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Clinical Neurophysiology Practice 2019Vestibular evoked myogenic potentials (VEMPs) are a useful and increasingly popular component of the neuro-otology test battery. These otolith-dependent reflexes are... (Review)
Review
Vestibular evoked myogenic potentials (VEMPs) are a useful and increasingly popular component of the neuro-otology test battery. These otolith-dependent reflexes are produced by stimulating the ears with air-conducted sound or skull vibration and recorded from surface electrodes placed over the neck (cervical VEMPs) and eye muscles (ocular VEMPs). VEMP abnormalities have been reported in various diseases of the ear and vestibular system, and VEMPs have a clear role in the diagnosis of superior semicircular canal dehiscence. However there is significant variability in the methods used to stimulate the otoliths and record the reflexes. This review discusses VEMP methodology and provides a detailed theoretical background for the techniques that are typically used. The review also outlines the common pitfalls in VEMP recording and the clinical applications of VEMPs.
PubMed: 30949613
DOI: 10.1016/j.cnp.2019.01.005 -
Proceedings of the VLDB Endowment.... May 2016As scientific endeavors and data analysis become increasingly collaborative, there is a need for data management systems that natively support the or of datasets to...
As scientific endeavors and data analysis become increasingly collaborative, there is a need for data management systems that natively support the or of datasets to enable concurrent analysis, cleaning, integration, manipulation, or curation of data across teams of individuals. Common practice for sharing and collaborating on datasets involves creating or storing multiple copies of the dataset, one for each stage of analysis, with no provenance information tracking the relationships between these datasets. This results not only in wasted storage, but also makes it challenging to track and integrate modifications made by different users to the same dataset. In this paper, we introduce the Relational Dataset Branching System, Decibel, a new relational storage system with built-in version control designed to address these shortcomings. We present our initial design for Decibel and provide a thorough evaluation of three versioned storage engine designs that focus on efficient query processing with minimal storage overhead. We also develop an exhaustive benchmark to enable the rigorous testing of these and future versioned storage engine designs.
PubMed: 28149668
DOI: 10.14778/2947618.2947619 -
JAMA Otolaryngology-- Head & Neck... May 2023
Topics: Humans; Noise; Audiometry
PubMed: 36892831
DOI: 10.1001/jamaoto.2023.0035 -
Ophthalmology Feb 1990
Topics: Calibration; Electroretinography; Light; Photic Stimulation; Retinal Vein Occlusion
PubMed: 2360950
DOI: 10.1016/s0161-6420(90)32597-6 -
The Journal of the Acoustical Society... Sep 2015The mean sound exposure level from a source is routinely estimated by the mean of the observed sound exposures from repeated measurements. A formula for the standard...
The mean sound exposure level from a source is routinely estimated by the mean of the observed sound exposures from repeated measurements. A formula for the standard uncertainty based on the Guide to the expression of Uncertainty in Measurement (GUM) is derived. An alternative formula is derived for the case where the GUM method fails. The formulas are applied on several examples, and compared with a Monte Carlo calculation of the standard uncertainty. The recommended formula can be seen simply as a convenient translation of the uncertainty on an energy scale into the decibel level scale, but with a theoretical foundation.
PubMed: 26428824
DOI: 10.1121/1.4929619 -
The Journal of Laryngology and Otology Apr 1950
Topics: Hearing; Hearing Tests; Humans; Prednisone; Sound
PubMed: 15412304
DOI: 10.1017/s0022215100011919 -
Journal of Clinical Nursing Sep 2010The study was designed to determine daytime decibel levels on the hospital's four medical/surgical nursing units, daytime decibel levels in patient rooms in...
AIMS AND OBJECTIVES
The study was designed to determine daytime decibel levels on the hospital's four medical/surgical nursing units, daytime decibel levels in patient rooms in corresponding nursing units, whether the nursing unit noise levels differed and to identify what generated noise on those units.
BACKGROUND
Nurses are responsible for components of patients' physical environments, particularly those that promote patient safety and well-being. Numerous studies have linked hospital noise to negative physiological outcomes for both patients and staff. However, decisions related to managing patient acoustic environments continue to rely on nursing judgment, rather than objective evidence.
DESIGN
Non-human subject, observational/descriptive design.
METHOD
Using noise dosimeters, weekday day shift decibel levels were measured on four nursing units, sequentially. Measures were made continuously over 12 hours, in three patient rooms and over five minutes every 45 minutes, at the corresponding nurses' station. Noise generators were documented at the nurses' station.
