42,621 results match your criteria high velocity


Kinematics and Esthetics of Grand Battement After Static and Dynamic Hamstrings Stretching in Adolescents.

Motor Control 2021 Apr 9:1-20. Epub 2021 Apr 9.

University of Antwerp.

The objective of this study was to explore the effects of static and dynamic hamstring muscles stretching on kinematics and esthetics of grand battement (high velocity kicks) in adolescent recreational dancers. Sixteen participants were assessed before and immediately after both stretching modalities. Kinematics of movement was measured by an optoelectronic system and esthetics was scored by a jury of professional dancers. Read More

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Blood volume flow in the superficial temporal artery assessed by duplex sonography: predicting extracranial-intracranial bypass patency in moyamoya disease.

J Neurosurg 2021 Apr 9:1-8. Epub 2021 Apr 9.

Departments of1Neurology and.

Objective: Superficial temporal artery-middle cerebral artery (STA-MCA) bypass surgery is an important therapy for symptomatic moyamoya disease. Its success depends on bypass function, which may be impaired by primary or secondary bypass insufficiency. Catheter angiography is the current gold standard to assess bypass function, whereas the diagnostic value of ultrasonography (US) has not been systematically analyzed so far. Read More

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Quantifying the spatiotemporal influence of acute myocardial ischemia on volumetric conduction velocity.

J Electrocardiol 2021 Mar 23;66:86-94. Epub 2021 Mar 23.

Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT, USA; Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, USA; Nora Eccles Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, UT, USA.

Introduction: Acute myocardial ischemia occurs when coronary perfusion to the heart is inadequate, which can perturb the highly organized electrical activation of the heart and can result in adverse cardiac events including sudden cardiac death. Ischemia is known to influence the ST and repolarization phases of the ECG, but it also has a marked effect on propagation (QRS); however, studies investigating propagation during ischemia have been limited.

Methods: We estimated conduction velocity (CV) and ischemic stress prior to and throughout 20 episodes of experimentally induced ischemia in order to quantify the progression and correlation of volumetric conduction changes during ischemia. Read More

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Effects of low vs. high frequency local vibration on mild-moderate muscle spasticity: Ultrasonographical and functional evaluation in patients with multiple sclerosis.

Mult Scler Relat Disord 2021 Mar 31;51:102930. Epub 2021 Mar 31.

Hacettepe University, Faculty of Physical Therapy and Rehabilitation, 06100 Samanpazarı/Altındag, Ankara, Turkey. Electronic address:

Background: Local vibration (LV) is a physiotherapy application that aims to reduce spasticity. The study aimed to compare the effects of 50 Hz vs. 100 Hz LV on mild-moderate spasticity, functional performance and muscle architecture. Read More

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REDASA: A Secure Continually Updating Web-Source Processing Pipeline supporting a REaltime DAta Synthesis and Analysis of Scientific Literature.

J Med Internet Res 2021 Apr 3. Epub 2021 Apr 3.

PanSurg Collaborative, Department of Surgery and Cancer, Imperial College London, London, GB.

Background: The scale and quality of the global scientific response to the COVID-19 pandemic has unquestionably saved lives. However, COVID-19 has also triggered an unprecedented "infodemic"; the velocity and volume of data production has overwhelmed many key stakeholders such as clinicians and policymakers who have been unable to process structured and unstructured data for evidence-based decision making. Current solutions which aim to alleviate this data synthesis challenge are unable to capture heterogeneous web data in "real-time" for the production of concomitant answers and are not based on the high-quality information in response to a free-text query. Read More

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Phononics of Graphene Interfaced with Flowing Ionic Fluid: An Avenue for High Spatial Resolution Flow Sensor Applications.

ACS Nano 2021 Apr 9. Epub 2021 Apr 9.

Department of Chemical Engineering, University of Illinois at Chicago, Chicago, Illinois 60607, United States.

While ionic flow over graphenic structures creates electromotive potential, there is a need to understand the local carrier density induced in graphene without any electrode-induced Fermi-level pinning. Here, we show the electrolyte-flow induced localized doping in graphene inspecting its Raman phononic energy. Graphene's Fermi energy level has a logarithmic dependence to the flow velocity over 2 orders of magnitude of velocity (∼100 μm s to 10 mm s). Read More

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Is superficial radial nerve affected in patients with hand osteoarthritis?

