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https://www.readbyqxmd.com/read/28291479/does-combat-hearing-preservation-equipment-affect-balance
#1
Art Ambrosio, Ali N Hoffer, Michael Hoffer
OBJECTIVES: (1) To investigate whether the occlusion effect and hearing attenuation produced by 3M Combat Arms Ear Plugs (CAEP) affects balance when compared to no hearing protection and (2) to investigate whether the occlusion effect and noise-canceling capabilities of the Nacre QuietPro system affects balance when compared to no hearing protection. METHODS: This prospective study collected pilot data for investigation of mechanisms of balance. 20 subjects with normal hearing and no vestibular dysfunction were tested with blackened goggles in three conditions-no hearing protection, CAEP, and with the Nacre QuietPro...
March 2017: Military Medicine
https://www.readbyqxmd.com/read/28269592/motion-noise-cancellation-in-seismocardiogram-of-ambulant-subjects-with-dual-sensors
#2
Chenxi Yang, Negar Tavassolian
This paper presents a dual-sensor method of extracting seismocardiographic (SCG) data from moving adult subjects using chest-worn wireless MEMS accelerometers. A digital signal processing (DSP) system including a normalized least means square (NLMS) adaptive filter is designed and tested in MATLAB. Data results from 10 subjects indicate a detection rate of 98.72% which outperforms our previously-proposed single-sensor scheme. Various sensor positons and possible failure mechanisms are also investigated to further evaluate the system performance...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28268326/asynchronous-noise-removal-for-earbud-based-ppg-sensors
#3
Yohei Tomita
This paper addresses motion noise removal for an earbud-based reflective photoplethysmographic (PPG) sensor. This system can be worn comfortably on the ear for a long time. However, body movements such as walking and running cause signal degradation. To improve signal quality, I propose a novel asynchronous noise removal method using only the right and left PPG signals. It cancels not only uncorrelated noise components but also asynchronous noise components by simply introducing a weight function in the calculation process of a Wiener filter...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28254082/ecg-artifact-cancellation-in-surface-emg-signals-by-fractional-order-calculus-application
#4
Nadica Miljković, Nenad Popović, Olivera Djordjević, Ljubica Konstantinović, Tomislav B Šekara
BACKGROUND AND OBJECTIVE: New aspects for automatic electrocardiography artifact removal from surface electromyography signals by application of fractional order calculus in combination with linear and nonlinear moving window filters are explored. Surface electromyography recordings of skeletal trunk muscles are commonly contaminated with spike shaped artifacts. This artifact originates from electrical heart activity, recorded by electrocardiography, commonly present in the surface electromyography signals recorded in heart proximity...
March 2017: Computer Methods and Programs in Biomedicine
https://www.readbyqxmd.com/read/28245585/a-novel-technique-for-fetal-ecg-extraction-using-single-channel-abdominal-recording
#5
Nannan Zhang, Jinyong Zhang, Hui Li, Omisore Olatunji Mumini, Oluwarotimi Williams Samuel, Kamen Ivanov, Lei Wang
Non-invasive fetal electrocardiograms (FECGs) are an alternative method to standard means of fetal monitoring which permit long-term continual monitoring. However, in abdominal recording, the FECG amplitude is weak in the temporal domain and overlaps with the maternal electrocardiogram (MECG) in the spectral domain. Research in the area of non-invasive separations of FECG from abdominal electrocardiograms (AECGs) is in its infancy and several studies are currently focusing on this area. An adaptive noise canceller (ANC) is commonly used for cancelling interference in cases where the reference signal only correlates with an interference signal, and not with a signal of interest...
