The transient radiation of low-frequency elastic waves through isotropic and homogeneous soft media is investigated using the Green's function approach. A careful analysis of the coupling term is performed and yields the introduction of a very near field region in which its amplitude behaves as 1/r. To address the calculation of impulse responses, a simplified Green's function is proposed for semi-infinite media and compared to exact solutions. Impulse response calculations are successfully compared with experimental measurements obtained for circular radiators of different diameters using transient elastography. Results presented in this paper provide a better understanding of the role of the coupling term in elastography and should be used to compensate diffraction and coupling effects observed in transient elastography.
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http://dx.doi.org/10.1121/1.1635412 | DOI Listing |
J Neurol
January 2025
Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
Background: Married or long-term partnered patients with chronic diseases generally have better outcomes than unmarried patients, likely due to the potential for multifaceted support. However, the impact of marital status on multiple sclerosis (MS) radiographic disease burden is currently unknown.
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Macromol Rapid Commun
January 2025
Qingdao Innovation and Development Center, Harbin Engineering University, Qingdao, 266000, China.
Hydrogels are flexible materials characterized by a 3D network structure, which possess high water content and adjustable physicochemical properties. They have found widespread applications in tissue engineering, electronic skin, drug delivery, flexible sensors, and photothermal therapy. However, hydrogel networks often exhibit swelling behavior in aqueous environments, which can result in structural degradation and a loss of gel performance.
View Article and Find Full Text PDFMol Genet Metab Rep
March 2025
Alnylam Pharmaceuticals, Maidenhead, UK.
Background: Acute hepatic porphyria (AHP) is characterized by debilitating and potentially life-threatening neurovisceral attacks, possible chronic symptoms, and long-term complications. In a phase 1/2 open-label extension (OLE) study and the phase 3 ENVISION study, givosiran led to sustained improvement in annualized attack rate and quality of life (QOL) measures. To capture the patient experience of symptoms and impacts of AHP, and any changes experienced during treatment with givosiran, qualitative interviews were conducted with study participants.
View Article and Find Full Text PDFComput Med Imaging Graph
December 2024
Medical Image and Data Analysis (MIDAS.lab), Department of Diagnostic and Interventional Radiology, University of Tuebingen, Tuebingen, Germany.
Cardiac Cine Magnetic Resonance Imaging (MRI) provides an accurate assessment of heart morphology and function in clinical practice. However, MRI requires long acquisition times, with recent deep learning-based methods showing great promise to accelerate imaging and enhance reconstruction quality. Existing networks exhibit some common limitations that constrain further acceleration possibilities, including single-domain learning, reliance on a single regularization term, and equal feature contribution.
View Article and Find Full Text PDFJ Neurosci Nurs
January 2025
Soomin Lim, MD RN, College of Nursing, Seoul National University, Seoul, Korea.
BACKGROUND: Patients with brain tumors continue to exhibit a lower quality of life than the general population, even after an extended period after surgery. Therefore, this study aimed to assess the postoperative quality of life of patients with brain tumors in South Korea and explore its determinants. METHODS: This study used a descriptive correlational design and collected data using questionnaires and electronic medical records.
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