温度系数的差异。针对这一问题,本文提出了一种面向宽温域的无热化设计方法,通过重... 在宽温域应用场景中,传统光学系统往往难以维持稳定的成像质量,其主要原因在于常规无热化设计方法未能充分考虑玻璃材料在高温与低温下线胀系数与折射率温度系数的差异。针对这一问题,本文提出了一种面向宽温域的无热化设计方法,通过重建热像差建模过程,准确表征热像差随温度变化的非线性响应,进而筛选出在宽温域内综合热光焦度最小的玻璃材料组合,并结合镜筒材料热膨胀特性,有效抑制系统焦点漂移。设计验证中,构建了一套焦距为100 mm、F数为2.2、视场角为7°的光学系统。结果表明,在-30℃至270℃的温度范围内,该系统始终保持优异的成像性能:在全视场和全温度条件下,MTF(@56 lp/mm)均大于0.5,弥散斑直径小于9μm,且90%以上的能量聚焦在直径18μm的包围圆内。上述结果充分验证了所提方法的有效性,为宽温域光学系统的无热化设计提供了有力支撑。同时,该方法具备良好的工程适应性,在复杂环境下的成像系统设计中展现出广阔的应用前景。 展开更多
关键词 宽温度范围 光学系统设计 热像差补偿 无热化 可见光范围
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F9基因剪接位点共识区域中内含子突变造成的异常剪接模式研究
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作者 马金 沈滟 +1 位作者 沈国民 高蒙 《南京医科大学学报(自然科学版)》 北大核心 2026年第1期55-67,共13页
目的:确定B型血友病致病基因F9的剪接位点共识序列,并筛选序列相关致病突变,以确定F9基因内含子中主要剪接调控位点。方法:从凝血因子Ⅸ(coagulation factorⅨ,FⅨ)突变数据库(FactorⅨVariant Database)中收集内含子突变,依据F9基因剪... 目的:确定B型血友病致病基因F9的剪接位点共识序列,并筛选序列相关致病突变,以确定F9基因内含子中主要剪接调控位点。方法:从凝血因子Ⅸ(coagulation factorⅨ,FⅨ)突变数据库(FactorⅨVariant Database)中收集内含子突变,依据F9基因剪接位点保守性分析筛选可能影响剪接的致病突变,重点关注患病人数多且致病效应强的突变位点所在区域,结合3种RNA剪接预测软件对突变导致的剪接效应进行预测。之后,采用微型基因剪接检测体系,对所选突变的剪接效应进行体外检测并通过变性毛细管电泳检测不同转录本所占比例,以明确各突变剪接效应的差异,进而确定F9基因剪接共识序列中影响剪接的关键位点。针对具有蛋白编码能力的异常剪接体,构建体外表达体系,通过Western blot及活化部分凝血活酶时间综合评估异常剪接体的胞内表达、胞外分泌及凝血活性状态。结果:序列与突变分析确定F9基因外显子4剪接位点附近的15个突变为靶突变,微型基因剪接实验证实其中14个突变可导致异常剪接,对比软件预测结果,进一步证实计算机预测具有局限性,不能准确预测具体剪接模式及其比例。证实了内含子上经典位点GT-AG的保守性,同时发现供体端+5G同样有利于剪接位点的正确识别,而相对保守的+7A则未对剪接位点识别产生重要作用,此外,模拟经典“AG”序列的深层内含子突变会造成剪接识别错位,显著提高异常剪接比例。蛋白表达与活性分析结果显示,p.D93-G125delinsG和p.G94-D131del两种异常剪接突变体的抗原合成及活性状态与野生型相比差异均有统计学意义(P<0.01)。结论:GT-AG是影响剪接调控的主要位点,F9基因内含子4剪接供体端非保守位点的+5G同样对剪接有调控作用。对不同突变造成剪接调控模式差异进行总结分析,可为大数据分析提供理论依据,并提高生物信息学预测的准确性。 展开更多
关键词 F9基因 内含子突变 剪接异常 B型血友病 致病机制
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基于多颜色空间融合的火灾图像偏色度量化方法
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作者 胡良波 《火力与指挥控制》 北大核心 2026年第1期156-164,共9页
针对火灾防控环境下火灾检测误报率高的问题,提出一种基于多颜色空间动态融合的火灾图像偏色度量化方法。通过构建RGB、HSV、YCBCR和LAB四维联合特征空间,设计双层权重分配机制,并结合火焰光谱先验与烟雾散射模型动态,提出改进的加权方... 针对火灾防控环境下火灾检测误报率高的问题,提出一种基于多颜色空间动态融合的火灾图像偏色度量化方法。通过构建RGB、HSV、YCBCR和LAB四维联合特征空间,设计双层权重分配机制,并结合火焰光谱先验与烟雾散射模型动态,提出改进的加权方差度量与L2归一化联合偏色因子向量,建立跨颜色空间的统计一致性基准。实验表明,该方法在火灾中各混合场景中,类间偏色度差异较单一颜色空间有效提升,类内时空差异衡量精准,有效解决了传统方法在动态光照和烟雾遮蔽下的量化偏差问题,证明了颜色空间混合偏色度量化的优越性,为复杂火灾场景的精准检测提供了新的量化依据。 展开更多
关键词 火灾检测 多颜色空间融合 偏色度量化 动态权重分配 加权方差度量
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矫正人眼高阶像差的全视场个性化眼镜设计与验证
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作者 魏瑞 曾春梅 +1 位作者 卢家旭 余浩墨 《红外与激光工程》 北大核心 2026年第1期235-247,共13页
针对人眼高阶像差引起的视敏度、对比敏感度下降和眩光等视觉问题,提出了一种基于大瞳孔和兼顾实用性的矫正人眼高阶像差的个性化眼镜设计方法。首先,在5~5.5 mm大瞳孔条件下对眼模型进行个性化设计,使其匹配目标眼实测的生理数据和波... 针对人眼高阶像差引起的视敏度、对比敏感度下降和眩光等视觉问题,提出了一种基于大瞳孔和兼顾实用性的矫正人眼高阶像差的个性化眼镜设计方法。首先,在5~5.5 mm大瞳孔条件下对眼模型进行个性化设计,使其匹配目标眼实测的生理数据和波前像差;然后,对镜片采用球面和Zernike环形相位面的型式,在眼球的多个转动角度下,优化Zernike环形相位面,同时控制矢高和屈光度变化,最终得到大瞳孔条件下、有效矫正人眼高阶像差,且兼顾加工可行性和佩戴舒适性的全视场个性化眼镜。对两种目标眼的眼镜设计结果表明,在直视情况下,镜眼系统总高阶像差分别下降了36.04%和29.81%,近视眼镜片在空间频率为80 lp/mm时,不同转动角度(-20°、-10°、0°、10°、20°)下的MTF相比仅矫正低阶离焦像差时提高了41.72%~69.07%,远视眼镜片在空间频率为50 lp/mm时提高了13.95%~43.10%。此外,通过客观和主观的戴镜实验验证了设计方法的有效性。佩戴轴上视场镜片后,两种目标眼的总高阶像差较裸眼数据分别下降了23.33%和20.45%;相比传统的球面镜片和非球面镜片,设计镜片不受眩光影响,眩光敏感度与正常照明下的视敏度测试结果相同,并且能明显提升高频段的对比敏感度。 展开更多
关键词 高阶像差 视觉矫正 个性化眼模型 眼镜设计
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MicroRNA aberrations:An emerging field for gallbladdercancer management 被引量:16
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作者 Vishal Chandra Jong Joo Kim +1 位作者 Balraj Mittal Rajani Rai 《World Journal of Gastroenterology》 SCIE CAS 2016年第5期1787-1799,共13页
