Imaging of human tissue using noninvasive techniques has been of great interest in biomedical fields. Optical imaging has attracted a lot of attention because of its portability and economy. The possibility that a highly portable, fast, safe, and affordable imaging system which could obtain interpretable images of brain function for pre- and full-term neonates in a few seconds, has been explored in this article. We have used a sensitive optical topography system, termed phased array, in which a pair of equal-amplitude and antiphase light sources are applied to generate a sharp amplitude null and phase transition plane. This two-wavelength (750 and 830 nm), frequency encoded (50 and 52 MHz) phased array imaging system can indicate the blood concentration and oxygenation changes in blood model studies and during parietal brain activation in neonates. Significant functional responses, particularly to parietal stimulation in normal and pathological states of neonatal brain, have been revealed in our study. The preliminary clinical results are presented in this article.
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http://dx.doi.org/10.1117/1.429986 | DOI Listing |
Heliyon
July 2024
Centre for Ultrasonic Engineering, Department of Electronic and Electrical Engineering, University of Strathclyde, Glasgow, G1 1XQ, UK.
This study explores the inspection of bolted connections in wind turbines, specifically focusing on the application of Phased Array Ultrasonic Testing (PAUT). The research comprises four sections: Acoustoelastic Constant calibration, high tension investigation on bolts, blind tests on larger bolts, and Finite Element Analysis (FEA) verification. The methodology shows accurate results for stress while the bolt is under operative loads, and produces a clear indication of when it is above these loads and beginning to deform.
View Article and Find Full Text PDFSensors (Basel)
January 2025
Applied Research Laboratory, The Pennsylvania State University, State College, PA 16801, USA.
The frequency diverse array (FDA) is an architecture capable of beamforming in both range and angle, improving upon the traditional phased array (PA) which can only achieve beamforming in angle. The FDA employing directional modulation (DM) for secure directional communications (SDC) can reduce bit error rates (BERs) in both range and angle, again improving upon the traditional PA which can only reduce BER in angle. In this paper, we document the challenges involved in the design and implementation of a two-element linear FDA employing fast-time binary phase-shift keying (BPSK) modulations.
View Article and Find Full Text PDFChaos
January 2025
School of Physics and Information Technology, Shaanxi Normal University, Xi'an 710062, China.
Arrhythmia of the heart is a dangerous and potentially fatal condition. The current widely used treatment is the implantable cardioverter defibrillator (ICD), but it is invasive and affects the patient's quality of life. The sonogenetic mechanism proposed here focuses ultrasound on a cardiac tissue, controls endogenous stretch-activated Piezo1 ion channels on the focal region's cardiomyocyte sarcolemma, and restores normal heart rhythm.
View Article and Find Full Text PDFUltrasonics
December 2024
School of Mechatronic & Automation Engineering, Shanghai University, Shanghai 200444, China; Key Laboratory of Silicate Cultural Relics Conservation (Shanghai University), Ministry of Education, China. Electronic address:
Fiber reinforced polymer composites (FRPs) are essential for various industrial fields, but wrinkles inside will greatly reduce their mechanical properties. Full-matrix capture (FMC) is a popular data structure for ultrasonic phased array imaging in composites. However, such structure may lead to data redundancy and noise interference.
View Article and Find Full Text PDFLight Sci Appl
January 2025
Zhangjiang Laboratory, Shanghai, 201204, China.
Boasting superior flexibility in beam manipulation and a simpler framework than traditional phased arrays, terahertz metasurface-based phased arrays show great promise for 5G-A/6G communication networks. Compared with the reflective reconfigurable intelligent surface (reflective RIS), the transmissive RIS (TRIS) offers more feasibility for transceiver multiplexing systems to meet the growing demand for high-performance beam tracking in terahertz communication and radar systems. However, the terahertz TRIS encounters greater challenges in phase shift, beam efficiency, and complex circuitry.
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