44,709 results match your criteria pressure velocity


Sports compression garments improve resting markers of venous return and muscle blood flow in male basketball players.

J Sport Health Sci 2021 Jul 24. Epub 2021 Jul 24.

Institute for Health and Sport (iHeS), Victoria University, Footscray, VIC 3011, Australia; Department of Physiology, Australian Institute of Sport, Bruce, ACT 2617, Australia.

Background: The benefits associated with sports compression garments are thought to be closely related to enhanced blood flow. However, findings are equivocal, possibly due to heterogeneity in techniques used for measuring blood flow, garment types used, and pressures applied. This study combined Doppler ultrasound and near-infrared spectroscopy technologies to provide the first comprehensive assessment of the effects of three sports compression garment types on markers of venous return and muscle blood flow at rest. Read More

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Effects of enhanced versus reduced vasodilating treatment on brachial and central blood pressure in patients with chronic kidney disease: a randomized controlled trial.

J Hypertens 2021 Jul 23. Epub 2021 Jul 23.

Department of Renal Medicine, Aarhus University Hospital Comparative Medicine Lab, Department of Clinical Medicine, Aarhus University Department of Cardiology, Aarhus University Hospital Department of Biomedicine, Aarhus University, Aarhus, Denmark.

Background: Blood pressure (BP) control is important in chronic kidney disease (CKD), but a reduction in brachial BP may not mirror changes in central aortic BP (cBP) during antihypertensive medication. We hypothesize that a fall in cBP is better reflected during enhanced vasodilation treatment (EVT) compared with reduced vasodilation treatment (RVT) because of different hemodynamic actions of these interventions.

Methods: Eighty-one hypertensive CKD stage 3-4 patients (mean measured glomerular filtration rate 36 ml/min per 1. Read More

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Impact of Head-of-Bed Posture on Brain Oxygenation in Patients with Acute Brain Injury: A Prospective Cohort Study.

Neurocrit Care 2021 Jul 26. Epub 2021 Jul 26.

Department of Anesthesiology and Critical Care, Ramsay Santé Private Hospital De La Loire, Saint-Etienne, France.

Background: Therapeutic head positioning plays a role in the management of patients with acute brain injury. Although intracranial pressure (ICP) is typically lower in an upright posture than in a flat position, limited data exist concerning the effect of upright positioning on brain oxygenation and circulation. We sought to determine the impact of supine (0°) and semirecumbent (15° and 30°) postures on ICP, brain oxygenation, and brain circulation. Read More

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Peripheral microcirculatory abnormalities are associated with cardiovascular risk in systemic sclerosis: a nailfold video capillaroscopy study.

Clin Rheumatol 2021 Jul 27. Epub 2021 Jul 27.

Fourth Department of Internal Medicine, Hippokration Hospital, Aristotle University of Thessaloniki, Konstantinoupoleos Str. 49, Thessaloniki, Greece.

Introduction: Microvascular dysfunction is the key element in the pathogenesis of systemic sclerosis (SSc), whereas the contribution of large and medium size vessel abnormalities is yet to be established. The aim of the present study is to assess the association between micro- and macrovascular function by utilizing a broad spectrum of assessments of vascular performance.

Methods: We included consecutive, consenting SSc patients who underwent nailfold video capillaroscopy (NVC) for microcirculation evaluation. Read More

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Age-Related Changes in Centre of Pressure Trajectories Analysed with a Novel 'Return to Central' Analysis.

Authors:
Steven van Andel

J Mot Behav 2021 Jul 26:1-10. Epub 2021 Jul 26.

Department of Sport Science, University of Innsbruck, Innsbruck, Austria.

To evaluate age and fall-risk related changes in balance ability from measures of bipedal quiet stance, this study aims to investigate the characteristics of 'return to central' - Centre of Pressure (COP) trajectories. COP trajectories were extracted from 60-second COP recordings in bipedal stance. In anterior posterior direction, age was associated with a greater number of detected trajectories, increased velocity and more stringent control. Read More

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Active Brownian particle in homogeneous media of different viscosities: numerical simulations.