Gallbladder cancer(GBC) is infrequent but most lethal biliary tract malignancy characterized by an advanced stage diagnosis and poor survival rates attributed to absence of specific symptoms and effective treatment op... Gallbladder cancer(GBC) is infrequent but most lethal biliary tract malignancy characterized by an advanced stage diagnosis and poor survival rates attributed to absence of specific symptoms and effective treatment options. These necessitate development of early prognostic/predictive markers and novel therapeutic interventions. Micro RNAs(mi RNAs) are small, noncoding RNA molecules that play a key role in tumor biology by functioning like tumor suppressor- or oncogenes and their aberrant expression are associated with the pathogenesis of several neoplasms with overwhelming clinical implications. Since mi RNA signature is tissue specific, here, we focused on current data concerning the mi RNAs abberations in GBC pathogenesis. In GBC, mi RNAs with tumor suppressor activity(mi R-135-5p, mi R-335, mi R-34 a, mi R-26 a, mi R-146b-5p, Mir-218-5p, mi R-1, mi R-145, mir-130a) were found downregulated, while those with oncogenic property(mi R-20 a, mi R-182, mir-155) were upregulated. The expression profile of mi RNAs was significantly associated with GBC prognosis and prediction, and forced over-expression/ inhibition of these mi RNAs was shown to affect tumor growth and development. Further, differential expression of mi RNAs in the blood samples of GBC patients suggest mi RNAs as promising noninvasive biomarker. Thus, mi RNAs represent potential candidate for GBC management, though many hurdles need to be overcome before mi RNAs therapy can be clinically applied to GBC prevention and treatment. 展开更多
关键词 GALLBLADDER cancer MICRORNA aberrations Tumor SUPPRESSOR gene ONCOGENE BIOMARKER Therapy
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ICL V4c植入术后视觉质量的研究进展
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作者 祁云凯 汪洋合 +1 位作者 黄小娟 岳红云 《国际眼科杂志》 2026年第1期86-90,共5页
与其他屈光手术相比,有晶状体眼后房型人工晶状体(ICL)植入手术是目前屈光手术中最受欢迎的术式之一。ICL手术具有可逆性、高清视觉效果、不会改变角膜解剖结构等优点。目前临床最常用的是V4c型有中央孔型晶状体,围手术期不需要行虹膜... 与其他屈光手术相比,有晶状体眼后房型人工晶状体(ICL)植入手术是目前屈光手术中最受欢迎的术式之一。ICL手术具有可逆性、高清视觉效果、不会改变角膜解剖结构等优点。目前临床最常用的是V4c型有中央孔型晶状体,围手术期不需要行虹膜激光打孔术。且术后可获得良好的裸眼视力,然而,部分患者术后早期可能出现视觉干扰现象,如光晕、眩光等,尤其在暗光环境下可能影响视觉舒适度。文章针对ICL V4c术后高阶像差(HOA)、调制传递函数(MTF)、对比敏感度(CS)等视觉质量指标及影响因素进行综述,并探讨术后视觉质量可能存在的相对缺陷与相关机制。 展开更多
关键词 V4c型有晶状体眼后房型人工晶状体(ICL V4c) 视觉质量 高阶像差 调制传递函数 对比敏感度 影响因素
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Comparison of correcting myopia and astigmatism with SMILE or FS-LASIK and postoperative higher-order aberrations 被引量:19
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作者 Peng-Fei Zhao Ya-Bin Flu +3 位作者 Yue Wang Cai-Yun Fu Jing Zhang Chang-Bin Zhai 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2021年第4期523-528,共6页
AIM:To compare the effect of myopia and astigmatism correction and postoperative change in higher-order aberration as results of receiving small-incision lenticule extraction(SMILE)and femtosecond laser-assisted in si... AIM:To compare the effect of myopia and astigmatism correction and postoperative change in higher-order aberration as results of receiving small-incision lenticule extraction(SMILE)and femtosecond laser-assisted in situ keratomileusis(FS-LASIK).METHODS:A prospective and non-randomized controlled study was conducted.The subjects are divided into two groups according to different operations received:229 eyes of 116 patients in the SMILE group and 168 eyes of 86 patients in the FS-LASIK group.All subjects were followed up for 3 mo by monitoring their uncorrected visual