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Clinical outcomes of small incision lenticule extraction versus femtosecond laser-assisted LASIK for myopia: a Meta-analysis

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International Journal of Ophthalmology(English edition) 2017年第9期10卷 1436-1445页

作者： huan yan Li-yan Gong Wei huang yan-Li Peng Department of Ophthalmology the Second Affiliated Hospital of Chongqing Medical University Chongqing Medical University Department of Ophthalmology Chongqing Aier-Mega Eye Hospital Aier Eye Hospital Group Aier School of Ophthalmology Central South University

AIM：To evaluate the possible differences in visual quality between small incision lenticule extraction（SMILE）and femtosecond laser in situ keratomileusis（FS-LASIK）for ***：A Meta-analysis was *** were from previously reported comparative studies treated with SMILE versus *** Pub Med,EMBASE,Cochrane,Web of Science and Chinese databases（*** and CNKI）were searched in *** 2016 using Rev Man 5.1 version *** differences in visual acuity,aberration and biomechanical effects within six months postoperatively were ***-seven studies including 4223 eyes were ***：No significant differences were observed between SMILE and FS-LASIK in terms of the proportion of eyes that lost one or more lines of corrected distance visual acuity after surgery（P=0.14）,the proportion of eyes achieving an uncorrected distance visual acuity of 20/20or better（P=0.43）,the final refractive spherical equivalent（P=0.89）,the refractive spherical equivalent within±1.00diopter of the target values（P=0.80）,vertical coma（P=0.45）and horizontal coma（P=0.06）.Compared with the FSLASIK group,total higher-order aberration（P〈0.001）and spherical aberration（P〈0.001）were higher and the decrease in corneal hysteresis（P=0.0005）and corneal resistance factor（P=0.02）were lower in the SMILE ***：SMILE and FS-LASIK are comparable in efficacy,safety and predictability for correcting ***,the aberration in the SMILE group is superior to that in the FS-LASIK group,and the loss of biomechanical effects may occur less frequently after SMILE than after FS-LASIK.

关键词： Meta-analysis small incision lenticuleextraction femtosecond laser in situ keratomileusis myopia

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The effect of single-horn glaze ice on the vortex structures in the wake of a horizontal axis wind turbine

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Acta Mechanica Sinica 2015年第1期31卷 62-72页

作者： Zhe-yan Jin qiao-Tian Dong Zhi-Gang yang School of Aerospace Engineering and Applied Mechanics Tongji University School of Automotive Studies Tongji University Shanghai Automotive Wind Tunnel Center

The present study experimentally investigated the effect of a simulated single-horn glaze ice accreted on ro- tor blades on the vortex structures in the wake of a hori- zontal axis wind turbine by using the stereoscopic particle image velocimetry （Stereo-PIV） technique. During the ex- periments, four horizontal axis wind turbine models were tested, and both ＂free-run＂ and ＂phase-locked＂ Stereo-PIV measurements were carried out. Based on the ＂free-run＂ measurements, it was found that because of the simulated single-horn glaze ice, the shape, vorticity, and trajectory of tip vortices were changed significantly, and less kinetic en- ergy of the airflow could be harvested by the wind turbine. In addition, the ＂phase-locked＂ results indicated that the pres- ence of simulated single-horn glaze ice resulted in a dramatic reduction of the vorticity peak of the tip vortices. Moreover, as the length of the glaze ice increased, both root and tip vortex gaps were found to increase accordingly.

