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Noise induced

Ishan S Bhatt, O'neil Guthrie
OBJECTIVE: Bilateral audiometric notch (BN) at 4000-6000 Hz was identified as a noise-induced hearing loss (NIHL) phenotype for genetic association analysis in college-aged musicians. This study analysed BN in a sample of US youth. DESIGN: Prevalence of the BN within the study sample was determined and logistic-regression analyses were performed to identify audiologic and other demographic factors associated with BN. Computer-simulated "flat" audiograms were used to estimate potential influence of false-positive rates in estimating the prevalence of the BN...
February 8, 2017: International Journal of Audiology
Susie Vrobel
This paper focusses on the notions of time and timelessness in Eastern and Western thought traditions. The Introduction addresses the Eastern differentiation between the mind, which does not operate in a successive manner and is therefore not caught in time, and the time-laden successively operating mind and brain. I also describe how Jiddu Krishnamurti reconciles the two through insight, an event which restructures the brain and culminates in an eternal Now. In the following sections, I draw analogies to Western notions of timelessness and insight...
June 17, 2017: Progress in Biophysics and Molecular Biology
Zhe Wu, Hongjian He, Yi Sun, Yiping Du, Jianhui Zhong
Quantitative myelin water imaging (MWI) from signal T2* decay acquired with multiple Gradient-Recalled Echo (mGRE) sequence has been widely used since its first report. A recent study showed that with low resolution data (2mm isotropic voxels), direct application of complex fitting to a three-pool WM model with frequency shift terms could produce more stable parameter estimation for myelin water fraction mapping. MWI maps of higher spatial resolution resulting in more detailed tissue structures and reduced partial volume effects around white matter/gray matter (WM/GM) interface, however, is more desirable...
June 16, 2017: Magnetic Resonance Imaging
Makoto Tanaka, Yoshitaka Hashimoto, Chihiro Hasegawa, Steve Deacon, Richard Eastell
BACKGROUND: ONO-5334 is a cathepsin K inhibitor that induced bone mineral density (BMD) gain in a phase II study in postmenopausal osteoporosis patients. Even though the antiresorptive effect could only be monitored in the morning during the study, simulation can allow the antiresorptive effect to be assessed over 24 h, with assessment of the relationship to BMD gain. METHODS: Inhibition of the serum C-telopeptide of type I collagen (sCTX) level at doses of ONO-5334 of 100 mg once daily (QD), 300 mg QD, and 50 mg twice daily (BID) was simulated using plasma ONO-5334 pharmacokinetic (PK) data for repeated dose administration in a phase I study and corresponding sCTX inhibition from the PK-pharmacodynamic (PK/PD) relationship...
June 19, 2017: BMC Musculoskeletal Disorders
Hongbin Chen, Bin Zheng, Chao Liang, Li Zhao, Ying Zhang, Huizhuo Pan, Wanying Ji, Xiaoqun Gong, Hanjie Wang, Jin Chang
The photothermal therapy agents induced by 808 nm near infrared light laser have good potential for photothermal therapy (PTT) in vivo, with the advantages of harmless treatment, minimally invasion, high efficiency and deep tissue penetration. For the traditional photothermal therapy agents, however, it was impossible to track them in vivo because of the low signal-to-noise ratio, so we cannot conduct the extra near infrared light laser to radiate tumors sites accurately. Herein, we introduce a new complex: indocyanine green (ICG), near-infrared persistent luminescence (PL) phosphors ZnGa2O4:Cr(3+) (ZGC) and mesoporous silica nanoparticles (MSNs) (ICG@mZGC nanoparticles) were assembled for long-lasting optical imaging to guide PTT...
October 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
Pedro Oliveira, Goncalo Martins Pereira, Margarida Seara Simões, Emanuel Monteiro, António Pedro Alves de Matos, Artur Águas, José Martins Dos Santos
INTRODUCTION: Low-frequency noise (LFN) is a ubiquitous physical stressor known to cause degenerative cellular changes and organ alterations with functional repercussions both in humans and animals. MATERIALS AND METHODS: After acceptance of the study protocol by a local ethics committee, 20 Wistar rats were randomly divided into two equal groups. One group was kept in silence and the other continuously exposed to LFN during 13 weeks. The rats had unlimited access to water and were fed standard rat chow...
