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https://www.readbyqxmd.com/read/29148155/identifying-biomechanical-gait-parameters-in-adolescent-boys-with-haemophilia-using-principal-component-analysis
#1
L B Suckling, D Stephensen, M C Cramp, R Mahaffey, W I Drechsler
INTRODUCTION: Improvements in the medical management for those with haemophilia have resulted in improved clinical outcomes. However, current treatment regimens do not alleviate all joint haemarthroses with the potential for long-term joint deterioration remaining. The evaluation of functional activities such as gait, using standardized tools to monitor children with haemophilia is emerging. AIM: This study explored differences in sagittal plane biomechanics of walking in adolescent boys aged 11-18 years with haemophilia and an age-matched group of typically developing boys...
November 17, 2017: Haemophilia: the Official Journal of the World Federation of Hemophilia
https://www.readbyqxmd.com/read/29142324/an-algorithm-for-the-beat-to-beat-assessment-of-cardiac-mechanics-during-sleep-on-earth-and-in-microgravity-from-the-seismocardiogram
#2
Marco Di Rienzo, Emanuele Vaini, Prospero Lombardi
Seismocardiogram, SCG, is the measure of precordial vibrations produced by the beating heart, from which cardiac mechanics may be explored on a beat-to-beat basis. We recently collected a large amount of SCG data (>69 recording hours) from an astronaut to investigate cardiac mechanics during sleep aboard the International Space Station and on Earth. SCG sleep recordings are characterized by a prolonged duration and wide heart rate swings, thus a specific algorithm was developed for their analysis. In this article we describe the new algorithm and its performance...
November 15, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29133229/use-of-electrical-penetration-graphs-epg-and-quantitative-pcr-to-evaluate-the-relationship-between-feeding-behaviour-and-pandora-neoaphidis-infection-levels-in-green-peach-aphid-myzus-persicae
#3
Chun Chen, Sudan Ye, Huajun Hu, Chengmei Xue, Xiaoping Yu
A real-time qPCR method was developed, validated, and used to quantity the fungal pathogen, P. neoaphidis, within aphids at different times during infection; colonization rate fitted the Gompertz model well (R(b)=0.9356). Feeding behaviour of P. neoaphidis-infected and uninfected M. persicae were investigated, for the first time, using DC-electrical penetration graphs (DC-EPG) that characterized the waveforms made during different aphid stylet probing periods corresponding to epidermis penetration, salivation and ingestion...
November 10, 2017: Journal of Insect Physiology
https://www.readbyqxmd.com/read/29122445/a-method-for-the-topographical-identification-and-quantification-of-high-frequency-oscillations-in-intracranial-electroencephalography-recordings
#4
Zachary J Waldman, Shoichi Shimamoto, Inkyung Song, Iren Orosz, Anatol Bragin, Itzhak Fried, Jerome Engel, Richard Staba, Michael R Sperling, Shennan A Weiss
OBJECTIVE: To develop a reliable software method using a topographic analysis of time-frequency plots to distinguish ripple (80-200 Hz) oscillations that are often associated with EEG sharp waves or spikes (RonS) from sinusoid-like waveforms that appear as ripples but correspond with digital filtering of sharp transients contained in the wide bandwidth EEG. METHODS: A custom algorithm distinguished true from false ripples in one second intracranial EEG (iEEG) recordings using wavelet convolution, identifying contours of isopower, and categorizing these contours into sets of open or closed loop groups...
October 21, 2017: Clinical Neurophysiology: Official Journal of the International Federation of Clinical Neurophysiology
https://www.readbyqxmd.com/read/29096216/rhythmic-eeg-patterns-in-extremely-preterm-infants-classification-and-association-with-brain-injury-and-outcome
#5
Lauren C Weeke, Inge M van Ooijen, Floris Groenendaal, Alexander C van Huffelen, Ingrid C van Haastert, Carolien van Stam, Manon J Benders, Mona C Toet, Lena Hellström-Westas, Linda S de Vries
OBJECTIVE: Classify rhythmic EEG patterns in extremely preterm infants and relate these to brain injury and outcome. METHODS: Retrospective analysis of 77 infants born <28 weeks gestational age (GA) who had a 2-channel EEG during the first 72 h after birth. Patterns detected by the BrainZ seizure detection algorithm were categorized: ictal discharges, periodic epileptiform discharges (PEDs) and other waveforms. Brain injury was assessed with sequential cranial ultrasound (cUS) and MRI at term-equivalent age...
