Characterization of structural and electrical properties of ZnO tetrapods

Science.gov (United States)

Gu, Yu-Dong; Mai, Wen-Jie; Jiang, Peng

2011-12-01

ZnO tetrapods were synthesized by a typical thermal vapor-solid deposition method in a horizontal tube furnace. Structural characterization was carried out by transmission electron microscopy (TEM) and select-area electron diffraction (SAED), which shows the presence of zinc blende nucleus in the center of tetrapods while the four branches taking hexagonal wurtzite structure. The electrical transport property of ZnO tetrapods was investigated through an in-situ nanoprobe system. The three branches of a tetrapod serve as source, drain, and "gate", respectively; while the fourth branch pointing upward works as the force trigger by vertically applying external force downward. The conductivity of each branch of ZnO-tetrapods increases 3-4 times under pressure. In such situation, the electrical current through the branches of ZnO tetrapods can be tuned by external force, and therefore a simple force sensor based on ZnO tetrapods has been demonstrated for the first time.

Ventastega curonica and the origin of tetrapod morphology.

Science.gov (United States)

Ahlberg, Per E; Clack, Jennifer A; Luksevics, Ervīns; Blom, Henning; Zupiņs, Ivars

2008-06-26

The gap in our understanding of the evolutionary transition from fish to tetrapod is beginning to close thanks to the discovery of new intermediate forms such as Tiktaalik roseae. Here we narrow it further by presenting the skull, exceptionally preserved braincase, shoulder girdle and partial pelvis of Ventastega curonica from the Late Devonian of Latvia, a transitional intermediate form between the 'elpistostegids' Panderichthys and Tiktaalik and the Devonian tetrapods (limbed vertebrates) Acanthostega and Ichthyostega. Ventastega is the most primitive Devonian tetrapod represented by extensive remains, and casts light on a part of the phylogeny otherwise only represented by fragmentary taxa: it illuminates the origin of principal tetrapod structures and the extent of morphological diversity among the transitional forms.

Trophic convergence drives morphological convergence in marine tetrapods.

Science.gov (United States)

Kelley, Neil P; Motani, Ryosuke

2015-01-01

Marine tetrapod clades (e.g. seals, whales) independently adapted to marine life through the Mesozoic and Caenozoic, and provide iconic examples of convergent evolution. Apparent morphological convergence is often explained as the result of adaptation to similar ecological niches. However, quantitative tests of this hypothesis are uncommon. We use dietary data to classify the feeding ecology of extant marine tetrapods and identify patterns in skull and tooth morphology that discriminate trophic groups across clades. Mapping these patterns onto phylogeny reveals coordinated evolutionary shifts in diet and morphology in different marine tetrapod lineages. Similarities in morphology between species with similar diets-even across large phylogenetic distances-are consistent with previous hypotheses that shared functional constraints drive convergent evolution in marine tetrapods.

The axial skeleton of the Devonian tetrapod Ichthyostega.

Science.gov (United States)

Ahlberg, Per Erik; Clack, Jennifer A; Blom, Henning

2005-09-01

Ichthyostega was the first Devonian tetrapod to be subject to a whole-body reconstruction. It remains, together with Acanthostega, one of only two Devonian tetrapods for which near-complete postcranial material is available. It is thus crucially important for our understanding of the earliest stages of tetrapod evolution and terrestrialization. Here we show a new reconstruction of Ichthyostega based on extensive re-examination of original material and augmented by recently collected specimens. Our reconstruction differs substantially from those previously published and reveals hitherto unrecognized regionalization in the vertebral column. Ichthyostega is the earliest vertebrate to show obvious adaptations for non-swimming locomotion. Uniquely among early tetrapods, the presacral vertebral column shows pronounced regionalization of neural arch morphology, suggesting that it was adapted for dorsoventral rather than lateral flexion.

Hearing sensitivity in context: Conservation implications for a highly vocal endangered species

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Megan A. Owen

2016-04-01

Full Text Available Hearing sensitivity is a fundamental determinant of a species’ vulnerability to anthropogenic noise, however little is known about the hearing capacities of most conservation dependent species. When audiometric data are integrated with other aspects of species’ acoustic ecology, life history, and characteristic habitat topography and soundscape, predictions can be made regarding probable vulnerability to the negative impacts of different types of anthropogenic noise. Here we used an adaptive psychoacoustic technique to measure hearing thresholds in the endangered giant panda; a species that uses acoustic communication to coordinate reproduction. Our results suggest that giant pandas have functional hearing into the ultrasonic range, with good sensitivity between 10.0 and 16.0 kHz, and best sensitivity measured at 12.5–14.0 kHz. We estimated the lower and upper limits of functional hearing as 0.10 and 70.0 kHz respectively. While these results suggest that panda hearing is similar to that of some other terrestrial carnivores, panda hearing thresholds above 14.0 kHz were significantly lower (i.e., more sensitive than those of the polar bear, the only other bear species for which data are available. We discuss the implications of this divergence, as well as the relationship between hearing sensitivity and the spectral parameters of panda vocalizations. We suggest that these data, placed in context, can be used towards the development of a sensory-based model of noise disturbance for the species.

Changes in Hearing Sensitivity Following Portable Stereo System Use.

Science.gov (United States)

Pugsley, S; Stuart, A; Kalinowski, J; Armson, J

1993-11-01

Changes in hearing sensitivity following portable stereo system (PSS; Sony Walkman Model WM-AF605 with Sony Semiaural Headphones Model MDR-A21L) use were investigated. Test-retest differences (TRDs) in audiometric thresholds at eight frequencies (250, 500, 1000, 2000, 3000, 4000, 6000, & 8000 Hz) were obtained from 15 young adults before and after one hour of PSS exposure at their preferred listening levels.Values for the 95% confidence levels representing critical differences in test-retest auditory thresholds for the eight test frequencies were generated from a control group of 15 young adults. Experimental subjects' TRDs, when compared to the critical TRDs, failed to display a decrease in hearing sensitivity after one hour of PSS use. It is suggested that PSS use at preferred listening levels, following an exposure time of one hour, may not contribute to a significant impairment in hearing sensitivity.

Hearing with an atympanic ear: good vibration and poor sound-pressure detection in the royal python, Python regius.

Science.gov (United States)

Christensen, Christian Bech; Christensen-Dalsgaard, Jakob; Brandt, Christian; Madsen, Peter Teglberg

2012-01-15

Snakes lack both an outer ear and a tympanic middle ear, which in most tetrapods provide impedance matching between the air and inner ear fluids and hence improve pressure hearing in air. Snakes would therefore be expected to have very poor pressure hearing and generally be insensitive to airborne sound, whereas the connection of the middle ear bone to the jaw bones in snakes should confer acute sensitivity to substrate vibrations. Some studies have nevertheless claimed that snakes are quite sensitive to both vibration and sound pressure. Here we test the two hypotheses that: (1) snakes are sensitive to sound pressure and (2) snakes are sensitive to vibrations, but cannot hear the sound pressure per se. Vibration and sound-pressure sensitivities were quantified by measuring brainstem evoked potentials in 11 royal pythons, Python regius. Vibrograms and audiograms showed greatest sensitivity at low frequencies of 80-160 Hz, with sensitivities of -54 dB re. 1 m s(-2) and 78 dB re. 20 μPa, respectively. To investigate whether pythons detect sound pressure or sound-induced head vibrations, we measured the sound-induced head vibrations in three dimensions when snakes were exposed to sound pressure at threshold levels. In general, head vibrations induced by threshold-level sound pressure were equal to or greater than those induced by threshold-level vibrations, and therefore sound-pressure sensitivity can be explained by sound-induced head vibration. From this we conclude that pythons, and possibly all snakes, lost effective pressure hearing with the complete reduction of a functional outer and middle ear, but have an acute vibration sensitivity that may be used for communication and detection of predators and prey.

Zinc oxide tetrapods as efficient photocatalysts for organic pollutant degradation

Science.gov (United States)

Liu, Fangzhou; Leung, Yu Hang; Djurisić, Aleksandra B.; Liao, Changzhong; Shih, Kaimin

2014-03-01

Bisphenol A (BPA) and other organic pollutants from industrial wastewater have drawn increasing concern in the past decades regarding their environmental and biological risks, and hence developing strategies of effective degradation of BPA and other organic pollutants is imperative. Metal oxide nanostructures, in particular titanium oxide (TiO2) and zinc oxide (ZnO), have been demonstrated to exhibit efficient photodegradation of various common organic dyes. ZnO tetrapods are of special interest due to their low density of native defects which consequently lead to lower recombination losses and higher photocatalytic efficiency. Tetrapods can be obtained by relatively simple and low-cost vapor phase deposition in large quantity; the micron-scale size would also be advantageous for catalyst recovery. In this study, the photodegradation of BPA with ZnO tetrapods and TiO2 nanostructures under UV illumination were compared. The concentration of BPA dissolved in DI water was analyzed by high-performance liquid chromatography (HPLC) at specified time intervals. It was observed that the photocatalytic efficiency of ZnO tetrapods eventually surpassed Degussa P25 in free-standing form, and more than 80% of BPA was degraded after 60 min. Photodegradation of other organic dye pollutants by tetrapods and P25 were also examined. The superior photocatalytic efficiency of ZnO tetrapods for degradation of BPA and other organic dye pollutants and its correlation with the material properties were discussed.

Contrasting developmental trajectories in the earliest known tetrapod forelimbs.

Science.gov (United States)

Callier, Viviane; Clack, Jennifer A; Ahlberg, Per E

2009-04-17

Ichthyostega and Acanthostega are the earliest tetrapods known from multiple near-complete skeletons, with Acanthostega generally considered the more primitive. New material indicates differing ontogenetic trajectories for their forelimbs: In Ichthyostega, the pattern of muscle attachment processes on small humeri (upper arm bones) resembles that in "fish" members of the tetrapod stem group such as Tiktaalik, whereas large humeri approach (but fail to attain) the tetrapod crown-group condition; in Acanthostega, both small and large humeri exhibit the crown-group pattern. We infer that Ichthyostega underwent greater locomotory terrestrialization during ontogeny. The newly recognized primitive characteristics also suggest that Ichthyostega could be phylogenetically more basal than Acanthostega.

Early tetrapod relationships revisited.

