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Guo Jia J Department of Bioengineering, University of California, San Diego, La Jolla, California, - - 2014
Velocity-selective arterial spin labeling (VSASL) tags arterial blood on a velocity-selective (VS) basis and eliminates the tagging/imaging gap and associated transit delay sensitivity observed in other ASL tagging methods. However, the flow-weighting gradient pulses in VS tag preparation can generate eddy currents (ECs), which may erroneously tag the static tissue ...
Flisar Karel K University of Ljubljana, Faculty of Electrical Engineering, Laboratory of Biocybernetics, Trzaska 25, 1000 Ljubljana, Slovenia. Electronic address: - - 2014
Among other applications, electroporation is used for the inactivation of pathogens and extraction of substances from microorganisms in liquids where large scale flow systems are used. The aim of our work was therefore to test a pulse generator that enables continuous pulsed electric field (PEF) treatment for Escherichia coli inactivation ...
Tarumi Takashi T 1] Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, Texas, USA [2] Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, - - 2014
Blood ejected from the left ventricle perfuses the brain via central elastic arteries, which stiffen with advancing age and may elevate the risk of end-organ damage. The purpose of this study was to determine the impact of central arterial aging on cerebral hemodynamics. Eighty-three healthy participants aged 22 to 80 ...
Pase Matthew P MP Centre for Human Psychopharmacology, Swinburne University of Technology, Hawthorn, Australia, 3122. Electronic address: - - 2014
Low cerebral blood flow velocity is associated with cognitive decline. However, the association between pulsatile brain blood flow velocity and cognition has not been investigated. High pulsatile hemodynamic stress in the brain may impair cognitive function through damage to small cerebral vessels. The current objective was to examine the cross-sectional ...
Rossow Lindy M LM Fitchburg State University, 155 North St, Fitchburg, MA 01420, USA. Electronic address: - - 2014
Resistance training is recommended for all adults of both sexes. The arterial stiffness and limb blood flow responses to resistance training in young and older women have not been well-studied. The purpose of this study was to examine arterial stiffness and blood flow adaptations to high-intensity resistance exercise training in ...
Vrselja Zvonimir Z 1] Department of Anatomy and Neuroscience, Medical School of J. J. Strossmayer University in Osijek, Osijek, Croatia [2] Department of Radiology, Osijek University Medical Center, Osijek, - - 2014
Nearly 400 years ago, Thomas Willis described the arterial ring at the base of the brain (the circle of Willis, CW) and recognized it as a compensatory system in the case of arterial occlusion. This theory is still accepted. We present several arguments that via negativa should discard the compensatory ...
Crespo Gastón A - - 2014
We explore here for the first time a potentially calibration-free methodology for the detection of protamine (and, by titration, heparin) in undiluted human blood in the therapeutic concentration range of 20 to 120 mg L-1. The use of a thin layer sample (5.8 μL) confined between a tubular protamine selective ...
Flück Daniela D Department of Biology, Institute of Human Movement Sciences and Sport, ETH Zurich Zurich, Switzerland ; Department of Physiology and Pharmacology, Faculty of Medicine, University of Calgary Calgary, AB, - - 2014
Aging is associated with decreased vascular compliance and diminished neurovascular- and hypercapnia-evoked cerebral blood flow (CBF) responses. However, the interplay between arterial stiffness and reduced CBF responses is poorly understood. It was hypothesized that increased cerebral arterial stiffness is associated with reduced evoked responses to both, a flashing checkerboard visual ...
Lefferts Wesley K WK Department of Exercise Science, Syracuse University Syracuse, NY, - - 2014
Arterial stiffness is associated with cerebral flow pulsatility. Arterial stiffness increases following acute resistance exercise (RE). Whether this acute RE-induced vascular stiffening affects cerebral pulsatility remains unknown. To investigate the effects of acute RE on common carotid artery (CCA) stiffness and cerebral blood flow velocity (CBFv) pulsatility. Eighteen healthy men ...
Djelic Marina - - 2013
In the frame of a laboratory training course for medicine students, a new approach for laboratory exercises has been applied to teach the phenomena of circulation. The exercise program included measurements of radial artery blood flow waveform for different age groups using a noninvasive optical sensor. Arterial wave reflection was ...
