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Femtosecond laser-assisted astigmatic keratotomy: a review

Eye and Vision 2018年第1期5卷 59-69页

作者： john s.m.chang Department of Ophthalmology Hong Kong Sanatorium&Hospital8/FLi Shu Pui BlockPhase II2 Village RoadHappy ValleyHong KongChina

Background:Astigmatic keratotomy(AK)remains an accessible means to correct surgically induced or naturally occurring *** advantages of femtosecond laser-assisted astigmatic keratotomy(FsAK)over conventional methods have been recognized *** text:This review evaluates the efficacy,complications,and different methods of FsAK for correction of astigmatism in native eyes and those that underwent previous penetrating keratoplasty(PKP).The penetrating and intrastromal FsAK(IFsAK)techniques can reduce post-keratoplasty astigmatism by 35.4%to 84.77%and 23.53%to 89.42%,*** native eyes,the penetrating and IFsAK techniques reduce astigmatism by 26.8%to 58.62%and 36.3%to 58%respectively,implying that the magnitude of the astigmatic reduction is comparable between the two FsAK ***,IFsAK offers the additional advantages of almost no risk of infection,wound gape,and epithelial *** use of nomograms,anterior-segment optical coherence tomography,and consideration of posterior cornea and corneal biomechanics are helpful to enhance the efficacy and safety of *** complications of FsAK in eyes that underwent PKP include overcorrection,visual loss,microperforations,infectious keratitis,allograft rejection,and *** reported difficulties in native eyes include overcorrection,anterior gas breakthrough,and suction ***:In eyes that underwent PKP,FsAK effectively reduces high regular or irregular astigmatism,with rare and manageable ***,the drawbacks of the procedure include the potential loss of visual acuity and low *** native eyes undergoing femtosecond laser-assisted cataract surgery,IFsAK is a good choice to correct low astigmatism(s).The refractive effect of astigmatism from the posterior cornea needs to be considered in the nomograms for native eyes undergoing refractive cataract *** further improve the efficacy of FsAK,more large-scale ra

关键词： Femtosecond laser-assisted astigmatic keratotomy Post-keratoplasty astigmatism Astigmatism correction Refractive surgery

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Polaron Effect of a Two Electron Parabolic Quantum Dot

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Communications in Theoretical Physics 2013年第6期59卷 763-768页

作者： s.saravana Kumar A.john Peter chang Kyoo Yoo Department of Physics Nadar Saraswathi College of Engineering and Tecchnology Vadapudupatti Department of Physics Government Arts College Center for Environmental studies/Green Energy Center Department of Environmental Science and Engineering Collegeof Engineering Kyung Hee University

Polaron induced double electron in a quantum dot is investigated using the exact diagonalization techniques and the compact density-matrix approach. The dependence of nonlinear optical processes on the incident photon energies and the polaronic effect are brought out. The linear, third order non-linear optical absorption coefficients and the refractive index changes of singlet and triplet states as a function of photon energy are obtained with and without the inclusion of polaronic effect. It is found that the geometrical confinement and the effect of polaron have great influence on the optical properties of dots.

关键词： parabolic quantum dot correlation energy semiconductor

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Electronic and optical properties of Cds/CdZns nanocrystals

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Chinese Physics B 2012年第8期21卷 441-448页

作者： A.john Peter chang Woo Lee epartment of Chemical Engineering and Green Energy Center College of EngineeringKyung Hee University1 SeochunGihungYonginGyeonggi 446-701S.Korea Department of Physics Govt.Arts CollegeMelurMadurai-62510India Department of Chemical Engineering and Green Energy Center College of EngineeringKyung Hee University1 SeochunGihungYonginGyeonggi 446-701S.Korea

Cd1-xZnxs nanocrystals are prepared by a co-precipitation method with different atomic fractions of Zn. The texture, structural transformation and optical properties with increasing x value in Cd1-xZnxs are studied with scanning electron microscopy, electron diffraction patterning, and absorption spectra respectively. Quantum confinement in a strained Cds/Cd1-xZnxs related nanodot with various Zn content values is investigated theoretically. Binding energies on exciton bound Cds/CdxZn1-xs quantum dot are computed, with consideration of the internal electric field induced by the spontaneous and piezoelectric polarizations, and thereby the interband emission energy is calculated as a function of the dot radius. The optical band gap from the UV absorption spectrum is compared with the interband emission energy computed theoretically. Our results show that the average diameter of composite nanoparticles ranges from 3 nm to 6 nm. The X-ray diffraction pattern shows that all the peaks shift towards the higher diffracting angles with an increase in Zn content. The lattice constant gradually decreases as the Zn content increases. The strong absorption edge shifts towards the lower wavelength region and hence the band gap of the films increases as the Zn content increases. The values of the absorption edge are found to shift towards the shorter wave length region and hence the direct band gap energy varies from 2.5 eV for the Cds film and 3.5 eV for the Zns film. Our numerical results are in good agreement with the experimental results.