Science.gov (United States)

Ruta, Marcello; Coates, Michael I; Quicke, Donald L J

2003-05-01

In an attempt to investigate differences between the most widely discussed hypotheses of early tetrapod relationships, we assembled a new data matrix including 90 taxa coded for 319 cranial and postcranial characters. We have incorporated, where possible, original observations of numerous taxa spread throughout the major tetrapod clades. A stem-based (total-group) definition of Tetrapoda is preferred over apomorphy- and node-based (crown-group) definitions. This definition is operational, since it is based on a formal character analysis. A PAUP* search using a recently implemented version of the parsimony ratchet method yields 64 shortest trees. Differences between these trees concern: (1) the internal relationships of aïstopods, the three selected species of which form a trichotomy; (2) the internal relationships of embolomeres, with Archeria crassidisca and Pholiderpeton scut collapsed in a trichotomy with a clade formed by Anthracosaurus russelli and Pholiderpeton attheyi; (3) the internal relationships of derived dissorophoids, with four amphibamid species forming an unresolved node with a clade consisting of micromelerpetontids and branchiosaurids and a clade consisting of albanerpetontids plus basal crown-group lissamphibians; (4) the position of albenerpetontids and Eocaecilia micropoda, which form an unresolved node with a trichotomy subtending Karaurus sharovi, Valdotriton gracilis and Triadobatrachus massinoti; (5) the branching pattern of derived diplocaulid nectrideans, with Batrachiderpeton reticulatum and Diceratosaurus brevirostris collapsed in a trichotomy with a clade formed by Diplocaulus magnicornis and Diploceraspis burkei. The results of the original parsimony run--as well as those retrieved from several other treatments of the data set (e.g. exclusion of postcranial and lower jaw data; character reweighting; reverse weighting)--indicate a deep split of early tetrapods between lissamphibian- and amniote-related taxa. Colosteids, Crassigyrinus

Ventastega curonica and the origin of tetrapod morphology

OpenAIRE

Ahlberg, Per; Clack, Jennifer; Luksevics, Ervins; Blom, Henning; Zupins, Ivars

2008-01-01

The gap in our understanding of the evolutionary transition from fish to tetrapod is beginning to close thanks to the discovery of new intermediate forms such as Tiktaalik roseae. Here we narrow it further by presenting the skull, exceptionally preserved braincase, shoulder girdle and partial pelvis of Ventastega curonica from the Late Devonian of Latvia, a transitional intermediate form between the 'elpistostegids' Panderichthys and Tiktaalik and the Devonian tetrapods (limbed vertebrates) A...

The relationship of speech intelligibility with hearing sensitivity, cognition, and perceived hearing difficulties varies for different speech perception tests

Science.gov (United States)

Heinrich, Antje; Henshaw, Helen; Ferguson, Melanie A.

2015-01-01

Listeners vary in their ability to understand speech in noisy environments. Hearing sensitivity, as measured by pure-tone audiometry, can only partly explain these results, and cognition has emerged as another key concept. Although cognition relates to speech perception, the exact nature of the relationship remains to be fully understood. This study investigates how different aspects of cognition, particularly working memory and attention, relate to speech intelligibility for various tests. Perceptual accuracy of speech perception represents just one aspect of functioning in a listening environment. Activity and participation limits imposed by hearing loss, in addition to the demands of a listening environment, are also important and may be better captured by self-report questionnaires. Understanding how speech perception relates to self-reported aspects of listening forms the second focus of the study. Forty-four listeners aged between 50 and 74 years with mild sensorineural hearing loss were tested on speech perception tests differing in complexity from low (phoneme discrimination in quiet), to medium (digit triplet perception in speech-shaped noise) to high (sentence perception in modulated noise); cognitive tests of attention, memory, and non-verbal intelligence quotient; and self-report questionnaires of general health-related and hearing-specific quality of life. Hearing sensitivity and cognition related to intelligibility differently depending on the speech test: neither was important for phoneme discrimination, hearing sensitivity alone was important for digit triplet perception, and hearing and cognition together played a role in sentence perception. Self-reported aspects of auditory functioning were correlated with speech intelligibility to different degrees, with digit triplets in noise showing the richest pattern. The results suggest that intelligibility tests can vary in their auditory and cognitive demands and their sensitivity to the challenges that

The evolution of locomotor rhythmicity in tetrapods.

Science.gov (United States)

Ross, Callum F; Blob, Richard W; Carrier, David R; Daley, Monica A; Deban, Stephen M; Demes, Brigitte; Gripper, Janaya L; Iriarte-Diaz, Jose; Kilbourne, Brandon M; Landberg, Tobias; Polk, John D; Schilling, Nadja; Vanhooydonck, Bieke

2013-04-01

Differences in rhythmicity (relative variance in cycle period) among mammal, fish, and lizard feeding systems have been hypothesized to be associated with differences in their sensorimotor control systems. We tested this hypothesis by examining whether the locomotion of tachymetabolic tetrapods (birds and mammals) is more rhythmic than that of bradymetabolic tetrapods (lizards, alligators, turtles, salamanders). Species averages of intraindividual coefficients of variation in cycle period were compared while controlling for gait and substrate. Variance in locomotor cycle periods is significantly lower in tachymetabolic than in bradymetabolic animals for datasets that include treadmill locomotion, non-treadmill locomotion, or both. When phylogenetic relationships are taken into account the pooled analyses remain significant, whereas the non-treadmill and the treadmill analyses become nonsignificant. The co-occurrence of relatively high rhythmicity in both feeding and locomotor systems of tachymetabolic tetrapods suggests that the anatomical substrate of rhythmicity is in the motor control system, not in the musculoskeletal components. © 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.

The Westphalian tetrapod fauna; some aspects of its geography and ecology

Energy Technology Data Exchange (ETDEWEB)

Milner, A.R.

1987-05-01

Fossil tetrapods (amphibians and reptiles) have been found in Westphalian Series beds at over 40 localities, seven of which have produced assemblages with a diversity of six or more genera. All tetrapod-bearing assemblages derive from the southern lowlands of Euramerica which correspond to the Westphalian equatorial belt. The preservational environments and the eight major tetrapod groups of the Westphalian are briefly reviewed and apparent associations are identified. There appear to be four overlapping tetrapod associations which may correspond to four communities, namely: (I) terrestrial, (II) lowland open water body (fresh water or brackish), (III) lowland restricted water body (fresh water or brackish), and (IV) intermontane basin restricted water body (fresh water). Factors which may determine the nature of the preserved assemblages include marine influence, openness of water-body and seasonal variation. 84 refs., 4 figs.

Realization and field emission of CdSe nano-tetrapods with different arm lengths

Energy Technology Data Exchange (ETDEWEB)

Zhao Lijuan, E-mail: ljzhao@dhu.edu.c [Applied Physics Department, Donghua University, Shanghai 201620 (China); Physics Department and the Institute of Nano-Science and Technology, Hong Kong University of Science and Technology, Clear Water Bay (Hong Kong); Pang Qi [Physics Department and the Institute of Nano-Science and Technology, Hong Kong University of Science and Technology, Clear Water Bay (Hong Kong); Yang Shihe [Chemistry Department and the Institute of Nano-Science and Technology, Hong Kong University of Science and Technology, Clear Water Bay (Hong Kong); Ge Weikun; Wang Jiannong [Physics Department and the Institute of Nano-Science and Technology, Hong Kong University of Science and Technology, Clear Water Bay (Hong Kong)

2009-08-10

The arms of CdSe nano-tetrapods can be greatly elongated with the core diameters and arm width unchanged by multiple injections. Room-temperature absorption and photoluminescence (PL) spectra of tetrapods with different arm lengths show that these tetrapods have almost the same core size, which is consistent with the high resolution TEM results. Field emission characteristics show that the onset field required drawing a current density of approx0.1 muAcm{sup -2} from CdSe nano-tetrapods with different arm lengths are 22 Vmum{sup -1}, 9 Vmum{sup -1}, and 4 Vmum{sup -1}, respectively, and the field enhancement factors are determined to be about 218, 554, and 946, respectively. Results show that the longer is the arm of the tetrapods, the lower the turn-on field and the higher the field enhancement factor.

Realization and field emission of CdSe nano-tetrapods with different arm lengths

International Nuclear Information System (INIS)

Zhao Lijuan; Pang Qi; Yang Shihe; Ge Weikun; Wang Jiannong

2009-01-01

The arms of CdSe nano-tetrapods can be greatly elongated with the core diameters and arm width unchanged by multiple injections. Room-temperature absorption and photoluminescence (PL) spectra of tetrapods with different arm lengths show that these tetrapods have almost the same core size, which is consistent with the high resolution TEM results. Field emission characteristics show that the onset field required drawing a current density of ∼0.1 μAcm -2 from CdSe nano-tetrapods with different arm lengths are 22 Vμm -1 , 9 Vμm -1 , and 4 Vμm -1 , respectively, and the field enhancement factors are determined to be about 218, 554, and 946, respectively. Results show that the longer is the arm of the tetrapods, the lower the turn-on field and the higher the field enhancement factor.

The relationship of speech intelligibility with hearing sensitivity, cognition, and perceived hearing difficulties varies for different speech perception tests

Directory of Open Access Journals (Sweden)

Antje eHeinrich

2015-06-01

Full Text Available Listeners vary in their ability to understand speech in noisy environments. Hearing sensitivity, as measured by pure-tone audiometry, can only partly explain these results, and cognition has emerged as another key concept. Although cognition relates to speech perception, the exact nature of the relationship remains to be fully understood. This study investigates how different aspects of cognition, particularly working memory and attention, relate to speech intelligibility for various tests.Perceptual accuracy of speech perception represents just one aspect of functioning in a listening environment. Activity and participation limits imposed by hearing loss, in addition to the demands of a listening environment, are also important and may be better captured by self-report questionnaires. Understanding how speech perception relates to self-reported aspects of listening forms the second focus of the study.Forty-four listeners aged between 50-74 years with mild SNHL were tested on speech perception tests differing in complexity from low (phoneme discrimination in quiet, to medium (digit triplet perception in speech-shaped noise to high (sentence perception in modulated noise; cognitive tests of attention, memory, and nonverbal IQ; and self-report questionnaires of general health-related and hearing-specific quality of life.Hearing sensitivity and cognition related to intelligibility differently depending on the speech test: neither was important for phoneme discrimination, hearing sensitivity alone was important for digit triplet perception, and hearing and cognition together played a role in sentence perception. Self-reported aspects of auditory functioning were correlated with speech intelligibility to different degrees, with digit triplets in noise showing the richest pattern. The results suggest that intelligibility tests can vary in their auditory and cognitive demands and their sensitivity to the challenges that auditory environments pose on

Oldest pathology in a tetrapod bone illuminates the origin of terrestrial vertebrates.