acuity(UCVA),best-corrected visual acuity(BCVA),spherical equivalent,higher-order aberrations,and the preoperative and postoperative complications.RESULTS:At 1 wk,1,and 3 mo post-surgery,224 eyes(97.8%),227 eyes(99.1%)and 229 eyes(100%)had UCVA≥20/20 in the SMILE group,while 165 eyes(98.2%),167 eyes(99.4%)and 167 eyes(99.4%)had UCVA≥20/20 in the FS-LASIK group,respectively(χ^(2)=0.146,2.135,and 1.124;all P>0.05).BCVA reduction was not observed in both groups at 1 and 3 mo of post-surgery(χ^(2)=0.734 and 1.898,P>0.05).There was no statistically significant difference in the spherical equivalent between the two groups at 1 and 3 mo post-surgery,though the percentage of the spherical equivalent within±0.50 D at 3 mo postsurgery was 98%in the SMILE group,which was higherthan that of the FS-LASIK group(92%,χ^(2)=1.872,P>0.05).The root mean square(RMS)values of total high-order aberration,coma,and spherical aberration of the two groups increased significantly in the early postoperative period and decreased after 3 mo,but the values were still higher than the preoperative levels(P<0.05);there was no significant difference between the two groups in the RMS values of total higher-order aberrations and specific higherorder aberrations(P>0.05).The incidence of complications in the SMILE group was lower than that in the FS-LASIK group(χ^(2)=14.52,P<0.05).CONCLUSION:SMILE and FS-LASIK can effectively treat myopia,significantly improve visual acuity,and increase the total high-order aberration,spherical aberration,and coma.The incidence of complications after SMILE is relatively low. 展开更多
关键词 MYOPIA femtosecond laser in situ keratomileusis small incision lenticule extraction high order aberrations
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Effects of higher-order aberrations on contrast sensitivity in normal eyes of a large myopic population 被引量:11
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作者 Peng-Fei Zhao Shi-Ming Li +4 位作者 Jing Lu Hong-Min Song Jing Zhang Yue-Hua Zhou Ning-Li Wang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第9期1407-1411,共5页
AIM:To study the relation between higher-order aberrations(HOAs)and contrast sensitivity(CS)in normal eyes among a population of laser in situ keratomileusis(LASIK)candidates.METHODS:In 6629 eyes of 3315 LASIK... AIM:To study the relation between higher-order aberrations(HOAs)and contrast sensitivity(CS)in normal eyes among a population of laser in situ keratomileusis(LASIK)candidates.METHODS:In 6629 eyes of 3315 LASIK candidates,CS were measured under dark environment at the spatial frequencies of 1.5,3,6,12 and 18 cycles per degree(c/d),respectively,using an Optec 6500 visual function tester.Meanwhile,ocular HOAs were measured for a 6.0 mm pupil with a Hartmann-Shack wavefront analyzer.RESULTS:In the study,the subjects with an average spherical equivalent of-4.86±2.07 D were included.HOAs decreased from the third to the sixth order aberrations with predominant aberrations of third-order coma,trefoil and fourth-order spherical aberration.At low and moderate spatial frequencies,CS was negatively correlated with the third-order coma and trefoil aberrations,and decreased with increasing Z31,but increased with increasing Z3-3and Z5-1.At high spatial frequencies,CS decreased with increasing Z3-3and increased with increasing Z5-1.CONCLUSION:At a large pupil size of 6.0 mm,the thirdorder aberrations,but not the total aberrations,are the main factors affecting CS.Vertical coma is negatively correlated with CS. 展开更多
关键词 MYOPIA contrast sensitivity higher-orderaberrations COMA spherical aberration
