AIM:To assess the visual acuity and visual quality of cataract patients who received femtosecond laser-assisted cataract surgery(FLACS)and multifocal intraocular lens(MIOL)implantation with an improved polishing techn...AIM:To assess the visual acuity and visual quality of cataract patients who received femtosecond laser-assisted cataract surgery(FLACS)and multifocal intraocular lens(MIOL)implantation with an improved polishing technique during a 1-year follow-up period.METHODS:This study included 74 eyes from 37 patients,comprising 17 males and 20 females,with a mean age of 51.74±7.80 years.Using a coin toss method,one eye per patient was randomly selected for improved anterior capsular polishing,while the other eye received standard irrigation/aspiration(I/A)polishing.The polishing group consisted of 37 eyes,including 21 right and 16 left eyes,while the control group comprised the contralateral fellow eyes of the same individuals in the polishing group.Visual acuity and quality of the patients were evaluated before surgery and at 1 wk,1,6,and 12 mo after surgery.The OPD-Scan III was utilized to assess high-order aberrations,while the optical quality analysis system(OQAS)was employed to evaluate modulation transfer function(MTF cutoff),Strehl ratio(SR),and objective scatter index(OSI)for the purpose of visual quality assessment.Paired t-tests and repeated measures analysis of variance(ANOVA)were utilized to compare the results,and the SNK-q post hoc test was applied to identify significant differences.RESULTS:The polishing group’s uncorrected distant visual acuity(UDVA)and uncorrected near visual acuity(UNVA)significantly improved 1-week post-surgery(all P<0.05).At 12-months,UDVA,UNVA,and corrected distant visual acuity(CDVA)were better than the control group(P<0.05).The MTF cutoff,SR,OSI,and high-order aberrations in the polishing group also showed significant improvements compared to the control group at 12 mo(P<0.05).CONCLUSION:The improved capsular polishing method has been demonstrated to effectively maintain visual acuity and visual quality in patients with MIOL after FLACS within 1 a.展开更多
【目的】随着智慧城市建设中信息技术的深度应用,GNSS轨迹数据呈爆炸式增长,但其轨迹生成过程易受信号干扰与传感器故障影响而产生噪声。本文旨在设计新型噪声识别与修复算法,以提升原始GNSS轨迹数据的处理精度与质量。【方法】针对轨...【目的】随着智慧城市建设中信息技术的深度应用,GNSS轨迹数据呈爆炸式增长,但其轨迹生成过程易受信号干扰与传感器故障影响而产生噪声。本文旨在设计新型噪声识别与修复算法,以提升原始GNSS轨迹数据的处理精度与质量。【方法】针对轨迹噪声识别问题,本文提出基于密度矩阵的自适应DBSCAN算法,其具有超参数无关特性,可敏感捕获低幅值噪声点,同时避免连续转向点的误判。针对噪声修复问题,提出基于轨迹分段的函数构造式修复算法:首先采用道格拉斯-普克(Douglas-Peucker,DP)算法压缩轨迹数据实现分段;其次定位含噪声轨迹段,基于段内有效点构造拟合函数;最终依据相邻点时空属性修复噪声数据。相较于主流插值算法(如拉格朗日、牛顿、埃尔米特、线性、三次样条及最近邻插值),本方法通过规避全局特征依赖,显著保留了噪声点蕴含的局部信息特征。【结果】基于长春市1500名志愿者2024年8月19日—9月1日的原始GNSS轨迹数据,设计2组对比实验。第1组将新型识别算法与原始DBSCAN及其主流衍生算法(KANN-DBSCAN、BDT-ADBSCAN)进行对比。实验表明:新算法在轮廓系数(SC)、Calinski-Harabasz指数(CHI)、Da‐vies-Bouldin指数(DBI)3项指标均取得最优值,优化幅度分别为40.17%~381.80%、20.03%~235.18%、23.42%~79.53%。第2组实验对比新型修复算法与6类经典插值方法(拉格朗日、牛顿、埃尔米特、线性、三次样条、最近邻),结果显示:新算法在轨迹相似性度量指标(Dynamic Time Warping,DTW)上全面优于对比方法,整体优化幅度达43.18%~80.43%。【结论】本文提出的噪声识别与修复算法显著提升了原始GNSS轨迹的质量精度,可高效支撑大规模轨迹数据预处理任务,为时空轨迹挖掘研究提供高质量数据基础。展开更多
Carbon fibers(CFs)with notable comprehensive properties,such as light weight,high specific strength,and stiffness,have garnered considerable interest in both academic and industrial fields due to their diverse and adv...Carbon fibers(CFs)with notable comprehensive properties,such as light weight,high specific strength,and stiffness,have garnered considerable interest in both academic and industrial fields due to their diverse and advanced applications.However,the commonly utilized precursors,such as polyacrylonitrile and pitch,exhibit a lack of environmental sustainability,and their costs are heavily reliant on fluctuating petroleum prices.To meet the substantial market demand for CFs,significant efforts have been made to develop cost-effective and sustainable CFs derived from biomass.Lignin,the most abundant polyphenolic compound in nature,is emerging as a promising precursor which is well-suited for the production of CFs due to its renewable nature,low cost,high carbon content,and aromatic structures.Nevertheless,the majority of lignin raw materials are currently derived from pulping and biorefining industrial by-products,which are diverse and heterogeneous in nature,restricting the industrialization of lignin-derived CFs.This review classifies fossil-derived and biomass-derived CFs,starting from the sources and chemical structures of raw lignin,and outlines the preparation methods linked to the performance of lignin-derived CFs.A comprehensive discussion is presented on the relationship between the structural characteristics of lignin,spinning preparation,and structure-morphology-property of ligninderived CFs.Additionally,the potential applications of these materials in various domains,including energy,catalysis,composites,and other advanced products,are also described with the objective of spotlighting the unique merits of lignin.Finally,the current challenges faced and future prospects for the advancement of lignin-derived CFs are proposed.展开更多
