Results 41 to 50 of about 61,280 (177)

Prevalence and risk factors for astigmatism in 7 to 19-year-old students in Xinjiang, China: a cross-sectional study

BMC Ophthalmology
Background To investigate the prevalence and risk factors for astigmatism in 7-19-year-old students in Xinjiang, China. Methods A school-based, cross-sectional study was conducted on students who underwent refraction examination in Xinjiang, China ...
Yan Wang, Jingyu Mu, Yining Yang, Xiaolong Li, Han Qin, Batima Mulati, Zhen Wang, Wei Gong, Yong Zhao, Yunxian Gao   +9 more
doaj   +1 more source

Anterior and Posterior Corneal Astigmatism after Refractive Lenticule Extraction for Myopic Astigmatism

Journal of Ophthalmology, 2015
Purpose. To assess the amount and the axis orientation of anterior and posterior corneal astigmatism after refractive lenticule extraction (ReLEx) for myopic astigmatism. Methods. We retrospectively examined 53 eyes of 53 consecutive patients (mean age ±
Kazutaka Kamiya, Kimiya Shimizu, Mayumi Yamagishi, Akihito Igarashi, Hidenaga Kobashi   +4 more
doaj   +1 more source

Ritchey-Chretien Telescope [PDF]

, 1973
A Ritchey-Chretien telescope is described which was designed to respond to images located off the optical axis by using two transparent flat plates positioned in the ray path of the image.
Amon, M., Rosin, S.
core   +1 more source

Evaluating the predictive relationship between manifest refractive astigmatism, topographic astigmatism, and ocular residual astigmatism: A comparative study

Journal of International Medical Research
Background The interaction between manifest refractive astigmatism and topographic astigmatism is critical in planning refractive surgery. This study aimed to investigate the predictive relationship between manifest refractive astigmatism and topographic
Wissam Yosif, Ahmed Shakir Al-Wassiti, Ali Nema Abushnein, Muthanna Basheer Yasir   +3 more
doaj   +1 more source

Numerical correction of anti-symmetric aberrations in single HRTEM images of weakly scattering 2D-objects [PDF]

, 2014
Here, we present a numerical post-processing method for removing the effect of anti-symmetric residual aberrations in high-resolution transmission electron microscopy (HRTEM) images of weakly scattering 2D-objects.
Chen, Ming-Wei, Geiger, Dorin, Kaiser, Ute, Kis, Andras, Lee, Zhongbo, Lehtinen, Ossi, Whitwick, Michale B.   +6 more
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Contributions of Anterior Corneal and Ocular Residual Astigmatism to Autorefraction Astigmatism in a Myopic Adult Sample

Clinical Ophthalmology, 2020
Amr A Gab-Alla Ophthalmology Department, Faculty of Medicine, Suez Canal University, Ismailia, EgyptCorrespondence: Amr A Gab-AllaOphthalmology Department, Faculty of Medicine, Suez Canal University, Ring Road, Ismailia, EgyptTel +20 1222836261Email ...
Gab-Alla AA
doaj  

The Impact of Posterior Corneal Astigmatism on Surgically Induced Astigmatism in Cataract Surgery

International Journal of General Medicine, 2022
Wenjie Liu,* Lichun Yang,* Jiewei Liu Cataract Department, Shanxi Eye Hospital, Taiyuan, Shanxi Province, People’s Republic of China*These authors contributed equally to this workCorrespondence: Jiewei Liu, Email jieweiliu1967@163.comPurpose:
Liu W, Yang L, Liu J
doaj  

Correlation Between Stereoacuity and Experimentally Induced Graded Monocular and Binocular Astigmatism [PDF]

Journal of Clinical and Diagnostic Research, 2016
Introduction: Stereopsis, the highest grade of binocular single vision, is affected by various factors, such as mis-alignment of visual axes, refractive errors especially anisometropia and astigmatism, both of which may result in amblyopia. There are
Varsha Kulkarni, Neelam Puthran, Bhavna Gagal   +2 more
doaj   +1 more source

Age- and gender-related characteristics of astigmatism in a myopic population

Frontiers in Medicine, 2022
PurposeTo explore age- and gender-related differences of refractive and corneal astigmatism in myopic patients looking for refractive surgery.DesignA retrospective cross-sectional study.Materials and methodsThe medical files of candidates looking for ...
Shan Yang, Yang Jiang, Ge Cui, Ying Li
doaj   +1 more source

Primary Beam and Dish Surface Characterization at the Allen Telescope Array by Radio Holography

, 2011
The Allen Telescope Array (ATA) is a cm-wave interferometer in California, comprising 42 antenna elements with 6-m diameter dishes. We characterize the antenna optical accuracy using two-antenna interferometry and radio holography. The distortion of each
Ackermann, R. F., ATA GROUP, Atkinson, Shannon, Backer, D. C., Backus, P. R., Barott, William, Bauermeister, Amber, Blair, Samantha K., Blitz, Leo, Bock, D. C. -J., Bower, Geoffrey C., Bradford, Tucker, Cheng, Calvin, Croft, Steve, Davis, M. M., DeBoer, D. R., Dexter, Matt, Dreher, John, Engargiola, Greg, Fields, Ed, Forster, J. R., Gutierrez-Kraybill, Colby, Harp, G. R., Heiles, Carl, Helfer, Tamara, Jordan, Jane, Jorgensen, Susan, Keating, Garrett, Kilsdonk, Tom, Law, Casey, Lugten, John, MacMahon, D. H. E., McMahon, Peter, Milgrome, Oren, Nadler, Z. J., Pierson, Tom, Randall, Karen, Ross, John, Shostak, Seth, Siemion, Andrew, Smolek, Ken, Tarter, J. C., Thornton, Douglas, Urry, Lynn, Welch, W. J., Werthimer, Dan, Whysong, David, Williams, Peter K. G., Wright, M. C. H.   +48 more
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