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Comparison of two types of visual quality analyzer for the measurement of high order aberrations 被引量:9
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作者 Jing Hao Lin Li +1 位作者 Fang Tian Hong Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第2期292-297,共6页
AIM: To compare the difference and agreement of KR- lW and iTrace for measurement of high order aberrations.METHODS: KR-1W and iTrace were respectively used in a group of healthy people (40 volunteers, 32 eyes) to... AIM: To compare the difference and agreement of KR- lW and iTrace for measurement of high order aberrations.METHODS: KR-1W and iTrace were respectively used in a group of healthy people (40 volunteers, 32 eyes) to measure the high order aberration (HOA) of corneal, internal and total ocular. The clinical difference and agreement of two instruments were respectively evaluated by paired-samples 1-test and Bland-Altman analysis. RESULTS: The paired-samples t-test showed that the corneal HOA measured by the two instruments had no statistical differences (P〉0.05); but the internal and total ocular HOA had significant statistical differences (P〈 0.05), and the mean results measured by iTrace were higher than that of KR-1W. However, Bland-Altman analysis revealed that the HOA of corneal and internal were all in 95% limits of agreement; and just one point of total ocular HOA was beyond the 95% limits of agreement. CONCLUSION: KR-1W and iTrace were consistent well in the measurement of corneal, internal and total ocular HOA, especially for the cornea. 展开更多
关键词 KR-IW iTrace high order aberration difference AGREEMENT
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Relationship between higher-order aberrations and myopia progression in schoolchildren: a retrospective study 被引量:8
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作者 Ning Zhang Xu-Bo Yang +5 位作者 Wen-Qiu Zhang Long-Qian Liu Guang-Jing Dong Tao-Wen Chen Meng Liao Xuan Liao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2013年第3期295-299,共5页
AIM: To investigate the relationship between higher- order aberration (HOA) and myopic progression in schoolchildren. ·METHODS: Between April 23 2011 and August 29, 2011 in the children’s myopia outpatient clini... AIM: To investigate the relationship between higher- order aberration (HOA) and myopic progression in schoolchildren. ·METHODS: Between April 23 2011 and August 29, 2011 in the children’s myopia outpatient clinic of the West China Hospital of Sichuan University, 148 eyes of 74 schoolchildren were reviewed. HOAs for a 6 -mm pupil were measured with an aberrometer. Myopic progression rate was defined according to the change in spherical equivalent refraction (SER) divided by the time span (years). Subjects with myopic progression rate of ≥0.50 diopters (D) were classified as the ’fast’group and the subjects with myopic progression rate of 【0.50D were classified as the’slow’group. A retrospective study was conducted to compare HOA between the two groups, using root mean square (RMS) values and Zernike coefficients. ·RESULTS: The RMS values of HOA (t =2.316, P =0.02), HOA without Z 4 0 (t =2.224, P =0.03),third-order aberrations (t’ =2.62, P =0.01), and coma (t’ =2.49, P =0.01) were significantly higher in the fast group than those in the slow group. The individual Zernike coefficients of Z 3 -1 (t = -2.072, P =0.04) and Z 5 1 (Z =-2.627, P =0.01) displayed statistically significant differences between the two groups. Significant correlations were found between the RMS values of HOA (r =0.193, P =0.019), RMS values of HOA without Z 4 0 (r =0.23, P =0.005), RMS values of coma(r =0.235,P =0.004),RMS values of third-order aberrations (r =0.243, P =0.003), and the progression rate. · CONCLUSION: Our results provide evidence of a relationship between HOA and myopic progression. In a future prospective longitudinal study, we aim to verify whether HOA is a risk factor for myopic progression. 展开更多