February 24, 2017: Sensors
https://www.readbyqxmd.com/read/28236262/comparing-effects-between-music-intervention-and-aromatherapy-on-anxiety-of-patients-undergoing-mechanical-ventilation-in-the-intensive-care-unit-a-randomized-controlled-trial
#6
Chiu-Hsiang Lee, Chiung-Ling Lai, Yi-Hui Sung, Mei Yu Lai, Chung-Ying Lin, Long-Yau Lin
PURPOSE: Using patient-reported outcomes and physiological indicators to test the effects of music intervention and aromatherapy on reducing anxiety for intensive care unit (ICU) patients undergoing mechanical ventilation. METHODS: Patients with ICU admission duration >24 h were randomly assigned to a Music intervention group (n = 41), Aromatherapy group (n = 47), or Control group (rest only; n = 44). Each patient in the Music group listened to music; each patient in the Aromatherapy group received lavender essential oil massage on his/her back for 5 min; each patient in the Control group wore noise-canceling headphones...
February 24, 2017: Quality of Life Research
https://www.readbyqxmd.com/read/28227848/motion-noise-cancellation-in-seismocardiogram-of-ambulant-subjects-with-dual-sensors
#7
Chenxi Yang, Negar Tavassolian, Chenxi Yang, Negar Tavassolian, Negar Tavassolian, Chenxi Yang
This paper presents a dual-sensor method of extracting seismocardiographic (SCG) data from moving adult subjects using chest-worn wireless MEMS accelerometers. A digital signal processing (DSP) system including a normalized least means square (NLMS) adaptive filter is designed and tested in MATLAB. Data results from 10 subjects indicate a detection rate of 98.72% which outperforms our previously-proposed single-sensor scheme. Various sensor positons and possible failure mechanisms are also investigated to further evaluate the system performance...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226487/asynchronous-noise-removal-for-earbud-based-ppg-sensors
#8
Yohei Tomita, Yohei Tomita, Yohei Tomita
This paper addresses motion noise removal for an earbud-based reflective photoplethysmographic (PPG) sensor. This system can be worn comfortably on the ear for a long time. However, body movements such as walking and running cause signal degradation. To improve signal quality, I propose a novel asynchronous noise removal method using only the right and left PPG signals. It cancels not only uncorrelated noise components but also asynchronous noise components by simply introducing a weight function in the calculation process of a Wiener filter...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28179732/a-microfabricated-optically-pumped-magnetic-gradiometer
#9
D Sheng, A R Perry, S P Krzyzewski, S Geller, J Kitching, S Knappe
We report on the development of a microfabricated atomic magnetic gradiometer based on optical spectroscopy of alkali atoms in the vapor phase. The gradiometer, which operates in the spin-exchange relaxation free regime, has a length of 60 mm and cross sectional diameter of 12 mm, and consists of two chip-scale atomic magnetometers which are interrogated by a common laser light. The sensor can measure differences in magnetic fields, over a 20 mm baseline, of 10 fT/[Formula: see text] at frequencies above 20 Hz...
January 16, 2017: Applied Physics Letters
https://www.readbyqxmd.com/read/28177299/development-of-an-improved-wearable-device-for-core-body-temperature-monitoring-based-on-the-dual-heat-flux-principle
#10
Jingjie Feng, Congcong Zhou, Cheng He, Yuan Li, Xuesong Ye
OBJECTIVE: In this paper, a miniaturized wearable core body temperature (CBT) monitoring system based on the dual heat flux (DHF) principle was developed. APPROACH: By interspersing calcium carbonate powder in PolyDimethylsiloxane (PDMS), a reformative heat transfer medium was produced to reduce the thermal equilibrium time. Besides, a least mean square (LMS) algorithm based active noise cancellation (ANC) method was adopted to diminish the impact of ambient temperature fluctuations...
February 8, 2017: Physiological Measurement
https://www.readbyqxmd.com/read/28174614/weak-electric-fields-detectability-in-a-noisy-neural-network
#11
Jia Zhao, Bin Deng, Yingmei Qin, Cong Men, Jiang Wang, Xile Wei, Jianbing Sun
We investigate the detectability of weak electric field in a noisy neural network based on Izhikevich neuron model systematically. The neural network is composed of excitatory and inhibitory neurons with similar ratio as that in the mammalian neocortex, and the axonal conduction delays between neurons are also considered. It is found that the noise intensity can modulate the detectability of weak electric field. Stochastic resonance (SR) phenomenon induced by white noise is observed when the weak electric field is added to the network...