October 3, 2017: Clinical Neurophysiology: Official Journal of the International Federation of Clinical Neurophysiology
https://www.readbyqxmd.com/read/29092616/infrasound-propagation-in-tropospheric-ducts-and-acoustic-shadow-zones
#6
Catherine D de Groot-Hedlin
Numerical computations of the Navier-Stokes equations governing acoustic propagation are performed to investigate infrasound propagation in the troposphere and into acoustic shadow zones. An existing nonlinear finite-difference, time-domain (FDTD) solver that constrains input sound speed models to be axisymmetric is expanded to allow for advection and rigid, stair-step topography. The FDTD solver permits realistic computations along a given azimuth. It is applied to several environmental models to examine the effects of nonlinearity, topography, advection, and two-dimensional (2D) variations in wind and sound speeds on the penetration of infrasound into shadow zones...
October 2017: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/29060705/cardiac-safety-profile-for-random-complex-waveforms
#7
Hugh Pratt, Christopher Andrews, Dorin Panescu, Blossom Lake
INTRODUCTION: A rigorous method for assessing the Ventricular Fibrillation (VF) risk of a Random Complex Waveform (RCW) has not been previously available. Real-life hazardous events motivated us to develop such method. An RCW is observable and recordable. It consists of multiple different components randomly added one to the other. Assessment for VF risk exists for non-random waveforms, particularly VF thresholds for 50/60 Hz alternating currents, but not for RCWs. METHODS: We developed a method which considers exposure to a segment of an RCW...
July 2017: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/29060331/new-conducted-electrical-weapons-thoracic-cage-shielding-effects
#8
Dorin Panescu, Mark W Kroll, Michael A Brave
INTRODUCTION: The TASER(®) conducted electrical weapon (CEW) delivers electrical pulses that can temporarily incapacitate subjects. For existing CEW models, we have previously presented the distribution of currents in tissues posterior to the sternum and their likelihood of triggering cardiac arrhythmias. New models, the eXperimental Rotating-Field (XRF) waveform CEW (in development) and the X2 CEW (released) have not been investigated. Both the XRF and X2 CEWs target a precise amount of delivered charge per pulse, 64 μC and 62 μC, respectively...
July 2017: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/29053767/characterizing-and-comparing-the-seasonality-of-influenza-like-illnesses-and-invasive-pneumococcal-diseases-using-seasonal-waveforms
#9
Matthieu Domenech de Cellès, Hélène Arduin, Emmanuelle Varon, Cécile Souty, Pierre-Yves Boëlle, Daniel Lévy-Bruhl, Sylvie van der Werf, Jean-Claude Soulary, Didier Guillemot, Laurence Watier, Lulla Opatowski
The seasonalities of influenza-like illnesses (ILIs) and invasive pneumococcal diseases (IPDs) remain incompletely understood. Experimental evidence indicates that influenza-virus infection predisposes to pneumococcal disease, so that a correspondence in the seasonal patterns of ILIs and IPDs might exist at the population level. We developed a method to characterize seasonality by means of easily interpretable summary statistics of seasonal shape-or seasonal waveforms. Non-linear mixed-effects models were used to estimate those waveforms based on weekly case reports of ILIs and IPDs in five regions spanning continental France from July 2000 to June 2014...
October 19, 2017: American Journal of Epidemiology
https://www.readbyqxmd.com/read/29045640/action-potential-contour-contributes-to-species-differences-in-repolarization-response-to-%C3%AE-adrenergic-stimulation
#10
Luca Sala, Bence Hegyi, Chiara Bartolucci, Claudia Altomare, Marcella Rocchetti, Krisztina Váczi, Gaspare Mostacciuolo, Norbert Szentandrássy, Stefano Severi, Péter Pál Nánási, Antonio Zaza
Aim: Repolarization response to β-adrenergic (β-AR) stimulation differs between guinea-pig and canine myocytes and, within the latter, between myocardial layers. Correlative analysis suggests that this may be due to differences in action potential (AP) contour. Here we tested whether AP contour may set the response of current and of repolarization to β-AR stimulation (10 nM isoproterenol, ISO). Methods and Results: The responses of AP and current to ISO were measured under I-clamp and "AP-clamp" in guinea-pig (GP), dog epicardial (DEPI) and dog subendocardial (DENDO) myocytes...