关键词： quantum dots quasicrystals semiconductor

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Interaction between gut microbiota and COVID-19 and its vaccines

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World Journal of Gastroenterology 2022年第40期28卷 5801-5806页

作者： john s m Leung Cardiothoracic Unit St.Paul’s HospitalHong KongChina

The whole world has been continuously afflicted by the coronavirus disease 2019(COVID-19)pandemic for the past 3 *** countries have tried many methods to control this virus infection with varying successes and *** gut microbiota is a biosystem spanning the entire length of the digestive tract and playing important roles in health and *** is much affected by *** return it also substantially impacts *** particular,the gut microbiota has established a bidirectional interaction with the COVID-19 vaccines,enhancing or reducing vaccine efficacy by virtue of its varying ***,COVID-19 vaccines also make a substantial impact on the gut microbiota,reducing its overall population and *** is hoped that by exploring and harnessing this bidirectional interaction we may break new ground and develop new methods to prevent and treat this formidable virus infection.

关键词： Gut microbiota COVID-19 vaccines Vaccine interactions Gut microbiota alterations

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Photo-Induced Electron spin Polarization in a Narrow Band Gap semiconductor Nanostructure

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Chinese Physics Letters 2012年第11期29卷 186-190页

作者： A.john Peter chang Woo Lee Department of Chemical Engineering and Green Energy Center College of EngineeringKyung Hee University1 SeochunGihungYonginGyeonggi 446-701S.Korea

Photo-induced spin dependent electron transmission through a narrow gap Insb/InGa_(x)sb_(1-x) semiconductor symmetric well is theoretically studied using transfer matrix *** transparency of electron transmission is calculated as a function of electron energy for different concentrations of *** spin-polarized photon assisted resonant tunnelling in the heterostructure due to Dresselhaus and Rashba spin-orbit coupling induced splitting of the resonant level and compressed spin-polarization are *** results show that Dresselhaus spin-orbit coupling is dominant for the photon effect and the computed polarization efficiency increases with the photon effect and the gallium concentration.

关键词： polarization resonant photon

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Limited infection by ‘Candidatus Liberibacter asiaticus’ in ‘Valencia’ sweet orange trees in the presence of Citrus tristeza virus

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Journal of Integrative Agriculture 2019年第10期18卷 2284-2293页

作者： FU shi-min Cristina Gouin ZHOU chang-yong john s. Hartung National Citrus Engineering Research Center Citrus Research InstituteChinese Academy of Agricultural Sciences/Southwest UniversityChongqing 400712P.R.China molecular Plant Pathology Laboratory United States Department of Agriculture-Agricultural Research ServiceBeltsvilleMaryland 20705USA Biotechnology and Regulatory services United States Department of Agriculture-Animal and Plant Health Inspection ServiceRiverdaleMaryland 20705USA

Huanglongbing (HLB) is the most destructive disease of citrus and is associated with ‘Candidatus Liberibacter asiaticus’(CLas), a member of the α-proteobacteria. Citrus tristeza virus (CTV) is another pathogen of citrus with very great historic as well as current importance. Both CLas and CTV are phloem-restricted pathogens. A severe CTV isolate, CTV-B6, and CLas-B232 induce a group of symptoms of phloem dysfunction that overlap, but the mild isolate CTV-B2 does not cause any loss to commercial trees. Prior inoculation and establishment of CLas-B232 did not affect subsequent establishment of either CTV-B2 or CTV-B6, while super infection by CLas-B232 was reduced by prior establishment of CTV-B2 and to a lesser extent by prior infection with CTV-B6. Trees co-infected with CTV-B6 and CLas-B232 developed more severe symptoms, typical of CTV-B6, than either of the two pathogens co-infected with CTV-B2. In this study, we confirmed that CLas established in the rootlets earlier and with higher concentration than in leaves. The distribution of CLas in the plant infected by CLas-B438 alone and with CTV-B2 fits a previously proposed model but CLas was more sporadically distributed in a plant co-infected by CLas and CTV-B2 than in a plant infected by CLas alone. These biological phenomena are aligned with previously analyzed transcriptome data and the study provides a novel idea that mild CTV strains may provide some protection against CLas by limiting its multiplication and spread. The protective effect may be due to opposite regulation of key host defense pathways in response to CTV-B2 and CLas-B438.

关键词： huanglongbing plant defense plant protection

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Direct Photolithography of WO<sub>xsub> Nanoparticles for High-Resolution Non-Emissive Displays

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NANO-mICRO LETTERs 2025年第1期17卷 1-13页

作者： Gu, chang Yang, Guojian Wang, Wenxuan shi, Aiyan Fang, Wenjuan Qian, Lei Hu, Xiaofei Zhang, Ting Xiang, Chaoyu Zhang, Yu-mo Chinese Acad sci Ningbo Inst Mat Technol & Engn Lab Optoelect Informat Technol & Devices Ningbo 315201 Peoples R China Qianwan Inst CNITECH Hangzhou Bay Lab Adv Nanooptoelectron Mat & Device Ningbo 315336 Peoples R China Zhejiang Univ Innovat Ctr Yangtze River Delta Smart Mat Architecture Res Lab Jiaxing 314100 Peoples R China Univ sci & Technol China Hefei 230026 Peoples R China Jilin Univ Coll Chem State Key Lab Supramol Struct & Mat Changchun 130012 Peoples R China

