11 research outputs found
Distribution characteristics of air-bone gaps : evidence of bias in manual audiometry
OBJECTIVES : Five databases were mined to examine distributions of airbone
gaps obtained by automated and manual audiometry. Differences
in distribution characteristics were examined for evidence of influences
unrelated to the audibility of test signals.
DESIGN : The databases provided air- and bone-conduction thresholds
that permitted examination of air-bone gap distributions that were free
of ceiling and floor effects. Cases with conductive hearing loss were
eliminated based on air-bone gaps, tympanometry, and otoscopy, when
available. The analysis is based on 2,378,921 threshold determinations
from 721,831 subjects from five databases.
RESULTS : Automated audiometry produced air-bone gaps that were normally
distributed suggesting that air- and bone-conduction thresholds
are normally distributed. Manual audiometry produced air-bone gaps
that were not normally distributed and show evidence of biasing effects
of assumptions of expected results. In one database, the form of the
distributions showed evidence of inclusion of conductive hearing losses.
CONCLUSIONS : Thresholds obtained by manual audiometry show tester
bias effects from assumptions of the patient’s hearing loss characteristics.
Tester bias artificially reduces the variance of bone-conduction
thresholds and the resulting air-bone gaps. Because the automated
method is free of bias from assumptions of expected results, these distributions
are hypothesized to reflect the true variability of air- and boneconduction
thresholds and the resulting air-bone gaps.Portions of this work were supported by Grant RC3DC010986 from the
National Institute of Deafness and Other Communication Disorders and
by contract No. VA118-12-C-0029 from the US Department of Veterans
Affairs. The Rehabilitation Research and Development Service of the US
Department of Veterans Affairs supported this work through the Auditory
and Vestibular Dysfunction Research Enhancement Award Program
(REAP) and a Senior Research Career Scientist award to the second author.http://journals.lww.com/ear-hearing2017-03-31hb2016Speech-Language Pathology and Audiolog
Comprehensive measures of sound exposures in cinemas using smart phones
OBJECTIVES
Sensorineural hearing loss from sound overexposure has a considerable prevalence. Identification of sound hazards is crucial, as prevention, due to a lack of definitive therapies, is the sole alternative to hearing aids. One subjectively loud, yet little studied, potential sound hazard is movie theaters. This study uses smart phones to evaluate their applicability as a widely available, validated sound pressure level (SPL) meter. Therefore, this study measures sound levels in movie theaters to determine whether sound levels exceed safe occupational noise exposure limits and whether sound levels in movie theaters differ as a function of movie, movie theater, presentation time, and seat location within the theater.
DESIGN
Six smart phones with an SPL meter software application were calibrated with a precision SPL meter and validated as an SPL meter. Additionally, three different smart phone generations were measured in comparison to an integrating SPL meter. Two different movies, an action movie and a children's movie, were measured six times each in 10 different venues (n = 117). To maximize representativeness, movies were selected focusing on large release productions with probable high attendance. Movie theaters were selected in the San Francisco, CA, area based on whether they screened both chosen movies and to represent the largest variety of theater proprietors. Measurements were analyzed in regard to differences between theaters, location within the theater, movie, as well as presentation time and day as indirect indicator of film attendance.
RESULTS
The smart phone measurements demonstrated high accuracy and reliability. Overall, sound levels in movie theaters do not exceed safe exposure limits by occupational standards. Sound levels vary significantly across theaters and demonstrated statistically significant higher sound levels and exposures in the action movie compared to the children's movie. Sound levels decrease with distance from the screen. However, no influence on time of day or day of the week as indirect indicator of film attendance could be found.
CONCLUSIONS
Calibrated smart phones with an appropriate software application as used in this study can be utilized as a validated SPL meter. Because of the wide availability, smart phones in combination with the software application can provide high quantity recreational sound exposure measurements, which can facilitate the identification of potential noise hazards. Sound levels in movie theaters decrease with distance to the screen, but do not exceed safe occupational noise exposure limits. Additionally, there are significant differences in sound levels across movie theaters and movies, but not in presentation time
Anatomic measures of upper airway structures in obstructive sleep apnea
Objective: Determine if anatomic dimensions of airway structures are associated with airway obstruction in obstructive sleep apnea (OSA) patients. Methods: Twenty-eight subjects with (n = 14) and without (n = 14) OSA as determined by clinical symptoms and sleep studies; volunteer sample. Skeletal and soft tissue dimensions were measured from radiocephalometry and magnetic resonance imaging. The soft palate thickness, mandibular plane-hyoid (MP-H) distance, posterior airway space (PAS) diameters and area, and tongue volume were calculated. Results: Compared to controls, the OSA group demonstrated a significantly longer MP-H distance (P = 0.009) and shorter nasal PAS diameter (P = 0.02). The PAS area was smaller (P = 0.002) and tongue volume larger in the OSA group (P = 0.004). The MP-H distance, PAS measurements, and tongue volume are of clinical relevance in OSA patients. Conclusions: A long MP-H distance, and small PAS diameters and area are significant anatomic measures in OSA; however the most substantial parameter found was a large tongue volume. Keywords: Obstructive sleep apnea, Anatomy, Anatomic measurement, Posterior airway space, Tongue volume, Hyoid positio
Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)
In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field