Phys Chem Chem Phys 2021 Jul 26. Epub 2021 Jul 26.

Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow, 125412, Russia.

Self-propelled colloids, active polymers and membranes, driven (vibrated) granular layers and hybrid synthetic-biological systems are striking examples of systems containing synthetic active Brownian particles. Such particles autonomously convert the available energy of the environment into their own directed mechanical motion. In most studies the self-propelled Brownian particles move in overdamped media. Read More

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Early-childhood BMI trajectories in relation to preclinical cardiovascular measurements in adolescence.

J Dev Orig Health Dis 2021 Jul 26:1-8. Epub 2021 Jul 26.

ISGlobal, Barcelona, Spain.

Cardiovascular diseases are the leading causes of morbidity and mortality. Overweight, obesity, and accelerated growth during early childhood have been associated with adverse cardiovascular outcomes in later life. Few studies have assessed whether trajectories of accelerated growth in early childhood are associated with preclinical cardiovascular measurements. Read More

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Sleep Apnea is Associated With Accelerated Vascular Aging: Results From 2 European Community-Based Cohort Studies.

J Am Heart Assoc 2021 Jul 26:e021318. Epub 2021 Jul 26.

INSERM UMR 970 Integrative Epidemiology of Cardiovascular Diseases University of Paris Paris France.

Background The mechanisms underlying the association between obstructive sleep apnea (OSA) and cardiovascular disease may include accelerated vascular aging. The aim was to compare the magnitude of vascular aging in patients with high versus low risk of OSA. Methods and Results In 2 community-based studies, the PPS3 (Paris Prospective Study 3) and the Maastricht Study, high risk of OSA was determined with the Berlin questionnaire (a screening questionnaire for OSA). Read More

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Cardiac, Macro-, and Micro-Circulatory Abnormalities in Association With Individual Metabolic Syndrome Component: The Northern Shanghai Study.

Front Cardiovasc Med 2021 9;8:690521. Epub 2021 Jul 9.

Department of Cardiology, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, China.

This study investigated the association of metabolic syndrome (MS) and its components with cardiac, macro-, and micro-circulatory abnormalities in an elderly Chinese population. This cross-sectional study was conducted using data for 1,958 participants from the Northern Shanghai Study aged over 65 years without a history of cardiovascular disease. MS was defined according to the National Cholesterol Education Program Adult Treatment Panel III in 2005 (NCEPIII 2005). Read More

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Exercise Training Duration and Intensity Are Associated With Thicker Carotid Intima-Media Thickness but Improved Arterial Elasticity in Active Children and Adolescents.

Front Cardiovasc Med 2021 8;8:618294. Epub 2021 Jul 8.

Institute of Preventive Pediatrics, TUM Department of Sport and Health Science, Technical University of Munich, Munich, Germany.

Even though exercise generally has a positive effect on health, intensive exercise can have adverse effects on the vascular system of adults. This study aimed to investigate the association between training duration and intensity and vascular structure and function in 427 physically active children and adolescents (14.0 ± 1. Read More

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[Changes of carotid artery elasticity before and after CPAP in patients with obstructive sleep apnea by ultrasonic ultrafast pulse wave velocity technique].

Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi 2021 Aug;35(8):707-711

Department of Ultrasound,the First Affiliated Hospital of Jinzhou Medical University,Jinzhou,121000,China.

To examine the changes of carotid artery elasticity in patients with obstructive sleep apnea(OSA) before and after continuous positive airway pressure(CPAP) treatment by ultrafast pulse wave velocity(UFPWV) technique,and to explore the influencing factors of carotid artery elasticity in OSA patients,and to provide guidance for clinical prevention and treatment of cardiovascular complications. Methods:Fifty cases of moderate and severe OSA patients diagnosed with PSG monitoring from January 2020 to December 2020 were collected as the OSA group,at the same time,40 healthy subjects who participated in physical examination and matched with OSA group in age and gender were selected as the control group.The OSA group was treated with CPAP for 12 weeks. Read More

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Investigation into cavitational intensity and COD reduction performance of the pinned disc reactor with various rotor-stator arrangements.