Directory of Open Access Journals (Sweden)

Peter J Bishop

Full Text Available The origin of terrestrial tetrapods was a key event in vertebrate evolution, yet how and when it occurred remains obscure, due to scarce fossil evidence. Here, we show that the study of palaeopathologies, such as broken and healed bones, can help elucidate poorly understood behavioural transitions such as this. Using high-resolution finite element analysis, we demonstrate that the oldest known broken tetrapod bone, a radius of the primitive stem tetrapod Ossinodus pueri from the mid-Viséan (333 million years ago of Australia, fractured under a high-force, impact-type loading scenario. The nature of the fracture suggests that it most plausibly occurred during a fall on land. Augmenting this are new osteological observations, including a preferred directionality to the trabecular architecture of cancellous bone. Together, these results suggest that Ossinodus, one of the first large (>2m length tetrapods, spent a significant proportion of its life on land. Our findings have important implications for understanding the temporal, biogeographical and physiological contexts under which terrestriality in vertebrates evolved. They push the date for the origin of terrestrial tetrapods further back into the Carboniferous by at least two million years. Moreover, they raise the possibility that terrestriality in vertebrates first evolved in large tetrapods in Gondwana rather than in small European forms, warranting a re-evaluation of this important evolutionary event.

Enhanced performance of hybrid solar cells using longer arms of quantum cadmium selenide tetrapods

KAUST Repository

Lee, Kyu-Sung

2011-12-01

We demonstrate that enhanced device performance of hybrid solar cells based on tetrapod (TP)-shaped cadmium selenide (CdSe) nanoparticles and conjugated polymer of poly (3-hexylthiophene) (P3HT) can be obtained by using longer armed tetrapods which aids in better spatial connectivity, thus decreasing charge hopping events which lead to better charge transport. Longer tetrapods with 10 nm arm length lead to improved power conversion efficiency of 1.12% compared to 0.80% of device having 5 nm short-armed tetrapods:P3HT photoactive blends.

Enhanced performance of hybrid solar cells using longer arms of quantum cadmium selenide tetrapods

KAUST Repository

Lee, Kyu-Sung; Kim, Inho; Gullapalli, Sravani; Wong, Michael S.; Jabbour, Ghassan E.

2011-01-01

We demonstrate that enhanced device performance of hybrid solar cells based on tetrapod (TP)-shaped cadmium selenide (CdSe) nanoparticles and conjugated polymer of poly (3-hexylthiophene) (P3HT) can be obtained by using longer armed tetrapods which aids in better spatial connectivity, thus decreasing charge hopping events which lead to better charge transport. Longer tetrapods with 10 nm arm length lead to improved power conversion efficiency of 1.12% compared to 0.80% of device having 5 nm short-armed tetrapods:P3HT photoactive blends.

Aberration corrected and 3D cryo-tomography HAADF-STEM surface studies of ZnO tetrapods

International Nuclear Information System (INIS)

Ward, M R; Gai, P L; Boyes, E D; Sugiura, H; Tanaka, N; Yoshida, K

2012-01-01

We present a morphology study of ZnO tetrapods using aberration corrected TEM, HAADF-STEM and 3D HAADF-STEM cryotomography as an alternative to more conventional TEM and SEM techniques. We use 3D IMOD reconstructions to show that the {11-bar 0} facets dominate the total surface area of uniform hexagonal prism tetrapods. Using HRTEM we show that the small tetrapods have a zincblende phase core from which the four legs extend. The facets and the edges of these legs were found to be atomically clean and flat with the potential for ZnO tetrapods as model substrates. We deposited ultrafine Pt/Pd nanoparticles onto the tetrapods and investigated the resulting morphologies. We found using HAADF-STEM cryotomography and reconstruction techniques that the nanoparticle coverage gave separate nanoparticles and overall uniform coverage. We believe these techniques and the results from them could be useful for the development of nanoparticle-ZnO tetrapod composite systems with applications in optoelectronics, gas sensing and catalysis.

Functionalized tetrapod-like ZnO nanostructures for plasmid DNA purification, polymerase chain reaction and delivery

International Nuclear Information System (INIS)

Nie Leng; Gao Lizeng; Yan Xiyun; Wang Taihong

2007-01-01

Functionalized tetrapodal ZnO nanostructures are tested in plasmid DNA experiments (1) as a solid-phase adsorbent for plasmid DNA purification (2) as improving reagents in a polymerase chain reaction (PCR) and (3) as novel carriers for gene delivery. The amino-modification, the tetrapod-like shape of the nanostructure and its high biocompatibility all contribute to measurements showing promise for applications. A sol-gel method is used for silica coating and amino-modification. Plasmid DNA is purified through reversible conjugations of amino-modified ZnO tetrapods with DNA. Also, as additional reagents, functionalized tetrapods are shown to improve the amount of PCR product. For transfection, ZnO tetrapods provide some protection against deoxyribonuclease cleavage of plasmid DNA and deliver plasmid DNA into cells with little cytotoxicity

The evolution of tetrapod ears and the fossil record.

Science.gov (United States)

Clack, J A

1997-01-01

In the earliest tetrapods, the fenestra vestibuli was a large hole in the braincase wall bounded by bones of different embryological origins: the otic capsule and occipital arch components, and also, in all except the Devonian Acanthostega, the dermal parasphenoid. This means that the hole lay along the line of the embryonic metotic fissure. Early tetrapod braincases were poorly ossified internally, and no specialized opening for a perilymphatic duct is evident. It is arguable that the earliest tetrapods had neither a perilympllatic duct crossing the otic capsule nor a specialized auditory receptor in a separate lagenar pouch. The primitive tetrapod condition is found in the earliest amniotes, and the separate development of (1) a fenestra vestibuli confined to the limits of the otic capsule, (2) a specialized pressure relief window also derived from components on the line of the metolic fissure, (3) a nonstructural, vibratory stapes and (4) increased internal ossification of the internal walls of the otic capsule, can be traced separately in synapsids, lepidosauromorph diapsids, archosauromorph diapsids, probably turtles, and amphibians. This suggests separate development of true tympanic ears in each of these groups. Developments indicating the existence of a true tympanic ear in amniotes are first found in animals from the Triassic period, and a correlation with the evolution of insect sound production is suggested.

Near-Stasis in the Long-Term Diversification of Mesozoic Tetrapods

Science.gov (United States)

Benson, Roger B. J.; Butler, Richard J.; Alroy, John; Mannion, Philip D.; Carrano, Matthew T.; Lloyd, Graeme T.

2016-01-01

How did evolution generate the extraordinary diversity of vertebrates on land? Zero species are known prior to ~380 million years ago, and more than 30,000 are present today. An expansionist model suggests this was achieved by large and unbounded increases, leading to substantially greater diversity in the present than at any time in the geological past. This model contrasts starkly with empirical support for constrained diversification in marine animals, suggesting different macroevolutionary processes on land and in the sea. We quantify patterns of vertebrate standing diversity on land during the Mesozoic–early Paleogene interval, applying sample-standardization to a global fossil dataset containing 27,260 occurrences of 4,898 non-marine tetrapod species. Our results show a highly stable pattern of Mesozoic tetrapod diversity at regional and local levels, underpinned by a weakly positive, but near-zero, long-term net diversification rate over 190 million years. Species diversity of non-flying terrestrial tetrapods less than doubled over this interval, despite the origins of exceptionally diverse extant groups within mammals, squamates, amphibians, and dinosaurs. Therefore, although speciose groups of modern tetrapods have Mesozoic origins, rates of Mesozoic diversification inferred from the fossil record are slow compared to those inferred from molecular phylogenies. If high speciation rates did occur in the Mesozoic, then they seem to have been balanced by extinctions among older clades. An apparent 4-fold expansion of species richness after the Cretaceous/Paleogene (K/Pg) boundary deserves further examination in light of potential taxonomic biases, but is consistent with the hypothesis that global environmental disturbances such as mass extinction events can rapidly adjust limits to diversity by restructuring ecosystems, and suggests that the gradualistic evolutionary diversification of tetrapods was punctuated by brief but dramatic episodes of radiation

The pelvic fin and girdle of Panderichthys and the origin of tetrapod locomotion.

Science.gov (United States)

Boisvert, Catherine A

2005-12-22

One of the most marked transformations in the vertebrate transition to land was that of fins to limbs. This transformation involved not only the generation of morphological novelties (digits, sacrum) but also a shift in locomotory dominance from the pectoral to the pelvic appendage. Despite its importance, the transformation from pelvic fin to hindlimb is the least studied and least well-documented part of this transformation, which is bracketed by the osteolepiform Eusthenopteron and the early tetrapods Ichthyostega and Acanthostega, but is not directly illuminated by any intermediate form. Panderichthys is the closest tetrapod relative currently represented by complete fossils, but its pelvic fin skeleton has not been described. Here, I present the only known articulated pelvic fin endoskeleton and associated partial pelvis of Panderichthys. The pelvic girdle is even less tetrapod-like than that of the osteolepiform Eusthenopteron, but the pelvic fin endoskeleton shares derived characteristics with basal tetrapods despite being more primitive than the pectoral fin of Panderichthys. The evolution of tetrapod locomotion appears to have passed through a stage of body-flexion propulsion, in which the pelvic fins played a relatively minor anchoring part, before the emergence of hindlimb-powered propulsion in the interval between Panderichthys and Acanthostega.

Feeding biomechanics in Acanthostega and across the fish-tetrapod transition.

