Pressure Pulse Transmission Research Articles

ALGORITHM FOR EXPERIMENTAL INVESTIGATION OF HYDROIMPULSE DEVICE FOR STRENGTHENING PARTS BY DEFORMATION

In the field of mechanical engineering, various methods and techniques are typically employed for the manufacturing of workpieces or machine components. In this context, it becomes necessary to determine the principles of selection and conduct a techno-economic assessment of various possible manufacturing approaches. Typically, the choice of the most optimal technological approach for producing a specific component involves comparing the technological cost of different manufacturing methods. Plastic deformation finds a wide range of applications beyond just restoring shapes and surfaces. It is also used to improve the physical and mechanical properties of the metal's surface, enhance roughness, and increase corrosion resistance. Plastic deformation is often combined with methods of metal buildup, such as welding, cladding, and others, to enhance the yield strength and, consequently, the service life of components. This process significantly enhances the reliability and durability of products and structures subjected to plastic deformation and metal buildup. This article presents a study aimed at identifying patterns that arise when changing the operating parameters of a high-speed hydroimpulse device designed for the deformation strengthening of parts. The influence of adjusting the parameters of the pressure pulse generator on the device's characteristics is investigated. The compliance of the vibration loading parameters of the striker, such as amplitudes and frequencies, with the specified values is verified. The change in the frequency of pressure pulse transmission in the pressure cavity of the drive due to changes in feed rate is analyzed. The capabilities of the technical equipment of the hydroimpulse device for the deformation strengthening of parts are assessed. The compatibility of the hydroimpulse device with the technology of deformation strengthening of parts is studied. Mechanical characteristics of objects before and after processing with the hydroimpulse device are compared. Conclusions are drawn based on the obtained results.

Pressure Pulse Transmission and Reflection from Layer in Porous Medium with Variable Initial Content of Gas Hydrate

Pressure Pulse Transmission and Reflection from Layer in Porous Medium with Variable Initial Content of Gas Hydrate

Reflection and Transmission of Pressure Pulses Through a Gas Hydrate-Saturated Layer in a Porous Medium

Reflection and Transmission of Pressure Pulses Through a Gas Hydrate-Saturated Layer in a Porous Medium

Inflation-extension behaviour of 3D printed elastomer tubes and their constitutive description

It is known that arteries in situ are axially prestretched. This can be proved during an autopsy when a cylindrical segment of an artery is removed from a body. The segment retracts to ex situ length, and the ratio of in situ length to ex situ length defines the amount of prestretching. Ex vivo inflation-extension experiments showed that axial prestretching is advantageous from a mechanical point of view because it minimizes the longitudinal movement of an artery during pressure pulse transmission. Furthermore, calculations suggested that axial prestretching decreases variation of axial stress and makes the radial distension of arteries easier. Recently, it has been shown theoretically that axial prestretching of a nonlinear tube increases the volume, which it is able to accommodate during pressurization. The present study complements previous results with the experimental observation of this fact. Tango Plus tubes, made with the help of 3D printing PolyJet technology, were cyclically pressurized. Axial prestretching was induced by hanging weights on the vertically oriented tubes. The results showed that the internal volume of the tubes increased with the elevated axial prestretch. The recorded mechanical responses were utilized in the regression analysis to identify the material parameters of the tubes. It was found that the hyperelastic Ogden model is suitable for describing the mechanical behaviour of the Tango Plus material. Our study demonstrates that 3D printing can be used to produce tubes, which, for example, may serve as a substitute for biological tissues in laboratory experiments. Simultaneously, this study yields the constitutive parameters of the digital material identified at multiaxial stress conditions. Such parameters are necessary, for instance, in the finite element analyses of parts undergoing loading conditions which result in multiaxial stress states.