October 17, 2017: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
https://www.readbyqxmd.com/read/29033283/developmental-trajectory-of-mismatch-negativity-and-visual-event-related-potentials-in-healthy-controls-implications-for-neurodevelopmental-vs-neurodegenerative-models-of-schizophrenia
#11
Cheryl M Corcoran, Anastasia Stoops, Migyung Lee, Antigona Martinez, Pejman Sehatpour, Elisa C Dias, Daniel C Javitt
Sensory processing deficits are core features of schizophrenia, reflected in impaired generation of event-related potential (ERP) measures such as auditory mismatch negativity (MMN) and visual P1. To understand the potential time course of development of deficits in schizophrenia, we obtained MMN to unattended duration, intensity and frequency deviants, and visual P1 to attended LSF stimuli, in 43 healthy individuals ages 6 to 25years (mean 17), and compared results to data from 30 adult schizophrenia patients (mean age 38)...
October 12, 2017: Schizophrenia Research
https://www.readbyqxmd.com/read/28994160/the-use-of-accelerometer-to-measure-sleeping-posture-of-beef-cows
#12
Michiru Fukasawa, Tokushi Komatsu, Yumi Higashiyama, Akinori Oshibe
Sleep is one of the essential behaviors for mammals. The aims of this study were to validate the use of accelerometer for measuring sleeping posture of cattle. Duration of sleeping posture of seven Japanese Black cows from 19.00 to 07.00 hours was measured by both accelerometer and video, and a total of 67 accelerometer and video measurement sets were collected. We calculated Cohen's κ coefficient between accelerometer and video measurements and 91.5% of the κ-values were >0.80. Intra- and inter-observer coefficient of variance showed that specific acceleration waveform patterns of sleeping posture could be easily and accurately detected by independent observers...
October 9, 2017: Animal Science Journal, Nihon Chikusan Gakkaihō
https://www.readbyqxmd.com/read/28993442/in-room-assessment-of-intravascular-velocity-from-time-resolved-rotational-angiography-in-patients-with-arteriovenous-malformation-a-pilot-study
#13
Chung Jung Lin, Huai Che Yang, Ai Chi Chien, Wan Yuo Guo, Chih Chun Wu, Sheng Che Hung, Ko Kung Chen, Hsiu Mei Wu, Chao Bao Luo, Wei Fa Chu, Jia Sheng Hong, Chun Shien Frank Wu
BACKGROUND: Time-resolved rotational angiography (t-RA) enables interventionists to better comprehend complex arteriovenous malformations (AVMs), thereby facilitating endovascular treatment. However, its use in evaluating hemodynamic changes has rarely been explored. OBJECTIVE: This study uses t-RA to estimate intravascular flow in patients with AVM to compare this with flow in the normal population. METHODS: Patients with available t-RA scans were prospectively categorized into one of three groups: hemorrhagic AVM, non-hemorrhagic AVM and control...
October 9, 2017: Journal of Neurointerventional Surgery
https://www.readbyqxmd.com/read/28981515/the-heuristics-of-nurse-responsiveness-to-critical-patient-monitor-and-ventilator-alarms-in-a-private-room-neonatal-intensive-care-unit
#14
Rohan Joshi, Heidi van de Mortel, Loe Feijs, Peter Andriessen, Carola van Pul
AIM: Alarm fatigue is a well-recognized patient safety concern in intensive care settings. Decreased nurse responsiveness and slow response times to alarms are the potentially dangerous consequences of alarm fatigue. The aim of this study was to determine the factors that modulate nurse responsiveness to critical patient monitor and ventilator alarms in the context of a private room neonatal intensive care setting. METHODS: The study design comprised of both a questionnaire and video monitoring of nurse-responsiveness to critical alarms...
2017: PloS One
https://www.readbyqxmd.com/read/28977038/computational-model-of-interictal-discharges-triggered-by-interneurons
#15
Anton V Chizhov, Dmitry V Amakhin, Aleksey V Zaitsev
Interictal discharges (IIDs) are abnormal waveforms registered in the periods before or between seizures. IIDs that are initiated by GABAergic interneurons have not been mathematically modeled yet. In the present study, a mathematical model that describes the mechanisms of these discharges is proposed. The model is based on the experimental recordings of IIDs in pyramidal neurons of the rat entorhinal cortex and estimations of synaptic conductances during IIDs. IIDs were induced in cortico-hippocampal slices by applying an extracellular solution with 4-aminopyridine, high potassium, and low magnesium concentrations...