J Hand Ther 2021 Jan 12. Epub 2021 Jan 12.

Department of Physical Medicine and Rehabilitation, Ankara Dışkapı Yıdırım Beyazıt Training and Research Hospital, University of Health Sciences Turkey, Ankara, Turkey.

Introduction: Patients with superficial radial neuropathy (SRN) have pain and abnormal sensation on the hand similar to hand osteoarthritis (HOA).

Purpose Of The Study: The aim of the present study was to evaluate the presence of SRN in patients with HOA and to determine the factors associated with electrophysiological parameters of the radial nerve.

Study Design: This is a case-control study. Read More

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January 2021

Maximal kinetic energy and angular distribution analysis of spatial map imaging: Application to photoelectrons from a single quantum state of HO.

J Chem Phys 2021 Apr;154(13):134201

Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 8410501, Israel.

Dynamical or spatial properties of charged species can be obtained using electrostatic lenses by velocity map imaging (VMI) or spatial map imaging (SMI), respectively. Here, we report an approach for extracting dynamical and spatial information from patterns in SMI images that map the initial coordinates, velocity vectors, and angular distributions of charged particles onto the detector, using the same apparatus as in VMI. Deciphering these patterns required analysis and modeling, involving both their predictions from convolved spatial and velocity distributions and fitting observed images to kinetic energies (KEs) and anisotropy parameters (βs). Read More

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Bonding few-layered graphene via collision with high-speed fullerenes.

Nanotechnology 2021 Apr 8. Epub 2021 Apr 8.

Department of Engineering, Shenzhen MSU-BIT University, Shenzhen, Guangdong, CHINA.

Graphene, as a typical two-dimensional material, is popular in the design of nanodevices. The interlayer relative sliding of graphene sheets can significantly affect the effective bending stiffness of the few-layered graphene. For restricting the relative sliding, we adopted the atomic shot peening method to bond the graphene sheets together by ballistic C60 fullerenes from its two surfaces. Read More

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Toward Exotic Silicon Doping with a Low Thermal Budget and Flexible Profile Control by Liquid-Phase Epitaxy.

ACS Appl Mater Interfaces 2021 Apr 8. Epub 2021 Apr 8.

Department of Nanoengineering, University of California San Diego, La Jolla, California 92093, United States.

We investigate semiconductor p-n junction formation by liquid-phase epitaxy (LPE) using metallic pastes incorporating traditional and nontraditional dopants. The LPE technique enables us to control the shape of doping profiles with a low thermal budget through the choice of solvent, total amount of solvent deposited, and process temperature. We focus here on the Al-B, Zn-P, and Sn-Ga chemistries to dope silicon regions using the chemicophysical properties of a low-eutectic-temperature metallic solvent acting as a matrix for the dissolution of a high concentration of a dopant. Read More

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Differential proteins associated with plasma membrane in X- and/or Y-chromosome bearing spermatozoa in indicus cattle.

Reprod Domest Anim 2021 Apr 7. Epub 2021 Apr 7.

ICAR-Indian Institute of Agricultural Biotechnology, Ranchi, India.

The differential proteins associated with plasma membrane of spermatozoa are less known, identification of which shall help overcome limitations of currently used methods of sperm sexing, considered as a high priority for livestock sector of many countries. This study has reported plasma membrane proteomics of unsorted spermatozoa and differential expression of plasma membrane associated proteins between X- and Y- chromosome bearing spermatozoa of indicus cattle (Bos indicus). Isolation of plasma membrane fraction using percoll gradient, relatively a rapid method, from bovine spermatozoa has been reported to enrich isolation of plasma membrane proteins. Read More

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Analysis of Turbulence Effects in a Patient-Specific Aorta with Aortic Valve Stenosis.

Cardiovasc Eng Technol 2021 Apr 7. Epub 2021 Apr 7.

Department of Chemical Engineering, Imperial College London, South Kensington Campus, London, SW7 2AZ, UK.