Modeling of Wave Propagation in Drilling Fluid

The study presents a one-dimensional (1D) numerical model of wave propagation as well as transmission/reflection phenomena in Newtonian and non-Newtonian drilling mud flow associated with oil/gas drilling activities. Propagation of wave formed due to back pressure changes by means of a choke is investigated. In general, the reflection and transmission of pressure waves at intersection of conduits with different cross sections or in case of partial blockage typical of drilling practices is multidimensional and caused by nonuniform boundary conditions over the cross section. The 1D approach is investigated to approximate the multidimensional reflection and transmission of pressure pulse at areal discontinuity in conduit. The approach is facilitated by introduction of a local force exerted by solid wall on the fluid at the intersection of the conduits into conservative form of the equation for momentum conservation. In addition, nonconservative formulation of momentum equation was explored. To solve the differential equations, MacCormack numerical scheme with second-order accuracy is applied to the nonlinear Euler and 1D viscous conservation equations. A grid refinement study is performed. It is shown that nonconservative form of the conservation laws results in more accurate prediction of transmission and reflection in case of areal discontinuity. The results of the numerical modeling are presented in terms of pressure wave propagation and attenuation upon reflection and transmission at consequent interfaces.

Contaminación bacteriana transitoria de un acuífero de doble porosidad en Walkerton, Ontario, Canadá

Contamination of the Paleozoic carbonate aquifer at Walkerton (Ontario, Canada) by pathogenic bacteria following heavy rain in May 2000 resulted in 2,300 illnesses and seven deaths. Subsequent tracer testing showed that there was rapid groundwater flow in the aquifer, and also rapid exchange between the aquifer and the ground surface. Electrical conductivity (EC) profiling during a 3-day pumping test showed that most flow was through bedding-plane fractures spaced about 10 m apart, that there were substantial contrasts in EC in the major fracture flows, and that there were rapid changes over time. Total coliform sampling revealed transient groundwater contamination, particularly after heavy rain and lasting up to a few days. These characteristics can be understood in terms of the dual-porosity nature of the aquifer. Most of the storage is in the matrix, but this can be considered to be static in the short term. Almost all transport is through the fracture network, which has rapid groundwater flow (∼100 m/day) and rapid transmission of pressure pulses due to the high hydraulic diffusivity. Rapid recharge can occur through thin and/or fractured overburden and at spring sites where flow is reversed by pumping during episodes of surface flooding. These characteristics facilitated the ingress of surface-derived bacteria into the aquifer, and their rapid transport within the aquifer to pumping wells. Bacterial presence is common in carbonate aquifers, and this can be explained by the well-connected, large-aperture fracture networks in these dual-porosity aquifers, even though many, such as at Walkerton, lack karst landforms.

Age-related changes in longitudinal prestress in human abdominal aorta

Studies on the influence of aging on the longitudinal mechanical response of elastic arteries are rare, though longitudinal behavior may have a significant effect on pressure pulse transmission. Our study was designed to elucidate how aging is reflected in changes of the longitudinal prestress, prestretch, and pretension force. The study involved ten human samples (six female and four male) of the abdominal aorta with longitudinal prestretch determined in autopsy. Cylindrical samples underwent a longitudinal elongation test in order to estimate the force necessary to attain the in situ length and to determine the corresponding axial prestress. The elastic modulus was estimated employing hyperelastic limiting chain extensibility model. It was found that pretension force, longitudinal prestress, and prestretch are negatively correlated with age. The decreased longitudinal force necessary to obtain the in situ length suggested that the decrease in the prestress occurs not only due to the age-related increase in the cross-section area. Since elastin is the main constituent responsible for bearing the prestretch, this suggests that the observed decrease in the longitudinal prestress and prestretch reflects aging-induced damage to the elastin. Finally, constitutive modeling showed that limiting chain extensibility is a concept that is suitable for describing the aging effect.

