A method for numerical estimation and correction of aberrations of the eye in fundus imaging with optical coherence tomography (OCT) is presented. Aberrations are determined statistically by using the estimate based on likelihood function maximization. The method can be considered as an extension of the phase gradient autofocusing algorithm in synthetic aperture radar imaging to 2D optical aberration correction. The efficacy of the proposed method has been demonstrated in OCT fundus imaging with 6λ aberrations. After correction, single photoreceptors were resolved. It is also shown that wave front distortions with high spatial frequencies can be determined and corrected.
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http://dx.doi.org/10.1002/jbio.202000112 | DOI Listing |
Alzheimers Dement
December 2024
Drexel University college of medicine, Philadelphia, PA, USA.
Background: In tauopathies, such as Frontotemporal Dementia (FTD), tau loses association with microtubules (MTs) and forms neurofibrillary tangles. Tau is an abundant MT-associated protein in neurons, which essentially regulate MT properties. Because pathological tau binds less avidly to MTs, which was thought to reduce the levels and stability of axonal MTs.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Ophthalmology, Kanazawa Medical University, Kahoku, Ishikawa, Japan.
Photic phenomena are more pronounced in presbyopia-corrected than in monofocal intraocular lens (IOL), causing dissatisfaction after cataract surgery. Photic Phenomena Test (PPT) quantifies photic phenomena in eyes with two types of presbyopia-corrected IOL. We examined the relationship between preoperative eye shape and pupil diameter.
View Article and Find Full Text PDFAdv Mater
January 2025
School of Materials Science and Engineering, South China University of Technology, Guangzhou, 510641, China.
Understanding the behavior of high-entropy carbides (HECs) under oxygen-containing environments is of particular importance for their promising applications in structural components, catalysis, and energy-related fields. Herein, the structural evolution of (Ta, Ti, Cr, Nb)C (HEC-1) nanoparticles (NPs) is tracked in situ during the oxidation at the atomic scale by using an open-cell environmental aberration-corrected scanning transmission electron microscope. Three key stages are clearly discerned during the oxidation of HEC-1 NPs at the atomic level below 900 °C: i) increased amorphization of HEC-1 NPs from 300 to 500 °C due to the energetically favorable formation of carbon vacancies and substitution of carbon with oxygen atoms; ii) nucleation and subsequent growth of locally ordered nanocluster intermediates within the generated amorphous oxides from 500 to 800 °C; and iii) final one-step crystallization of non-equimolar MeO and MeO (Me = metallic elements, Ta, Ti, Cr, and Nb) high-entropy oxides above 800 °C, accompanied with the reduction in atomic defects.
View Article and Find Full Text PDFLight Sci Appl
January 2025
Department of Physics, University of Washington, Seattle, WA, USA.
Wide field of view and light weight optics are critical for advanced eyewear, with applications in augmented/virtual reality and night vision. Conventional refractive lenses are often stacked to correct aberrations at a wide field of view, leading to limited performance and increased size and weight. In particular, simultaneously achieving a wide field of view and large aperture for light collection is desirable but challenging to realize in a compact form-factor.
View Article and Find Full Text PDFJ Affect Disord
December 2024
Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, People's Republic of China; Tianjin Key Laboratory of Brain Science and Neural Engineering, Tianjin University, Tianjin, People's Republic of China; Haihe Laboratory of Brain-Computer Interaction and Human-Machine Integration, Tianjin, People's Republic of China. Electronic address:
Generalized anxiety disorder (GAD) is a common anxiety disorder characterized by excessive, uncontrollable worry and physical symptoms such as difficulty concentrating and sleep disturbances. Although functional magnetic resonance imaging (fMRI) studies have reported aberrant network-level activity related to cognition and emotion in GAD, its low temporal resolution restricts its ability to capture the rapid neural activity in mental processes. EEG microstate analysis offers millisecond-resolution for tracking the dynamic changes in brain electrical activity, thereby illuminating the neurophysiological mechanisms underlying the cognitive and emotional dysfunctions in GAD.
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