Science.gov (United States)

Neenan, James M; Ruta, Marcello; Clack, Jennifer A; Rayfield, Emily J

2014-04-22

Acanthostega is one of the earliest and most primitive limbed vertebrates. Its numerous fish-like features indicate a primarily aquatic lifestyle, yet cranial suture morphology suggests that its skull is more similar to those of terrestrial taxa. Here, we apply geometric morphometrics and two-dimensional finite-element analysis to the lower jaws of Acanthostega and 22 other tetrapodomorph taxa in order to quantify morphological and functional changes across the fish-tetrapod transition. The jaw of Acanthostega is similar to that of certain tetrapodomorph fish and transitional Devonian taxa both morphologically (as indicated by its proximity to those taxa in morphospace) and functionally (as indicated by the distribution of stress values and relative magnitude of bite force). Our results suggest a slow tempo of morphological and biomechanical changes in the transition from Devonian tetrapod jaws to aquatic/semi-aquatic Carboniferous tetrapod jaws. We conclude that Acanthostega retained a primitively aquatic lifestyle and did not possess cranial adaptations for terrestrial feeding.

Feeding biomechanics in Acanthostega and across the fish–tetrapod transition

Science.gov (United States)

Neenan, James M.; Ruta, Marcello; Clack, Jennifer A.; Rayfield, Emily J.

2014-01-01

Acanthostega is one of the earliest and most primitive limbed vertebrates. Its numerous fish-like features indicate a primarily aquatic lifestyle, yet cranial suture morphology suggests that its skull is more similar to those of terrestrial taxa. Here, we apply geometric morphometrics and two-dimensional finite-element analysis to the lower jaws of Acanthostega and 22 other tetrapodomorph taxa in order to quantify morphological and functional changes across the fish–tetrapod transition. The jaw of Acanthostega is similar to that of certain tetrapodomorph fish and transitional Devonian taxa both morphologically (as indicated by its proximity to those taxa in morphospace) and functionally (as indicated by the distribution of stress values and relative magnitude of bite force). Our results suggest a slow tempo of morphological and biomechanical changes in the transition from Devonian tetrapod jaws to aquatic/semi-aquatic Carboniferous tetrapod jaws. We conclude that Acanthostega retained a primitively aquatic lifestyle and did not possess cranial adaptations for terrestrial feeding. PMID:24573844

Envelope enhancement increases cortical sensitivity to interaural envelope delays with acoustic and electric hearing.

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Douglas E H Hartley

Full Text Available Evidence from human psychophysical and animal electrophysiological studies suggests that sensitivity to interaural time delay (ITD in the modulating envelope of a high-frequency carrier can be enhanced using half-wave rectified stimuli. Recent evidence has shown potential benefits of equivalent electrical stimuli to deaf individuals with bilateral cochlear implants (CIs. In the current study we assessed the effects of envelope shape on ITD sensitivity in the primary auditory cortex of normal-hearing ferrets, and profoundly-deaf animals with bilateral CIs. In normal-hearing animals, cortical sensitivity to ITDs (±1 ms in 0.1-ms steps was assessed in response to dichotically-presented i sinusoidal amplitude-modulated (SAM and ii half-wave rectified (HWR tones (100-ms duration; 70 dB SPL presented at the best-frequency of the unit over a range of modulation frequencies. In separate experiments, adult ferrets were deafened with neomycin administration and bilaterally-implanted with intra-cochlear electrode arrays. Electrically-evoked auditory brainstem responses (EABRs were recorded in response to bipolar electrical stimulation of the apical pair of electrodes with singe biphasic current pulses (40 µs per phase over a range of current levels to measure hearing thresholds. Subsequently, we recorded cortical sensitivity to ITDs (±800 µs in 80-µs steps within the envelope of SAM and HWR biphasic-pulse trains (40 µs per phase; 6000 pulses per second, 100-ms duration over a range of modulation frequencies. In normal-hearing animals, nearly a third of cortical neurons were sensitive to envelope-ITDs in response to SAM tones. In deaf animals with bilateral CI, the proportion of ITD-sensitive cortical neurons was approximately a fifth in response to SAM pulse trains. In normal-hearing and deaf animals with bilateral CI the proportion of ITD sensitive units and neural sensitivity to ITDs increased in response to HWR, compared with SAM stimuli

Middle-Upper Triassic and Middle Jurassic tetrapod track assemblages of southern Tunisia, Sahara Platform

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Niedźwiedzki, Grzegorz; Soussi, Mohamed; Boukhalfa, Kamel; Gierliński, Gerard D.

2017-05-01

Three tetrapod track assemblages from the early-middle Mesozoic of southern Tunisia are reported. The strata exposed at the Tejra 2 clay-pit near the Medenine and Rehach site, located in the vicinity of Kirchaou, contain the first tetrapod tracks found in the Triassic of Tunisia. The Middle Jurassic (early Aalenian) dinosaur tracks are reported from the Mestaoua plain near Tataouine. In the Middle Triassic outcrop of the Tejra 2 clay-pit, tridactyl tracks of small and medium-sized dinosauromorphs, were discovered. These tracks represent the oldest evidence of dinosaur-lineage elements in the Triassic deposits of Tunisia. Similar tracks have been described from the Middle Triassic of Argentina, France and Morocco. An isolated set of the manus and pes of a quadrupedal tetrapod discovered in Late Triassic Rehach tracksite is referred to a therapsid tracemaker. The Middle Jurassic deposits of the Mestaoua plain reveal small and large tridactyl theropod dinosaur tracks (Theropoda track indet. A-C). Based on comparison with the abundant record of Triassic tetrapod ichnofossils from Europe and North America, the ichnofauna described here indicates the presence of a therapsid-dinosauromorph ichnoassociation (without typical Chirotheriidae tracks) in the Middle and Late Triassic, which sheds light on the dispersal of the Middle-Upper Triassic tetrapod ichnofaunas in this part of Gondwana. The reported Middle Jurassic ichnofauna show close similarities to dinosaur track assemblages from the Lower and Middle Jurassic of northwestern Africa, North America, Europe and also southeastern Asia. Sedimentological and lithostratigraphic data of each new tracksite have been defined on published data and new observations. Taken together, these discoveries present a tantalizing window into the evolutionary history of tetrapods from the Triassic and Jurassic of southern Tunisia. Given the limited early Mesozoic tetrapod record from the region, these discoveries are of both temporal and

Sequences, stratigraphy and scenarios: what can we say about the fossil record of the earliest tetrapods?

Science.gov (United States)

Friedman, Matt; Brazeau, Martin D

2011-02-07

Past research on the emergence of digit-bearing tetrapods has led to the widely accepted premise that this important evolutionary event occurred during the Late Devonian. The discovery of convincing digit-bearing tetrapod trackways of early Middle Devonian age in Poland has upset this orthodoxy, indicating that current scenarios which link the timing of the origin of digited tetrapods to specific events in Earth history are likely to be in error. Inspired by this find, we examine the fossil record of early digit-bearing tetrapods and their closest fish-like relatives from a statistical standpoint. We find that the Polish trackways force a substantial reconsideration of the nature of the early tetrapod record when only body fossils are considered. However, the effect is less drastic (and often not statistically significant) when other reliably dated trackways that were previously considered anachronistic are taken into account. Using two approaches, we find that 95 per cent credible and confidence intervals for the origin of digit-bearing tetrapods extend into the Early Devonian and beyond, spanning late Emsian to mid Ludlow. For biologically realistic diversity models, estimated genus-level preservation rates for Devonian digited tetrapods and their relatives range from 0.025 to 0.073 per lineage-million years, an order of magnitude lower than species-level rates for groups typically considered to have dense records. Available fossils of early digited tetrapods and their immediate relatives are adequate for documenting large-scale patterns of character acquisition associated with the origin of terrestriality, but low preservation rates coupled with clear geographical and stratigraphic sampling biases caution against building scenarios for the origin of digits and terrestrialization tied to the provenance of particular specimens or faunas.

Reconstructing pectoral appendicular muscle anatomy in fossil fish and tetrapods over the fins-to-limbs transition.

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Molnar, Julia L; Diogo, Rui; Hutchinson, John R; Pierce, Stephanie E

2018-05-01

The question of how tetrapod limbs evolved from fins is one of the great puzzles of evolutionary biology. While palaeontologists, developmental biologists, and geneticists have made great strides in explaining the origin and early evolution of limb skeletal structures, that of the muscles remains largely unknown. The main reason is the lack of consensus about appendicular muscle homology between the closest living relatives of early tetrapods: lobe-finned fish and crown tetrapods. In the light of a recent study of these homologies, we re-examined osteological correlates of muscle attachment in the pectoral girdle, humerus, radius, and ulna of early tetrapods and their close relatives. Twenty-nine extinct and six extant sarcopterygians were included in a meta-analysis using information from the literature and from original specimens, when possible. We analysed these osteological correlates using parsimony-based character optimization in order to reconstruct muscle anatomy in ancestral lobe-finned fish, tetrapodomorph fish, stem tetrapods, and crown tetrapods. Our synthesis revealed that many tetrapod shoulder muscles probably were already present in tetrapodomorph fish, while most of the more-distal appendicular muscles either arose later from largely undifferentiated dorsal and ventral muscle masses or did not leave clear correlates of attachment in these taxa. Based on this review and meta-analysis, we postulate a stepwise sequence of specific appendicular muscle acquisitions, splits, and fusions that led from the ancestral sarcopterygian pectoral fin to the ancestral tetrapod forelimb. This sequence largely agrees with previous hypotheses based on palaeontological and comparative work, but it is much more comprehensive in terms of both muscles and taxa. Combined with existing information about the skeletal system, our new synthesis helps to illuminate the genetic, developmental, morphological, functional, and ecological changes that were key components of the

Extreme Modification of the Tetrapod Forelimb in a Triassic Diapsid Reptile.

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Pritchard, Adam C; Turner, Alan H; Irmis, Randall B; Nesbitt, Sterling J; Smith, Nathan D

2016-10-24

The tetrapod forelimb is one of the most versatile structures in vertebrate evolution, having been co-opted for an enormous array of functions. However, the structural relationships between the bones of the forelimb have remained largely unchanged throughout the 375 million year history of Tetrapoda, with a radius and ulna made up of elongate, paralleling shafts contacting a series of shorter carpal bones. These features are consistent across nearly all known tetrapods, suggesting that the morphospace encompassed by these taxa is limited by some sort of constraint(s). Here, we report on a series of three-dimensionally preserved fossils of the small-bodied (reptile Drepanosaurus, from the Chinle Formation of New Mexico, USA, which dramatically diverge from this pattern. Along with the crushed type specimen from Italy, these specimens have a flattened, crescent-shaped ulna with a long axis perpendicular to that of the radius and hyperelongate, shaft-like carpal bones contacting the ulna that are proximodistally longer than the radius. The second digit supports a massive, hooked claw. This condition has similarities to living "hook-and-pull" digging mammals and demonstrates that specialized, modern ecological roles had developed during the Triassic Period, over 200 million years ago. The forelimb bones in Drepanosaurus represent previously unknown morphologies for a tetrapod and, thus, a dramatic expansion of known tetrapod forelimb morphospace. Copyright © 2016 Elsevier Ltd. All rights reserved.