Wireless Wellbore - The Way Ahead

Technology Update The trend of increasing wellbore complexity for extended reservoir contact and greater reservoir heterogeneity demands improved monitoring and control solutions. Traditionally, the only option has been the deployment of a cabled system, but this limits the application of intelligent well technology to new installations or workovers. In any case, cabled systems are not always possible in new installations, especially where the completion is discontinuous, and slimhole or monobore completions may not allow cables to be deployed along the tubing string. Wireless technology is proving to be a more flexible alternative to addressing the issues of permanent downhole monitoring. Tendeka’s wireless gauge, an interventionless completion technology that has been successfully deployed in the North Sea, allows real-time flowing bottomhole pressure (FBHP) to be efficiently transmitted to the surface, an attractive option for wells, in which the cabled gauge system has failed or was not initially installed. Originally designed to 3.5 in., the company has recently produced a 2.25 in. version. Benefits of Wireless Technology The system transmits data from the lower completion to the surface via pressure pulses. The tool design allows the well’s production to be partially choked for a short time to create a pressure pulse, which is detectable on the surface pressure gauge. The well’s energy is used to transmit data to surface, thereby reducing power consumption, and the system requires no additional surface installation or pickup because an existing tubing head pressure gauge can be used to detect the pulse train. For most operators, the system can be deployed by a single intervention, allowing highly accurate data to be sourced almost instantaneously for a fraction of the cost of a recompletion. Compared with a memory gauge system, it allows data to be collected in real time and provides a continuous confirmation of operation. The gauge can be set in blank pipe, giving optimal freedom for installation depth, and it can be installed as close to the producing interval as required. A benefit of using pressure pulse transmission is the ease of installation. No retrofitting of topside equipment is required, and many of the technical and contractual issues are avoided when introducing a new monitoring system. Successful Deployment A major operator in the North Sea retrofitted the 3.5 in. wireless pressure and temperature gauge at 2200 m in a low-pressure (32 bar) gas well offshore Norway. The existing wellhead pressure sensor was used to capture the wireless signal and extract the data, therefore, no extra infrastructure was required. The application was especially challenging because the well was a marginal producer and the wellhead pressure had large background pressure variations, because of limited well deliverability. Despite these conditions, pressure pulse transmission proved effective. Even if the well starts to significantly deplete while the wireless downhole gauge is installed, the gauge itself will modify its pressure pulsing method to ensure that a detectable pulse train is transmitted to surface.

Vibrating polymeric microsieves: Antifouling strategies for microfiltration

Constant flux performance in time is achieved with polyethersulfone (PES) polymeric microsieves when filtering protein solutions, skimmed milk and white beer in combination with backpulsing. Such microsieves are fabricated by phase separation micromolding (PSμM) and possess pores around 2 μm. The filtration of bovine serum albumin (BSA) solutions at neutral pH results in constant flux when backpulsing. The constant flux performance is related to the ability of polymeric microsieves to flex during permeate pressure pulsing. Their flexibility allows pressure pulse transmission to the feed and, therefore, almost no flow reversal occurs. The membrane motion affects the hydrodynamics in the feed channel and disturbs the polarization layer and the cake deposited. Reference experiments with stiff Si x N y -based microsieves, nuclepore and macroporous microfiltration membranes show different behavior: the permeate pressure pulse hardly translates into the feed channel. Backpulsing for these membranes is less effect as anti-fouling strategy. Backpulsing of polymeric microsieves also allows stable flux operation for other complex feeds like skimmed milk and white Belgian beer.

Viscoelastic effects in pressure transduction

Pressure measurements in flows of highly viscous and elastic fluids are of practical importance in many manufacturing processes. Problems may arise during such pressure measurements, since high fluid viscosity and elasticity result in excessive dynamic response time of the pressure measuring systems as well as in some distortion. This is true for systems that consist of manometers as well as pressure transducers. In this work we develop an analytical model for the pressure pulse transmission in columns of viscoelastic fluids leading to pressure transducers. Basic equations are derived and analytical solutions are illustrated for a square wave pulse. Predictions of the model can be utilized to interpret correctly pressure transducer readings in fluid systems exhibiting viscoelastic behavior.

