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https://www.readbyqxmd.com/read/28454138/programmable-single-pixel-based-broadband-stimulated-raman-scattering
#1
Pascal Berto, Camille Scotté, Frédéric Galland, Hervè Rigneault, Hilton B de Aguiar
We report a simple add-on for broadband stimulated Raman scattering (SRS) microscopes to enable fast and programmable spectroscopy acquisition. It comprises a conventional dispersive spectrometer layout incorporating a fast digital micromirror device (DMD). The approach is validated by acquiring SRS spectra of standard chemicals. We demonstrate a DMD's advantage in broadband SRS by showing higher signal-to-noise ratio using a multiplexed Hadamard spectral basis and compressive sensing detection. Our results apply to a variety of frequency-domain pump-probe spectroscopy...
May 1, 2017: Optics Letters
https://www.readbyqxmd.com/read/28447744/cyclic-compression-stimulates-osteoblast-differentiation-via-activation-of-the-wnt-%C3%AE-catenin-signaling-pathway
#2
Xi Chen, Jianmin Guo, Yu Yuan, Zhongguang Sun, Binglin Chen, Xiaoyang Tong, Lingli Zhang, Chao Shen, Jun Zou
It is widely accepted that mechanical stress is an important factor in bone associated cell differentiation, including that of mesenchymal stem cells, osteoblasts and osteocytes. The present study aimed to determine the effect of mechanical cyclic compressive load on osteoblast differentiation, and whether this was associated with activation of the wingless‑type (Wnt)/β-catenin signaling pathway. Using a 3D scaffold model, MC3T3‑E1 cells were exposed to cyclic compressive loading via the Flexcell‑5000C™ Compression system...
March 15, 2017: Molecular Medicine Reports
https://www.readbyqxmd.com/read/28442987/compression-at-myofascial-trigger-point-on-chronic-neck-pain-provides-pain-relief-through-the-prefrontal-cortex-and-autonomic-nervous-system-a-pilot-study
#3
Yoshiki Morikawa, Kouich Takamoto, Hiroshi Nishimaru, Toru Taguchi, Susumu Urakawa, Shigekazu Sakai, Taketoshi Ono, Hisao Nishijo
Compression at myofascial trigger points (MTrPs), known as "ischemic compression," has been reported to provide immediate relief of musculoskeletal pain and reduce the sympathetic activity that exacerbates chronic pain. We conducted a pilot study to investigate the possible involvement of the prefrontal cortex in pain relief obtained by MTrP compression in the present study, and analyzed the relationships among prefrontal hemodynamic activity, activity of the autonomic nervous system, and subjective pain in patients with chronic neck pain, with and without MTrP compression...
2017: Frontiers in Neuroscience
https://www.readbyqxmd.com/read/28441329/implementation-of-an-electronic-ionosonde-to-monitor-the-earth-s-ionosphere-via-a-projected-column-through-usrp
#4
Jhon Jairo Barona Mendoza, Carlos Fernando Quiroga Ruiz, Carlos Rafael Pinedo Jaramillo
This document illustrates the processes carried out for the construction of an ionospheric sensor or ionosonde, from a universal software radio peripheral (USRP), and its programming using GNU-Radio and MATLAB. The development involved the in-depth study of the characteristics of the ionosphere, to apply the corresponding mathematical models used in the radar-like pulse compression technique and matched filters, among others. The sensor operates by firing electromagnetic waves in a frequency sweep, which are reflected against the ionosphere and are received on its return by the receiver of the instrument, which calculates the reflection height through the signal offset...
April 25, 2017: Sensors
https://www.readbyqxmd.com/read/28437225/neck-collar-with-mild-jugular-vein-compression-ameliorates-brain-activation-changes-during-a-working-memory-task-after-a-season-of-high-school-football
#5
Weihong Yuan, James Leach, Thomas Maloney, Mekibib Altaye, David Smith, Paul Gubanich, Kim Barber-Foss, Staci Thomas, Christopher DiCesare, Adam Kiefer, Gregory D Myer
Emerging evidence indicates that repetitive head impacts, even at a sub-concussive level, may result in exacerbated or prolonged neurologic deficits in athletes. This study aimed to: 1) quantify the effect of repetitive head impacts on the alteration of neuronal activity based on fMRI of working memory after a high school football season; and 2) determine whether a neck collar that applies mild jugular vein compression to reduce brain energy absorption in head impact through slosh mitigation can ameliorate the altered fMRI activation during a working memory task...
