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Effects of higher-order aberrations on contrast sensitivity in normal eyes of a large myopic population

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International Journal of Ophthalmology(English edition) 2017年第9期10卷 1407-1411页

作者： Peng-Fei zhao Shi-Ming li Jing Lu Hong-Min Song Jing zhang Yue-Hua zhou Ning-li Wang Ophthalmic Center Beijing Tongren Hospital Capital Medical University Beijing Ophthalmology and Visual Sciences Key Lab Department of Ophthalmology Affiliated Hospital of Hebei Medical University College of Applied Arts and Science Beijing Union University

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）***：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 ***,ocular HOAs were measured for a 6.0 mm pupil with a Hartmann-Shack wavefront ***：In the study,the subjects with an average spherical equivalent of-4.86±2.07 D were *** decreased from the third to the sixth order aberrations with predominant aberrations of third-order coma,trefoil and fourth-order spherical *** 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 *** high spatial frequencies,CS decreased with increasing z3-3and increased with increasing ***：At a large pupil size of 6.0 mm,the thirdorder aberrations,but not the total aberrations,are the main factors affecting *** coma is negatively correlated with CS.

关键词： myopia contrast sensitivity higher-orderaberrations coma spherical aberration

Mechanical Behaviors of Anchorage Interfaces in Layered Rocks with Fractures under Axial Loads

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Journal of Earth Science 2023年第2期34卷 354-368页

作者： Yan Wang Changdong li zhilan Cai Guoqiang zhu Jiaqing zhou Wenmin Yao Faculty of Engineering China University of GeosciencesWuhan 430074China Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan 430074China School of Civil Engineering Zhengzhou UniversityZhengzhou 450001China

Rock bolts are widely employed as an effective and efficient reinforcement method in geotechnical *** composite structures formed by hard rock and weak rock are often encountered in practical ***,the spatial structure of the rock mass has a direct influence on the effect of the anchorage *** investigate the impact of rock mass structure on the mechanical characteristics of anchorage interfaces,pull-out tests on reinforced specimens with different mudstone thicknesses and fracture dip angles are *** experimental results indicate that the percentage of mudstone content and fracture dip angle have a significant influence on the pullout load of the samples.A weaker surrounding rock results in a lower peak load and a longer critical anchorage length,and vice *** results also show that 70%mudstone content can be considered a critical condition for impacting the peak ***,the percentage of mudstone content has a limited influence on the variation in the peak load when it exceeds 70%.Optical fiber deformation results show that compared to the rock mass with fracture dip angles of 0°and 60°,the rock mass with a fracture dip angle of 30°has a more uniformly distributed force at the anchorage *** the fracture dip angle exceeds 60°,the dip angle is no longer a key indicator of peak *** accuracy of the experimentally obtained load-displacement curves is further verified although numerical simulation using the discrete element method.

关键词： layered rocks grouted rockbolts grout/rock interface distributed optical fiber mechanical behavior

Revisiting the size of nonspherical particles recorded by optical array probes with a new method based on the convex hull

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Atmospheric and Oceanic Science Letters 2022年第3期15卷 1-5页

作者： Rong zhang Xu zhou Hongyu li Hanchao li Lei Wei Yang Gao Qiang Xia Xiangyu Wang Key Laboratory for Cloud Physics of China Meteorological Administration BeijingChina State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijingChina Weather Modification Centre China Meteorological AdministrationBeijingChina Inner Mongolia Institute of Meteorological Sciences&Inner Mongolia Key Laboratory of Manual Weather Modification HohhotChina Beijing Weather Modification Center BeijingChina China Huayun Meteorological Technology Group Corporation BeijingChina Weather Modification Center in Eastern Inner Mongolia TongliaoChina

In recent years,the Cloud Imaging Probe(CIP)and Precipitation Imaging Probe(PIP)produced by Droplet Measurement Technologies(DMT)have been introduced by a number of meteorological research and operation centers in *** supporting software provided by DMT,i.e.,PADS(Particle Analysis and Display System),cannot output detailed information on each individual particle,which definitely limits the in-depth utilization of cloud and precipitation particle image data in *** this paper,particle-by-particle information was extracted by decompressing the CIP and PIP original particle image data,based on which a new definition of the dimension for nonspherical particles is proposed by using the area of the convex hull enclosing a particle to obtain the equivalent diameter of a circle with equal *** on the data detected during one flight in Inner Mongolia,the particle size distribution obtained using the new particle size definition and that used by the other four existing definitions are *** results show that the particle number concentration calculated using different particle size definitions can vary by up to an order of *** result obtained based on the new particle size definition is closest to that calculated with the area-equivalent diameter definition.