Blood flow in the aorta is often assumed laminar, however aortic valve pathologies may induce transition to turbulence and our understanding of turbulence effects is incomplete. The aim of the study was to provide a detailed analysis of turbulence effects in aortic valve stenosis (AVS).

Methods: Large-eddy simulation (LES) of flow through a patient-specific aorta with AVS was conducted. Read More

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Applicability of High-Frequency Ultrasound to the Early Diagnosis of Diabetic Peripheral Neuropathy.

Biomed Res Int 2021 18;2021:5529063. Epub 2021 Mar 18.

Department of Ultrasound, Qingdao Municipal Hospital, Qingdao, Shandong 266071, China.

This study investigated the applicability of high-frequency ultrasound (HFU) to the early diagnosis of diabetic peripheral neuropathy (DPN). Patients with type 2 diabetes ( = 60) were divided into diabetic nonperipheral neuropathy and DPN groups (group A and group B, respectively; = 30 each) based on electroneurophysiologic findings. Additionally, 30 nondiabetic patients were included as the healthy control group (group C). Read More

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Feasibility of Doppler Ultrasound for Cortical Cerebral Blood Flow Velocity Monitoring During Major Non-cardiac Surgery of Newborns.

Front Pediatr 2021 22;9:656806. Epub 2021 Mar 22.

Department of Anaesthesiology, Erasmus MC University Medical Centre, Rotterdam, Netherlands.

Newborns needing major surgical intervention are at risk of brain injury and impaired neurodevelopment later in life. Disturbance of cerebral perfusion might be an underlying factor. This study investigates the feasibility of serial transfontanellar ultrasound measurements of the pial arteries during neonatal surgery, and whether perioperative changes in cerebral perfusion can be observed and related to changes in the perioperative management. Read More

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Motion tracking of iris features to detect small eye movements.

J Eye Mov Res 2019 Apr 5;12(6). Epub 2019 Apr 5.

Carlson Center for Imaging Science, Rochester Institute of Technology, NY, USA.

The inability of current video-based eye trackers to reliably detect very small eye movements has led to confusion about the prevalence or even the existence of monocular microsaccades (small, rapid eye movements that occur in only one eye at a time). As current methods often rely on precisely localizing the pupil and/or corneal reflection on successive frames, current microsaccade-detection algorithms often suffer from signal artifacts and a low signal-to-noise ratio. We describe a new video-based eye tracking methodology which can reliably detect small eye movements over 0. Read More

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Increased microsaccade rate in individuals with ADHD traits.

J Eye Mov Res 2017 Mar 4;10(1). Epub 2017 Mar 4.

Staffordshire University, Stoke-on-Trent, UK.

Microsaccades are involuntary, small, jerk-like eye-movements with high-velocity that are observed during fixation. Abnormal microsaccade rates and characteristics have been observed in a number of psychiatric and developmental disorders. In this study, we examine microsaccade differences in 43 non-clinical participants with high and low levels of ADHDlike traits, assessed with the Adult ADHD Self-Report Scale [28]. Read More

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Binary coagulation system (graphene oxide/chitosan) for polluted surface water treatment.

J Environ Manage 2021 Mar 31;288:112481. Epub 2021 Mar 31.

Chemistry Department, Faculty of Science, Tanta University, Tanta, 31527, Egypt; Misr University for Science and Technology (MUST), 6th of October City, Egypt.

In this study, chitosan (CS) is used as a natural coagulant aid alongside graphene oxide (GO) to remove turbidity and numerous pollutants from raw and artificially contaminated surface water. The coagulation capability of the system (GO/CS) was assessed with respect to a water sample's turbidity, pH, coagulant dose, settling velocity, and temperature. The presence of CS enhanced the coagulation capacity of GO at varied pH levels and no GO residue was detected in the water after the treatment. Read More

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Gamma radiation negatively impacted seed germination, seedling growth and antioxidant enzymes activities in tall fescue infected with Epichloë endophyte.

Ecotoxicol Environ Saf 2021 Apr 4;216:112169. Epub 2021 Apr 4.

Nuclear Agriculture Research School, Nuclear Science and Technology Research Institute, Karaj, Iran.