The effects of metronome breathing on the variability of autonomic activity measurements

Background: Many chiropractors hypothesize that spinal manipulation affects the autonomic nervous system (ANS). However, the ANS responses to chiropractic manipulative therapy are not well documented, and more research is needed to support this hypothesis. This study represents a step toward the development of a reliable method by which to document that chiropractic manipulative therapy does affect the ANS by exploring the use of paced breathing as a way to reduce the inherent variability in ANS measurements. Objective: To examine the hypothesis that the variability of ANS measurements would be reduced if breathing were paced to a metronome at 12 breaths/min. Setting: The study was performed at Parker College Research Institute. Eight normotensive subjects were recruited from the student body and staff. Methods: Respiration frequency was measured through a strain gauge. A 3-lead electrocardiogram (ECG) was used to register the electric activity of the heart, and arterial tonometry monitors were used to record the left and right radial artery blood pressures. Signals were recorded on an IBM-compatible computer with a sampling frequency of 100 Hz. Normal breathing was used for the first 3 recordings, and breathing was paced to a metronome for the final 3 recordings at 12 breaths/min. Fourier analysis was performed on the beat-by-beat fluctuations of the ECG-determined R-R interval and systolic arterial pressure (SBP). Low-frequency fluctuations (LF; 0.04-0.15 Hz) reflected sympathetic activity, whereas high-frequency fluctuations (HF; 0.15-0.4 Hz) represented parasympathetic activity. Sympathovagal indices were determined from the ratio of the two bandwidths (LF/HF). The coefficient of variation (CV%) for autonomic parameters was calculated ([average/SD] × 100%) to compare breathing normally and breathing to a metronome with respect to variability. One-way analysis of variance was used to detect differences. A value of P <.05 was considered statistically significant; all results are presented as average ± SD. Results: Three male and 5 female normotensive subjects were studied. Metronome breathing did not produce any significant changes in blood pressure for the left and right radial arteries, heart rate, or pressure pulse transmission time. Breathing to a metronome increased ECG-HF power (0.25 ± 0.07 vs 0.35 ± 0.09, P <.04), decreased ECG-LF/HF (1.08 ± 0.55 vs 0.57 ± 0.35, P <.05), and reduced the CV% for ECG-LF (47.6% ± 23.4% vs 23.8% ± 14.6%, P <.03), ECG-HF (46.2% ± 14.2% vs 25.8% ± 17.0%, P <.03) and ECG-LF/HF (50.1% ± 27.6% vs 23.4% ± 12.3%, P <.03) in comparison with normal breathing. Metronome breathing increased the left and right radial artery SBP-HF fluctuations (left, 0.11 ± 0.05 vs 0.30 ± 0.16, P <.007; right, 0.09 ± 0.05 vs 0.27 ± 0.15, P <.008) and decreased the SBP-LF/HF components (left, 3.42 ± 2.36 vs 1.14 ± 0.88, P >.03; right, 3.08 ± 1.77 vs 1.20 ± 0.93, P <.02). Metronome breathing did not significantly alter the CV% for SBP-HF, SBP-LF, and SBP-LF/HF. Conclusions: Metronome breathing increased parasympathetic activity, as evidenced by augmented HF power in the ECG and SBP data. The variability (CV%) of ECG-determined ANS measurements was significantly reduced with paced breathing at 12 breaths/min, but no significant reductions were observed for the SBP-determined ANS measurements. These findings indicate that ECG data are more sensitive than SBP data for future clinical trials. (J Manipulative Physiol Ther 2000;23:610-4)

Effects of spinal manipulative therapy on autonomic activity and the cardiovascular system: A case study using the electrocardiogram and arterial tonometry

