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https://www.readbyqxmd.com/read/27918482/fuzzy-computing-model-of-activity-recognition-on-wsn-movement-data-for-ubiquitous-healthcare-measurement
#1
Shu-Yin Chiang, Yao-Chiang Kan, Yun-Shan Chen, Ying-Ching Tu, Hsueh-Chun Lin
Ubiquitous health care (UHC) is beneficial for patients to ensure they complete therapeutic exercises by self-management at home. We designed a fuzzy computing model that enables recognizing assigned movements in UHC with privacy. The movements are measured by the self-developed body motion sensor, which combines both accelerometer and gyroscope chips to make an inertial sensing node compliant with a wireless sensor network (WSN). The fuzzy logic process was studied to calculate the sensor signals that would entail necessary features of static postures and dynamic motions...
December 3, 2016: Sensors
https://www.readbyqxmd.com/read/27914438/dynamic-sound-scattering-field-fluctuation-spectroscopy-with-singly-scattered-ultrasound-in-the-near-and-far-fields
#2
M L Cowan, J H Page, T Norisuye, D A Weitz
Dynamic sound scattering (DSS) is a powerful acoustic technique for investigating the motion of particles or other inclusions inside an evolving medium. In DSS, this dynamic information is obtained by measuring the field autocorrelation function of the temporal fluctuations of singly scattered acoustic waves. The technique was initially introduced 15 years ago, but its technical aspects were not adequately discussed then. This paper addresses the need for a more complete account of the method by describing in detail two different implementations of this sound scattering technique, one of which is specifically adapted to a common experimental situation in ultrasonics...
September 2016: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/27911808/exploration-of-joint-redundancy-but-not-task-space-variability-facilitates-supervised-motor-learning
#3
Puneet Singh, Sumitash Jana, Ashitava Ghosal, Aditya Murthy
The number of joints and muscles in a human arm is more than what is required for reaching to a desired point in 3D space. Although previous studies have emphasized how such redundancy and the associated flexibility may play an important role in path planning, control of noise, and optimization of motion, whether and how redundancy might promote motor learning has not been investigated. In this work, we quantify redundancy space and investigate its significance and effect on motor learning. We propose that a larger redundancy space leads to faster learning across subjects...
November 29, 2016: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/27908178/a-probability-based-multi-cycle-sorting-method-for-4d-mri-a-simulation-study
#4
Xiao Liang, Fang-Fang Yin, Yilin Liu, Jing Cai
PURPOSE: To develop a novel probability-based sorting method capable of generating multiple breathing cycles of 4D-MRI images and to evaluate performance of this new method by comparing with conventional phase-based methods in terms of image quality and tumor motion measurement. METHODS: Based on previous findings that breathing motion probability density function (PDF) of a single breathing cycle is dramatically different from true stabilized PDF that resulted from many breathing cycles, it is expected that a probability-based sorting method capable of generating multiple breathing cycles of 4D images may capture breathing variation information missing from conventional single-cycle sorting methods...
December 2016: Medical Physics
https://www.readbyqxmd.com/read/27903640/differential-effect-of-visual-motion-adaption-upon-visual-cortical-excitability
#5
Astrid J A Lubeck, Angelique Van Ombergen, Hena Ahmad, Jelte E Bos, Floris L Wuyts, Adolfo M Bronstein, Qadeer Arshad
OBJECTIVE: 1) To probe the effects of visual motion adaptation upon, early visual and V5/MT cortical excitability and 2) To investigate whether or not changes in cortical excitability following visual motion adaptation are related to the degree of visual dependency, i.e. an overreliance on visual cues compared to vestibular or proprioceptive cues. METHODS: Participants were exposed to a roll-motion visual stimulus pre, during and post visual motion adaptation. At these stages 20 TMS pulses at phosphene-threshold values were applied over early visual and V5/MT cortical areas from which the probability of eliciting a phosphene was calculated...