关键词： Stereo-PIV Single-horn glaze ice. Tip vorticesRoot vortices Wind turbine icing

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A dynamical transition of a chain of charged particles in a 2D substrate potential

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Communications in Theoretical Physics 2020年第7期72卷 116-122页

作者： Xiao-Ping Yuan Li-yan qiao Xia huang Information Engineering School Hangzhou Dianzi UniversityHangzhou 310018China Department of Physics Hangzhou Dianzi UniversityHangzhou 310018China School of Mathematics and Physics North China Electric Power UniversityBeijing 102206China

The transport of a chain of charged particles with a transverse degree of freedom is investigated in a 2D asymmetric ***,the energy of the periodic driving force is converted into motion in the vertical *** analysis exhibits a transition from stick-slip motion to periodic *** chain velocity can be controlled to an optimized value by adjusting system parameters,such as the amplitude and frequency of the periodic *** existence of a resonance platform indicates resonance between the motion of the chain and the periodic force as coupling strength increases *** atomic configuration and the transverse degree of freedom also play key roles in the control.

关键词： collective transport driven Frenkel–Kontorova model cooperative ratchet

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Hemoglobin within normal range is negatively related to hemoglobin A1c in a nondiabetic American population aged 16 years and older

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World Journal of Diabetes 2022年第3期13卷 251-259页

作者： Xiao-Fang Bai huan Wang qiao-Ling Zhao Department of Ultrasound Medicine The First Affiliated HospitalXi'an Jiaotong UniversityXi'an 710061Shannxi ProvinceChina Department of Pain Medicine The First Affiliated HospitalXi'an Jiao tong UniversityXi'an 710061Shannxi ProvinceChina

BACKGROUND Protein glycosylated hemoglobin,hemoglobin A1c(HbA1c)binds hemoglobin(Hb)in red blood cells to blood ***,the relationship between Hb and HbA1c remains *** To elucidate their relationship in a nondiabetic population aged≥16 years in the United States,using data from the 1999-2018 National Health and Nutrition Examination *** This study was based on data from 44560 adults aged≥16 years,excluding those with *** relationship was estimated using a multivariate *** also used piecewise linear regression for subgroup analysis based on age and sex stratification and analysis of the threshold effects of Hb on *** Hb and HbA1c levels were negatively correlated in the unadjusted model(β=-0.01;95%CI:-0.01,-0.01).The correlation was significantly negative when the regression model was minimally regulated and stratified by age and sex,and remained negative when the model was further regulated(more than 10%)to identify covariates with the HbA1c level influence *** subgroup analyses based on age and sex stratification,the association remained negative when the covariates were controlled.A nonlinear relationship was observed between them when the Hb levels reached the tipping point(13.2 g/dL)(adjusted odds ratio,-0.04;95%CI:-0.05,-0.03)and when the Hb levels exceeded 13.2 g/dL(adjusted odds ratio,-0.10;95%CI:-0.10,-0.09).CONCLUSION Our study shows that normal Hb levels are negatively correlated with HbA1c in nondiabetic Americans aged≥16 years.

关键词： Haemoglobin Glycosylated haemoglobin Diabetes National Health and Nutrition Examination Survey

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New design for multi-crystal data collection at SSRF

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Nuclear Science and Techniques 2018年第2期29卷 48-56页

作者： Bing Li Sheng huang Qiang-yan Pan Min-Jun Li huan Zhou Qi-Sheng Wang Feng Yu Bo Sun Jian-qiao Chen Jian-Hua He Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

Data collection with microcrystals at synchrotron radiation facilities is challenging because it is difficult to harvest and locate microcrystals. Moreover,microcrystals are sensitive to radiation damage; thus, typically, a complete data set cannot be obtained with a single microcrystal. Herein, we report a new method for data collection with multiple microcrystals having a crystal size ranging from 1 to 30 lm. This method is suitable for not only low-temperature(100 K) data collection but also room-temperature data collection. Thin Kapton membranes were used to capture multiple crystals simultaneously. The microcrystals were visible under an optical microscope and easily located because the membrane was transparent and sufficiently thin. The film was fixed to a bracket that was prepared using a three-dimensional printer. The bracket was fixed on a magnetic base via screwing and employed by the goniometer system for data collection. Multiple data sets of fatty acid-binding protein 4(FABP4) and lysozyme microcrystals were collected using this novel designed device. Finally, the structures of protein FABP4 and lysozyme were obtained from these data via the molecule replacement method. The data statistics reveal that this method provides a comparable result to traditional methods such as a nylon loop.