RESULTS
Nursing units had average measured sound levels of 62·2, 63·3, 61·7 and 64·6 decibels, respectively, and were not significantly different from one another (p = 0·07). Nurses' designation of 'quiet', 'typical' and 'noisy' patient rooms was not consistently confirmed by the measured decibel levels. The range of minimum to maximum decibel levels was significantly greater in patient rooms than the nurses' station (54·4 versus 27·7 decibels, p < 0·01), and on average, more than 12 noise generators were identified during any one-five-minute study period.
CONCLUSIONS
Patient care areas in today's hospitals are as noisy as a busy office. Nursing judgment is not sufficient to make informed decisions directed towards controlling inpatients' acoustic environment. Standards applied across studies to measure and characterise acoustic environments are urgently needed.
RELEVANCE TO CLINICAL PRACTICE
Objective measures, not nursing judgment alone, are required to assess acoustic environments and to direct interventions that improve them.
Topics: Humans; Noise, Occupational; Nursing Staff, Hospital; Occupational Exposure; Surgery Department, Hospital
PubMed: 20920074
DOI: 10.1111/j.1365-2702.2010.03263.x -
Optics Express Sep 2019The availability of low-loss optical interfaces to couple light between standard optical fibers and high-index-contrast silicon waveguides is essential for the...
The availability of low-loss optical interfaces to couple light between standard optical fibers and high-index-contrast silicon waveguides is essential for the development of chip-integrated nanophotonics. Input and output couplers based on diffraction gratings are attractive coupling solutions. Advanced grating coupler designs, with Bragg or metal mirror underneath, low- and high-index overlays, and multi-level or multi-layer layouts, have proven less useful due to customized or complex fabrication, however. In this work, we propose a rather simpler in design of efficient off-chip fiber couplers that provide a simulated efficiency up to 95% (-0.25 dB) at a wavelength of 1.55 µm. These grating couplers are formed with an L-shaped waveguide profile and synthesized subwavelength grating metamaterials. This concept jointly provides sufficient degrees of freedom to simultaneously control the grating directionality and out-radiated field profile of the grating mode. The proposed chip-to-fiber couplers promote robust sub-decibel coupling of light, yet contain device dimensions (> 120 nm) compatible with standard lithographic technologies presently available in silicon nanophotonic foundries. Fabrication imperfections are also investigated. Dimensional offsets of ± 15 nm in shallow-etch depth and ± 10 nm in linewidth's and mask misalignments are tolerated for a 1-dB loss penalty. The proposed concept is meant to be universal, which is an essential prerequisite for developing reliable and low-cost optical couplers. We foresee that the work on L-shaped grating couplers with sub-decibel coupling efficiencies could also be a valuable direction for silicon chip interfacing in integrated nanophotonics.
PubMed: 31510482
DOI: 10.1364/OE.27.026239 -
The Journal of Laryngology and Otology Nov 1993Decibel scales are a very important but potentially confusing subject for the clinician. Misunderstanding can, at worst, lead to inappropriate management which is...
Decibel scales are a very important but potentially confusing subject for the clinician. Misunderstanding can, at worst, lead to inappropriate management which is detrimental to the patient. This paper sets out, from the viewpoint of an acoustician, the calibration and meaning of the various decibel scales in common use, shows how they are applied to the clinical setting, and explains their limitations.
Topics: Audiology; Audiometry; Auditory Perception; Calibration; Hearing; Humans; Sensation; Sound; Weights and Measures
PubMed: 8288991
DOI: 10.1017/s002221510012506x -
Reproductive Toxicology (Elmsford, N.Y.) Oct 2019Maternal stress may affect the fetal auditory system than direct sound exposure. The objective of this study was to evaluate the role of prenatal stress due to...
Maternal stress may affect the fetal auditory system than direct sound exposure. The objective of this study was to evaluate the role of prenatal stress due to high-decibel (dB) sound exposure on postnatal hearing and cochlear structure. Pregnant rats were exposed to 95 or 65 dB noise or music for 2 h once a day from gestational day 15 until delivery. The serum corticosterone was measured in the pregnant dams and pups. On postnatal day 22, pups underwent auditory brainstem response (ABR) testing. Then, the cochleae were immediately harvested for biochemical and molecular investigations. Prenatal stress impaired reproductive parameters, increased serum corticosterone and ABR thresholds with the decrease in wave I peak amplitude and the number of pre-synaptic ribbon. Thus, prenatal stress induces postnatal hearing loss in young rats, which are related to the reduction of ribbon synapses.
Topics: Acoustic Stimulation; Animals; Auditory Threshold; Cochlea; Corticosterone; Evoked Potentials, Auditory, Brain Stem; Female; Hearing Disorders; Male; Maternal Exposure; Noise; Pregnancy; Prenatal Exposure Delayed Effects; Rats, Sprague-Dawley; Stress, Psychological; Synapses
PubMed: 31238098
DOI: 10.1016/j.reprotox.2019.05.067