Objective: To determine if there is alteration in the autonomic nervous and cardiovascular systems after chiropractic manipulative therapy (CMT). A novel approach was used to quantitatively probe for changes in the activity of the autonomic nervous system, in blood pressure, and in pressure pulse transmission time. This approach uses the electrocardiogram and arterial tonometry equipment. Design: This case study involves 1 subject treated over a 6-week period (2 visits/week). Respiration, electrocardiogram, and left and right radial artery blood pressures were measured during the baseline (2 visits) and treatment (10 visits) phases. Measurements were obtained before (n = 3) and after (n = 3) a break period (baseline) or before and after CMT. High-velocity, low-amplitude CMT that produced joint cavitation was used. Setting: The study was performed at the Parker College Research Institute in a temperature-controlled laboratory. Main Outcome Measures: Fourier analysis was performed on the electrocardiogram-determined rest-redistribution intervals. The low frequency power between 0.04 to 0.15 Hz and the high frequency power between 0.15 to 0.40 Hz represent the activity of the sympathetic and parasympathetic nervous systems, respectively. The main outcome measure was the sympathovagal index, which is determined from the ratio of low frequency to high frequency. The arterial pressure and the time for pressure pulses to travel from the heart to the radial artery recording sites (pressure pulse transmission time) were studied. Differences (average of 3 measurements after treatment minus measurements before treatment) for each variable were calculated. Results: After the 1st CMT treatment, the difference between treatment and baseline decreased for both the low frequency/high frequency (-2.804 ± 1.273) and low frequency power (-0.135 ± 0.056). These findings indicated that the parasympathetic nervous system predominated the sympathetic nervous system. After the 3rd, 4th, 6th, and 9th treatment, the difference between treatment and baseline increased for low frequency/high frequency (0.908 ± 0.338, 2.313 ± 0.300, 2.776 ± 1.102, and 0.988 ± 0.269, respectively) and indicated that the sympathetic nervous system predominated the parasympathetic nervous system. In addition, the difference between treatment and baseline for the pressure pulse transmission time decreased bilaterally after the 4th treatment (left, -13.52 ± 3.70 ms; right, -9.75 ± 3.76 ms) and 6th treatment (left, -9.53 ± 3.60 ms; right, -9.24 ± 3.50 ms), which indicated that arterial compliance had decreased. Furthermore, after the 6th treatment, the difference between treatment and baseline for the rest-redistribution interval time decreased (-0.084 ± 0.014 s). The difference between treatment and baseline for the systolic, diastolic, and mean arterial pressure for the above-mentioned treatments was not considered significant. Conclusion: This case study is the first to attempt to use electrocardiogram and arterial tonometry data to study the effects of CMT on the autonomic nervous and cardiovascular systems over an extended period of time. These devices allowed a more in-depth study of the cardiovascular and autonomic changes associated with CMT. Although changes in the autonomic nervous and cardiovascular systems can be detected, further development of a reliable and reproducible experimental protocol is required before validating the effects of CMT on these systems. (J Manipulative Physiol Ther 2000;23: 545-50)

Magma chamber and eruptive processes at Izu-Oshima volcano, Japan: buoyancy control of magma migration

Underground magmatic processes are modeled for a sequence of eruptions that started on November 15, 1986 at Izu-Oshima volcano. It is predicted from the seismic gap, the seismic velocity structure, the deformation center and the gravity minimum that there should be a magma chamber at a depth of about 4 km beneath the northwestern flank of the volcano. The effusion of basalt that began at the summit crater established a well-connected conduit system between the magma chamber and the summit crater. The following eruption from new fissures a few days later produced more felsic and less homogeneous compositions, basaltic andesite to andesite, because of cooling and fractional crystallization of ascending magma. Subsequently, four small eruptions were caused by gravitational sliding of sluggish, semisolid magma into openings in and along the sides of the shallow conduit as magma was returning to the magma chamber. Systematic tilt changes due to transmission of pressure pulses from the summit crater to the magma chamber were observed during a small explosion on November 18, 1987 and for many periods of episodic volcanic tremor. The migration of magma is interpreted to have been driven by a buoyancy force associated with bubbles in the magma. In this regard, dominant ascent of magma beneath the summit crater and new fissures in November 1986 was triggered by vesiculation of volatiles in the magma, and the subsequent return flow of magma resulted from the release of bubbles through degassing. The observed response of volcanic processes following earthquake swarms northwest of the island is also explained by buoyancy-controlled magma migration that could intensify the effect of small fluctuations in the crustal stress.