Life history of the stem tetrapod Acanthostega revealed by synchrotron microtomography.

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Sanchez, Sophie; Tafforeau, Paul; Clack, Jennifer A; Ahlberg, Per E

2016-09-15

The transition from fish to tetrapod was arguably the most radical series of adaptive shifts in vertebrate evolutionary history. Data are accumulating rapidly for most aspects of these events, but the life histories of the earliest tetrapods remain completely unknown, leaving a major gap in our understanding of these organisms as living animals. Symptomatic of this problem is the unspoken assumption that the largest known Devonian tetrapod fossils represent adult individuals. Here we present the first, to our knowledge, life history data for a Devonian tetrapod, from the Acanthostega mass-death deposit of Stensiö Bjerg, East Greenland. Using propagation phase-contrast synchrotron microtomography (PPC-SRμCT) to visualize the histology of humeri (upper arm bones) and infer their growth histories, we show that even the largest individuals from this deposit are juveniles. A long early juvenile stage with unossified limb bones, during which individuals grew to almost final size, was followed by a slow-growing late juvenile stage with ossified limbs that lasted for at least six years in some individuals. The late onset of limb ossification suggests that the juveniles were exclusively aquatic, and the predominance of juveniles in the sample suggests segregated distributions of juveniles and adults at least at certain times. The absolute size at which limb ossification began differs greatly between individuals, suggesting the possibility of sexual dimorphism, adaptive strategies or competition-related size variation.

Forelimb-hindlimb developmental timing changes across tetrapod phylogeny

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Selwood Lynne

2007-10-01

Full Text Available Abstract Background Tetrapods exhibit great diversity in limb structures among species and also between forelimbs and hindlimbs within species, diversity which frequently correlates with locomotor modes and life history. We aim to examine the potential relation of changes in developmental timing (heterochrony to the origin of limb morphological diversity in an explicit comparative and quantitative framework. In particular, we studied the relative time sequence of development of the forelimbs versus the hindlimbs in 138 embryos of 14 tetrapod species spanning a diverse taxonomic, ecomorphological and life-history breadth. Whole-mounts and histological sections were used to code the appearance of 10 developmental events comprising landmarks of development from the early bud stage to late chondrogenesis in the forelimb and the corresponding serial homologues in the hindlimb. Results An overall pattern of change across tetrapods can be discerned and appears to be relatively clade-specific. In the primitive condition, as seen in Chondrichthyes and Osteichthyes, the forelimb/pectoral fin develops earlier than the hindlimb/pelvic fin. This pattern is either retained or re-evolved in eulipotyphlan insectivores (= shrews, moles, hedgehogs, and solenodons and taken to its extreme in marsupials. Although exceptions are known, the two anurans we examined reversed the pattern and displayed a significant advance in hindlimb development. All other species examined, including a bat with its greatly enlarged forelimbs modified as wings in the adult, showed near synchrony in the development of the fore and hindlimbs. Conclusion Major heterochronic changes in early limb development and chondrogenesis were absent within major clades except Lissamphibia, and their presence across vertebrate phylogeny are not easily correlated with adaptive phenomena related to morphological differences in the adult fore- and hindlimbs. The apparently conservative nature of this

Terrestrial-style feeding in a very early aquatic tetrapod is supported by evidence from experimental analysis of suture morphology

OpenAIRE

Markey, Molly J.; Marshall, Charles R.

2007-01-01

There is no consensus on when in the fish-tetrapod transition suction feeding, the primary method of prey capture in the aquatic realm, evolved into the direct biting on prey typical of terrestrial animals. Here, we show that differences in the morphology of selected cranial sutures between species that span the fish–tetrapod transition (the Devonian osteolepiform fish Eusthenopteron, the aquatic Devonian tetrapod Acanthostega, and the Permian terrestrial tetrapod Phonerpeton) can be used to ...

Hearing sensitivity in context: Conservation implications for a highly vocal endangered species

OpenAIRE

Owen, Megan A.; Keating, Jennifer L.; Denes, Samuel K.; Hawk, Kathy; Fiore, Angela; Thatcher, Julie; Becerra, Jennifer; Hall, Suzanne; Swaisgood, Ronald R.

2016-01-01

Hearing sensitivity is a fundamental determinant of a species’ vulnerability to anthropogenic noise, however little is known about the hearing capacities of most conservation dependent species. When audiometric data are integrated with other aspects of species’ acoustic ecology, life history, and characteristic habitat topography and soundscape, predictions can be made regarding probable vulnerability to the negative impacts of different types of anthropogenic noise. Here we used an adaptive ...

On the Geological Age of the Sundyr Faunal Assemblage of Permian Tetrapods from the East European Platform

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Golubev V.K.

2015-03-01

Full Text Available A new Sundyr faunal assemblage of Permian tetrapods was discovered in Eastern Europe. It includes dinocephalians Titanosuchia fam. indet., tapinocephalians aff. Ulemosauridae, anomodontians aff. Suminia, therocephalians, gorgonopians Burnetioidea fam. indet., diapsids ? Eosuchia, chroniosuchians Suchonica vladimiri Golubev, enosuchids aff. Enosuchus, seymouriamorphs Microphon exiguus Ivachnenko and Leptoropha aff. talonophora, batrachomorphs Dvinosaurus sp. The Sundyr assemblage is a transitional one from the Isheevo to Sokolki assemblages. It is described as the last stage of evolution undergone by the dinocephalian community of tetrapods in Eastern Europe. Based on the bio- and magnetostratigraphic data, the beds with Sundyr tetrapod fauna pertain to the lower part of the Upper Severodvinian (= Putyatinian regional stage. These strata were distinguished into a new Suchonica vladimiri tetrapod assemblage zone. In the Sukhona River basin, the beds with Sundyr tetrapod fossils were distinguished into a new Ustpoldarsa Member of the Poldarsa Formation.

Efficient color-tunable multiexcitonic dual wavelength emission from Type II semiconductor tetrapods.

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Wu, Wen-Ya; Li, Mingjie; Lian, Jie; Wu, Xiangyang; Yeow, Edwin K L; Jhon, Mark H; Chan, Yinthai

2014-09-23

We synthesized colloidal InP/ZnS seeded CdS tetrapods by harnessing the structural stability of the InP/ZnS seed nanocrystals at the high reaction temperatures needed to grow the CdS arms. Because of an unexpected Type II band alignment at the interface of the InP/ZnS core and CdS arms that enhanced the occurrence of radiative excitonic recombination in CdS, these tetrapods were found to be capable of exhibiting highly efficient multiexcitonic dual wavelength emission of equal intensity at spectrally distinct wavelengths of ∼485 and ∼675 nm. Additionally, the Type II InP/ZnS seeded CdS tetrapods displayed a wider range of pump-dependent emission color-tunability (from red to white to blue) within the context of a CIE 1931 chromaticity diagram and possessed higher photostability due to suppressed multiexcitonic Auger recombination when compared to conventional Type I CdSe seeded CdS tetrapods. By employing time-resolved spectroscopy measurements, we were able to attribute the wide emission color-tunability to the large valence band offset between InP and CdS. This work highlights the importance of band alignment in the synthetic design of semiconductor nanoheterostructures, which can exhibit color-tunable multiwavelength emission with high efficiency and photostability.

Photoluminescence of colloidal CdSe nano-tetrapods and quantum dots in oxygenic and oxygen-free environments

Energy Technology Data Exchange (ETDEWEB)

Zhao, Lijuan [Donghua University, Applied Physics Department, Shanghai (China); Hong Kong University of Science and Technology, Physics Department and the Institute of Nano-Science and Technology, Hong Kong (China); Pang, Qi; Ge, Weikun; Wang, Jiannong [Hong Kong University of Science and Technology, Physics Department and the Institute of Nano-Science and Technology, Hong Kong (China); Yang, Shihe [Hong Kong University of Science and Technology, Chemistry Department and the Institute of Nano-Science and Technology, Hong Kong (China)

2011-05-15

The effects of oxygenic versus oxygen-free environments on colloidal CdSe nano-tetrapods and quantum dots (QDs) were studied using both continuous and time-resolved photoluminescence (PL) measurements. The decays of PL intensities for tetrapods and QDs in oxygen-free solution (chloroform) and in air (on silicon) can be well fitted by a bi-exponential function. Based on the emission-energy dependence of carrier lifetimes and the amplitude ratio of the fast-decay component to the slow-decay component, the fast and slow PL decays of CdSe nanocrystals are attributed to the recombination of delocalized carriers in the core states and localized carriers in the surface states, respectively. The PL intensities of CdSe nano-tetrapods and QDs were found to be five times and an order of magnitude higher in air than in vacuum, respectively, which is explained by the passivation of surface defects by the polar gas (oxygen) absorption. The lower enhancement in PL intensities of CdSe nano-tetrapods is explained by the special morphology of the tetrapods. (orig.)

Does the hearing sensitivity in thorny catfishes depend on swim bladder morphology?