关键词 ABERRATION MYOPIA CHILDREN disease progression refractive errors/etiology
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The correlation and overlaps between PD-L1 expression and classical genomic aberrations in Chinese lung adenocarcinoma patients: a single center case series 被引量:6
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作者 Jianghua Wu Wei Sun +7 位作者 Haiyue Wang Xiaozheng Huang Xinyu Wang Weiyang Jiang Ling Jia Ping Wang Qin Feng Dongmei Lin 《Cancer Biology & Medicine》 SCIE CAS CSCD 2019年第4期811-821,共11页
Objective:To investigate the correlation and overlaps between PD-L1 expression and classical genomic aberrations in Chinese lung adenocarcinoma(LADC)patients.Methods:We reviewed 428 consecutive,surgically resected cas... Objective:To investigate the correlation and overlaps between PD-L1 expression and classical genomic aberrations in Chinese lung adenocarcinoma(LADC)patients.Methods:We reviewed 428 consecutive,surgically resected cases of LADC from October 2015 to December 2016 from our center.PD-L1 expression was evaluated based on tumor proportion score(TPS).Correlation and co-occurrence of PD-L1 expression level with those of classical driver genes,such as EGFR,ALK,ROS-1,and KRAS and with clinical variables and disease-free survival(DFS)were analyzed.Results:Seventy of the 428 cases(16.4%)showed TPS≥1%,and 21 cases(4.9%)showed TPS≥50%.PD-L1 positive expression was significantly associated with male gender,smoking,advanced TNM stage,and solid histologic subtype.Both TPS≥1% and ≥50%were correlated with the absence of an EGFR mutation(P<0.001)and the presence of ALK rearrangement(P=0.024).KRAS mutation was associated with TPS≥50%(P=0.035).PD-L1 positivity commonly overlapped with the alterations of classical driver oncogenes(58.5%with TPS≥1% and 42.9% with TPS≥50%).Approximately three-quarters of PD-L1 positive cases co-occurred with classical therapeutic-gene aberrations in cases with stage III/IV cancer or cancer progression.LADC could be divided into four subgroups based on the expression profile of current routine biomarkers for potential therapeutic strategies.Conclusions:PD-L1 expression is not only closely correlated with classic gene alterations but also commonly overlaps with the aberrations of classical driver oncogenes in Chinese LADC patients.These findings provide a useful overview of clinical strategies that rely on the profile of routinely used molecular biomarkers. 展开更多
关键词 Lung adenocarcinoma PD-L1 expression classical genomic aberrations molecular biomarkers
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Antioxidants in aqueous extract of Myristica fragrans(Houtt.) suppress mitosis and cyclophosphamide-induced chromosomal aberrations in Allium cepa L.cells 被引量:4
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作者 Akeem AKINBORO Kamaruzaman Bin MOHAMED +2 位作者 Mohd Zaini ASMAWI Shaida Fariza SULAIMAN Othman Ahmad SOFIMAN 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2011年第11期915-922,共8页