Plants and their accompanying microorganisms growing in contaminated sites with long-lived gamma-emitting radionuclides may be affected by radiation stress. The present study aimed to investigate the effects of gamma radiation on symbiotic relationship between Epichloë endophyte and Festuca arundinacea plant along with the radio-sensitivity of a pair of clones of tall fescue with (E+) and without (E-) symbiotic Epichloë endophyte exposed to different doses of gamma radiation including 25, 50, 75, 100, 150, 200, 300, and 400 Gray (Gy) from a Cobalt-60 source. Both irradiated and non-irradiated seeds of each status were grown under controlled conditions. Read More

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Atomically Dispersed Y or La on Birnessite-Type MnO for the Catalytic Decomposition of Low-Concentration Toluene at Room Temperature.

ACS Appl Mater Interfaces 2021 Apr 7. Epub 2021 Apr 7.

State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.

Room-temperature catalytic decomposition of low-concentration volatile organic compounds (VOCs) in indoor air is an exciting dream to solve their pollution. Herein, two kinds of rare-earth elements (Y and La) were separately doped into birnessite-type MnO nanosheets in the form of single atoms by the hydrothermal method. As-synthesized La/MnO achieved 100% removal of 10 ppm toluene at 40 °C under the gas hourly space velocity of 60 L g h, which was even somewhat better than the single Pt atom-doped MnO. Read More

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Computational fluid dynamics of the airways after left-upper pulmonary lobectomy: a case study.

Int J Numer Method Biomed Eng 2021 Apr 7:e3462. Epub 2021 Apr 7.

Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Italy.

Pulmonary lobectomy is the gold standard intervention for lung cancer removal and consists in the complete resection of the affected lung lobe, which, coupled with the re-adaptation of the remaining thoracic structures, decreases the postoperative pulmonary function of the patient. Current clinical practice, based on spirometry and cardiopulmonary exercise tests, does not consider local changes, providing an average at-the-mouth estimation of residual functionality. Computational Fluid Dynamics (CFD) has proved a valuable solution to obtain quantitative and local information about airways airflow dynamics. Read More

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Programming Interval Training to Optimize Time-Trial Performance: A Systematic Review and Meta-Analysis.

Sports Med 2021 Apr 7. Epub 2021 Apr 7.

Department of Exercise Science, Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada.

Background: Interval training has become an essential component of endurance training programs because it can facilitate a substantial improvement in endurance sport performance. Two forms of interval training that are commonly used to improve endurance sport performance are high-intensity interval training (HIIT) and sprint interval training (SIT). Despite extensive research, there is no consensus concerning the optimal method to manipulate the interval training programming variables to maximize endurance performance for differing individuals. Read More

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The Effects of Type 1 Diabetes and Diabetic Peripheral Neuropathy on the Musculoskeletal System: A Case-Control Study.

J Bone Miner Res 2021 Apr 6. Epub 2021 Apr 6.

Academic Unit of Bone Metabolism, University of Sheffield, Sheffield, UK.

Fracture risk is increased in type 1 diabetes (T1D). Diabetic neuropathy might contribute to this increased risk directly through effects on bone turnover and indirectly through effects on balance, muscle strength, and gait. We compared patients with T1D with (T1DN+, n = 20) and without (T1DN-, n = 20) distal symmetric sensorimotor polyneuropathy and controls (n = 20). Read More

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Traumatic aortic injury: Computed tomography angiography imaging and findings revisited in patients surviving major thoracic aorta injuries.

SA J Radiol 2021 12;25(1):2044. Epub 2021 Mar 12.

Department of Diagnostic Radiology and Imaging, Faculty of Radiology, University of Pretoria, Pretoria, South Africa.

Blunt chest trauma related acute thoracic aortic injury (TAI) is a life-threatening condition that requires prompt diagnosis and appropriate management because of high mortality. Computed tomography angiography (CTA) is the imaging of choice for evaluation of patients with major chest trauma findings suspicious of TAI on chest radiography. This case series describes the CTA findings in four high-velocity incident survivors with associated TAIs, discusses the injury type and treatment, and reviews the literature. Read More

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Diet quality trajectories and cardiovascular phenotypes/metabolic syndrome risk by 11-12 years.

Int J Obes (Lond) 2021 Apr 6. Epub 2021 Apr 6.

Murdoch Children's Research Institute, Parkville, VIC, Australia.