November 30, 2016: Journal of Neurophysiology
https://www.readbyqxmd.com/read/27903636/spatiotopic-maps-during-dynamic-head-tilt
#6
Kyriaki Mikellidou, Marco Turi, David Charles Burr
Humans maintain a stable representation of the visual world effortlessly, despite constant movements of the eyes, head and body, across multiple planes. Whereas visual stability in the face of saccadic eye-movements has been intensely researched, fewer studies have investigated retinal image transformations induced by head movements, especially in the frontal plane. Unlike head rotations in the horizontal and sagittal planes, tilting the head in the frontal plane is only partially counteracted by torsional eye-movements, and consequently induces a distortion of the retinal image to which we seem to be completely oblivious...
November 30, 2016: Journal of Neurophysiology
https://www.readbyqxmd.com/read/27895994/motion-corrected-fourier-ptychography
#7
Liheng Bian, Guoan Zheng, Kaikai Guo, Jinli Suo, Changhuei Yang, Feng Chen, Qionghai Dai
Fourier ptychography (FP) is a recently proposed computational imaging technique for high space-bandwidth product imaging. In real setups such as endoscope and transmission electron microscope, the common sample motion largely degrades the FP reconstruction and limits its practicability. In this paper, we propose a novel FP reconstruction method to efficiently correct for unknown sample motion. Specifically, we adaptively update the sample's Fourier spectrum from low spatial-frequency regions towards high spatial-frequency ones, with an additional motion recovery and phase-offset compensation procedure for each sub-spectrum...
November 1, 2016: Biomedical Optics Express
https://www.readbyqxmd.com/read/27895569/influence-of-lumbar-muscle-fatigue-on-trunk-adaptations-during-sudden-external-perturbations
#8
Jacques Abboud, François Nougarou, Arnaud Lardon, Claude Dugas, Martin Descarreaux
Introduction: When the spine is subjected to perturbations, neuromuscular responses such as reflex muscle contractions contribute to the overall balance control and spinal stabilization mechanisms. These responses are influenced by muscle fatigue, which has been shown to trigger changes in muscle recruitment patterns. Neuromuscular adaptations, e.g., attenuation of reflex activation and/or postural oscillations following repeated unexpected external perturbations, have also been described. However, the characterization of these adaptations still remains unclear...
2016: Frontiers in Human Neuroscience
https://www.readbyqxmd.com/read/27895550/closed-loop-task-difficulty-adaptation-during-virtual-reality-reach-to-grasp-training-assisted-with-an-exoskeleton-for-stroke-rehabilitation
#9
Florian Grimm, Georgios Naros, Alireza Gharabaghi
Stroke patients with severe motor deficits of the upper extremity may practice rehabilitation exercises with the assistance of a multi-joint exoskeleton. Although this technology enables intensive task-oriented training, it may also lead to slacking when the assistance is too supportive. Preserving the engagement of the patients while providing "assistance-as-needed" during the exercises, therefore remains an ongoing challenge. We applied a commercially available seven degree-of-freedom arm exoskeleton to provide passive gravity compensation during task-oriented training in a virtual environment...
2016: Frontiers in Neuroscience
https://www.readbyqxmd.com/read/27891684/changes-in-visibility-as-a-function-of-spatial-frequency-and-microsaccade-occurrence
#10
Francisco M Costela, Michael B McCamy, Mary Coffelt, Jorge Otero-Millan, Stephen Macknik, Susana Martinez-Conde
Fixational eye movements (FEM), including microsaccades, drift, and tremor, shift our eye position during ocular fixation, producing retinal motion that is thought to help visibility by counteracting neural adaptation to unchanging stimulation. Yet, how each FEM type influences this process is still debated. Recent studies found little to no relationship between microsaccades and visual perception of spatial frequencies (SF), and concluded that any effects microsaccades may have on vision do not extend to the SF domain...