Haemodynamic modelling for the arterial pulsatile component of the intracranial pulse wave

Vasospasm of cerebral arteries narrows the amplitude of the intracranial pressure wave, indicating that the arterial segment of the cerebral circulation is partially responsible for its formation. We investigated the fundamental mechanism of pressure pulse transmission from an artery to the surrounding environment. A mathematical model was derived expressing the amplitude of container pulsation (delta Po) as a function of mean intraluminal pressure (MPi), mean container pressure (MPo) and arterial pulse amplitude (delta Pi): delta Po = (-2(MPi - MPo) + b) (MPo + 1) delta Pi. This mathematical model was experimentally validated using an in vivo system of a single artery sealed inside a fluid-filled elastic container.

Role of viscosity in frequency-dependent reflection from discontinuities in liquid-filled tubes.

The paper investigates the effect of fluid viscosity on wave reflection at sites of geometric and/or mechanical discontinuity in a system of liquid-filled tubes, when the transmission of pressure pulses along these tubes is governed by a linear medium wavelength (LMW) theory. This theory is capable of describing the propagation of pressure impulses that contain frequencies in the range 0–500 Hz. We derive formulae for the reflection coefficients at a junction between two dissimilar tubes and examine the influence of fluid viscosity on these coefficients. Over much of the frequency spectrum under consideration, viscosity changes the reflection coefficients very little. The influence of viscosity is significant, however, at frequencies below 1 Hz.

Nonlinearities on the pressure pulse propagation through a straight elastic tube

The present paper describes a nonlinear mathematical model for the pressure-pulse transmission through an elastic straight tube with circular cross-section. The distortion of a sinusoidal pressure pulse in dimensionless form depends on two parameters, the Strouhal number and the Euler number. The analysis is useful to the correction of the errors which enter in the measurement of the dynamic pressure when long elastic tubes connecting the point of measurement and the pressure transducer are used.

Pressure pulse transmission into vascular beds

Observations at the microcirculatory level have revealed that (a) the pressure pulse reaches the smallest vessel, and (b) the pulse wave velocity alters from a value in the order of meters/second in large arteries to a value in the order of centimeters/second in the microvessels. We investigate, herein, whether these experimental findings are consonant with linear pulse wave transmission theory in a branching system of vessels. Our computations, utilizing available data, show that this is indeed the case. For low frequency (1 Hz), cumulative attenuation is such that about one-third of the pulse, originating at the heart, reaches the capillary. A 10-Hz pulse, however, is virtually completely attenuated by the time the cpaillary is reached. Transmission time for a pulse, from heart to capillary, is also frequency dependent, with higher frequencies propagating more rapidly. Vasoconstriction, at the arteriolar level in the absence of reflection, can also strongly attenuate the pulse remnant at that site.

Simulations of arterial pressure pulses using a transmission line model

Transmission of pressure pulses from the aorta to the central retinal artery is studied under normal and stenotic conditions. A convenient model for the study is obtained by replacing the arteries with a network of distributed electrical transmission lines. By using boundary conditions and a voltage-pressure analogy, the transmitted pulse is obtained. Stenosis of varying degrees were simulated at different locations and the characteristics of the transmitted pulse was studied by examining its peak value, the dicrotic notch and the systolic slope. The dependence of the characteristics of the transmitted pulse on the physical parameters were also studied.