Al-Khabori Murtadha - - 2013
Non-invasive hemoglobin estimation may increase the recruitment of blood donors. CO-oximetry hemoglobin estimation is a non-invasive method used to estimate the hemoglobin level. The primary objective of this study is to validate the pulse CO-oximetry based hemoglobin estimation in normal blood donors. We conducted a prospective observational study on 106 ...
- - 2013
A pulse wave is the displacement wave which arises because of ejection of blood from the heart and reflection at vascular bed and distal point. The investigation of pressure waves leads to understanding the propagation characteristics of a pulse wave. To investigate the pulse wave behavior, an experimental study was ...
Bopp Christopher M - - 2013
The associations between macrovascular and microvascular responses reported previously during post-occlusive reactive hyperemia have been inconsistent. The purpose of this study was therefore to determine the temporal relationship between the reactive hyperemic responses within a conduit artery and the downstream microvessels. Conduit artery blood flow was measured in the brachial ...
Niklas A - - 2013
Noninvasive optical methods such as photoplethysmography, established for blood pulse detection in organs, have been proposed for vitality testing of human dental pulp. However, no information is available on the mechanism of action in a closed pulp chamber and on the impairing influence of other than pulpal blood flow sources. ...
Scully Stephanie - - 2013
The aim was to characterize dominant follicle (DF) and CL development through the estrous cycle of cattle using three-dimensional (3D) ultrasonography while making a comparison with conventional two-dimensional (2D) B-mode ultrasound (US) and to relate the measures taken to systemic concentrations of steroid hormones and gonadotropins. After synchronization of estrus, ...
Kyriacou Panayiotis A - - 2013
BACKGROUND:Pulse oximetry is a noninvasive photometric technique that provides information about arterial blood oxygen saturation (Spo2) and heart rate and has widespread clinical applications. This is accomplished via peripheral pulse oximetry probes mainly attached to the finger, toe, or earlobe. The direct application of pulse oximetry to an organ, such ...
Bernal Miguel - - 2013
The assessment of coagulating blood elasticity has gained importance as a result of several studies that have correlated it to cardiovascular pathologic conditions. In this study we use supersonic shear wave imaging (SSI) to measure viscoelastic properties of blood clots. At the same time, classical rheometry experiments were carried out ...
Nebyla Marek - - 2013
We study effects of oscillatory convective flow in extracellular space on the velocity of chemical signal propagation having a form of a front wave above a cellular layer. We found that the time-averaged propagation velocity under oscillatory flow for a particular Péclet number amplitude is slower than the velocity under ...
Sone Shusaku - - 2013
We developed a simultaneous analysis system for blood pressure and flow using photoplethysmography and ultrasonic-measurement-integrated simulation. The validity of the system was confirmed by analysis of blood flow field in a carotid artery and corresponding wave intensity (WI) values.
Hashimoto Junichiro - - 2013
Aortic stiffening often precedes cardiovascular diseases, including stroke, but the underlying pathophysiological mechanisms remain obscure. We hypothesized that such abnormalities could be attributable to altered central blood flow dynamics. In 296 patients with uncomplicated hypertension, Doppler velocity pulse waveforms were recorded at the proximal descending aorta and carotid artery to ...
Jain Ashish - - 2013
Clarithromycin is an antibacterial widely used for the treatment of a myriad of infections. Various methods including HPLC have been reported for its drug plasma concentration but they are more complex. In this study, we developed an electrochemical method for estimation of clarithromycin in blood using differential pulse polarography (DPP) ...
Shi Liang - - 2013
Hemodynamic conditions play a critical role in embryonic cardiovascular development, and altered blood flow leads to congenital heart defects. Chicken embryos are frequently used as models of cardiac development, with abnormal blood flow achieved through surgical interventions such as outflow tract (OFT) banding, in which a suture is tightened around ...
Caruso Brian S - - 2013
In mountain braided rivers, extreme flow variability, floods and high flow pulses are fundamental elements of natural flow regimes and drivers of floodplain processes, understanding of which is essential for management and restoration. This study evaluated flow dynamics and invasive vegetation characteristics and changes in the Ahuriri River, a free-flowing ...
Caruso Brian S - - 2013
This study evaluated flow regimes and flood pulse characteristics, and their influences on invasive riparian vegetation, in a free-flowing braided river in the Southern Alps, South Island, New Zealand. A 46-year gauged flow record was used to evaluate 67 flow metrics for the Ahuriri River, and five sets of colour ...