Objective: To investigate associations between early-life diet trajectories and preclinical cardiovascular phenotypes and metabolic risk by age 12 years.

Methods: Participants were 1861 children (51% male) from the Longitudinal Study of Australian Children. At five biennial waves from 2-3 to 10-11 years: Every 2 years from 2006 to 2014, diet quality scores were collected from brief 24-h parent/self-reported dietary recalls and then classified using group-based trajectory modeling as 'never healthy' (7%), 'becoming less healthy' (17%), 'moderately healthy' (21%), and 'always healthy' (56%). Read More

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Development and validation of a novel prediction score for cardiac tamponade in emergency department patients with pericardial effusion.

Eur Heart J Acute Cardiovasc Care 2020 Nov 7. Epub 2020 Nov 7.

Department of Medicine, Cardiovascular Division, Brigham and Women's Hospital, 75 Francis Street, Boston, MA 02115, USA.

Aims: Determining which patients with pericardial effusion require urgent intervention can be challenging. We sought to develop a novel, simple risk prediction score for patients with pericardial effusion.

Methods And Results: Adult patients admitted through the emergency department (ED) with pericardial effusion were retrospectively evaluated. Read More

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November 2020

Developing a standardized curriculum for teaching chiropractic technique.

J Chiropr Educ 2021 Apr 5. Epub 2021 Apr 5.

Objective: This is a report of the results of 4 facilitated workshops aimed at developing a standardized chiropractic technique curriculum.

Methods: Workshops were held at research conferences during 2014, 2016, 2018, and 2019. Participants were tasked with developing recommendations for diagnostic and therapeutic procedures appropriate for chiropractic technique programs. Read More

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Mitigation of phase noise and Doppler-induced frequency offsets in coherent random amplitude modulated continuous-wave LiDAR.

Opt Express 2021 Mar;29(6):9060-9083

We present a detailed analysis of techniques to mitigate the effects of phase noise and Doppler-induced frequency offsets in coherent random amplitude modulated continuous-wave (RAMCW) LiDAR. The analysis focuses specifically on a technique which uses coherent dual-quadrature detection to enable a sum of squares calculation to remove the input signal's dependence on carrier phase and frequency. This increases the correlation bandwidth of the matched-template filter to the bandwidth of the acquisition system, whilst also supporting the simultaneous measurement of relative radial velocity with unambiguous direction-of-travel. Read More

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Ultra-brilliant GeV betatronlike radiation from energetic electrons oscillating in frequency-downshifted laser pulses.

Opt Express 2021 Mar;29(6):8926-8940

Electrons can be accelerated to GeV energies with high collimation via laser wakefield acceleration in the bubble regime and emit bright betatron radiation in a table-top size. However, the radiation brightness is usually limited to the third-generation synchrotron radiation facilities operating at similar photon energies. Using a two-stage plasma configuration, we propose a novel scheme for generating betatronlike radiation with an extremely high brilliance. Read More

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Particle velocity measurement within a free-falling particle curtain using microscopic shadow velocimetry.

Opt Express 2021 Mar;29(7):10923-10938

We report an optical method for particle velocity measurement that is suitable for the measurement of particle velocities within dense particle-laden flows with high spatial resolution. The technique is based on particle shadow velocimetry with the use of a long-distance microscopic lens for images collection. The narrow depth of field of the lens allows particles within the focal plane to have much higher pattern intensities than those outside it on the collected images. Read More

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Collective optical Thomson scattering in pulsed-power driven high energy density physics experiments (invited).

Rev Sci Instrum 2021 Mar;92(3):033542

Blackett Laboratory, Imperial College, London SW7 2BW, United Kingdom.

Optical collective Thomson scattering (TS) is used to diagnose magnetized high energy density physics experiments at the Magpie pulsed-power generator at Imperial College London. The system uses an amplified pulse from the second harmonic of a Nd:YAG laser (3 J, 8 ns, 532 nm) to probe a wide diversity of high-temperature plasma objects, with densities in the range of 10-10 cm and temperatures between 10 eV and a few keV. The scattered light is collected from 100 μm-scale volumes within the plasmas, which are imaged onto optical fiber arrays. Read More

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