The velocity by which the disturbance travels through the medium is the wave velocity. Pulse wave velocity is one of the main parameters in hemodynamics. The study of wave propagation through the fluid-fill elastic tube is of great importance for the proper biophysical understanding of the nature of blood flow through of cardiovascular system. The effect of viscosity on the pulse wave velocity is generally ignored. In this paper we present the results of experimental measurements of pulse wave velocity (PWV) of compression and expansion waves in elastic tube. The solutions with different density and viscosity were used in the experiment. Biophysical model of the circulatory flow is designed to perform measurements. Experimental results show that the PWV of the expansion waves is higher than the compression waves during the same experimental conditions. It was found that the change in viscosity causes a change of PWV for both waves. We found a relationship between PWV, fluid density and viscosity.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.jbiomech.2015.09.016 | DOI Listing |
Glob Heart
January 2025
Spirituality and Cardiovascular Medicine Department, Brazilian Cardiology Society -DEMCA/SBC, Brasil.
Background: Emerging evidence suggests that spirituality improves patient outcomes, however, this has undergone only limited evaluation in randomized trials. Hypertension is a major cause of cardiovascular morbidity and mortality worldwide.
Objectives: To evaluate whether a spirituality-based intervention, compared to a control group, can reduce blood pressure (BP) and improve endothelial function after 12 weeks in patients with mild or moderate hypertension (HTN).
Zhonghua Yi Xue Za Zhi
January 2025
Department of Urology, Henan Joint International Pediatric Urodynamic Laboratory, the First Affiliated Hospital of Zhengzhou University, Zhengzhou450002, China.
To comprehensively evaluate the structure and function of the bladder wall in children using multi-modal ultrasound (MMU). A total of 110 children without urinary symptoms admitted to the First Affiliated Hospital of Zhengzhou University from January 2022 to June 2023 were included prospectively. MMU was performed and the vesical volume (VV), bladder wall thickness (BWT), shear wave velocity (SWV) of the anterior wall, resistance index (RI) and vascularization index (VI) were measured in the filled and emptied bladder respectively, and the ultrasound bladder compliance (UBC) was also calculated.
View Article and Find Full Text PDFAm J Kidney Dis
January 2025
Department of Epidemiology and Welch Center for Prevention, Epidemiology, and Clinical Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA. Electronic address:
Rationale & Objective: Arterial stiffness is associated with prevalent chronic kidney disease (CKD). Whether arterial stiffness is prospectively associated with incident CKD is inconclusive.
Study Design: Longitudinal cohort study.
Ultrasonics
January 2025
Federal State Budgetary Institution , Technological Institute for Superhard and Novel Carbon Materials of National Research Centre, Kurchatov Institute, 108840 Moscow, Troitsk, Russian Federation.
Microwave surface and Lamb waves in a multilayered piezoelectric "Al-IDT/(AlSc)N/(001)[110] diamond" structure designed as a SAW resonator were studied using both the experimental and modeling methods. In this structure, it is possible to generate Rayleigh, surface horizontal (SH) and Lamb waves simultaneously. The successful excitation of Lamb waves at operating frequencies up to 20 GHz has been obtained.
View Article and Find Full Text PDFJ Cereb Blood Flow Metab
January 2025
Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, UK.
To what extent sildenafil, a selective inhibitor of the type-5 phosphodiesterase modulates systemic redox status and cerebrovascular function during acute exposure to hypoxia remains unknown. To address this, 12 healthy males (aged 24 ± 3 y) participated in a randomized, placebo-controlled crossover study involving exposure to both normoxia and acute (60 min) hypoxia (Fi = 0.14), followed by oral administration of 50 mg sildenafil and placebo (double-blinded).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!