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Comparison of age-related changes between corneal and ocular aberration in young and mid-age myopic patients

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International Journal of Ophthalmology(English edition) 2011年第3期4卷 286-292页

作者： feng-Ju Zhang, meng-meng Wang Beijing Tongren Eye Center Beijing Tongren Hosptial Capital Medical University Beijing 100730 China Department of Ophthalmology Gongren Hospital of Tangshan City Tangshan 063000 Hebei Province China Department of Ophthalmology 1 [st]Hospital of Dalian Medical University Dalian 116011 Liaoning Province China Department of Ophthalmology People Hosipital of Xinjiang Uygur Autonomous Region Urumqi 830001 Xinjiang Uygur Autonomous Region China

AIM: To study the dynamic character of aberration between the cornea and the ocular with aging, and to evaluate the symmetry of the aberrations between right and left eye in order to supply the data for clinic to do the refractive surgery reasonably. METHODS: This is a comparative case series study. 82 normal cases (164 eyes) including 37 females (74 eyes) and 45 males (90 eyes) were recruited through the routine examinations,Topolyzer and wavefront analysis. The average age was 25.9 +/- 5.0 years old (range 18 to 49 years old), and the mean spherical equivalent (SE) is -3.82 +/- 2.21D (range -1.00 to -6.00D). The changes of aberrations regarding age, the relationship between anterior corneal and total aberrations were analyzed,as well as the symmetry between right and left eyes by using Zernike terms. RESULTS: The Z (3) (1), RMS3 of corneal aberrations, Z (3) (1), Z (4) (0) RMS3 and RMS4 of ocular aberrations had a positive correlation with age. The zernike terms both in corneal and whole eye were significantly correlated between right and left eyes. COnCLUSIOn: The corneal horizontal coma, ocular horizontal coma and ocular spherical aberrations become to increase at the age of more than 40 years old. The dynamic change of aberration with aging, balance between corneal and ocular, and the symmetric character between left eye and right eye should be designed carefully in the treatment nomogram before the refractive surgery.

关键词： cornea ocular aberration age change character

考虑社会学习的产品定价和质量决策——参照效应与消费者异质性的影响

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管理工程学报 2025年第1期39卷 196-213页

作者：李锋魏莹华南理工大学工商管理学院暨南大学管理学院广州品牌创新发展研究基地

消费者通过观察电商平台的产品评论信息更新对产品质量的感知,这种社会学习行为直接影响消费者的购买决策以及企业的产品质量和价格策略。本文考虑消费者购买过程中的两种参照效应:学习参照和体验参照。前者指购买前消费者关于产品质量... 详细信息

消费者通过观察电商平台的产品评论信息更新对产品质量的感知,这种社会学习行为直接影响消费者的购买决策以及企业的产品质量和价格策略。本文考虑消费者购买过程中的两种参照效应:学习参照和体验参照。前者指购买前消费者关于产品质量的预判对社会学习的效果产生参照效应;后者指学习更新后的质量感知对于消费者购买后的质量体验形成参照。本文构建多智能体模型,以产品评论信息为载体,研究消费者社会学习中的参照效应以及消费者异质性对企业产品质量和价格决策的影响,之后进一步讨论了平台信息策略和企业区别定价策略的效果。研究发现:首先,社会学习中的学习参照效应导致企业降低价格、提高质量且从中受损;而体验参照效应提高用户评价信息均值和集中度,从而使企业提高定价且从中受益。总体而言,社会学习行为有利于企业但参照效应对企业不利。其次,消费者对于产品质量感知的差异程度影响社会学习和参照效应的效果。当质量感知差异程度较低时,考虑参照效应的社会学习行为对企业的价格和质量决策的影响不明显;当感知差异增大到一定程度时,会显著降低企业的价格并影响质量决策。再次,企业从消费者质量先验感知差异程度中受益,但受损于质量后验体验的差异程度。和统一价格策略相比,区别定价能够提高企业收益,但对质量决策影响甚微。最后,平台与卖方共享消费者信息可以减少企业的机会损失,而与买方共享分类统计信息对企业决策影响不大。研究结果同时提供了丰富的管理启示。

关键词：社会学习参照效应质量区别定价智能体建模与仿真

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Attractor for the Extensible Beam Equation with nonlocal Weak Damping on Time–Dependent Space