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Angelika Zebedin

Full Text Available BACKGROUND: Thorny catfishes exhibit large variations in swim bladder morphology. These organs are of different sizes, forms and may have simple or branched diverticula. The swim bladder plays an important role in otophysans because it enhances their hearing sensitivity by transmitting sound pressure fluctuations via ossicles to the inner ear. METHODOLOGY/PRINCIPAL FINDINGS: To investigate if a form-function relationship exists, the swim bladder morphology and hearing ability were analyzed in six species. The morphology was quantified by measuring the length, width and height and calculating a standardized swim bladder length (sSBL, which was then used to calculate the relative swim bladder length (rSBL. Hearing was measured using the auditory evoked potential (AEP recording technique. Two species had simple apple-shaped and four species heart-shaped (cordiform bladders. One of the latter species had short unbranched diverticula on the terminal margin, two had a secondary bladder and two had many long, branched diverticula. The rSBL differed significantly between most of the species. All species were able to detect frequencies between 70 Hz and 6 kHz, with lowest thresholds found between 0.5 and 1 kHz (60 dB re 1 µPa. Hearing curves were U-shaped except in Hemidoras morrisi in which it was ramp-like. Mean hearing thresholds of species possessing smaller rSBLs were slightly lower (maximum 8.5 dB than those of species having larger rSBLs. CONCLUSIONS/SIGNIFICANCE: The current findings reveal a relationship between swim bladder form and its function among thorny catfishes. Relatively smaller swim bladders resulted in relatively better hearing. This is in contrast to a prior inter-familial study on catfishes in which species with large unpaired bladders possessed higher sensitivity at higher frequencies than species having tiny paired and encapsulated bladders.

Spiracular air breathing in polypterid fishes and its implications for aerial respiration in stem tetrapods

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Graham, Jeffrey B.; Wegner, Nicholas C.; Miller, Lauren A.; Jew, Corey J.; Lai, N. Chin; Berquist, Rachel M.; Frank, Lawrence R.; Long, John A.

2014-01-01

The polypterids (bichirs and ropefish) are extant basal actinopterygian (ray-finned) fishes that breathe air and share similarities with extant lobe-finned sarcopterygians (lungfishes and tetrapods) in lung structure. They are also similar to some fossil sarcopterygians, including stem tetrapods, in having large paired openings (spiracles) on top of their head. The role of spiracles in polypterid respiration has been unclear, with early reports suggesting that polypterids could inhale air through the spiracles, while later reports have largely dismissed such observations. Here we resolve the 100-year-old mystery by presenting structural, behavioural, video, kinematic and pressure data that show spiracle-mediated aspiration accounts for up to 93% of all air breaths in four species of Polypterus. Similarity in the size and position of polypterid spiracles with those of some stem tetrapods suggests that spiracular air breathing may have been an important respiratory strategy during the fish-tetrapod transition from water to land.

Late to the table: diversification of tetrapod mandibular biomechanics lagged behind the evolution of terrestriality.

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Anderson, Philip S L; Friedman, Matt; Ruta, Marcello

2013-08-01

The origin of digit-bearing tetrapods in the Middle to Late Devonian (ca. 393-360 Mya) and their subsequent invasion of land represent a classic case of a major evolutionary radiation driven by new ecological opportunities. In this and other examples, exploration of new eco-space is hypothesized to correlate with functional innovation and adaptive divergence of phenotypes. Simultaneous changes in all morphofunctional systems are rare in major evolutionary transitions and may be non-existent. Here, we focus on the mandibles of early tetrapods and their kin as a model system to test whether shifts in functional innovation were coeval with some major events in tetrapod history. To this end, we quantified mechanical variation in the mandibles of tetrapodomorphs ranging in age from Early Devonian to earliest Permian. Biomechanical disparity is stable from the Devonian to the Early Pennsylvanian, even though the origin of weight-bearing, digited limbs, and the initial phases of the colonization of land occurred during this interval. An appreciable increase in functional variation is detected in the latest Pennsylvanian and earliest Permian, when stem and crown amniotes began to explore new regions of mechanical morphospace, a pattern partly attributable to the origin of herbivory. We find no difference in the rate of functional change between tetrapodomorph "fish" and early digited tetrapods, although two independent shifts are detected among Devonian stem tetrapods more crownward than Acanthostega. Instead, the most profound shifts in evolutionary rate are nested well within the tetrapod crown and are associated with amniotes (particularly diadectomorphs and some synapsids). The substantial temporal gap between the origin of postcranial features associated with terrestriality, such as limbs with functional elbow/knee and wrist/ankle joints capable of weight-bearing, and the onset of divergence in jaw biomechanics provides a compelling example of "functional modularity

Experimental research on the stability of armour and secondary layer in a single layered Tetrapod breakwater

NARCIS (Netherlands)

De Jong, W.; Verhagen, H.J.; Olthof, J.

2004-01-01

Physical model tests were done on an armour of Tetrapods, placed in a single layer. The objective of the investigations was to study the stability of the secondary layer, and to see if the material of this secondary layer could be washed out through the single layer of Tetrapods. It was concluded

Deep-time evolution of regeneration and preaxial polarity in tetrapod limb development.

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Fröbisch, Nadia B; Bickelmann, Constanze; Olori, Jennifer C; Witzmann, Florian

2015-11-12

Among extant tetrapods, salamanders are unique in showing a reversed preaxial polarity in patterning of the skeletal elements of the limbs, and in displaying the highest capacity for regeneration, including full limb and tail regeneration. These features are particularly striking as tetrapod limb development has otherwise been shown to be a highly conserved process. It remains elusive whether the capacity to regenerate limbs in salamanders is mechanistically and evolutionarily linked to the aberrant pattern of limb development; both are features classically regarded as unique to urodeles. New molecular data suggest that salamander-specific orphan genes play a central role in limb regeneration and may also be involved in the preaxial patterning during limb development. Here we show that preaxial polarity in limb development was present in various groups of temnospondyl amphibians of the Carboniferous and Permian periods, including the dissorophoids Apateon and Micromelerpeton, as well as the stereospondylomorph Sclerocephalus. Limb regeneration has also been reported in Micromelerpeton, demonstrating that both features were already present together in antecedents of modern salamanders 290 million years ago. Furthermore, data from lepospondyl 'microsaurs' on the amniote stem indicate that these taxa may have shown some capacity for limb regeneration and were capable of tail regeneration, including re-patterning of the caudal vertebral column that is otherwise only seen in salamander tail regeneration. The data from fossils suggest that salamander-like regeneration is an ancient feature of tetrapods that was subsequently lost at least once in the lineage leading to amniotes. Salamanders are the only modern tetrapods that retained regenerative capacities as well as preaxial polarity in limb development.

Tetrapod tracks in Permo–Triassic eolian beds of southern Brazil (Paraná Basin

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Heitor Francischini

2018-05-01

Full Text Available Tetrapod tracks in eolianites are widespread in the fossil record since the late Paleozoic. Among these ichnofaunas, the ichnogenus Chelichnus is the most representative of the Permian tetrapod ichnological record of eolian deposits of Europe, North America and South America, where the Chelichnus Ichnofacies often occurs. In this contribution, we describe five sets of tracks (one of which is preserved in cross-section, representing the first occurrence of Dicynodontipus and Chelichnus in the “Pirambóia Formation” of southern Brazil. This unit represents a humid desert in southwestern Pangea and its lower and upper contacts lead us to consider its age as Lopingian–Induan. The five sets of tracks studied were compared with several ichnotaxa and body fossils with appendicular elements preserved, allowing us to attribute these tracks to dicynodonts and other indeterminate therapsids. Even though the “Pirambóia Formation” track record is sparse and sub-optimally preserved, it is an important key to better understand the occupation of arid environments by tetrapods across the Permo–Triassic boundary.

Optical properties of tetrapod nanostructured zinc oxide by chemical ...

African Journals Online (AJOL)

... deposited onto indium tin oxide (ITO) coated glass substrate by thermal chemical vapor deposition (TCVD) technique. This work studies the effects of annealing temperature ranging from 100–500 ºC towards its physical and optical properties. FESEM images showed that the structural properties of tetrapod nanostructured ...

Tempo and Mode of the Evolution of Venom and Poison in Tetrapods

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Richard J. Harris

2016-06-01

Full Text Available Toxic weaponry in the form of venom and poison has evolved in most groups of animals, including all four major lineages of tetrapods. Moreover, the evolution of such traits has been linked to several key aspects of the biology of toxic animals including life-history and diversification. Despite this, attempts to investigate the macroevolutionary patterns underlying such weaponry are lacking. In this study we analyse patterns of venom and poison evolution across reptiles, amphibians, mammals, and birds using a suite of phylogenetic comparative methods. We find that each major lineage has a characteristic pattern of trait evolution, but mammals and reptiles evolve under a surprisingly similar regime, whilst that of amphibians appears to be particularly distinct and highly contrasting compared to other groups. Our results also suggest that the mechanism of toxin acquisition may be an important distinction in such evolutionary patterns; the evolution of biosynthesis is far less dynamic than that of sequestration of toxins from the diet. Finally, contrary to the situation in amphibians, other tetrapod groups show an association between the evolution of toxic weaponry and higher diversification rates. Taken together, our study provides the first broad-scale analysis of macroevolutionary patterns of venom and poison throughout tetrapods.

The greatest step in vertebrate history: a paleobiological review of the fish-tetrapod transition.

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Long, John A; Gordon, Malcolm S

2004-01-01

Recent discoveries of previously unknown fossil forms have dramatically transformed understanding of many aspects of the fish-tetrapod transition. Newer paleobiological approaches have also contributed to changed views of which animals were involved and when, where, and how the transition occurred. This review summarizes major advances made and reevaluates alternative interpretations of important parts of the evidence. We begin with general issues and concepts, including limitations of the Paleozoic fossil record. We summarize important features of paleoclimates, paleoenvironments, paleobiogeography, and taphonomy. We then review the history of Devonian tetrapods and their closest stem group ancestors within the sarcopterygian fishes. It is now widely accepted that the first tetrapods arose from advanced tetrapodomorph stock (the elpistostegalids) in the Late Devonian, probably in Euramerica. However, truly terrestrial forms did not emerge until much later, in geographically far-flung regions, in the Lower Carboniferous. The complete transition occurred over about 25 million years; definitive emergences onto land took place during the most recent 5 million years. The sequence of character acquisition during the transition can be seen as a five-step process involving: (1) higher osteichthyan (tetrapodomorph) diversification in the Middle Devonian (beginning about 380 million years ago [mya]), (2) the emergence of "prototetrapods" (e.g., Elginerpeton) in the Frasnian stage (about 372 mya), (3) the appearance of aquatic tetrapods (e.g., Acanthostega) sometime in the early to mid-Famennian (about 360 mya), (4) the appearance of "eutetrapods" (e.g., Tulerpeton) at the very end of the Devonian period (about 358 mya), and (5) the first truly terrestrial tetrapods (e.g., Pederpes) in the Lower Carboniferous (about 340 mya). We discuss each of these steps with respect to inferred functional utility of acquired character sets. Dissociated heterochrony is seen as the most

