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This paper investigates a new method to evaluate dynamic stress in plate or shell-like components due to propagation of elastic waves. The proposed method is based on collinear mixing of the stress wave with a high frequency (probe) wave, which is excited in the ultrasonic frequency range. The wave interactions generate linear and nonlinear responses such as the changes of the group velocity of the probe wave and generation of higher-order harmonics, respectively. A three-dimensional finite element (FE) model is developed to investigate and link these changes to the magnitude of the dynamic stress excited by the elastic waves. In the current work two S Lamb wave modes at relatively low and high frequences were utilised to demonstrate the proposed method, which can be extended to the measurement of dynamic stress generated by different elastic wave modes or vibrations. The numerical results have been validated by an experimental study confirming that the nonlinear effects are much more sensitive to the induced dynamic stress rather than the corresponding linear changes of the wave velocities. In addition, two parametric studies are conducted using the experimentally verified FE model. These studies are focused on the effects associated with the stress variation in the mixed region and the wavelength ratio of the probe wave to the pump waves on the dynamic stress evaluation with the proposed method.
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http://dx.doi.org/10.1016/j.ultras.2025.107801 | DOI Listing |
Med Int (Lond)
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Hunan Provincial Hospital of Integrated Traditional Chinese and Western Medicine (The Affiliated Hospital of Hunan Academy of Traditional Chinese Medicine), Changsha, Hunan 410060, P.R. China.
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September 2025
State Key Laboratory of Advanced Medical Materials and Devices, Medical College, Tianjin University, Tianjin, 300072, China.
Recent breakthroughs in tumor biology have redefined the tumor microenvironment as a dynamic ecosystem in which the nervous system has emerged as a pivotal regulator of oncogenesis. In addition to their classical developmental roles, neural‒tumor interactions orchestrate a sophisticated network that drives cancer initiation, stemness maintenance, metabolic reprogramming, and therapeutic evasion. This crosstalk operates through multimodal mechanisms, including paracrine signaling, electrophysiological interactions, and structural innervation guided by axon-derived guidance molecules.
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September 2025
Department of Pharmacology, School of Basic Medicine and Department of Pharmacy, Tongji Hospital, Tongji Medical College; and State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Huazhong University of Science and Technology, Wuhan, Hubei, 430030, China. chenjg@hu
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October 2025
Mechanical Engineering Department KVGIT Jaipur, Rajasthan, India.
Triply periodic minimal surfaces have garnered significant interest in the field of biomaterial scaffolds due to their unique structural properties, including a high surface-to-volume (S/V) ratio, tunable permeability, and the potential for enhanced biocompatibility. Bone scaffolds necessitate specific features to effectively support tissue regeneration. This study examines the permeability and active cell proliferation area of advanced Triply Periodic Minimal Surface (TPMS) lattice structures, focusing on a novel lattice design.
View Article and Find Full Text PDFMed Eng Phys
October 2025
Department of Mechanical Engineering, University of Cape Town, 7701, South Africa; Centre for Research in Computational and Applied Mechanics (CERECAM), University of Cape Town, 7701, South Africa.
The usability and versatility of autoinjectors in managing chronic and autoimmune diseases have made them increasingly attractive in medicine. However, investigations into autoinjector designs require an understanding of the kinematic properties and fluid behaviour during injection. To optimise injection efficiency, this study develops a mathematical and computational fluid dynamics (CFD) model of an IM autoinjector by investigating the effects of viscosity, needle length, needle diameter, and medication volume on the injection process.
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