关键词： Kapton membrane Microcrystals Multicrystal data collection Protein structure

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Significant influence of trace Li on the mechanical properties, corrosion behavior, and antibacterial properties of biodegradable Zn–4Cu alloys

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Journal of Materials Science & Technology 2023年第20期151卷 245-257页

作者： Shiyu huang Heng Liu yanjing Su Lijie qiao Yu yan Beijing Advanced Innovation Center for Materials Genome Engineering Corrosion and Protection CenterInstitute for Advanced Materials and TechnologyUniversity of Science and TechnologyBeijing 100083China

In this work,trace Li was introduced to strengthen Zn–4Cu *** results indicated that trace amounts of Li contributed to a significant increase in strength,resulting in an acceptable loss of elongation at ***,Li in the form of LiZn_(4) led to more intensive galvanic corrosion,which accelerated the early corrosion *** release of a large amount of Zn^(2+),caused by the addition of Li,affected the phase composition of the main Zn-containing corrosion ***,the inhibition effect of the alloy on Staphylococcus aureus(***)was enhanced by the addition of 0.02 wt.%Li.

关键词： Microalloying Zn-Cu alloy LiZn_(4)/Zn pairs Biodegradable mechanism SKPFM

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Upconversion Luminescence of SrTiO3：Er^3＋ Ultrafine Powders Produced by 785 nm Laser

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Chinese Journal of Chemical Physics 2008年第3期21卷 233-238页

作者： Hai Guo yan-min qiao Ju-fang Zheng Lei-hong Zhao Department of Physics Zhejiang Normal University Jinhua 321004 China Zhejiang Key Laboratory for Reactive Chemistry on 5olicl Surfaces Institute of Physical Chemistry Zhejiang Normal University Jinhua 321004 China

Er^3＋ doped SrTiO3 ultrafine powders were prepared by solid state reaction in a molten NaCl flux. The structural properties were characterized by X-ray diffraction, field emission scanning electron microscopy, and Fourier transform infrared spectroscopy. The Stokes emission spectra of Er^3＋ in SrTiO3：Er^3＋ ranging from green to near infrared region were investigated under 514.5 nm laser excitation. The green and red upconverted luminescence spectra of Er^3＋ were measured under excitation into the 419/2 level by 785 nm laser. The upconversion mechanisms were studied in detail through laser power dependence and Er^3＋ ion concentration dependence of upconverted emissions, and results show that excited state absorption and energy transfer process are the possible mechanisms for the upconversion. The upconversion properties indicate that SrTiO3：Er^3＋ may be used in upconversion phosphors.

关键词： SrTiO3 Upconversion luminescence Excited state absorption Energy transfer

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Chemical characteristics of fine particulate matter emitted from commercial cooking

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Frontiers of Environmental Science & Engineering 2016年第3期10卷 559-568页

作者： Bing PEI Hongyang CUI huan LIU Naiqiang yan School of Environmental Science and Engineering Shanghai Jiao Tong University Shanghai 200040 China Shanghai Environmental Monitoring Center Shanghai 200030 China Ministry of Education Key Laboratory for Earth System Modeling Center for Earth System Science Tsinghua University Beijing 100084 China School of Environment State Key Joint Laboratory of Environment Simulation and Pollution Control (SKLESPC) Tsinghua University Beijing 100084 China