Large-scale uniform ZnO tetrapods on catalyst free glass substrate by thermal evaporation method

Energy Technology Data Exchange (ETDEWEB)

Alsultany, Forat H., E-mail: foratusm@gmail.com [School of Physics, USM, 11800 Penang (Malaysia); Hassan, Z. [Institute of Nano-Optoelectronics Research and Technology Laboratory (INOR), USM, 11800 Penang (Malaysia); Ahmed, Naser M. [School of Physics, USM, 11800 Penang (Malaysia)

2016-07-15

Highlights: • Investigate the growth of ZnO-Ts on glass substrate by thermal evaporation method. • Glass substrate without any catalyst or a seed layer. • The morphology was controlled by adjusting the temperature of the material and the substrate. • Glass substrate was placed vertically in the quartz tube. - Abstract: Here, we report for the first time the catalyst-free growth of large-scale uniform shape and size ZnO tetrapods on a glass substrate via thermal evaporation method. Three-dimensional networks of ZnO tetrapods have needle–wire junctions, an average leg length of 2.1–2.6 μm, and a diameter of 35–240 nm. The morphology and structure of ZnO tetrapods were investigated by controlling the preparation temperature of each of the Zn powder and the glass substrate under O{sub 2} and Ar gases. Studies were carried out on ZnO tetrapods using X-ray diffraction, field emission scanning electron microscopy, UV–vis spectrophotometer, and a photoluminescence. The results showed that the sample grow in the hexagonal wurtzite structure with preferentially oriented along (002) direction, good crystallinity and high transmittance. The band gap value is about 3.27 eV. Photoluminescence spectrum exhibits a very sharp peak at 378 nm and a weak broad green emission.

Self-assembly of tetrapod-shaped CdS nanostructures into 3D networks by a transverse growth process

International Nuclear Information System (INIS)

Fu Xiuli; Li Dan; Zhang Lei; Xiao Jinghua; Li Jiangyan; Peng Zhijian; Fang Zheyu

2011-01-01

Spontaneous formation of 3D tetrapod-shaped CdS nanostructure networks has been achieved for the first time by vapor diffusion-deposition growth from CdS powders. The growth mechanism of the hexagonal and preferentially oriented CdS tetrapod-shaped nanostructures is a combination of the classic vapor-liquid-solid and vapor-solid processes, and the formation of a 3D network results from the spontaneous growths along the longitudinal and across the axial directions of the primarily formed CdS nanorods. Micro-photoluminescence measurements and near-field scanning optical microscopy investigations show that the synthesized CdS tetrapod networks have an excellent luminescence property and can be used as an optical waveguide cavities in which the guided light can be extremely confined.

Inference of the protokaryotypes of amniotes and tetrapods and the evolutionary processes of microchromosomes from comparative gene mapping.

Directory of Open Access Journals (Sweden)

Yoshinobu Uno

Full Text Available Comparative genome analysis of non-avian reptiles and amphibians provides important clues about the process of genome evolution in tetrapods. However, there is still only limited information available on the genome structures of these organisms. Consequently, the protokaryotypes of amniotes and tetrapods and the evolutionary processes of microchromosomes in tetrapods remain poorly understood. We constructed chromosome maps of functional genes for the Chinese soft-shelled turtle (Pelodiscus sinensis, the Siamese crocodile (Crocodylus siamensis, and the Western clawed frog (Xenopus tropicalis and compared them with genome and/or chromosome maps of other tetrapod species (salamander, lizard, snake, chicken, and human. This is the first report on the protokaryotypes of amniotes and tetrapods and the evolutionary processes of microchromosomes inferred from comparative genomic analysis of vertebrates, which cover all major non-avian reptilian taxa (Squamata, Crocodilia, Testudines. The eight largest macrochromosomes of the turtle and chicken were equivalent, and 11 linkage groups had also remained intact in the crocodile. Linkage groups of the chicken macrochromosomes were also highly conserved in X. tropicalis, two squamates, and the salamander, but not in human. Chicken microchromosomal linkages were conserved in the squamates, which have fewer microchromosomes than chicken, and also in Xenopus and the salamander, which both lack microchromosomes; in the latter, the chicken microchromosomal segments have been integrated into macrochromosomes. Our present findings open up the possibility that the ancestral amniotes and tetrapods had at least 10 large genetic linkage groups and many microchromosomes, which corresponded to the chicken macro- and microchromosomes, respectively. The turtle and chicken might retain the microchromosomes of the amniote protokaryotype almost intact. The decrease in number and/or disappearance of microchromosomes by repeated

Checklist of marine tetrapods (reptiles, seabirds, and mammals) of Turkey

OpenAIRE

GÜÇLÜSOY, Harun; KARAUZ, Emine Sühendan; KIRAÇ, Cem Orkun; BİLECENOĞLU, Murat

2014-01-01

The occurrence of a total of 61 marine tetrapod species is presented in this paper, including 3 sea turtles, 43 sea birds, and 15 marine mammals. Distribution of each reported species along the Black Sea, Sea of Marmara, Aegean, and Levantine coasts of Turkey is mentioned, associated with key references.

Empirical Formulae for Breakage of Dolosse and Tetrapods

OpenAIRE

Burcharth, H. F.; d'Angremond, K.; Meer, W. van der; Liu, Z.

2000-01-01

The slender, complex types of armour units, such as Tetrapods and Dolosse are widely used for rubble mound breakwaters. Many failures of such breakwaters were caused by unforeseen early breakage of the units, thus revealing an inbalance between the strength (structural integrity) of the units and the hydraulic stability (resistance to displacements) of the armour layers. Breakage occurs when the stresses from the static, pulsating and impact loads exceeds the tensile strength of the concrete....

How to quantify binaural hearing in patients with unilateral hearing using hearing implants.

Science.gov (United States)

Snik, Ad; Agterberg, Martijn; Bosman, Arjan

2015-01-01

Application of bilateral hearing devices in bilateral hearing loss and unilateral application in unilateral hearing loss (second ear with normal hearing) does not a priori lead to binaural hearing. An overview is presented on several measures of binaural benefits that have been used in patients with unilateral or bilateral deafness using one or two cochlear implants, respectively, and in patients with unilateral or bilateral conductive/mixed hearing loss using one or two percutaneous bone conduction implants (BCDs), respectively. Overall, according to this overview, the most significant and sensitive measure is the benefit in directional hearing. Measures using speech (viz. binaural summation, binaural squelch or use of the head shadow effect) showed minor benefits, except for patients with bilateral conductive/mixed hearing loss using two BCDs. Although less feasible in daily practise, the binaural masking level difference test seems to be a promising option in the assessment of binaural function. © 2015 S. Karger AG, Basel.

Formaldehyde sensor based on Ni-doped tetrapod-shaped ZnO nanopowder induced by external magnetic field

Science.gov (United States)

Bai, Zikui; Xie, Changsheng; Hu, Mulin; Zhang, Shunping

2008-12-01

The sensors based on Ni-doped ZnO nanopowder with tetrapod-shape (T-ZnO) were fabricated by screen-printing technique with external magnetic field in different direction. The morphologies and crystal structures of the thick film were characterized by X-ray diffraction (XRD) and field-emission scanning electron microscopy (FE-SEM), respectively. Gas-sensing property of sensors responded to 100 ppm formaldehyde was also detected. The results show that the direction of magnetic field has crucial effect on the sensor sensitivity. The sensors based on 5 wt% Ni-doped T-ZnO induced by magnetic field in parallel direction to the thick film surface, has the optimization sensitivity, the shortest response and recovery time, which are 10.6, 16 and 15 s, respectively. The magnetic-field induction model and the gas-sensing mechanism of the Ni-doped T-ZnO are proposed.

Effects of vertical wall and tetrapod weights on wave overtopping in rubble mound breakwaters under irregular wave conditions

Directory of Open Access Journals (Sweden)

Park Sang Kil

2014-12-01

Full Text Available Rubble mound breakwaters protect the coastal line against severe erosion caused by wave action. This study examined the performance of different sizes and properties (i.e. height of vertical wall and tetrapod size of rubble mound breakwaters on reducing the overtopping discharge. The physical model used in this study was derived based on an actual rubble mound in Busan Yacht Harbor. This research attempts to fill the gap in practical knowledge on the combined effect of the armor roughness and vertical wall on wave overtopping in rubble mound breakwaters. The main governing parameters used in this study were the vertical wall height, variation of the tetrapod weights, initial water level elevation, and the volume of overtopping under constant wave properties. The experimental results showed that the roughness factor differed according to the tetrapod size. Furthermore, the overtopping discharge with no vertical wall was similar to that with relatively short vertical walls ( 1 γv = 1. Therefore, the experimental results highlight the importance of the height of the vertical wall in reducing overtopping discharge. Moreover, a large tetrapod size may allow coastal engineers to choose a shorter vertical wall to save cost, while obtaining better performance.

Effects of vertical wall and tetrapod weights on wave overtopping in rubble mound breakwaters under irregular wave conditions

Directory of Open Access Journals (Sweden)

Sang Kil Park

2014-12-01

Full Text Available Rubble mound breakwaters protect the coastal line against severe erosion caused by wave action. This study examined the performance of different sizes and properties (i.e. height of vertical wall and tetrapod size of rubble mound breakwaters on reducing the overtopping discharge. The physical model used in this study was derived based on an actual rubble mound in Busan Yacht Harbor. This research attempts to fill the gap in practical knowledge on the combined effect of the armor roughness and vertical wall on wave overtopping in rubble mound breakwaters. The main governing parameters used in this study were the vertical wall height, variation of the tetrapod weights, initial water level elevation, and the volume of overtopping under constant wave properties. The experimental results showed that the roughness factor differed according to the tetrapod size. Furthermore, the overtopping discharge with no vertical wall was similar to that with relatively short vertical walls (γν = 1. Therefore, the experimental results highlight the importance of the height of the vertical wall in reducing overtopping discharge. Moreover, a large tetrapod size may allow coastal engineers to choose a shorter vertical wall to save cost, while obtaining better performance.

Lunge feeding in early marine reptiles and fast evolution of marine tetrapod feeding guilds.