June 19, 2017: Ultrastructural Pathology
Jun Wu, Weiju Han, Xingrui Chen, Weiwei Guo, Ke Liu, Ruoya Wang, Jishuai Zhang, Na Sai
The cochlear blood-labyrinth barrier (BLB), located in the stria vascularis, is critical for the homeostasis of cochlear solutes and ion transport. Significant disruption to the BLB occurs early during noise‑induced hearing loss. Matrix metalloproteinase (MMP)‑2 and ‑9 are important molecules known to be capable of degrading tight junction (TJ) proteins. The TJ proteins are important components of the extracellular matrix (ECM), required to maintain BLB integrity and permeability. Previous studies have demonstrated that MMP‑2 and ‑9, rich in healthy cochlea, serve an essential role in regulating the cochlear response to acoustic trauma...
June 15, 2017: Molecular Medicine Reports
Xunnong Xu, Thomas Purdy, Jacob M Taylor
Optomechanical systems show tremendous promise for the high-sensitivity sensing of forces and modification of mechanical properties via light. For example, similar to neutral atoms and trapped ions, laser cooling of mechanical motion by radiation pressure can take single mechanical modes to their ground state. Conventional optomechanical cooling is able to introduce an additional damping channel to mechanical motion while keeping its thermal noise at the same level, and, as a consequence, the effective temperature of the mechanical mode is lowered...
June 2, 2017: Physical Review Letters
Kiyoshi Wesley Masui, Ue-Li Pen, Neil Turok
We show that three-dimensional information is critical to discerning the effects of parity violation in the primordial gravity-wave background. If present, helical gravity waves induce parity-violating correlations in the cosmic microwave background (CMB) between parity-odd polarization B modes and parity-even temperature anisotropies (T) or polarization E modes. Unfortunately, EB correlations are much weaker than would be naively expected, which we show is due to an approximate symmetry resulting from the two-dimensional nature of the CMB...
June 2, 2017: Physical Review Letters
Jyh-Yang Wang, Tao-Hsiang Chung, Teik-Hui Lee, Chii-Dong Chen
We investigate theoretically and experimentally the environment-induced voltage shot noise in current biased Josephson junctions induced by phase particle tunneling. Quantum mechanical treatment based on the Caldeira-Leggett model with tight-binding formulation in local Wannier bases gives a clear picture of the voltage shot noise. A universal form of the zero-frequency noise spectrum is obtained, which exhibits a quadratic dependence on the mean voltage in small bias region. The quadratic dependence is verified experimentally on junctions covering a wide range of parameters, and is found also in junction arrays of various array sizes...
June 15, 2017: Scientific Reports
Daniel A Hagen, Francisco J Valero-Cuevas
We investigated how kinematic redundancy interacts with the neurophysiological control mechanisms required for smooth and accurate, rapid limb movements. Biomechanically speaking, tendon excursions are over-determined because the rotation of few joints determines the lengths and velocities of many muscles. But how different are the muscle velocity profiles induced by various, equally valid hand trajectories? We used an 18-muscle sagittal-plane arm model to calculate 100,000 feasible shoulder, elbow, and wrist joint rotations that produced valid basketball free throws with different hand trajectories, but identical initial and final hand positions and velocities...
May 31, 2017: Journal of Biomechanics
Xu Wang, Xiaonan Wang, Wuzhou Yu, Zaixiu Jiang, Dongxing Mao
When sound barriers are installed on both sides of a noise source, degradation in performance is observed. Barriers having negative-phase-gradient surfaces successfully eliminate this drawback by trapping sound energy in between the barriers. In contrast, barriers can also be designed to "dredge" the energy flux out. An extended model considering higher-order diffractions, which resulted from the interplay of the induced surface wave and barrier surface periodicity, is presented. It is found that the sound dredging barriers provide a remarkable enhancement over the trapping ones, and hence have the potential to be widely used in noise control engineering...
June 2017: Journal of the Acoustical Society of America
Jason Hindes, Ira B Schwartz
We study the extinction of long-lived epidemics on finite complex networks induced by intrinsic noise. Applying analytical techniques to the stochastic susceptible-infected-susceptible model, we predict the distribution of large fluctuations, the most probable or optimal path through a network that leads to a disease-free state from an endemic state, and the average extinction time in general configurations. Our predictions agree with Monte Carlo simulations on several networks, including synthetic weighted and degree-distributed networks with degree correlations, and an empirical high school contact network...