February 2017: Cognitive Neurodynamics
https://www.readbyqxmd.com/read/28158119/development-of-a-compact-optical-absolute-frequency-reference-for-space-with-10-sup-15-sup-instability
#12
Thilo Schuldt, Klaus Döringshoff, Evgeny V Kovalchuk, Anja Keetman, Julia Pahl, Achim Peters, Claus Braxmaier
We report on a compact and ruggedized setup for laser frequency stabilization employing Doppler-free spectroscopy of molecular iodine near 532 nm. Using a 30 cm long iodine cell in a triple-pass configuration in combination with noise-canceling detection and residual amplitude modulation control, a frequency instability of 6×10<sup>-15</sup> at 1 s integration time and a Flicker noise floor below 3×10<sup>-15</sup> for integration times between 100 and 1000 s was found. A specific assembly-integration technology was applied for the realization of the spectroscopy setup, ensuring high beam pointing stability and high thermal and mechanical rigidity...
February 1, 2017: Applied Optics
https://www.readbyqxmd.com/read/28125160/design-of-high-quality-chemical-xor-gates-with-noise-reduction
#13
Mackenna L Wood, Sergii Domanskyi, Vladimir Privman
We describe a chemical XOR gate design that realizes gate-response function with filtering properties. Such gate-response function is flat (has small gradients) at and in the vicinity of all the four binary-input logic points, resulting in analog noise suppression. The gate functioning involves cross-reaction of the inputs represented by pairs of chemicals to produce a practically zero output when both are present and nearly equal. This cross-reaction processing step is also designed to result in filtering at low output intensities by canceling out the inputs if one of the latter has low intensity as compared to the other...
January 26, 2017: Chemphyschem: a European Journal of Chemical Physics and Physical Chemistry
https://www.readbyqxmd.com/read/28098201/fiber-laser-based-ultrasound-sensor-for-photoacoustic-imaging
#14
Yizhi Liang, Long Jin, Lidai Wang, Xue Bai, Linghao Cheng, Bai-Ou Guan
Photoacoustic imaging, especially for intravascular and endoscopic applications, requires ultrasound probes with miniature size and high sensitivity. In this paper, we present a new photoacoustic sensor based on a small-sized fiber laser. Incident ultrasound waves exert pressures on the optical fiber laser and induce harmonic vibrations of the fiber, which is detected by the frequency shift of the beating signal between the two orthogonal polarization modes in the fiber laser. This ultrasound sensor presents a noise-equivalent pressure of 40 Pa over a 50-MHz bandwidth...
January 18, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28092543/a-robust-wrap-reduction-algorithm-for-fringe-projection-profilometry-and-applications-in-magnetic-resonance-imaging
#15
Miguel Arevalillo-Herraez, Maximo Cobos, Miguel Garcia-Pineda
In this paper, we present an effective algorithm to reduce the number of wraps in a 2D phase signal provided as input. The technique is based on an accurate estimate of the fundamental frequency of a 2D complex signal with the phase given by the input, and the removal of a dependent additive term from the phase map. Unlike existing methods based on the discrete Fourier transform (DFT), the frequency is computed by using noise-robust estimates that are not restricted to integer values. Then, to deal with the problem of a non-integer shift in the frequency domain, an equivalent operation is carried out on the original phase signal...