In this study, freeze-dried water extract from the leaves of Myristica fragrans (Houtt.) was tested for mutagenic and antimutagenic potentials using the Allium cepa assay. Freeze-dried water extract alone and its co... In this study, freeze-dried water extract from the leaves of Myristica fragrans (Houtt.) was tested for mutagenic and antimutagenic potentials using the Allium cepa assay. Freeze-dried water extract alone and its combination with cyclophosphamide (CP) (50 mg/kg) were separately dissolved in tap water at 500, 1000, 2000, and 4000 mg/kg. Onions (A. cepa) were suspended in the solutions and controls for 48 h in the dark. Root tips were prepared for microscopic evaluation. 2,2-Diphenyl-l-picrylhydrazyl (DPPH) free radicals' scavenging power of the extract was tested using butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) as standards. Water extract of Myristica fragrans scavenged free radicals better than BHA, but worse than BHT. The extract alone, as well as in combination with CP suppressed cell division, and induced chromosomal aberrations that were insignificantly different from the negative control (P≤0.05). However, cytotoxic and mutagenic actions of CP were considerably suppressed. The observed effects on cell division and chromosomes of A. cepa may be principally connected to the antioxidant properties of the extract. The obtained results suggest mitodepressive and antimutagenic potentials of water extract of the leaves of M. fragrans as desirable properties of a promising anticancer agent. 展开更多
关键词 Allium cepa ANTIOXIDANTS Chromosomal aberration CYCLOPHOSPHAMIDE Mitotic index
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Comparative study of visual acuity and aberrations after intralase femtosecond LASIK:small corneal flap versus big corneal flap 被引量:4
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作者 Ya-Li Zhang Lei Liu +5 位作者 Chang-Xia Cui Ming Hu Zhao-Na Li Li-Jun Cao Xiu-Hua Jing Guo-Ying Mu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2013年第5期641-645,共5页
AIM:To study the effects of different flap sizes on visual acuity,refractive outcomes,and aberrations after femtosecond laser for laser in situ keratomileusis(LASIK).METHODS:In each of the forty patients enrolled,1 ey... AIM:To study the effects of different flap sizes on visual acuity,refractive outcomes,and aberrations after femtosecond laser for laser in situ keratomileusis(LASIK).METHODS:In each of the forty patients enrolled,1 eye was randomly assigned to receive treatment with a 8.1mm diameter corneal flap,defined as the small flap,while the other eye was treated with a 8.6mm diameter corneal flap,defined as the big flap.Refractive errors,visual acuity,and higher-order aberrations were compared between the two groups at week 1,month 1 and 3 postoperatively. RESULTS:The postoperative refractive errors and visual acuity all conformed to the intended goal.Postoperative higher-order aberrations were increased,especially in spherical aberration(Z12) and vertical coma(Z7).There were no statistically significant differences between the two groups in terms of postoperative refractive errors,visual acuity,root mean square of total HOAs(HO-RMS),trefoil 30°(Z6),vertical coma(Z7),horizontal coma(Z8),trefoil 0°(Z9),and spherical aberration(Z12) at any point during the postoperative follow-up.CONCLUSION:Both the small and big flaps are safe and effective procedures to correct myopia,provided the exposure stroma meets the excimer laser ablations.The personalized size corneal flap is feasible,as we can design the size of corneal flap based on the principle that the corneal flap diameter should be equal to or greater than the sum of the maximum ablation diameter and apparatus error. 展开更多
