To evaluate tissue changes, we studied myocardial texture using two-dimensional echocardiographic images. We investigated 19 normal subjects, 28 patients with left ventricular hypertrophy, and 12 patients with old anteroseptal myocardial infarction of longer than one year duration. Using 2.5, 3.5, and 5.0 MHz transducers, two-dimensional echocardiograms in the parasternal long-axis view were obtained, and the textures of the interventricular septal images were classified in three types; type I, with a nearly uniformly speckled or echolucent appearances; type II, with multiple, discrete, small (2 to 4 mm) highly refractile echoes; type III, with larger highly refractile echoes (greater than 4 mm) appearing as a cluster of broad patches or band-like echoes. Normal subjects belonged to the type I texture, while many with left ventricular hypertrophy belonged to the type II category. Type III was often observed in patients with old anteroseptal infarction. Using a transducer of higher frequency, there tended to be a shift from type II to I or type III to II. In phantom experiments using carbolandam granules instead of the myocardium, the echocardiographic texture became rough when the phantom was farther from the transducer or the transducer was of low frequency. We suggest that the texture in two-dimensional images may reflect myocardial tissue changes, when other factors including the apparatus and technique remain stable.
Download full-text PDF |
Source |
---|
Nano Lett
January 2025
Department of Physics, Arizona State University, Tempe, Arizona 85287, United States.
Experimental detection of antiferromagnetic order in two-dimensional materials is a challenging task. Identifying multidomain antiferromagnetic textures via the current techniques is even more difficult. Therefore, we investigate the higher-order multipole moments in twisted bilayer MnPSe.
View Article and Find Full Text PDFACS Nano
January 2025
School of Materials Science and Engineering, Peking University, Beijing 100871, People's Republic of China.
Single-crystal Au(111), renowned for its chemically inert surface, long-range "herringbone" reconstruction, and high electrical conductivity, has long served as an exemplary template in diverse fields, , crystal epitaxy, electronics, and electrocatalysis. However, commercial Au(111) products are high-priced and limited to centimeter sizes, largely restricting their broad applications. Herein, a low-cost, high-reproducible method is developed to produce 4 in.
View Article and Find Full Text PDFEntropy (Basel)
January 2025
LARIS, SFR MATHSTIC, Univ Angers, F-49000 Angers, France.
Entropy algorithms are widely applied in signal analysis to quantify the irregularity of data. In the realm of two-dimensional data, their two-dimensional forms play a crucial role in analyzing images. Previous works have demonstrated the effectiveness of one-dimensional increment entropy in detecting abrupt changes in signals.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Computer Science and Technology, Qilu University of Technology, No. 3501 Daxue Road, Jinan, 250300, Shandong, China.
Feature matching in computer vision is crucial but challenging in weakly textured scenes due to the lack of pattern repetition. We introduce the SwinMatcher feature matching method, aimed at addressing the issues of low matching quantity and poor matching precision in weakly textured scenes. Given the inherently significant local characteristics of image features, we employ a local self-attention mechanism to learn from weakly textured areas, maximally preserving the features of weak textures.
View Article and Find Full Text PDFSci Rep
January 2025
Helmholtz-Zentrum Berlin für Materialien und Energie, 13109, Berlin, Germany.
Incommensurate magnetic phases in chiral cubic crystals are an established source of topological spin textures such as skyrmion and hedgehog lattices, with potential applications in spintronics and information storage. We report a comprehensive small-angle neutron scattering (SANS) study on the B20-type chiral magnet Cr[Formula: see text]Mn[Formula: see text]Ge, exploring its magnetic phase diagram and confirming the stabilization of a skyrmion lattice under low magnetic fields. Our results reveal a helical ground state with a decreasing pitch from 40 to 35 nm upon cooling, and a skyrmion phase stable in applied magnetic fields of 10-30 mT, and over an unusually wide temperature range for chiral magnets of 6 K ([Formula: see text], [Formula: see text] K).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!