关键词： Cloud and precipitation particles Particle image Particle size Particle size distribution

Cytological, physiological, and transcriptomic analyses of golden leaf coloration in Ginkgo biloba L

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Horticulture Research 2018年第1期5卷 797-810页

作者： Wei-xing li Shun-bo Yang zhaogeng Lu zhi-chong He Yun-ling Ye Bei-bei zhao li Wang Biao Jin College of Horticulture and Plant Protection Yangzhou UniversityYangzhou225009China College of Resource and Environment Xizang Agriculture and Animal Husbandry CollegeTibet860000China

Ginkgo biloba is grown worldwide as an ornamental plant for its golden leaf ***,the regulatory mechanism of leaf coloration in *** remains ***,we compared *** gold-colored mutant leaves and normal green leaves in cytological,physiological and transcriptomic *** found that chloroplasts of the mutant were fewer and smaller,and exhibited ruptured thylakoid membranes,indistinct stromal lamellae and irregularly arranged *** experiments also showed that the mutant had a lower chlorophyll,lower flavonoid and higher carotenoid contents(especially lutein).We further used transcriptomic sequencing to identify 116 differentially expressed genes(DEGs)and 46 transcription factors(TFs)involved in chloroplast development,chlorophyll metabolism,pigment biosynthesis and *** these,the chlorophyll biosynthesis-related PPO showed down-regulation,while chlorophyll degradation-related NYC/NOL had up-regulated expression in mutant leaves.z-ISO,zDS,and LCYE,which are involved in carotenoid biosynthesis were *** real-time PCR(RT-qPCR)further confirmed the altered expression levels of these genes at three *** alteration of PPO and NYC/NOL gene expression might affect chlorophyll biosynthesis and promote degradation of chlorophyll b to chlorophyll a,while the up-regulated genes z-ISO,zDS and LCYE enhanced carotenoid ***,changes in the ratio of carotenoids to chlorophylls were the main factors driving the golden leaf coloration in the mutant ***.

关键词： metabolism golden fir

Synergistic effects of Mg-substitution and particle size of chicken eggshells on hydrothermal synthesis of biphasic calcium phosphate nanocrystals

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Journal of Materials Science & Technology 2020年第1期36卷 27-36页

作者： Wei Cui Qibin Song Huhu Su zhiqing Yang Rui Yang Na li Xing zhang Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China Department of Plastic Surgery Shengjing Hospital of China Medical UniversityShenyang 110004China

Magnesium(Mg^2+))ion plays important roles in biomineralization of bone,teeth and calcium carbonate ***,chicken eggshells mainly comprising of Mg-calcite nanocrystals(Mg/(Mg+Ca)2.0 mol.%)were used to fabricate biphasic calcium phosphate(BCP),a mixture of hydroxyapatite(HA)and p-tricalcium phosphate(p-TCP)nanocrystals,through hydrothermal reactions at 200℃for 24 *** results indicated thatβ-TCP nanocrystals formed through the ion-exchange reactions of Mg-calcite,while HA nanocrystals were mainly produced by dissolution-reprecipitation reactions on the surfaces of eggshell samples in the hydrothermal *** substitution in calcite resulted in formation ofβ-TCP nanocrystals instead of HA crystals through ion-exchange *** samples with different compositions(28.6-77.8 wt.%β-TCP)were produced by controlling particle sizes of eggshells for hydrothermal *** larger particles lead to the larger proportion ofβ-TCP in the BCP ***,Mg substitution and particle size had synergetic effects on the hydrothermal synthesis of BCP using chicken eggshells through balance of ion-exchange and dissolution-reprecipitation *** culture results showed that the BCP products were non-cytotoxic to MC3 T3-E1 cells,which may be used for bone substitute materials in future.

关键词： Hydrothermal reactions Ion-exchange Dissolution-reprecipitation Nanocrystals Biphasic calcium phosphate Bone substitute materials

Source apportionment of PM_(2.5)and visibility in Jinan,China

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Journal of Environmental Sciences 2021年第4期33卷 207-215页

作者： Mengtian Cheng Guiqian Tang Bo Lv Xingru li Xinrui Wu Yiming Wang Yuesi Wang Key Laboratory for Semi-Arid Climate Change of Ministry of Education College of Atmospheric SciencesLanzhou UniversityLanzhou 730000China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Jinan Ecological and Environment Monitoring Center of Shandong Province Jinan 250000China Capital Normal University Beijing 100048China

Atmospheric extinction is impacted by the chemical composition of *** better understand the chemical composition of PM_(2.5)(particles with diameters of less than 2.5μm)and its relationship with extinction,one-month sampling campaigns were carried out in four different seasons from 2013 to 2014 in Jinan,*** seasonal average concentrations of PM_(2.5)were 120.9(autumn),156.6(winter),102.5(spring),and 111.8μg/m^(3)(summer).The reconstructed PM_(2.5)chemical composition showed that sulfate,nitrate,chlorine salt,organic matter(OM),mineral dust,elemental carbon(EC)and others accounted for 25%,14%,2%,24%,22%,3%and 10%,*** relationship between the chemical composition of PM_(2.5)and visibility was reconstructed by the IMPROVE method,and ammonium sulfate,ammonium nitrate,OM and EC dominated the *** main sources were resolved for PM_(2.5),including secondary particles,coal combustion,biomass burning,industry,motor vehicle exhaust,soil dust and cooking,which accounted for 37%,21%,13%,13%,12%,3%and 1%,*** contributions of different sources to visibility were similar to those to PM_(2.5).With increasing severity of air pollution,the contributions of secondary particles and coal combustion increased,while the contribution of motor vehicle exhaust *** results showed that coal combustion and biomass burning were still the main sources of air pollution in Jinan.

