A system for the measurement and visualization of small displacements has been developed that features high sensitivity and acoustic-wavelength-limited resolution over apertures as large as 15 cm at frequencies up to 10 MH(z). Acoustic-wave displacement amplitudes as small as 0.07 A are measured by interferometrically detecting the motion of a thin, acoustically transparent, metallized pellicle as the ultrasonic wave passes through it. The system can also be adapted to measure and display any small vibratory motion. The basic arrangement is that of the Michelson interferometer with the addition of an open-loop method to stabilize the response and a deflection system in one leg of the interferometer to scan the pellicle. Presently, the system is used in the study of the interactions of ultrasonic waves with biologic tissue and the observation and measurement of radiation patterns of acoustic transducers.
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http://dx.doi.org/10.1364/AO.15.001499 | DOI Listing |
Plant Foods Hum Nutr
January 2025
Instituto de Ciencia y Tecnología de Alimentos Córdoba (ICYTAC) - CONICET-UNC, Av. Juan Filloy S/N, Ciudad Universitaria, Córdoba, Argentina.
The focus of this work was to evaluate the differences between the thermal and mechanical effects generated by ultrasound waves on the properties of corn starch, which facilitate the subsequent enzymatic hydrolysis for the generation of porous starches. The results showed that both the thermal and mechanical effects have the capacity to disorganize/alter the structure of starch, impacting on its properties. Characteristics such as particle size, pasting and thermal properties (peak viscosity 1400-1800 cp.
View Article and Find Full Text PDFJ Nanobiotechnology
January 2025
Department of Ultrasound, Fujian Medical University Union Hospital, 29 Xinquan Road, Fuzhou, China.
Early diagnosis of pancreatic ductal adenocarcinoma (PDAC) is challenging because of its depth, which often leads to misdiagnosis during ultrasound examinations. The unique PDAC tumor microenvironment (TME) is characterized by significant fibrous tissue growth, and high interstitial pressure hinders drug penetration into tumors. Additionally, hypoxia and immune suppression within the tumor contribute to poor responses to radiotherapy and chemotherapy, ultimately leading to an unfavorable prognosis.
View Article and Find Full Text PDFSci Rep
January 2025
Laboratory of Pharmacology, Department of Pharmacy, Faculty of Pharmaceutical Sciences, Tokyo University of Science, Chiba, Japan.
Recently, exposure to sounds with ultrasound (US) components has been shown to modulate brain activity. However, the effects of US on emotional states remain poorly understood. We previously demonstrated that the olfactory bulbectomized (OBX) rat depression model is suitable for examining the effects of audible sounds on emotionality.
View Article and Find Full Text PDFSensors (Basel)
January 2025
Department of Mechanical Engineering, University of Siegen, Paul-Bonatz-Straße 9-11, 57076 Siegen, Germany.
This work leverages ultrasonic guided waves (UGWs) to detect and localize damage in structures using lightweight Artificial Intelligence (AI) models. It investigates the use of machine learning (ML) to train the effects of the damage on UGWs to the model. To reduce the number of trainable parameters, a physical signal processing approach is applied to the raw data before passing the data to the model.
View Article and Find Full Text PDFMolecules
January 2025
Key Laboratory of Forest Plant Ecology of Ministry of Education, Northeast Forestry University, Hexing Road 26, Harbin 150040, China.
(ASC) contains a variety of bioactive compounds and serves as an important traditional Chinese medicinal resource. However, its prolonged growth cycle and reliance on wild populations limit its practical use. To explore the potential of (ASF) as an alternative, this study focused on optimizing the extraction process and assessing the bioactivity of stem extracts.
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