May 2017: Physical Review. E
I Sagert, W P Even, T T Strother
We perform two-dimensional implosion simulations using a Monte Carlo kinetic particle code. The application of a kinetic transport code is motivated, in part, by the occurrence of nonequilibrium effects in inertial confinement fusion capsule implosions, which cannot be fully captured by hydrodynamic simulations. Kinetic methods, on the other hand, are able to describe both continuum and rarefied flows. We perform simple two-dimensional disk implosion simulations using one-particle species and compare the results to simulations with the hydrodynamics code rage...
May 2017: Physical Review. E
Paul Ritchie, Jan Sieber
We propose an approximation for the probability of tipping when the speed of parameter change and additive white noise interact to cause tipping. Our approximation is valid for small to moderate drift speeds and helps to estimate the probability of false positives and false negatives in early-warning indicators in the case of rate- and noise-induced tipping. We illustrate our approximation on a prototypical model for rate-induced tipping with additive noise using Monte Carlo simulations. The formula can be extended to close encounters of rate-induced tipping and is otherwise applicable to other forms of tipping...
May 2017: Physical Review. E
Vladimir V Semenov
The model of a double-well oscillator with nonlinear dissipation is studied. The self-sustained oscillation regime and the excitable one are described. The first regime consists of the coexistence of two stable limit cycles in the phase space, which correspond to self-sustained oscillations of the point mass in either potential well. The self-sustained oscillations do not occur in a noise-free system in the excitable regime, but appropriate conditions for coherence resonance in either potential well can be achieved...
May 2017: Physical Review. E
Emanuel N van den Broeke, Bart de Vries, Julien Lambert, Diana M Torta, André Mouraux
OBJECTIVE: Pinprick-evoked brain potentials (PEPs) have been proposed as a technique to investigate secondary hyperalgesia and central sensitization in humans. However, the signal-to-noise (SNR) of PEPs is low. Here, using time-frequency analysis, we characterize the phase-locked and non-phase-locked EEG responses to pinprick stimulation, before and after secondary hyperalgesia. METHODS: Secondary hyperalgesia was induced using high-frequency electrical stimulation (HFS) of the left/right forearm skin in 16 volunteers...
May 19, 2017: Clinical Neurophysiology: Official Journal of the International Federation of Clinical Neurophysiology
Satoshi Ii, Mohd Azrul Hisham Mohd Adib, Yoshiyuki Watanabe, Shigeo Wada
This paper presents a novel data assimilation method for patient-specific blood flow analysis based on feedback control theory called the physically consistent feedback control-based data assimilation (PFC-DA) method. In the PFC-DA method, the signal, which is the residual error term of the velocity when comparing the numerical and reference measurement data, is cast as a source term in a Poisson equation for the scalar potential field that induces flow in a closed system. The pressure values at the inlet and outlet boundaries are recursively calculated by this scalar potential field...
June 15, 2017: International Journal for Numerical Methods in Biomedical Engineering
Tetiana Dadakova, Axel Joachim Krafft, Ali Caglar Özen, Michael Bock
PURPOSE: Optimization of timing parameters for MR-guided ARFI to achieve the highest displacement signal-to-noise ratio (SNRd ). THEORY AND METHODS: In MR-guided ARFI the phase change induced by motion encoding gradients (MEGs) is measured to assess tissue displacement. The sensitivity of this encoding procedure depends on several timing parameters, such as the MEG duration and the offset time between ultrasound (US) and MEG. Furthermore, mechanical and MR tissue constants and MEG schemes (bipolar or three-lobed) influence SNRd ...
June 15, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Steinar Engen, Bernt-Erik Sæther
Evolutionary adaptations following environmental deterioration can sometimes rescue populations from extinction. Here we provide a scenario in which such evolutionary rescue will be difficult. Using a rather general model for fluctuating r- and K-selection in a density-dependent population, we show that reduction of available resources will not necessarily induce evolution of adaptations to counteract such changes provided that density regulation acts through available resources per individual. In large populations, resource depletion may induce a change in stationary distribution of population size while the optimal phenotype remains unchanged...
July 2017: American Naturalist
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