Discovery of Extraplanar H i Clouds and a H i Tail in the M101 Galaxy Group with FAST

We present a new high-sensitivity H i observation toward nearby spiral galaxy M101 and its adjacent 2° × 2° region using the Five-hundred-meter Aperture Spherical radio Telescope (FAST). From the observation, we detect a more extended and asymmetric H i disk around M101. While the H i velocity field within the M101's optical disk region is regular, indicating that the relatively strong disturbance occurs in its outer disk. Moreover, we identify three new H i clouds located on the southern edge of the M101's H i disk. The masses of the three H i clouds are 1.3 × 107 M ⊙, 2.4 × 107 M ⊙, and 2.0 × 107 M ⊙, respectively. The H i clouds similar to dwarf companion NGC 5477 rotate with the H i disk of M101. Unlike NGC 5477, they have no optical counterparts. Furthermore, we detect a new H i tail in the extended H i disk of M101. The H i tail detected gives reliable evidence for M101 interaction with the dwarf companion NGC 5474. We argue that the extraplanar gas (three H i clouds) and the H i tail detected in the M101's disk may originate from a minor interaction with NGC 5474.

First Clinical Results of Modular Intraocular Lens Implantation

Introduction. Recent population studies reveal steady growth in intraocular lens (IOL) exchanges including those for refractive and other optical reasons. To lower complication risks related to IOL exchange, we introduced a modular IOL model with replaceable optical part.Purpose: preliminary analysis of modular IOL implantation clinical results.Patients and methods. From August 2018 to February 2020, five patients as part of their surgical treatment for various forms of cataract received newly designed modular IOLs. The modular IOL is composed of two separate parts — haptic and optic, manufactured from the same elastic acrylic material with hydrophobic properties. The haptic includes a closed ring and a pair of open equally distant loops in a unified design. The haptic ring with projections serves as a base for optical disk. The current study evaluated characteristics of the IOL implantation and assembly process, as well as possible development of intra- and early postoperative complications.Results. First implantations of the modular IOL accomplished using standard surgical instrumentation and disposables passed without complications. We did not observe scratches, breaks or any other mechanical damage to neither haptic, nor optical parts. During simultaneous implantation, optical disks fixated in haptic rings preserved their due positioning after transiting through slender injector channel. There were no specific, modular-IOL related complications in the early postoperative period. The optical disk maintained correct location, delimited by fixation leaflets of the haptic ring.Conclusion. Early results for clinical application of the novel modular IOL demonstrated feasibility of its safe implantation in disassembled and preassembled modes.

Semantic Segmentation of Eye Fundus Images Using Convolutional Neural Networks

The article reviews the problems of eye bottom fundus analysis and semantic segmentation algorithms used to distinguish eye vessels, optical disk. Various diseases, such as glaucoma, hypertension, diabetic retinopathy, macular degeneration, etc., can be diagnosed by changes and anomalies of vesssels and optical disk. For semantic segmentation convolutional neural networks, especially U-Net architecture, are well suited. Recently a number of U-Net modifications have been developed that deliver excellent performance results.

Semantic Segmentation of Eye Fundus Images Using Convolutional Neural Networks

This article reviews the problems of eye bottom fundus analysis and semantic segmentation algorithms used to distinguish the eye vessels and the optical disk. Various diseases, such as glaucoma, hypertension, diabetic retinopathy, macular degeneration, etc., can be diagnosed through changes and anomalies of the vesssels and optical disk. Convolutional neural networks, especially the U-Net architecture, are well-suited for semantic segmentation. A number of U-Net modifications have been recently developed that deliver excellent performance results.