November 27, 2016: European Journal of Neuroscience
https://www.readbyqxmd.com/read/27891683/supramolecular-adaptive-nanomotors-with-magnetotaxis-behavior
#11
Fei Peng, Yingfeng Tu, Yongjun Men, Jan C M van Hest, Daniela A Wilson
With a convenient bottom-up approach, magnetic metallic nickel is grown in situ of a supramolecular nanomotor using the catalytic activities of preloaded platinum nanoparticles. After introducing magnetic segments, simultaneous guidance and steering of catalytically powered motors with additional magnetic fields are achieved. Guided motion in a tissue model is demonstrated.
November 28, 2016: Advanced Materials
https://www.readbyqxmd.com/read/27886835/shoulder-injuries-in-the-overhead-throwing-athlete
#12
REVIEW
Ryan A Mlynarek, Simon Lee, Asheesh Bedi
The overhead pitching motion is a coordinated sequence of movements that subjects the shoulder to extreme forces. The ultimate goal of this complex, dynamic activity is to generate high ball velocity and accuracy. In doing so, repetitive throwing can cause adaptive and pathologic changes in the thrower's shoulder. This article reviews the relevant shoulder anatomy, the kinetic chain, and throwing mechanics, as well as common shoulder injuries and surgical options for the treating orthopedic surgeon.
February 2017: Hand Clinics
https://www.readbyqxmd.com/read/27883179/evidence-that-an-internal-schema-adapts-swallowing-to-upper-airway-requirements
#13
Seng Mun Wong, Rickie J Domangue, Sidney Fels, Christy L Ludlow
Hyoid and laryngeal movements contribute to laryngeal vestibule closure and upper esophageal sphincter opening during swallowing. Evidence of an internal sensorimotor scaling system allowing individuals to achieve these functional goals is lacking. In speech, speakers adjust their articulatory movement magnitude according to the movement distance required to reach an articulatory target for intelligible speech. We investigated if swallowing is similar in that movement amplitude may be scaled by the functional goal for airway protection during swallowing, rather than by head and neck size...
November 24, 2016: Journal of Physiology
https://www.readbyqxmd.com/read/27881303/the-serotonergic-system-tracks-the-outcomes-of-actions-to-mediate-short-term-motor-learning
#14
Takashi Kawashima, Maarten F Zwart, Chao-Tsung Yang, Brett D Mensh, Misha B Ahrens
To execute accurate movements, animals must continuously adapt their behavior to changes in their bodies and environments. Animals can learn changes in the relationship between their locomotor commands and the resulting distance moved, then adjust command strength to achieve a desired travel distance. It is largely unknown which circuits implement this form of motor learning, or how. Using whole-brain neuronal imaging and circuit manipulations in larval zebrafish, we discovered that the serotonergic dorsal raphe nucleus (DRN) mediates short-term locomotor learning...
November 3, 2016: Cell
https://www.readbyqxmd.com/read/27874033/influence-of-combined-fundamental-potentials-in-a-nonlinear-vibration-energy-harvester
#15
Pranay Podder, Dhiman Mallick, Andreas Amann, Saibal Roy
Ambient mechanical vibrations have emerged as a viable energy source for low-power wireless sensor nodes aiming the upcoming era of the 'Internet of Things'. Recently, purposefully induced dynamical nonlinearities have been exploited to widen the frequency spectrum of vibration energy harvesters. Here we investigate some critical inconsistencies between the theoretical formulation and applications of the bistable Duffing nonlinearity in vibration energy harvesting. A novel nonlinear vibration energy harvesting device with the capability to switch amidst individually tunable bistable-quadratic, monostable-quartic and bistable-quartic potentials has been designed and characterized...