February 18, 2017: Journal of Neurotrauma
https://www.readbyqxmd.com/read/28428427/microtubules-acquire-resistance-from-mechanical-breakage-through-intralumenal-acetylation
#6
Zhenjie Xu, Laura Schaedel, Didier Portran, Andrea Aguilar, Jérémie Gaillard, M Peter Marinkovich, Manuel Théry, Maxence V Nachury
Eukaryotic cells rely on long-lived microtubules for intracellular transport and as compression-bearing elements. We considered that long-lived microtubules are acetylated inside their lumen and that microtubule acetylation may modify microtubule mechanics. Here, we found that tubulin acetylation is required for the mechanical stabilization of long-lived microtubules in cells. Depletion of the tubulin acetyltransferase TAT1 led to a significant increase in the frequency of microtubule breakage. Nocodazole-resistant microtubules lost upon removal of acetylation were largely restored by either pharmacological or physical removal of compressive forces...
April 21, 2017: Science
https://www.readbyqxmd.com/read/28424226/objective-measurement-of-adherence-to-out-patient-airway-clearance-therapy-by-high-frequency-chest-wall-compression-in-cystic-fibrosis
#7
Christina L Mikesell, Robert R Kempainen, Theresa A Laguna, Jeremiah S Menk, Andrew R Wey, Philippe R Gaillard, Warren E Regelmann
BACKGROUND: Objective measures of adherence to high-frequency chest wall compression (HFCWC, also known as high frequency chest wall oscillation, HFCWO), a form of airway clearance therapy for patients with cystic fibrosis, are lacking. We used a novel electronic monitoring device integrated into an HFCWC vest to measure adherence compared with self-reported adherence. We determined factors that influenced adherence and how adherence correlated with baseline pulmonary function and pulmonary exacerbations...
April 19, 2017: Respiratory Care
https://www.readbyqxmd.com/read/28422488/pressure-driven-isostructural-phase-transition-in-innbo4-in-situ-experimental-and-theoretical-investigations
#8
Alka B Garg, Daniel Errandonea, Catalin Popescu, Domingo Martinez-García, Julio Pellicer-Porres, Placida Rodríguez-Hernández, Alfonso Muñoz, Pablo Botella, Vanesa P Cuenca-Gotor, Juan Angel Sans
The high-pressure behavior of technologically important visible-light photocatalytic semiconductor InNbO4, adopting a monoclinic wolframite-type structure at ambient conditions, was investigated using synchrotron-based X-ray diffraction, Raman spectroscopic measurements, and first-principles calculations. The experimental results indicate the occurrence of a pressure-induced isostructural phase transition in the studied compound beyond 10.8 GPa. The large volume collapse associated with the phase transition and the coexistence of two phases observed over a wide range of pressure shows the nature of transition to be first-order...
April 19, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28401940/optical-nonlinearity-enhancement-with-graphene-decorated-silicon-waveguides
#9
Atsushi Ishizawa, Rai Kou, Takahiro Goto, Tai Tsuchizawa, Nobuyuki Matsuda, Kenichi Hitachi, Tadashi Nishikawa, Koji Yamada, Tetsuomi Sogawa, Hideki Gotoh
Broadband on-chip optical frequency combs (OFCs) are important for expanding the functionality of photonic integrated circuits. Here, we demonstrate a huge local optical nonlinearity enhancement using graphene. A waveguide is decorated with graphene by precisely manipulating graphene's area and position. Our approach simultaneously achieves both an extremely efficient supercontinuum and ultra-short pulse generation. With our graphene-decorated silicon waveguide (G-SWG), we have achieved enhanced spectral broadening of femtosecond pump pulses, along with an eightfold increase in the output optical intensity at a wavelength approximately 200 nm shorter than that of the pump pulses...