关键词 femtosecond laser laser in situ keratomileusis refractive surgery FLAP visual acuity ABERRATION
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Analysis of ocular structural parameters and higher-order aberrations in Chinese children with myopia 被引量:5
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作者 Xue Li Qi Hu +3 位作者 Qian-Ru Wang Zi-Qing Feng Fan Yang Chun-Yu Du 《World Journal of Clinical Cases》 SCIE 2021年第27期8035-8043,共9页
BACKGROUND Myopia and high myopia are global public health concerns.Patients with high myopia account for 0.5%-5.0%of the global population.AIM To examine diopters,axial length(AL),higher-order aberrations,and other o... BACKGROUND Myopia and high myopia are global public health concerns.Patients with high myopia account for 0.5%-5.0%of the global population.AIM To examine diopters,axial length(AL),higher-order aberrations,and other ocular parameters in Chinese children with myopia,to analyze the influence of structural parameters associated with myopia on visual quality,and to provide a theoretical basis for the prevention and treatment of childhood myopia and high myopia.METHODS This study included 195 children aged 6–17 years with myopia.The AL was measured with an ultrasonic ophthalmic diagnostic instrument,and the aberrations,corneal curvature(minimum K1,maximum K2,and average Km),central corneal thickness,anterior chamber depth,and anterior chamber angle were measured using a Sirius three-dimensional anterior segment analyzer.Using a standard formula,the corneal radius of curvature R(337.3/Km)and AL/R values were obtained.RESULTS The diopter of high myopia compared with low-middle myopia was correlated with age and AL(r=-0.336,-0.405,P<0.001),and AL of high myopia was negatively correlated with K1,K2,and Km(r=-0.673,-0.661,and-0.680,respectively;P<0.001),and positively correlated with age and the anterior chamber depth(r=0.214 and 0.275,respectively;P<0.05).AL/R was more closely related to diopter than AL in children with myopia,and 94.4%of children with myopia had an AL/R of>3.00.CONCLUSION The ocular structural parameters of children change because of different diopters.AL/R is more specific and sensitive than AL in evaluating the refractive status of myopia in children.An AL/R of>3.00 may be used as a specific index of myopia in children.There are differences in AL/R between high myopia and low-middle myopia,which can be used for the classification of ametropia.The degree of myopia has a certain influence on higher-order aberrations. 展开更多
关键词 MYOPIA Higher-order aberrations DIOPTER Axial length Cornea radius of curvature
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Antimutagenic potential of curcumin on chromosomal aberrations in Allium cepa 被引量:3
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作者 RAGUNATHAN Irulappan PANNEERSELVAM Natarajan 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第7期470-475,共6页
Turmeric has long been used as a spice and food colouring agent in Asia. In the present investigation, the antimutagenic potential of curcumin was evaluated in Allium cepa root meristem cells. So far there is no repor... Turmeric has long been used as a spice and food colouring agent in Asia. In the present investigation, the antimutagenic potential of curcumin was evaluated in Allium cepa root meristem cells. So far there is no report on the biological properties of curcumin in plant test systems. The root tip cells were treated with sodium