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The fractional Fourier transform (FRT) is applied to partially coherent twisted anisotropic Gaussian-Schell model (GSM) beams based directly on the cross-spectral density. An analytical and concise formula is derived for the cross-spectral density of partially coherent twisted anisotropic GSM beams passing through a FRT system in terms of the tensor method. The corresponding tensor ABCD law for performing a FRT is obtained. The connection between the FRT formula and the generalized Collins formula for partially coherent beams is discussed. The formulas derived provide a powerful tool for analyzing and calculating the FRTs of partially coherent beams.
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http://dx.doi.org/10.1364/ol.27.001672 | DOI Listing |
Neuroscience
September 2025
Department of Human Movement Sciences, Faculty of Behavioral and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, the Netherlands. Electronic address:
Walking without falling requires correcting the deviations of the centre of mass (CoM) trajectory relative to the base of support. This process is partially under feedback control. We investigated whether vestibular afference contributes to estimating CoM state to stabilize walking.
View Article and Find Full Text PDFACS Photonics
August 2025
Nanophotonic Systems Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, Tannenstrasse 3, Zurich 8092, Switzerland.
Interferometric-based microscopies stand as powerful label-free approaches for monitoring and characterizing chemical reactions and heterogeneous nanoparticle systems in real time with single-particle sensitivity. Nevertheless, coherent artifacts, such as speckle and parasitic interferences, together with limited photon fluxes from spatially incoherent sources, pose an ongoing challenge in achieving both high sensitivity and throughput. In this study, we systematically characterize how partial coherence affects the signal contrast and background noise level in inline holography microscopes operated in a reflection geometry, a category that encompasses interferometric scattering microscopy (iSCAT).
View Article and Find Full Text PDFSci Rep
August 2025
Department of Neurology, Medical Faculty, University Hospital Düsseldorf, Heinrich-Heine-University, Düsseldorf, Germany.
Multiple Sclerosis (MS), an autoimmune disorder, is characterized by severe neuroinflammation, leading to demyelination and neuronal damage in the CNS, resulting in significant clinical impairment. MS progression involves complex pathological processes like immune cell invasion and cytokine-mediated recruitment to the CNS. Experimental autoimmune encephalomyelitis (EAE), widely used as a model for MS, despite its translational limitations, has been crucial for identifying effective treatments.
View Article and Find Full Text PDFJ Neuroophthalmol
August 2025
College of Medicine (SS), University of Florida, Gainesville, Florida; Escuela de Medicina. Fundación Universitaria Sanitas, Bogotá (LR-S, JVR-L), Colombia; Vision Colombia Research Group (JVR-L), Fundación Universitaria Sanitas, Bogota, Colombia; and Department of Ophthalmology (AJM-V), College
Background: There is a global shortage of neuro-ophthalmologists, driven by an aging workforce and declining interest among residents. Emerging data indicate that this supply-demand mismatch results in prolonged patient wait times, leading to evaluation by additional physicians, delayed/incorrect diagnosis, and postponed therapy. However, data on referral patterns are primarily from resource-rich countries.
View Article and Find Full Text PDFSci Rep
August 2025
Department of Physics, Sree Chaitanya College, Habra (WB State University), North 24 Parganas, 743268, W. B., India.
It is newly proposed that the presence of the near dipole-dipole (NDD) interaction effect in an optically dense atomic ensemble may be very useful for controlling high-precision atom localization. In the present work based on observing the NDD effect-induced space-dependent-absorption of a weak probe field operating in a partially closed four-level Y-type atomic system, we have shown the NDD parameter being an efficient control knob along with the other system parameters for easier optimization of the localization pattern with enhanced detection probability in three-dimensional (3D) space. Controlling localization patterns at lower and larger values of NDD parameter is discussed at different physical conditions.
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