April 12, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28400863/prevalence-of-the-short-face-pattern-in-individuals-of-bauru-brazil
#10
Douglas Rezende Bastos, Ana Cláudia de Castro Ferreira Conti, Leopoldino Capelozza Filho, Renata Rodrigues de Almeida-Pedrin, Maurício de Almeida Cardoso
AIM: This study aimed at assessing the prevalence and severity of short face pattern in ethnically different individuals. MATERIAL AND METHODS: The sample comprised 4,409 Brazilians (2,192 females and 2,217 males), with a mean age of 13 years, enrolled in secondary schools in the municipality of Bauru. The sample inclusion criteria involved subjects with vertically impaired facial relationship based on excessive lip compression, when standing at natural head position, with the lips at rest...
2017: Open Dentistry Journal
https://www.readbyqxmd.com/read/28400132/utility-of-a-simple-lighting-device-to-improve-chest-compressions-learning
#11
L González-Calvete, R Barcala-Furelos, J D Moure-González, C Abelairas-Gómez, A Rodríguez-Núñez
INTRODUCTION: The recommendations on cardiopulmonary resuscitation (CPR) emphasize the quality of the manoeuvres, especially chest compressions (CC). Audiovisual feedback devices could improve the quality of the CC during CPR. The aim of this study was to evaluate the usefulness of a simple lighting device as a visual aid during CPR on a mannequin. MATERIAL AND METHODS: Twenty-two paediatricians who attended an accredited paediatric CPR course performed, in random order, 2min of CPR on a mannequin without and with the help of a simple lighting device, which flashes at a frequency of 100 cycles per minute...
April 8, 2017: Revista Española de Anestesiología y Reanimación
https://www.readbyqxmd.com/read/28392194/extended-bandwidth-nonlinear-frequency-compression-in-mandarin-speaking-hearing-aid-users
#12
Wen-Hsuan Tseng, Dun-Lieh Hsieh, Wan-Ting Shih, Tien-Chen Liu
BACKGROUND/PURPOSE: The high frequency information of consonant messages is important for recognition of speech. Recently, the nonlinear frequency compression (NLFC) technique has been shown to improve the speech perception in patients with high frequency hearing loss. In Mandarin, seven consonants are located over 10-16 kHz. Extended-bandwidth (EB) NLFC may provide an additional benefit for recognition of Mandarin words. The purpose of this study was to explore the effects of NLFC and EB-NLFC on Mandarin word recognition in patients with high frequency hearing loss...
April 6, 2017: Journal of the Formosan Medical Association, Taiwan Yi Zhi
https://www.readbyqxmd.com/read/28381050/design-and-simulation-of-a-single-cycle-source-tunable-from-2-to-10-micrometers
#13
Wenkai Li, Yanyan Li, Yi Xu, Xiaoyang Guo, Jun Lu, Pengfei Wang, Yuxin Leng
We present the design of a novel single-cycle infrared source tunable from 2 to 10 μm. We simulate the optical parametric amplification (OPA) in BBO and the difference frequency generation (DFG) in AGS based on coupled second-order three-wave nonlinear propagation equations. We combine this with the unidirectional pulse propagation equation, which models the generation of the initial supercontinuum seed in sapphire and the final self-compression in YAG, ZnS, and GaAs, respectively. The obtained results indicate that single-cycle pulses can be produced in a tunable range of 2 to 10 μm...
March 20, 2017: Optics Express
https://www.readbyqxmd.com/read/28380883/generation-of-broadband-mid-ir-and-uv-light-in-gas-filled-single-ring-hollow-core-pcf
#14
Marco Cassataro, David Novoa, Mehmet C Günendi, Nitin N Edavalath, Michael H Frosz, John C Travers, Philip St J Russell
We report generation of an ultrafast supercontinuum extending into the mid- infrared in gas-filled single-ring hollow-core photonic crystal fiber (SR-PCF) pumped by 1.7 µm light from an optical parametric amplifier. The simple fiber structure offers shallow dispersion and flat transmission in the near and mid-infrared, enabling the generation of broadband spectra extending from 270 nm to 3.1 µm, with a total energy of a few µJ. In addition, we demonstrate the emission of ultraviolet dispersive waves whose frequency can be tuned simply by adjusting the pump wavelength...