November 22, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27871854/rate-adaptive-pacing-in-an-intracardiac-pacemaker
#16
Michael Lloyd, Dwight Reynolds, Todd Sheldon, Kurt Stromberg, J Harrison Hudnall, Wade M Demmer, Razali Omar, Philippe Ritter, John Hummel, Lluís Mont, Clemens Steinwender, Gabor Z Duray
BACKGROUND: The Micra transcatheter pacemaker was designed to have similar functionality to conventional transvenous VVIR pacing systems. It provides rate adaptive pacing using a programmable 3-axis accelerometer designed to detect patient activity in the presence of cardiac motion. OBJECTIVE: We evaluated the system's performance during treadmill tests to maximum exertion in a subset of patients within the Micra TPS Global Clinical Trial. METHODS: Patients underwent treadmill testing at 3 or 6-months post-implant with algorithm programming at physician discretion...
November 15, 2016: Heart Rhythm: the Official Journal of the Heart Rhythm Society
https://www.readbyqxmd.com/read/27870999/sparse-bayesian-registration-of-medical-images-for-self-tuning-of-parameters-and-spatially-adaptive-parametrization-of-displacements
#17
Loïc Le Folgoc, Hervé Delingette, Antonio Criminisi, Nicholas Ayache
We extend Bayesian models of non-rigid image registration to allow not only for the automatic determination of registration parameters (such as the trade-off between image similarity and regularization functionals), but also for a data-driven, multiscale, spatially adaptive parametrization of deformations. Adaptive parametrizations have been used with success to promote both the regularity and accuracy of registration schemes, but so far on non-probabilistic grounds - either as part of multiscale heuristics, or on the basis of sparse optimization...
November 9, 2016: Medical Image Analysis
https://www.readbyqxmd.com/read/27870605/age-related-differences-in-locomotor-strategies-during-adaptive-walking
#18
Kristin A Lowry, Katherine Sebastian, Subashan Perera, Jessie Van Swearingen, Ann L Smiley-Oyen
Simultaneous control of lower limb stepping movements and trunk motion is important for skilled walking; adapting gait to environmental constraints requires frequent alternations in stepping and trunk motion. These alterations provide a window into the locomotor strategies adopted by the walker. The authors examined gait strategies in young and healthy older adults when manipulating step width. Anteroposterior (AP) and mediolateral (ML) smoothness (quantified by harmonic ratios) and stepping consistency (quantified by gait variability) were analyzed during narrow and wide walking while controlling cadence to preferred pace...
November 21, 2016: Journal of Motor Behavior
https://www.readbyqxmd.com/read/27863279/evidence-of-compensatory-joint-kinetics-during-stair-ascent-and-descent-in-parkinson-s-disease
#19
Zachary J Conway, Peter A Silburn, Tim Blackmore, Michael H Cole
BACKGROUND: Stair ambulation is a challenging activity of daily life that requires larger joint moments than walking. Stabilisation of the body and prevention of lower limb collapse during this task depends upon adequately-sized hip, knee and ankle extensor moments. However, people with Parkinson's disease (PD) often present with strength deficits that may impair their capacity to control the lower limbs and ultimately increase their falls risk. OBJECTIVE: To investigate hip, knee and ankle joint moments during stair ascent and descent and determine the contribution of these joints to the body's support in people with PD...
November 9, 2016: Gait & Posture
https://www.readbyqxmd.com/read/27861541/accuracy-and-reliability-of-the-kinect-version-2-for-clinical-measurement-of-motor-function
#20
Karen Otte, Bastian Kayser, Sebastian Mansow-Model, Julius Verrel, Friedemann Paul, Alexander U Brandt, Tanja Schmitz-Hübsch
BACKGROUND: The introduction of low cost optical 3D motion tracking sensors provides new options for effective quantification of motor dysfunction. OBJECTIVE: The present study aimed to evaluate the Kinect V2 sensor against a gold standard motion capture system with respect to accuracy of tracked landmark movements and accuracy and repeatability of derived clinical parameters. METHODS: Nineteen healthy subjects were concurrently recorded with a Kinect V2 sensor and an optical motion tracking system (Vicon)...
2016: PloS One
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