azide at 200 and 300 μg/ml for 3 h and curcumin was given at 5, 10 and 20 μg/ml for 16 h, prior to sodium azide treatment. The tips were squashed after colchicine treatment and the cells were analyzed for chromosome aberration and mitotic index. Curcumin induces chromosomal aberration in Allium cepa root tip cells in an insignificant manner, when compared with untreated control. Sodium azide alone induces chromosomal aberrations significantly with increasing concentrations. The total number of aberrations was significantly reduced in root tip cells pretreated with curcumin. The study reveals that curcumin has antimutagenic potential against sodium azide induced chromosomal aberrations in Allium cepa root meristem cells. In addition, it showed mild cytotoxicity by reducing the percentage of mitotic index in all curcumin treated groups, but the mechanism of action remains unknown. The antimutagenic potential of curcumin is effective at 5 μg/ml in Allium cepa root meristem cells. 展开更多
关键词 Chromosomal aberrations Sodium azide GENOTOXICITY Allium cepa
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Ocular higher-order aberrations and mesopic pupil size in individuals screened for refractive surgery 被引量:3
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作者 Seyed Javad Hashemian Mohammad Soleimani +4 位作者 Alireza Foroutan Mahmood Joshaghani Mohammad Jafar Ghaempanah Mohammad Ebrahim Jafari Mehdi Yaseri 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2012年第2期222-225,共4页
AIM: To study the distribution of ocular higher-order aberrations(HOAs) and mesopic pupil size in individuals screened for refractive surgery. · METHODS: Ocular HOAs and mesopic pupil size were studied in 2 458 e... AIM: To study the distribution of ocular higher-order aberrations(HOAs) and mesopic pupil size in individuals screened for refractive surgery. · METHODS: Ocular HOAs and mesopic pupil size were studied in 2 458 eyes of 1 240 patients with myopia, myopic astigmatism and compound myopic astigmatism and 215 eyes of 110 patients with hyperopia, hyperopic astigmatism and compound hyperopic astigmatism using the Zywave aberrometer (Busch& Lomb). All patients had correctable refractive errors without a history of refractive surgery or underlying diseases. Root-mean-square values of HOAs, total spherical aberration, total coma and mesopic pupil size were analyzed. Ocular HOAs were measured across a ≥ 6.0 mm pupil, and pupil size measurements were performed under the mesopic condition. · RESULTS: The mean values of HOAs, total spherical aberration and total coma in the myopic group were 0.369 μm, ±0.233, 0.133±0.112μm and 0.330±0.188μm, respectively. In the hyperopic group the mean values of HOAs, total spherical aberration and total coma were 0.418μm±0.214, 0.202±0.209μm and 0.343±0.201μm, respectively. Hyperopes showed greater total HOAs (P <0.01) and total spherical aberration (P <0.01) compared to myopes. In age-matched analysis, only the amount of total spherical aberration was higher in the hyperopic group (P =0.05). Mesopic pupil size in the myopic group was larger (P ≤0.05). · CONCLUSION: The results suggested that significant levels of HOAs were found in both groups which are important for planning refractive surgeries on Iranians. There were significantly higher levels of total spherical aberration in hyperopes compared to myopes. Mesopic pupil size was larger in myopic group. 展开更多
关键词 corneal wavefront aberration PUPIL mesopic vision RACE MYOPIA HYPEROPIA
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