Ginther O J - - 2013
On Day 16 (Day 0 = ovulation) or before the expected transition into the luteolytic period, heifers were not treated (control group, N = 7) or were treated with a single 0.1-mg dose of estradiol (E2) (E2 group, N = 6) or E2 combined with the GnRH antagonist acyline (E2/Ac ...
Gutfreund Shay - - 2013
BACKGROUND: Metabolic syndrome (MetS) is characterized by obesity, insulin resistance, dyslipidemia, and hypertension. The Retinal Function Imager (RFI) is a new technique for measuring retinal blood-flow velocity. This study aims to compare retinal blood flow velocity between MetS and healthy subjects. METHODS: Twenty eyes of 20 MetS males and 21 ...
Huang Chih-Chung - - 2013
Purpose: Measurements of the viscoelastic properties of a thrombus can be used to assess whether blood clots are likely to become occlusive or to break apart and leak into the blood circulation and block smaller vessels. An accurate method for estimating both the shear elasticity and viscosity of a blood ...
Sebbane Mustapha - - 2013
Study objective:The RAD-57 pulse CO-oximeter is a lightweight device allowing non-invasive measurement of blood carboxyhemoglobin (SpCO).We assessed the diagnostic value of pulse CO-oximetry, comparing SpCO to standard laboratory blood measurement (COHb) in emergency department (ED) patients with suspected carbon monoxide (CO) poisoning.Methods:This was a prospective, diagnostic accuracy study according to ...
Zelli R - - 2013
This study was carried out with the objectives to test the differences in the haemodynamic characteristics of the prostatic artery in normal and benign prostatic hyperplasia (BPH)-affected dogs using Doppler ultrasonography. In sixteen male German shepherd dogs, prostatic volume was detected and prostatic biopsy was performed. The prostatic artery blood ...
Yiu Billy Y S - - 2013
Realization of flow imaging at high frame rates is essential to the visualization of complex flow patterns with fast-changing spatiotemporal dynamics. In this study, we present an experimental demonstration of a novel ultrasound-based high-frame-rate flow visualization technique called color-encoded speckle imaging (CESI), which depicts flow information in a hybrid form ...
Feiner John R - - 2013
BACKGROUND:Carbon monoxide poisoning is a significant problem in most countries, and a reliable method of quick diagnosis would greatly improve patient care. Until the recent introduction of a multiwavelength "pulse CO-oximeter" (Masimo Rainbow SET® Radical-7), obtaining carboxyhemoglobin (COHb) levels in blood required blood sampling and laboratory analysis. In this study, ...
Mynard Jonathan P - - 2013
Given evidence that fully developed axisymmetric flow may be the exception rather than the rule, even in nominally straight arteries, maximum velocity (Vmax) can lie outside the Doppler sample volume (SV). The link between Vmax and derived quantities, such as volume flow (Q), may therefore be more complex than commonly ...
Kim Jongyoun - - 2013
PWV, a surrogate marker for vascular stiffness, can be also expressed by the Bramwell-Hill equation. The effect of blood density to PWV has been ignored, because variation of blood density is assumed to be negligible. In some clinical situation, blood density could be changed, and blood density as a mechanical ...
Lis Raphael - - 2013
Comment on: Rafii S, et al. Blood 2013; 121:770-80.
Langham Michael C - - 2013
ABSTRACT: BACKGROUND: The aim of this study was to develop and evaluate an integrated CMR method incorporating dynamic oximetry, blood flow and pulse-wave velocimetry to assess vascular reactivity in patients with peripheral artery disease (PAD) and healthy controls.Methods and results: The study population consisted of young healthy subjects (YH, 30 ...
Reising Ansgar - - 2013
Patients undergoing hemodialysis treatment have a six-fold increased risk for stroke relative to the general population. However, the effect of hemodialysis on cerebral blood flow is poorly studied and confounding factors like blood pressure and ultrafiltration as well as temperature changes have rarely been accounted for. The aim of our ...
Kregting Louise T - - 2013
Broadcast spawning invertebrates that live in shallow, high-energy coastal habitats are subjected to oscillatory water motion that creates unsteady flow fields above the surface of animals. The frequency of the oscillatory fluctuations is driven by the wave period, which will influence the stability of local flow structures and may affect ...