Influence of transmural pressure on retrograde pressure pulse transmission velocity in the canine superior vena cava.

The influence of intrathoracic and intraluminal pressure on venous pressure pulse propagation velocity in the superior vena cava was investigated in acute canine experiments. The propagation velocity of distinct points of the venous pressure curve was measured under different conditions of preload, during expiratory and inspiratory apnea and during positive-negative pressure respiration. Under control conditions transmission velocities varied from 1.07 m/s to 3.29 m/s. After volume expansion propagation velocities rose significantly and varied from 1.09 m/s to 6.48 m/s. During expiratory apnea and at peak negative expiratory pressure, the propagation speed of distinct pressure points was higher than during inspiratory apnea and at peak positive inspiratory pressure. Significant linear correlation coefficients were found between the transmission velocities of different distinct pressure points and the transmural pressure, but not between the propagation speed and the intraluminal pressure.

Pulse wave velocity in human veins.

ArticlePulse wave velocity in human veins.J H Nippa, R H Alexander, and R FolseJ H Nippa, R H Alexander, and R FolsePublished Online:01 Apr 1971https://doi.org/10.1152/jappl.1971.30.4.558MoreSectionsPDF (2 MB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat Previous Back to Top Next Download PDF FiguresReferencesRelatedInformation Cited ByA Portable Device for the Measurement of Venous Pulse Wave Velocity19 February 2022 | Applied Sciences, Vol. 12, No. 4Applications of Intermittent Pneumatic Compression for Diagnostic and Therapeutic Purposes14 October 2021Venous Pulse Wave Velocity variation in response to a simulated fluid challenge in healthy subjectsBiomedical Signal Processing and Control, Vol. 63Objective Assessment of Venous Pulse Wave Velocity in Healthy HumansUltrasound in Medicine & Biology, Vol. 46, No. 3One-Dimensional Haemodynamic Modeling and Wave Dynamics in the Entire Adult Circulation2 April 2015 | Annals of Biomedical Engineering, Vol. 43, No. 6A global multiscale mathematical model for the human circulation with emphasis on the venous system15 January 2014 | International Journal for Numerical Methods in Biomedical Engineering, Vol. 30, No. 7Steady analysis of transcritical flows in collapsible tubes with discontinuous mechanical properties: implications for arteries and veins4 November 2013 | Journal of Fluid Mechanics, Vol. 736Structural and Functional Properties of Venous Wall: Relationship between Elastin, Collagen, and Smooth Muscle Components and Viscoelastic PropertiesISRN Physiology, Vol. 2013Transmission of Arterial Signals, Venous Nonlinearity, and Body Movement29 June 2011Wave reflection analysis of the human cerebral circulation during syncopeAutonomic Neuroscience, Vol. 132, No. 1-2Systemic venous circulation. Waves propagating on a windkessel: relation of arterial and venous windkessels to systemic vascular resistanceJiun-Jr Wang, Jacqueline A. Flewitt, Nigel G. Shrive, Kim H. Parker, and John V. Tyberg1 January 2006 | American Journal of Physiology-Heart and Circulatory Physiology, Vol. 290, No. 1Influence of transmural pressure on retrograde pressure pulse transmission velocity in the canine superior vena cava26 September 2008 | Archives Internationales de Physiologie et de Biochimie, Vol. 92, No. 4Venous System: Physiology of the Capacitance Vessels1 January 2011VeinsHemodynamic measurements in peripheral vascular diseaseCurrent Problems in Surgery, Vol. 13, No. 8Directional transcutaneous assessment of venous inflowAmerican Heart Journal, Vol. 82, No. 1 More from this issue > Volume 30Issue 4April 1971Pages 558-63 https://doi.org/10.1152/jappl.1971.30.4.558PubMed5572772History Published online 1 April 1971 Published in print 1 April 1971 Metrics