April 3, 2017: Optics Express
https://www.readbyqxmd.com/read/28376781/fatigue-strength-of-bovine-articular-cartilage-on-bone-under-three-point-bending-the-effect-of-loading-frequency
#15
H Sadeghi, D M Espino, D E T Shepherd
BACKGROUND: The objective of this study was to determine the influence of loading frequency on the failure of articular cartilage-on-bone specimens under three-point bending. METHODS: In this study, cyclic three-point bending was used to introduce failure into cartilage-on-bone specimens at varying loading frequencies. Sinusiodally varying maximum compressive loads in the range 40-130 N were applied to beam-shaped cartilage-on-bone specimens at frequencies of 1, 10, 50 and 100 Hz...
April 4, 2017: BMC Musculoskeletal Disorders
https://www.readbyqxmd.com/read/28375911/trigeminal-neuralgia
#16
Giorgio Cruccu
PURPOSE OF REVIEW: Although trigeminal neuralgia is well known to neurologists, recent developments in classification and clinical diagnosis, new MRI methods, and a debate about surgical options necessitate an update on the topic. RECENT FINDINGS: Currently, a worldwide controversy exists regarding the classification, diagnostic process, and surgical treatment of trigeminal neuralgia. This controversy has been caused on one side by the recognition that some 50% of patients with trigeminal neuralgia, apart from characteristic paroxysmal attacks, also have continuous pain in the same territory, which results in greater diagnostic difficulties and is associated with a lower response to medical and surgical treatments...
April 2017: Continuum: Lifelong Learning in Neurology
https://www.readbyqxmd.com/read/28375165/power-mosfet-linearizer-of-a-high-voltage-power-amplifier-for-high-frequency-pulse-echo-instrumentation
#17
Hojong Choi, Park Chul Woo, Jung-Yeol Yeom, Changhan Yoon
A power MOSFET linearizer is proposed for a high-voltage power amplifier (HVPA) used in high-frequency pulse-echo instrumentation. The power MOSFET linearizer is composed of a DC bias-controlled series power MOSFET shunt with parallel inductors and capacitors. The proposed scheme is designed to improve the gain deviation characteristics of the HVPA at higher input powers. By controlling the MOSFET bias voltage in the linearizer, the gain reduction into the HVPA was compensated, thereby reducing the echo harmonic distortion components generated by the ultrasonic transducers...
April 4, 2017: Sensors
https://www.readbyqxmd.com/read/28374944/reliability-of-eustachian-tube-function-measurements-in-a-hypobaric-and-hyperbaric-pressure-chamber
#18
Moritz F Meyer, Stefanie Jansen, Oxana Mordkovich, Karl-Bernd Hüttenbrink, Dirk Beutner
OBJECTIVES: Measurement of the Eustachian tube (ET) function is a challenge. The demand for a precise and meaningful diagnostic tool increases - especially since more and more operative therapies are being offered without objective evidence. The measurement of the ET function by continuous impedance recording in a pressure chamber is an established method, although the reliability of the measurements is still unclear. METHODS: 25 participants (50 ears) were exposed to phases of compression and decompression in a hypo and hyperbaric pressure chamber...
April 4, 2017: Clinical Otolaryngology
https://www.readbyqxmd.com/read/28372084/compressive-sensing-based-spherical-harmonics-decomposition-of-a-low-frequency-sound-field-within-a-cylindrical-cavity
#19
Yan Wang, Kean Chen
A low frequency sound field within a cylindrical cavity can be well approximated by a sparse set of Fourier-Bessel series in a spherical coordinate system. The approximation accuracy can be guaranteed as long as the series coefficients are well estimated by use of spherical microphone arrays (SMA). Conventional methods like spherical Fourier transform and Helmholtz equation least square require a large number of sensors, and it is difficult to estimate the high order coefficients in the presence of sensor noise...
March 2017: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/28371778/analysis-of-packet-loss-induced-distortion-in-view-synthesis-prediction-based-3d-video-coding
#20
Pan Gao, Qiang Peng, Wei Xiang
View synthesis prediction (VSP) is a crucial coding tool for improving compression efficiency in the next generation 3D video systems. However, VSP is susceptible to catastrophic error propagation when multi-view video plus depth (MVD) data are transmitted over lossy networks. This paper aims at accurately modeling the transmission errors propagated in the inter-view direction caused by VSP. Toward this end, we first study how channel errors gradually propagate along the VSP-based inter-view prediction path...
June 2017: IEEE Transactions on Image Processing: a Publication of the IEEE Signal Processing Society
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