Heffernan Kevin S KS Department of Exercise Science, Syracuse University, Syracuse, NY 13244, - - 2013
Background. The contour of the common carotid artery (CCA) blood flow velocity waveform changes with age; CCA flow velocity increases during late systole, and this may contribute to cerebrovascular disease. Late systolic flow velocity augmentation can be quantified using the flow augmentation index (FAIx). We examined hemodynamic correlates of FAIx ...
Zhang X - - 2012
The longitudinal relaxation time of blood is a crucial parameter for quantification of cerebral blood flow by arterial spin labeling and is one of the main determinants of the signal-to-noise ratio of the resulting perfusion maps. Whereas at low and medium magnetic field strengths (B(0) ), its in vivo value ...
Van Canneyt Koen - - 2012
Purpose: Maturation of an arterio-venous fistula (AVF) frequently fails, with low post-operative fistula flow as a prognostic marker for this event. As pulsed wave Doppler (PWD) is commonly used to assess volume flow, we studied the accuracy of this measurement in the setting of a radio-cephalic AVF. Methods: As in-vivo ...
Park Yong-Hee YH Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, 101 Daehakno, Jongnogu, Seoul 110-744, - - 2012
The most common method for determining the hemoglobin concentration is to draw blood from a patient. However, the Radical-7 Pulse CO-Oximeter (Masimo Corporation, Irvine, CA) can noninvasively provide continuous hemoglobin concentration (SpHb). In our study we compared noninvasive measurements of SpHb with simultaneous laboratory measurements of total hemoglobin in arterial ...
Bardon Petr - - 2012
Objectives- Ultrasound has various biological effects in the human body. The effects of continuous monitoring with ultrasound (sonolysis) on vasodilatation of the radial artery were described recently. We wanted to ascertain whether similar changes in the blood flow velocity during sonolysis could also be detected in the middle cerebral artery. ...
Chen Yong - - 2012
Ultrasonic flow meter with non-invasive no-moving-parts construction has good prospective application for space on-orbit fluid gauging. In traditional pulse transit time flow meter, inconsistency of ultrasonic transducers leads to measurement error and plane wave theory, bases of transit time flow meter, is valuable only for low-frequency wave propagation in inviscid ...
Nduom Edjah K - - 2012
Object Although pulsatile and continuous infusion paradigms have been described for convective delivery of drugs, the effectiveness and properties of each flow paradigm are unknown. To determine the effectiveness and properties of pulsatile and continuous convective infusion paradigms, the authors compared these convective flow methods in the gray and white ...
Peffer Karlijn - - 2012
BACKGROUND: Iron catalyzes the formation of free radicals, which could lead to damaged vascular walls and subsequent atherosclerosis. Blood donation decreases iron stores and can thus decrease cardiovascular risk. Even within blood donors, differences in stored iron are observed. This study investigates whether increasing lifetime number of donations decreases the ...
Attar Tarik - - 2012
The objective is the determination of the conditions operating optimal to determine the concentration of the cadmium and the lead dissolved in the human blood. An electroanalytical method has been developed for the determination of lead and cadmium in whole blood by differential pulse anodic stripping voltammetry (DPASV) on a ...
Uppaluri Sravanti - - 2012
The dynamics of isolated microswimmers are studied in bounded flow using the African trypanosome, a unicellular parasite, as the model organism. With the help of a microfluidics platform, cells are subjected to flow and found to follow an oscillatory path that is well fit by a sine wave. The frequency ...
Chandrasekhar Anand - - 2012
Noninvasive evaluation of arterial compliance by measurement of Pulse Wave Velocity (PWV) has proven utility in cardiovascular screening. We present the design of a novel Magnetic PlethysmoGraph (MPG) for non-invasive estimation of PWV. The system uses a Giant Magneto Resistance (GMR) sensor to detect the fluctuations caused by blood flow ...
Nuriya Mutsuo - - 2012
Molecular diffusion in the extracellular space (ECS) plays a key role in determining tissue physiology and pharmacology. The blood-brain barrier regulates the exchange of substances between the brain and the blood, but the diffusion properties of molecules at this blood-brain interface, particularly around the astrocyte endfeet, are poorly characterized. In ...
Calvetti Daniela - - 2012
This work is a computational study based on a new detailed metabolic network model comprising well-mixed compartments representing separate cytosol and mitochondria of astrocytes, glutamatergic and gamma aminobutyric acid (GABA)ergic neurons, communicating through an extracellular space compartment and fed by arterial blood flow. Our steady-state analysis assumes statistical mass balance ...
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