March 2017: IEEE Transactions on Image Processing: a Publication of the IEEE Signal Processing Society
https://www.readbyqxmd.com/read/28059760/volcanic-tremor-and-plume-height-hysteresis-from-pavlof-volcano-alaska
#16
David Fee, Matthew M Haney, Robin S Matoza, Alexa R Eaton, Peter Cervelli, David J Schneider, Alexandra M Iezzi
The March 2016 eruption of Pavlof Volcano, Alaska, produced an ash plume that caused the cancellation of more than 100 flights in North America. The eruption generated strong tremor that was recorded by seismic and remote low-frequency acoustic (infrasound) stations, including the EarthScope Transportable Array. The relationship between the tremor amplitudes and plume height changes considerably between the waxing and waning portions of the eruption. Similar hysteresis has been observed between seismic river noise and discharge during storms, suggesting that flow and erosional processes in both rivers and volcanoes can produce irreversible structural changes that are detectable in geophysical data...
January 6, 2017: Science
https://www.readbyqxmd.com/read/28055986/robust-heart-rate-estimation-using-wrist-type-photoplethysmographic-signals-during-physical-exercise-an-approach-based-on-adaptive-filtering
#17
Sibylle Fallet, Jean-Marc Vesin
Photoplethysmographic (PPG) signals are easily corrupted by motion artifacts when the subjects perform physical exercise. This paper introduces a two-step processing scheme to estimate heart rate (HR) from wrist-type PPG signals strongly corrupted by motion artifacts. Adaptive noise cancellation, using normalized least-mean-square algorithm, is first performed to attenuate motion artifacts and reconstruct multiple PPG waveforms from different combinations of corrupted PPG waveforms and accelerometer data. An adaptive band-pass filter is then used to track the common instantaneous frequency component (i...
January 5, 2017: Physiological Measurement
https://www.readbyqxmd.com/read/28047845/we-ab-207a-01-best-in-physics-imaging-high-resolution-cone-beam-ct-of-the-extremities-and-cancellous-bone-architecture-with-a-cmos-detector
#18
Q Cao, M Brehler, A Sisniega, E Marinetto, A Zyazin, I Peters, J Stayman, J Yorkston, J Siewerdsen, W Zbijewski
PURPOSE: Extremity cone-beam CT (CBCT) with an amorphous silicon (aSi) flat-panel detector (FPD) provides low-dose volumetric imaging with high spatial resolution. We investigate the performance of the newer complementary metal-oxide semiconductor (CMOS) detectors to enhance resolution of extremities CBCT to ∼0.1 mm, enabling morphological analysis of trabecular bone. Quantitative in-vivo imaging of bone microarchitecture could present an important advance for osteoporosis and osteoarthritis diagnosis and therapy assessment...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28040042/multichannel-active-noise-control-for-spatially-sparse-noise-fields
#19
Jihui Zhang, Thushara D Abhayapala, Prasanga N Samarasinghe, Wen Zhang, Shouda Jiang
Multi-channel active noise control (ANC) is currently an attractive solution for the attenuation of low-frequency noise fields, in three-dimensional space. This paper develops a controller for the case when the noise source components are sparsely distributed in space. The anti-noise signals are designed as in conventional ANC to minimize the residual errors but with an additional term containing an ℓl norm regularization applied to the signal magnitude. This results in that only secondary sources close to the noise sources are required to be active for cancellation of sparse noise fields...
December 2016: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/28030519/incorporating-a-computerized-cognitive-battery-into-the-emergency-department-care-of-pediatric-mild-traumatic-brain-injuries-is-it-feasible
#20
Aneesh M Khetani, Brian L Brooks, Angelo Mikrogianakis, Karen M Barlow
OBJECTIVES: The use of computers to test cognitive function acutely after a concussion is becoming increasingly popular, especially after sport-related concussion. Although commonly performed in the community, it is not yet performed routinely in the emergency department (ED), where most injured children present. The challenges of performing computerized cognitive testing (CCT) in a busy ED are considerable. The aim of this study was to evaluate the feasibility of CCT in the pediatric ED after concussion...
December 28, 2016: Pediatric Emergency Care
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