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1115-1126页

作者： Chun Xiang ZHAO feng Juan meng Institute of Applied System Analysis Jiangsu UniversityZhenjiang 212013P.R.China School of Mathematics and Physics Jiangsu University of TechnologyChangzhou 213001P.R.China

In this article,we consider the long-time behavior of extensible beams with nonlocal weak damping:ε(t)u_(tt)+Δ^(2)u-m(‖▽u‖^(2))Δu+‖u_(t)‖^(p_(u_(t)))+f(u)=h,whereε(t)is a decreasing function vanishing at *** the theory of process on time-dependent spaces,we investigate the existence of the time-dependent attractor by using the Condition(C_(t))method and more detailed *** results obtained essentially improve and complete some previous works.

关键词： Time-dependent attractor extensible beams equation nonlocal weak damping

Asymmetric Catalysis with Chiral Frustrated Lewis Pairs

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Chinese Journal of Chemistry 2020年第6期38卷 625-634页

作者： Wei meng Xiangqing feng Haifeng Du Beijing national Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The chemistry of frustrated Lewis pairs(FLPs)provides the most important approach for the metal-free hydrogenation and *** progress has been achieved in this area for the past *** promising results have also been *** perspective article mainly focuses on the recent advances for the synthesis of chiral Lewis acidic boranes in category of three protocols,1)hydroboration of chiral internal alkenes with Piers'borane HB(C6F5)2;2)in situ hydroboration of chiral alkenes or alkynes without any purification;3)and substitution reaction of(C6F5)nBCl3-n with chiral organometallic reagents,as well as their applications in the metal-free asymmetric hydrogenations and hydrosilylations.

关键词： chiral hydrogenation Chiral

Chiral Dienes: From Ligands to FLP Catalysts

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Chinese Journal of Chemistry 2022年第9期40卷 1109-1116页

作者： Xiangqing feng Wei meng Haifeng Du Beijing national Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Olefins are very easily accessible compounds which are both popular substrates in synthetic chemistry and good ligands in the organometallic *** dual character makes olefins a rich source of chiral ligands and catalysts for asymmetric ***,we willbriefly summarize our studies on the development of chiral diene ligands for transition-metal catalyzed asymmetric reactions and chiral FLP catalysts for asymmetric metal-free hydrogenations and *** acyclic chiral diene ligands as well as P/olefin and S/olefin hybrid ligands were developed for Rh or Pd-catalyzed asymmetric *** these ligands in hand,we further put forward a novel strategy for acquiring chiral FLP catalysts via the in situ hydroboration of chiral dienes with Piers'*** catalysts proved to be highly ffective for asymmetric metal-free hydrogenations and hydrosilylations of imines,ilyl enol ethers,ketones,and aromatic n-heterocycles.

关键词： Asymmetric catalysis Chiral dienes Frustrated Lewis pair Conjugated addition Hydrogenation

Macroscopic Supramolecular Assembly and Its Applications

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Chinese Journal of Polymer Science 2018年第3期36卷 306-321页

作者： meng-Jiao Cheng Qian Zhang feng Shi State Key Laboratory of Organic—Inorganic Composites&Beijing Advanced Innovation Center for Soft Matter Science and Engineering&Beijing Laboratory of Biomedical Materials Beijing University of TechnologyBeijing 100029China

Macroscopic supramolecular assembly(MSA)has been a recent progress in supramolecular *** mainly focuses on studies of the building blocks with a size bey.nd ten micrometers and the non-covalent interactions between these interactive building blocks to form ordered *** is essential to realize the concept of"self-assembly at all scales"by bridging most supramolecular researches at molecular level and at macroscopic *** review summaries the development of MSA,the basic design principle and related strategies to achieve MSA and potential ***,we try to elucidate the correlations and differences between"macroscopic assembly"and MSA based on intermolecular interactions;the design principle and the underly.ng assembly mechanism of MSA are proposed to understand the reported MSA behaviors;to demonstrate further applications of MSA,we introduce some methods to improve the ordered degree of the assembled structures from the point of precise assembly and thus envision some possible fields for the use of MSA.