文摘AIM:To assess the visual acuity and visual quality of cataract patients who received femtosecond laser-assisted cataract surgery(FLACS)and multifocal intraocular lens(MIOL)implantation with an improved polishing technique during a 1-year follow-up period.METHODS:This study included 74 eyes from 37 patients,comprising 17 males and 20 females,with a mean age of 51.74±7.80 years.Using a coin toss method,one eye per patient was randomly selected for improved anterior capsular polishing,while the other eye received standard irrigation/aspiration(I/A)polishing.The polishing group consisted of 37 eyes,including 21 right and 16 left eyes,while the control group comprised the contralateral fellow eyes of the same individuals in the polishing group.Visual acuity and quality of the patients were evaluated before surgery and at 1 wk,1,6,and 12 mo after surgery.The OPD-Scan III was utilized to assess high-order aberrations,while the optical quality analysis system(OQAS)was employed to evaluate modulation transfer function(MTF cutoff),Strehl ratio(SR),and objective scatter index(OSI)for the purpose of visual quality assessment.Paired t-tests and repeated measures analysis of variance(ANOVA)were utilized to compare the results,and the SNK-q post hoc test was applied to identify significant differences.RESULTS:The polishing group’s uncorrected distant visual acuity(UDVA)and uncorrected near visual acuity(UNVA)significantly improved 1-week post-surgery(all P<0.05).At 12-months,UDVA,UNVA,and corrected distant visual acuity(CDVA)were better than the control group(P<0.05).The MTF cutoff,SR,OSI,and high-order aberrations in the polishing group also showed significant improvements compared to the control group at 12 mo(P<0.05).CONCLUSION:The improved capsular polishing method has been demonstrated to effectively maintain visual acuity and visual quality in patients with MIOL after FLACS within 1 a.
文摘【目的】随着智慧城市建设中信息技术的深度应用,GNSS轨迹数据呈爆炸式增长,但其轨迹生成过程易受信号干扰与传感器故障影响而产生噪声。本文旨在设计新型噪声识别与修复算法,以提升原始GNSS轨迹数据的处理精度与质量。【方法】针对轨迹噪声识别问题,本文提出基于密度矩阵的自适应DBSCAN算法,其具有超参数无关特性,可敏感捕获低幅值噪声点,同时避免连续转向点的误判。针对噪声修复问题,提出基于轨迹分段的函数构造式修复算法:首先采用道格拉斯-普克(Douglas-Peucker,DP)算法压缩轨迹数据实现分段;其次定位含噪声轨迹段,基于段内有效点构造拟合函数;最终依据相邻点时空属性修复噪声数据。相较于主流插值算法(如拉格朗日、牛顿、埃尔米特、线性、三次样条及最近邻插值),本方法通过规避全局特征依赖,显著保留了噪声点蕴含的局部信息特征。【结果】基于长春市1500名志愿者2024年8月19日—9月1日的原始GNSS轨迹数据,设计2组对比实验。第1组将新型识别算法与原始DBSCAN及其主流衍生算法(KANN-DBSCAN、BDT-ADBSCAN)进行对比。实验表明:新算法在轮廓系数(SC)、Calinski-Harabasz指数(CHI)、Da‐vies-Bouldin指数(DBI)3项指标均取得最优值,优化幅度分别为40.17%~381.80%、20.03%~235.18%、23.42%~79.53%。第2组实验对比新型修复算法与6类经典插值方法(拉格朗日、牛顿、埃尔米特、线性、三次样条、最近邻),结果显示:新算法在轨迹相似性度量指标(Dynamic Time Warping,DTW)上全面优于对比方法,整体优化幅度达43.18%~80.43%。【结论】本文提出的噪声识别与修复算法显著提升了原始GNSS轨迹的质量精度,可高效支撑大规模轨迹数据预处理任务,为时空轨迹挖掘研究提供高质量数据基础。
基金National Natural Science Foundation of China,Grant/Award Numbers:32171717,32271814Natural Science Foundation of Tianjin Municipality,Grant/Award Numbers:24JCJQJC00030,22JCYBJC01560,23JCZDJC00630China Postdoctoral Science Foundation,Grant/Award Number:2023M740562。
文摘Carbon fibers(CFs)with notable comprehensive properties,such as light weight,high specific strength,and stiffness,have garnered considerable interest in both academic and industrial fields due to their diverse and advanced applications.However,the commonly utilized precursors,such as polyacrylonitrile and pitch,exhibit a lack of environmental sustainability,and their costs are heavily reliant on fluctuating petroleum prices.To meet the substantial market demand for CFs,significant efforts have been made to develop cost-effective and sustainable CFs derived from biomass.Lignin,the most abundant polyphenolic compound in nature,is emerging as a promising precursor which is well-suited for the production of CFs due to its renewable nature,low cost,high carbon content,and aromatic structures.Nevertheless,the majority of lignin raw materials are currently derived from pulping and biorefining industrial by-products,which are diverse and heterogeneous in nature,restricting the industrialization of lignin-derived CFs.This review classifies fossil-derived and biomass-derived CFs,starting from the sources and chemical structures of raw lignin,and outlines the preparation methods linked to the performance of lignin-derived CFs.A comprehensive discussion is presented on the relationship between the structural characteristics of lignin,spinning preparation,and structure-morphology-property of ligninderived CFs.Additionally,the potential applications of these materials in various domains,including energy,catalysis,composites,and other advanced products,are also described with the objective of spotlighting the unique merits of lignin.Finally,the current challenges faced and future prospects for the advancement of lignin-derived CFs are proposed.