2017: PloS One
https://www.readbyqxmd.com/read/28935526/characterization-of-calcium-transients-during-early-embryogenesis-in-ascidians-ciona-robusta-ciona-intestinalis-type-a-and-ciona-savignyi
#16
Taichi Akahoshi, Kohji Hotta, Kotaro Oka
The calcium ion (Ca(2+)) is an important second messenger, and a rapid increase in Ca(2+) level (Ca(2+) transient) is involved in various aspects of embryogenesis. Although Ca(2+) transients play an important role in early developmental stages, little is known about their dynamics throughout embryogenesis. Here, Ca(2+) transients were characterized by visualizing Ca(2+) dynamics in developing chordate embryos using a fluorescent protein-based Ca(2+) indicator, GCaMP6s in combination with finely tuned microscopy...
November 15, 2017: Developmental Biology
https://www.readbyqxmd.com/read/28905516/simple-method-for-rf-pulse-measurement-using-gradient-reversal
#17
Vanessa L Landes, Krishna S Nayak
PURPOSE: To develop and evaluate a simple method for measuring the envelope of small-tip radiofrequency (RF) excitation waveforms in MRI, without extra hardware or synchronization. THEORY AND METHODS: Gradient reversal approach to evaluate RF (GRATER) involves RF excitation with a constant gradient and reversal of that gradient during signal reception to acquire the time-reversed version of an RF envelope. An outer-volume suppression prepulse is used optionally to preselect a uniform volume...
September 14, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28866489/simultaneous-ultrasonic-measurement-of-thickness-and-speed-of-sound-in-elastic-plates-using-coded-excitation-signals
#18
Daniel A Kiefer, Michael Fink, Stefan J Rupitsch
Layer thickness and speed of sound are important parameters for non-destructive testing applications. If one of the parameters is known, the other one can be determined by simple time-of-flight measurement of ultrasound. However, often these parameters are both unknown. In this contribution, we examine and adapt ultrasonic imaging techniques using coded excitation signals to simultaneously measure the thickness and speed of sound in homogeneous elastic plates of unknown material. Good axial resolution is required to measure thin samples...
August 30, 2017: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
https://www.readbyqxmd.com/read/28862159/temporary-persistence-of-conduction-block-after-prolonged-kilohertz-frequency-alternating-current-khfac-on-rat-sciatic-nerve
#19
Narendra Bhadra, Emily Foldes, Tina Vrabec, Kevin L Kilgore, Niloy Bhadra
Application of Kilohertz Frequency Alternating Current (KHFAC) waveforms can result in nerve conduction block that is induced in less than a second. Conduction recovers within seconds when KHFAC is applied for about 5 - 10 minutes. This study investigated the effect of repeated and prolonged application of KHFAC on rat Sciatic nerve with bipolar platinum electrodes. Approach: Varying durations of KHFAC at signal amplitudes for conduction block with intervals of no stimulus were studied. Nerve conduction was monitored by recording peak Gastrocnemius muscle force utilizing stimulation electrodes proximal (PS) and distal (DS) to a blocking electrode...
September 1, 2017: Journal of Neural Engineering
https://www.readbyqxmd.com/read/28834777/improved-sensitivity-for-w-band-gd-iii-gd-iii-and-nitroxide-nitroxide-deer-measurements-with-shaped-pulses
#20
Thorsten Bahrenberg, Yael Rosenski, Raanan Carmieli, Koby Zibzener, Mian Qi, Veronica Frydman, Adelheid Godt, Daniella Goldfarb, Akiva Feintuch
Chirp and shaped pulses have been recently shown to be highly advantageous for improving sensitivity in DEER (double electron-electron resonance, also called PELDOR) measurements due to their large excitation bandwidth. The implementation of such pulses for pulse EPR has become feasible due to the availability of arbitrary waveform generators (AWG) with high sampling rates to support pulse shaping for pulses with tens of nanoseconds duration. Here we present a setup for obtaining chirp pulses on our home-built W-band (95GHz) spectrometer and demonstrate its performance on Gd(III)-Gd(III) and nitroxide-nitroxide DEER measurements...
October 2017: Journal of Magnetic Resonance
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