关键词： Macroscopic supramolecular assembly Multivalency Supramolecular materials 3D ordered structures Precise assembly

Recent Advances in Fibrous Materials for Hydroelectricity Generation

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nano-Micro Letters 2025年第2期17卷 109-133页

作者： Can Ge Duo Xu Xiao feng Xing y.ng Zheheng Song yuhang Song Jingyu Chen y.ngcun Liu Chong Gao y.ng Du Zhe Sun Weilin Xu Jian Fang College of Textile and Clothing Engineering Soochow UniversitySuzhou 215123People’s Republic of China national Engineering Laboratory for Modern Silk Soochow UniversitySuzhou 215123People’s Republic of China State Key Laboratory of new Textile Materials and Advanced Processing Technologies Wuhan Textile UniversityWuhan 430200People’s Republic of China Institute of Functional nano&Soft Materials(FUnSOM) Soochow UniversitySuzhou 215123People’s Republic of China Department of Electrical and Computer Engineering University of MassachusettsAmherstMA 01003USA Department of Materials Imperial College LondonSouth Kensington CampusLondon SW72AZUK College of Textile Science and Engineering Zhejiang Sci-Tech UniversityHangzhou 310018People’s Republic of China School of Materials Science and Engineering Shanghai Institute of Technology100 Haiquan RoadShanghai 201418People’s Republic of China

Depleting fossil energy sources and conventional polluting power generation pose a threat to sustainable *** generation from ubiquitous and spontaneous phase transitions between liquid and gaseous water has been considered a promising strategy for mitigating the energy *** materials with unique flexibility,processability,multifunctionality,and practicability have been widely applied for fibrous materials-based hydroelectricity generation(FHG).In this review,the power generation mechanisms,design principles,and electricity enhancement factors of FHG are first ***,the fabrication strategies and characteristics of varied constructions including 1D fiber,1D yarn,2D fabric,2D membrane,3D fibrous framework,and 3D fibrous gel are ***,the advanced functions of FHG during water harvesting,proton dissociation,ion separation,and charge accumulation processes are analyzed in ***,the potential applications including power supply,energy storage,electrical sensor,and information expression are also ***,some existing challenges are considered and prospects for future development are sincerely proposed.

关键词： Hydroelectricity Fibrous material Streaming potential Ion diffusion

neurocircuit regeneration by extracellular matrix reprogramming

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neural Regeneration Research 2025年第8期20卷 2300-2301页

作者： Shengzhang Su Ian n.Levasseur Kimberly M.Alonge Department of Medicinal Chemistry University of WashingtonSeattleWAUSA Department of Chemistry University of WashingtonSeattleWAUSA Department of Medicine University of Washington Medicine Diabetes InstituteSeattleWAUSA

The brain's extracellular matrix(ECM),which is comprised of protein and glycosaminoglycan(GAG)scaffolds,constitutes 20%-40% of the human brain and is considered one of the largest influencers on brain cell functioning(Soles et al.,2023).Synthesized by.neural and glial cells,the brain's ECM regulates a myriad of homeostatic cellular processes,including neuronal plasticity and firing(Miyata et al.,2012),cation buffering(Moraws ki et al.,2015),and glia-neuron interactions(Anderson et al.,2016).Considering the diversity of functions,dynamic remodeling of the brain's ECM indicates that this understudied medium is an active participant in both normal physiology and neurological diseases.

关键词： matrix programming

An Efficient Boron Source Activation Strategy for the Low‑Temperature Synthesis of Boron nitride nanotubes

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nano-Micro Letters 2025年第1期17卷 548-558页

作者： y.ng Wang Kai Zhang Liping Ding Liy.n Wu Songfeng E Qian He nany.ng Wang Hui Zuo Zhengy.ng Zhou feng Ding yue Hu Jin Zhang yagang yao national Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional Materialsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093People’s Republic of China School of Electronic Information and Artificial Intelligence Shaanxi University of Science&TechnologyXian 710000People’s Republic of China College of Bioresources Chemical and Materials Engineering Shaanxi University of Science&TechnologyXian 710000People’s Republic of China Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325000People’s Republic of China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518000People’s Republic of China College of Chemical and Molecular Engineering Peking UniversityBeijing 100871People’s Republic of China

Lowering the synthesis temperature of boron nitride nanotubes(BnnTs)is crucial for their *** primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid *** this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B *** approach can be adopted to form various low-melting-point AM–Mg–B–O growth *** growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BnnTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with n atoms to form Bn *** findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BnnTs.

关键词： Boron nitride nanotubes Low-temperature Boron activation Density functional theory