Ultrason Sonochem 2021 Jul 16;77:105669. Epub 2021 Jul 16.

Faculty of Mechanical Engineering, University of Ljubljana, Ljubljana, Slovenia. Electronic address:

In this study, the hydrodynamic cavitation and wastewater treatment performance of a rotary generator with pin disk for hydrodynamic cavitation are investigated. Various geometrical features and arrangements of rotor and stator pins were evaluated to improve the configuration of the cavitation device. The pilot device used to perform the experiments was upgraded with a transparent cover that allows visualization of the hydrodynamic cavitation in the rotor-stator region with high-speed camera and simultaneous measurement of pressure fluctuations. Read More

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Is there any relation between arterial stiffness and insomnia? A challenging question.

Sleep Breath 2021 Jul 24. Epub 2021 Jul 24.

Department of Psychiatry, University of Health Sciences Erenköy Mental Health and Neurological Diseases Training and Research Hospital, Istanbul, Turkey.

Purpose: Insomnia is a common sleep disorder which has high comorbidity with a number of cardiovascular diseases (CVD). As a possible risk factor for the CVDs, arterial stiffness may be assessed non-invasively by pulse wave velocity (PWV) and augmentation index (AI). The aim of this study was to evaluate any relation between insomnia and arterial stiffness. Read More

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Hydrodynamic model of blood flow in major arteries pulsing in various modes.

Med Biol Eng Comput 2021 Jul 24. Epub 2021 Jul 24.

Research Institute of Experimental Cardiology, 121552, Moscow, Russian Federation.

Traditionally, the arteries in mammals are viewed as the tubes with elastic wall, whose elasticity could be slowly (during a minute) tuned to change its diameter thereby regulating regional blood supply. Recent findings showed that an artery is a much more sophisticated organ, which can change elasticity of vascular wall within a fraction of a second during a cardiac cycle due to activation of its smooth muscles manifested by generation of arterial action potentials. The rapid variations in elasticity of vascular wall resulted in three basic modes of arterial pulsing: passive, active, and intermediate. Read More

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Scaling of axial muscle architecture in juvenile Alligator mississippiensis reveals an enhanced performance capacity of accessory breathing mechanisms.

J Anat 2021 Jul 23. Epub 2021 Jul 23.

Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.

Quantitative functional anatomy of amniote thoracic and abdominal regions is crucial to understanding constraints on and adaptations for facilitating simultaneous breathing and locomotion. Crocodilians have diverse locomotor modes and variable breathing mechanics facilitated by basal and derived (accessory) muscles. However, the inherent flexibility of these systems is not well studied, and the functional specialisation of the crocodilian trunk is yet to be investigated. Read More

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Repeating caldera collapse events constrain fault friction at the kilometer scale.

Proc Natl Acad Sci U S A 2021 Jul;118(30)

US Geological Survey, Volcano Science Center, Moffett Field, CA 94035.

Fault friction is central to understanding earthquakes, yet laboratory rock mechanics experiments are restricted to, at most, meter scale. Questions thus remain as to the applicability of measured frictional properties to faulting in situ. In particular, the slip-weakening distance [Formula: see text] strongly influences precursory slip during earthquake nucleation, but scales with fault roughness and is challenging to extrapolate to nature. Read More

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Ameliorative effect of allicin on vascular calcification via inhibiting endoplasmic reticulum stress.

Vascular 2021 Jul 23:17085381211035291. Epub 2021 Jul 23.

Geriatric Department, The Third Hospital of Hangzhou, Hangzhou, China.

Objectives: Vascular calcification (VC) is an independent predictor for cardiovascular events and mortality. However, there are currently no effective methods to reverse or prevent it. The present study aimed to determine the ameliorative effect of allicin on VC. Read More

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Nonlinear Dynamic Analysis of Axially Moving Laminated Shape Memory Alloy Beam with 1:3 Internal Resonance.

Materials (Basel) 2021 Jul 18;14(14). Epub 2021 Jul 18.

Laboratory of Test and Testing Technology, Tianjin Key Laboratory of Microgravity and Hypogravity Environment Simulation Technology, Tianjin 300384, China.