关键词： PM_(2.5) Jinan Source apportionment Extinction

MiR-430 Can Affect the Mesoderm Formation and Metamorphosis of Paralichthys olivaceus by Targeting lefty Gene

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Journal of Ocean University of China 2020年第2期19卷 409-416页

作者： li Rui WANG zhenwei SUN Minmin PENG Meiting QI Jie WANG zhigang Key Laboratory of Marine Genetics and Breeding Ministry of Education College of Marine Life SciencesOcean University of China

MiR-430 is a non-coding small RNA that participates in early embryonic development by acting on the Nodal signaling *** functions in Paralichthys olivaceus(***),however,remain *** this study,through biological information technology,we hypothesized lefty was the target gene of *** is a divergent member of the transforming growth factor-β(TGF-β)superfamily,and is involved in regulating left-right patterning as an antagonist of the Nodal signaling *** study the relationship between miR-430 and lefty gene,miR-430 and fluorescent expression vector were transfected into embryo *** results showed that miR-430 has important effects on early embryonic *** can inhibit the expressions of lefty and other genes related to Nodal signaling ***,the expression of miR-430 was involved in the metamorphosis of *** study clarifies the function of miR-430 in ***,which will be helpful for further research on the interactions between miR-430 and the Nodal signaling pathway.

关键词： miR-430 lefty Nodal signal pathway Paralichthys olivaceus

Comparative Assessment on Microstructure and Properties of in-situ TiC+Ti_(5)Si_(3)Reinforced TiAl-Sn-zr Matrix Composites by Spark Plasma Sintering and Argon Protected Sintering

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Journal of Wuhan University of Technology(Materials Science) 2023年第1期38卷 199-205页

作者：姚辉许晓静 CAI Chengbin li Chen CHEN Fenghua liU Yangguang XIAO Yishui Institute for Advanced Manufacturing and Modern Equipment Technology Jiangsu UniversityZhenjiang 212013China

The effects of SiC particles(SiCp)on high temperature oxidation behavior of titanium matrix composites(TMCs)under different powder metallurgy processes were *** situ Ti C+Ti_(5)Si_(3)reinforced titanium matrix composites were prepared by discharge plasma sintering(SPS)and argon protective sintering(APS).The results show that the two processes have a negligible effect on the composition and hardness of the samples,but the hardness of the two samples is significantly improved by adding *** apparent porosity of SPS process is obviously smaller than that of APS process,whereas,the apparent porosity increases slightly with the addition of *** oxide layer thickness and mass gain of the samples obtained by SPS process are smaller than those obtained by APS *** oxide thickness and mass gain of both processes are further reduced by adding *** SPS composites showed the best high temperature oxidation ***,TMCs with Si Cp by SPS can effectively improve the high-temperature oxidation behavior of the materials.

关键词： powder metallurgy titanium matrix composites High-temperature oxidation TiC and Ti_(5)Si_(3) Ti-Al-Sn-zr

Comparative Analysis of the Characteristics of Rainy Season Raindrop Size Distributions in Two Typical Regions of the Tibetan Plateau

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Advances in Atmospheric Sciences 2022年第7期39卷 1062-1078页

作者： Gaili WANG Ran li Jisong SUN Xiangde XU Renran zHOU liping liU State Key Laboratory of Severe Weather Chinese Academy of Meteorological ScienceBeijing 100081China

Mêdog and Nagqu are two typical regions of the Tibetan Plateau with different geographical locations and climate *** differences may lead to discrepancies in the raindrop size distributions(DSDs)and precipitation microphysical processes between the two *** paper investigates discrepancies in the DSDs using disdrometer data obtained during the rainy season in Mêdog and *** DSD characteristics are studied under five different rainfall rate categories and two precipitation types(stratiform and convective).For the total datasets,the number concentrations of drops with diameters D>0.6(Dlized gamma distributions of the averaged DSDs for the five rainfall rate categories show that Nagqu has a larger(lower)mass-weighted mean diameter D_(m)(normalized intercept parameter,lgNw)than Mêdog *** difference in D_(m)between Nagqu and Mêdog increases with the rainfall *** clusters in Nagqu could be identified as continental-like,while convective precipitation in Mêdog could be classified as *** relationships between the shape factorμand slope parameterΛof the gamma distribution model,the radar reflectivity z,and the rainfall rate R are also ***,the possible causative mechanism for the notable DSD variation between the two regions during the rainy season is illustrated using reanalysis data and automated weather station *** rain processes are mainly responsible for the lower concentrations of larger drops observed in Nagqu,whereas warm rain prevails in Mêdog,producing abundant small drops.

关键词： raindrop size distribution Tibetan Plateau continental-like maritime-like warm rain cold rain