High-resolution non-emissive displays based on electrochromic tungsten oxides (WOx) are crucial for future near-eye virtual/augmented reality interactions, given their impressive attributes such as high environmental stability, ideal outdoor readability, and low energy consumption. However, the limited intrinsic structure of inorganic materials has presented a significant challenge in achieving precise patterning/pixelation at the micron scale. Here, we successfully developed the direct photolithography for WOx nanoparticles based on in situ photo-induced ligand exchange. This strategy enabled us to achieve ultra-high resolution efficiently (line width mu>m, the best resolution for reported inorganic electrochromic materials). Additionally, the resulting device exhibited impressive electrochromic performance, such as fast response (s at 0 V), high coloration efficiency (119.5 cm(2) C-1), good optical modulation (55.9%), and durability (> 3600 cycles), as well as promising applications in electronic logos, pixelated displays, flexible electronics, etc. The success and advancements presented here are expected to inspire and accelerate research and development (R&D) in high-resolution non-emissive displays and other ultra-fine micro-electronics.

关键词： Electrochromic Direct photolithography WOx nanoparticles In situ photo-induced ligand exchange High-resolution displays

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Contemporary approaches to visual prostheses

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military medical Research 2019年第3期6卷 254-262页

作者： Rebecca m.mirochnik john s.Pezaris Department of Bioengineering Northeastern UniversityBostonMAUSA Department of Neurosurgery Massachusetts General HospitalBostonMAUSA.3Department of NeurosurgeryHarvard MedicalSchoolBostonMAUSA.

Visual prostheses serve to restore visual function following acquired blindness. Acquired blindness(as opposed to congenital blindness) has many causes, including diseases such as retinitis pigmentosa, glaucoma, and macular degeneration, or trauma such as caused by automobile accident or blast damage from explosions. many of the blindness-causing diseases target the retina or other ocular structure. Often, despite the loss of sensitivity to light, the remainder of the visual pathway is still functional, enabling electrical devices to deliver effective and meaningful visual information to the brain via arrays of electrodes. These arrays can be placed in any part of the early visual pathway, such as the retina, optic nerve, lateral geniculate nucleus, or visual cortex. A camera or other imaging source is used to drive electrical stimulation of remaining healthy cells or structures to create artificial vision and provide restoration of function. In this review, each approach to visual prostheses is described, including advantages and disadvantages as well as assessments of the current state of the art. most of the work to-date has been targeting stimulation of(a) the retina, with three devices approved for general use and two more in clinical testing;(b) the lateral geniculate nucleus, with efforts still in the pre-clinical stage;and(c) the cortex, with three devices in clinical testing and none currently approved for general use despite the longest history of investigation of the three major approaches. Each class of device has different medical indications, and different levels of invasiveness required for implantation. All contemporary devices deliver relatively poor vision. There has been remarkable progress since the first proof-ofconcept demonstration that used stimulation of the primary visual cortex, with the field exploring all viable options for restoration of function. much of the progress has been recent, driven by advances in microelectronics and biocompat

关键词： Visual prosthesis Blindness Artificial vision

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some insights into how barnacles survive as sessile organisms

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Integrative Zoology 2009年第4期4卷 395-401页

作者： john s.BUCKERIDGE Jessica m.REEVEs Earth and Oceanic systems Research Group RMIT UniversityMelbourneAustralia

During routine chemical analyses of the stalked ibliform barnacle Chaetolepas calcitergum Buckeridge&Newman 2006,peaks of more than 7%(by dry mass)of bromine were *** bromine ions occur in seawater(up to 66 ppm),this level of accumulation,in the soft tissue of the barnacle,is *** concentration of bromine compounds occurs in a number of invertebrates,such as algae and sponges,but this is the first record of elevated bromine in goose *** high accumulation of bromine compound(s)is most likely a defense *** present paper includes a review of the mechanisms deployed by barnacles to repel predators.

关键词： bromine Chaetolepas calcitergum Cirripedia defense mechanisms Ibliformes.

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Newly Discovered scheelite in Quartz Vein-type Gold Deposits, Xiaoqinling Gold District, and its Geological significance

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Acta Geologica sinica(English Edition) 2020年第4期94卷 1305-1307页

作者： chang ming LIU Jiajun CARRANZA Emmanuel john m YIN Chao ZHAI Degao WU Tong state Key Laboratory of Geological Processes and mineral Resources China University of GeosciencesBeijing 100083China school of Earth sciences and Resources China University of GeosciencesBeijing 100083China Geological sciences School of AgriculturalEarth and Environmental SciencesUniversity of KwaZulu-NatalDurban 4000Republic of South Africa

Objective The Xiaoqinling district is the second largest goldbearing province in China after the Jiaodong region located in the eastern North China Craton. At present, seven large, 20 medium-sized and 28 small gold deposits have been discovered, and more than 1200 gold-bearing quartz veins have been identified within the metamorphic rocks of the Taihua Group. The total gold reserves are over 800 tons.

关键词： Quartz sized quartz

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