The remarkable properties of shape memory alloys (SMA) are attracting significant technological interest in many fields of science and engineering. In this paper, a nonlinear dynamic analytical model is developed for a laminated beam with a shape memory alloy layer. The model is derived based on Falk's polynomial model for SMAs combined with Timoshenko beam theory. Read More

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Flow Field Analysis Inside and at the Outlet of the Abrasive Head.

Materials (Basel) 2021 Jul 14;14(14). Epub 2021 Jul 14.

Department of Biological Instrumentation, Institute of Analytical Chemistry of the Czech Academy of Sciences, 60200 Brno, Czech Republic.

This paper focuses on the investigation of a multiphase flow of water, air, and abrasive particles inside and at the outlet of the abrasive head with the help of computational fluid dynamics calculations and measurements. A standard abrasive head with a water nozzle hole diameter of 0.33 mm (0. Read More

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Role of suction pressure in the stability of a gravity-driven thermoviscous liquid film flow down the interior surface of a cylinder.

Eur Phys J E Soft Matter 2021 Jul 22;44(7):100. Epub 2021 Jul 22.

Department of Chemical Engineering, Indian Institute of Technology Kanpur, Kanpur, 208016, India.

This study aims to analyze the stability of a gravity-driven thin film flow in the heated/cooled interior surface of a vertical hollow cylinder. The model development involves simplifying the flow and energy equations using the usual thin-film approximation, where the average film thickness is considered to be much smaller than the radius of cylinder. A dispersion relation is then derived to study the temporal stability of the system in order to quantify the effect of various non-dimensional parameters present in the model, such as the thermoviscous number, Marangoni number, Biot number, and Bond number. Read More

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Transcranial Doppler Based Cerebrovascular Reactivity Indices in Adult Traumatic Brain Injury: A Scoping Review of Associations With Patient Oriented Outcomes.

Front Pharmacol 2021 6;12:690921. Epub 2021 Jul 6.

Section of Neurosurgery, Department of Surgery, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada.

Disruption in cerebrovascular reactivity following traumatic brain injury (TBI) is a known phenomenon that may hold prognostic value and clinical relevance. Ultimately, improved knowledge of this process and more robust means of continuous assessment may lead to advances in precision medicine following TBI. One such method is transcranial Doppler (TCD), which has been employed to evaluate cerebrovascular reactivity following injury utilizing a continuous time-series approach. Read More

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Improvement of exhausted cerebral autoregulation in patients with idiopathic intracranial hypertension benefit of venous sinus stenting.

Physiol Meas 2021 Jul 22. Epub 2021 Jul 22.

Neurology, Beijing Tiantan Hospital, Beijing, CHINA.

Objective: Utilizing transfer function analysis to assess the cerebral autoregulation in patients with idiopathic intracranial hypertension (IIH), and to explore its improvement after venous sinus stenting.

Approach: In total, 15 consecutive IIH patients with venous sinus stenosis and 15 controls were recruited. All the patients underwent digital subtraction angiography and venous manometry. Read More

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Remediation of contaminated dredged harbor sediments by combining hydrodynamic cavitation, hydrocyclone, and persulfate oxidation process.

J Hazard Mater 2021 Jul 6;420:126594. Epub 2021 Jul 6.

Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan. Electronic address:

A pilot-scale hybrid treatment system consisting of hydrodynamic cavitation (HC), hydrocyclone separator (HS), and sodium persulfate (PS), was employed for removing polycyclic aromatic hydrocarbons (PAHs) from dredged harbor sediments. The effectiveness of PAH degradation was studied by varying the inlet pressure (0-2.0 bar), PS dosage (or Σ[PAH] to [PS] mole ratio of 1:1-1:10) at HS inflow velocity of 2. Read More

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Personalized 0D-1D multiscale hemodynamic modeling and wave dynamics analysis of cerebral circulation for an elderly patient with dementia.

Int J Numer Method Biomed Eng 2021 Jul 22:e3510. Epub 2021 Jul 22.