The chemical characteristics of fine particulate matter （PM2.5） emitted from commercial cooking were explored in this study. Three typical commercial restau- rants in Shanghai, i.e., a Shanghai-style one （SHS）, a Sichuan-style one （SCS） and an Italian-style one （ITS）, were selected to conduct PM2.5 sampling. Particulate organic matter （POM） was found to be the predominant contributor to cooking-related PM2.5 mass in all the tested restaurants, with a proportion of 69.1% to 77.1%. Specifically, 80 trace organic compounds were identified and quantified by gas chromatography/mass spectrometry （GC/MS）, which accounted for 3.8%-6.5% of the total PM2.5 mass. Among the quantified organic compounds, unsaturated fatty acids had the highest concentration, followed by saturated fatty acids. Comparatively, the impacts of other kinds of organic compounds were much smaller. Oleic acid was the most abundant single species in both SCS and ITS. However, in the case of SHS, linoleic acid was the richest one. ITS produced a much larger mass fraction of most organic species in POM than the two Chinese cooking styles except for monosaccharide anhy-drides and sterols. The results of this study could be utilized to explore the contribution of cooking emissions to PM2.5 pollution and to develop the emission inventory of PM2.5 from cooking, which could then help the policymakers design efficient treatment measures and control strategies on cooking emissions in the future.

关键词： commercial cooking PM2.5 chemical char- acteristics organic matter

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Lifecycle of cobalt-based alloy for artificial joints:From bulk material to nanoparticles and ions due to bio-tribocorrosion

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Journal of Materials Science & Technology 2020年第11期42卷 98-106页

作者： Zhongwei Wang Yu yan yang Wang yanjing Su Lijie qiao Beijing Advanced Innovation Center for Materials Genome Engineering Corrosion and Protection CenterKey Laboratory for Environmental Fracture(MOE)University of Science and Technology BeijingBeijing 100083China College of Materials Science and Engineering Chongqing University of TechnologyChongqing 400054China Corrosion and Protection Center Advanced Institute for Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China

The release of debris and ions from metallic artificial joints during bio-tribocorrosion posed a severe threat to patient *** this work,the lifecycle of a Co Cr Mo alloy was presented by investigating the subsurface microstructure transformation *** results showed that the originally coarse grains changed to nano-grains(NGs)on the top region of the alloy,and nanoparticles(NPs)were torn off the surface,which were then blocked by the *** agglomerated alloy NPs contained in the tribofilm transformed into debris after being removed from the alloy *** majority of the torn-off NPs were corroded and released ions into solution due to their high chemical activities.

关键词： Cobalt-based alloy Artificial joints Wear mechanism Bio-t Ribocorrosion TEM

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基于k-center聚类和最近邻中心的公平数据汇总

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西华师范大学学报（自然科学版） 2025年第1期46卷 95-103页

作者：何艳黄巧玲郑伯川西华师范大学数学与信息学院四川南充637009 西华师范大学计算机学院四川南充637009

公平数据汇总是指从每种数据类别中选择有代表性的子集,且满足公平性要求。在大数据时代,每种类别的数据都是海量的,因此公平数据汇总研究具有非常重要的现实意义。为了使公平数据汇总的数据点更具有代表性,提出了基于k-center聚类和最... 详细信息

公平数据汇总是指从每种数据类别中选择有代表性的子集,且满足公平性要求。在大数据时代,每种类别的数据都是海量的,因此公平数据汇总研究具有非常重要的现实意义。为了使公平数据汇总的数据点更具有代表性,提出了基于k-center聚类和最近邻中心的公平数据汇总算法。算法主要包括2个基本步骤:(1)通过k-center聚类,将k个簇中心作为当前汇总结果;(2)选择满足公平约束的原簇中心的最近邻点作为新簇中心。由于更新簇中心时选择的是原簇中心的最近邻点,因此相对随机选择的数据点,最近邻点更具有代表性,是除原始簇中心外的次优代表点。同时,寻找最近邻点作为新的簇中心能最大限度减少公平代价。在2个模拟数据集和6个UCI真实数据集上的对比实验结果表明,所提出的算法在近似因子和公平代价方面都优于对比算法,说明所提出的算法获得的数据汇总更具有代表性。

关键词：最近邻点 k-center聚类数据汇总公平约束

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