Graduate School of Engineering, Chiba University, Chiba, Japan.

Senile dementia is associated with pronounced alterations in cerebral circulation. A fundamental understanding of intracranial hemodynamics and wave dynamics is essential for assessing dementia risk. Recent findings suggest that higher carotid artery wave intensity (WI) can predict future cognitive impairments in the elderly. Read More

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Effects of diaphragmatic control on multiparametric analysis of the sniff nasal inspiratory pressure test and inspiratory muscle activity in healthy subjects.

PLoS One 2021 22;16(7):e0253132. Epub 2021 Jul 22.

PneumoCardioVascular Lab/HUOL, Hospital Universitário Onofre Lopes, Empresa Brasileira de Serviços Hospitalares and Departamento de Fisioterapia Universidade Federal do Rio Grande do Norte, Natal, Brazil.

Background: We investigated the influence of diaphragmatic activation control (diaphC) on the relaxation rate, contractile properties and electrical activity of the inspiratory muscles of healthy subjects. Assessments were performed non-invasively using the sniff inspiratory pressure test (SNIP) and surface electromyography, respectively.

Methods: Twenty-two subjects (10 men and 12 women) performed 10 sniff maneuvers in two different days: with and without diaphC instructions. Read More

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Low-Power Laser Ignition of an Antenna-Type Secondary Energetic Copper Complex: Synthesis, Characterization, Evaluation, and Ignition Mechanism Studies.

Inorg Chem 2021 Jul 22. Epub 2021 Jul 22.

Department of Chemistry, Ludwig Maximilian University Munich, München 81377, Germany.

In recent years, development of new energetic compounds and formulations, suitable for ignition with relatively low-power lasers, is a highly active and competitive field of research. The main goal of these efforts is focused on achieving and providing much safer solutions for various detonator and initiator systems. In this work, we prepared, characterized, and studied thermal and ignition properties of a new laser-ignitable compound, based on the 5,6-bis(ethylnitroamino)-'2,'3-dihydroxypyrazine-2,3-bis(carboximidamide) (DS3) proligand. Read More

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Ophthalmic artery Doppler in the prediction of preeclampsia.

Am J Obstet Gynecol 2021 Jan 8. Epub 2021 Jan 8.

Institute of Health Research, College of Medicine and Health, University of Exeter, Exeter, United Kingdom.

The ophthalmic artery is an easily accessible vessel for Doppler assessment that provides information on the less accessible intracranial circulation. In women with preeclampsia, compared with normotensive pregnant women, there is a decrease in impedance to flow and an increase in velocities in the flow velocity waveforms from the ophthalmic arteries. This study aimed to report the methodology for ophthalmic artery Doppler and summarize findings from the clinical implementation of such assessment in the prediction of preeclampsia. Read More

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January 2021

Changes in AZGP1 Serum Levels and Correlation With Pulse Wave Velocity After Kidney Transplantation.

Front Cardiovasc Med 2021 5;8:692213. Epub 2021 Jul 5.

Department of Nephrology and Hypertension, Hannover Medical School, Hanover, Germany.

Zinc-alpha 2-glycoprotein (AZGP1), a secreted protein with ubiquitous tissue expression, has been controversially linked to the risk of cardiovascular disease. In a cohort of kidney transplant recipients, we measured serum AZGP1 levels after transplantation over a 2 year period and tested for an association with pulse wave velocity as an important parameter indicating future cardiovascular events. Annual blood sampling and pulse wave velocity measurements were longitudinally performed in 113 kidney transplant recipients. Read More

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Understanding of remora's "hitchhiking" behaviour from a hydrodynamic point of view.

Sci Rep 2021 Jul 21;11(1):14837. Epub 2021 Jul 21.

Department of Naval Architecture, Ocean & Marine Engineering, University of Strathclyde, Henry Dyer Building, 100 Montrose Street, Glasgow, G4 0LZ, UK.

Symbiotic relationships have developed through natural evolution. For example, that of the remora fish attached to the body of a shark. From the remora's perspective, this could be associated to an increased hydrodynamic efficiency in swimming and this needs to be investigated. Read More

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