Science.gov (United States)

Motani, Ryosuke; Chen, Xiao-hong; Jiang, Da-yong; Cheng, Long; Tintori, Andrea; Rieppel, Olivier

2015-03-10

Traditional wisdom holds that biotic recovery from the end-Permian extinction was slow and gradual, and was not complete until the Middle Triassic. Here, we report that the evolution of marine predator feeding guilds, and their trophic structure, proceeded faster. Marine reptile lineages with unique feeding adaptations emerged during the Early Triassic (about 248 million years ago), including the enigmatic Hupehsuchus that possessed an unusually slender mandible. A new specimen of this genus reveals a well-preserved palate and mandible, which suggest that it was a rare lunge feeder as also occurs in rorqual whales and pelicans. The diversity of feeding strategies among Triassic marine tetrapods reached their peak in the Early Triassic, soon after their first appearance in the fossil record. The diet of these early marine tetrapods most likely included soft-bodied animals that are not preserved as fossils. Early marine tetrapods most likely introduced a new trophic mechanism to redistribute nutrients to the top 10 m of the sea, where the primary productivity is highest. Therefore, a simple recovery to a Permian-like trophic structure does not explain the biotic changes seen after the Early Triassic.

Underwater hearing sensitivity of a male and a female Steller sea lion (Eumetopias jubatus)

NARCIS (Netherlands)

Kastelein, R.A.; Schie, R. van; Verboom, W.C.; Haan, D. de

2005-01-01

The unmasked underwater hearing sensitivities of an 8-year-old male and a 7-year-old female Steller sea lion were measured in a pool, by using behavioral psychophysics. The animals were trained with positive reinforcement to respond when they detected an acoustic signal and not to respond when they

Analysis of temperature stresses in concrete breakwater elements : Hollow cubes and Tetrapods

NARCIS (Netherlands)

Nooru-Mohamed, M.B.

1994-01-01

In this report, the results of a numerical parameter study on temperature stresses caused by hydration of cement in concrete breakwater elements are shown. Two different geometries were analysed namely hollow cubes and tetrapods. The problem encountered in solid cube breakwaters is the undesirable

Subjective Evaluation of Sound Quality for Normal-hearing and Hearing-i,paired Listeners

DEFF Research Database (Denmark)

Nielsen, Lars Bramsløw

1992-01-01

11 hearing-impaired (HI) and 12 normal-hearing (NH) subjects have performed sound quality ratings on 6 perceptual scales (Loudness, Clarity, Sharpness, Fullness, Spaciousness and Overall judgement). The signals for the rating experiment consisted of running speech and music with or without......, but the normal-hearing group was slightly more reliable. There were significant differences between stimuli and between subjects, with stimuli affecting the ratings the most. Normal-hearing and hearing-impaired subjects showed similar trends, but normal-hearing listeners were generally more sensitive, i...

Comparative analysis of the skeletal changes in tetrapods after brief influence of microgravity.

Science.gov (United States)

Nikitin, V B; Gulimova, V I; Ilyin, E A; Asadchikov, V E; Buzmakov, A V; Okshtein, I L; Saveliev, S V

2007-07-01

Experiments involving lower tetrapods demonstrate that the degree of skeletal demineralization in spaceflights is related to the type of environmental behaviour of the animal. Probably the sensing of support reaction decreases the negative effect of spaceflight upon the bone tissue.

Study of tetrapodal ZnO-PDMS composites: a comparison of fillers shapes in stiffness and hydrophobicity improvements.

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Xin Jin

Full Text Available ZnO particles of different size and structures were used as fillers to modify the silicone rubber, in order to reveal the effect of the filler shape in the polymer composites. Tetrapodal shaped microparticles, short microfibers/whiskers, and nanosized spherical particles from ZnO have been used as fillers to fabricate the different ZnO-Silicone composites. The detailed microstructures of the fillers as well as synthesized composites using scanning electron microscopy have been presented here. The tensile elastic modulus and water contact angle, which are important parameters for bio-mimetic applications, of fabricated composites with different fillers have been measured and compared. Among all three types of fillers, tetrapodal shaped ZnO microparticles showed the best performance in terms of increase in hydrophobicity of material cross-section as well as the stiffness of the composites. It has been demonstrated that the tetrapodal shaped microparticles gain their advantage due to the special shape, which avoids agglomeration problems as in the case for nanoparticles, and the difficulty of achieving truly random distribution for whisker fillers.

Study of tetrapodal ZnO-PDMS composites: a comparison of fillers shapes in stiffness and hydrophobicity improvements.

Science.gov (United States)

Jin, Xin; Deng, Mao; Kaps, Sören; Zhu, Xinwei; Hölken, Iris; Mess, Kristin; Adelung, Rainer; Mishra, Yogendra Kumar

2014-01-01

ZnO particles of different size and structures were used as fillers to modify the silicone rubber, in order to reveal the effect of the filler shape in the polymer composites. Tetrapodal shaped microparticles, short microfibers/whiskers, and nanosized spherical particles from ZnO have been used as fillers to fabricate the different ZnO-Silicone composites. The detailed microstructures of the fillers as well as synthesized composites using scanning electron microscopy have been presented here. The tensile elastic modulus and water contact angle, which are important parameters for bio-mimetic applications, of fabricated composites with different fillers have been measured and compared. Among all three types of fillers, tetrapodal shaped ZnO microparticles showed the best performance in terms of increase in hydrophobicity of material cross-section as well as the stiffness of the composites. It has been demonstrated that the tetrapodal shaped microparticles gain their advantage due to the special shape, which avoids agglomeration problems as in the case for nanoparticles, and the difficulty of achieving truly random distribution for whisker fillers.

Terrestrial-style feeding in a very early aquatic tetrapod is supported by evidence from experimental analysis of suture morphology.

Science.gov (United States)

Markey, Molly J; Marshall, Charles R

2007-04-24

There is no consensus on when in the fish-tetrapod transition suction feeding, the primary method of prey capture in the aquatic realm, evolved into the direct biting on prey typical of terrestrial animals. Here, we show that differences in the morphology of selected cranial sutures between species that span the fish-tetrapod transition (the Devonian osteolepiform fish Eusthenopteron, the aquatic Devonian tetrapod Acanthostega, and the Permian terrestrial tetrapod Phonerpeton) can be used to infer when terrestrial feeding first appeared. Our approach consists of defining a sutural morphospace, assigning functional fields to that morphospace based on our previous measurements of suture function made during feeding in the living fish Polypterus, inferring the functions of the fossil sutures based on where they fall in the morphospace, and then using the correlation between feeding mode and the patterns of inferred suture function across the skull roof in taxa where feeding mode is unambiguous to infer the feeding mode practiced by Acanthostega. Using this procedure, we find that the suture morphologies of Acanthostega are inconsistent with the hypothesis that it captured prey primarily by means of suction, which suggests that it may have bitten directly on prey at or near the water's edge. Thus, our data strongly support the hypothesis that the terrestrial mode of feeding first emerged in aquatic taxa.

Noise and Hearing Protection

Science.gov (United States)

... ENTCareers Marketplace Find an ENT Doctor Near You Noise and Hearing Protection Noise and Hearing Protection Patient ... it is. How can I tell if a noise is dangerous? People differ in their sensitivity to ...

Sensitivity and specificity of scales ELI, SAL, MODIFIED LARSEN, KLOCKHOFF and NIOSH rating for professional hearing loss, Popayán Colombia

Directory of Open Access Journals (Sweden)

Aura Teresa Palacios-Pérez

2010-09-01

Full Text Available Objective: To determine the sensitivity and specificity of five available scales to the qualification of the Tonal Audiometry for the detection of occupationally induced hearing loss. Methods: A descriptive cross-sectional study was conducted. The study population was 92 adult workers. Participants underwent the application of the different formats of registration of the results and qualification of the tonal audiometry. Participants received a hearing evaluation by clinical audiometry. Sixty four cases met the inclusion criteria and were selected for the final analysis.Once the tonal audiometry was complete, evaluation of occupationally induced hearing loss was done by using the ELI, salt, modified LARSEN, KLOCKHOFF and NIOSH classification scales. Results were compared to FREQUENCIAL analysis. Results: The LARSEN scale was noted to detect more cases of occupationally induced hearing loss. The LARSEN modified, represented detection in 54.69% of cases for right ear and 56.25% of cases for left ear. On the other hand, noted the direct relationship of hearing loss with regard to the age. No direct correlation to time of noise exposure was found.. Conclusions: The rating scale that presented greater sensitivity was the LARSEN modified. It was represented by 93.1% and a specificity of 100%.

The signature of human pressure history on the biogeography of body mass in tetrapods

NARCIS (Netherlands)

Rapacciuolo, Giovanni; Marin, Julie; Costa, Gabriel C.; Helmus, Matthew R.; Behm, Jocelyn E.; Brooks, Thomas M.; Hedges, S. Blair; Radeloff, Volker C.; Young, Bruce E.; Graham, Catherine H.

2017-01-01

Aim: Examining the biogeography of body size is crucial for understanding how animal communities are assembled and maintained. In tetrapods, body size varies predictably with temperature, moisture, productivity seasonality and topographical complexity. Although millennial-scale human pressures are

Feeding biomechanics in Acanthostega and across the fish–tetrapod transition

OpenAIRE

Neenan, James M.; Ruta, Marcello; Clack, Jennifer A.; Rayfield, Emily J.

2014-01-01

Acanthostega is one of the earliest and most primitive limbed vertebrates. Its numerous fish-like features indicate a primarily aquatic lifestyle, yet cranial suture morphology suggests that its skull is more similar to those of terrestrial taxa. Here, we apply geometric morphometrics and two-dimensional finite-element analysis to the lower jaws of Acanthostega and 22 other tetrapodomorph taxa in order to quantify morphological and functional changes across the fish–tetrapod transition. The j...

Individual Hearing Loss

Directory of Open Access Journals (Sweden)

Sébastien Santurette

2016-06-01

Full Text Available It is well-established that hearing loss does not only lead to a reduction of hearing sensitivity. Large individual differences are typically observed among listeners with hearing impairment in a wide range of suprathreshold auditory measures. In many cases, audiometric thresholds cannot fully account for such individual differences, which make it challenging to find adequate compensation strategies in hearing devices. How to characterize, model, and compensate for individual hearing loss were the main topics of the fifth International Symposium on Auditory and Audiological Research (ISAAR, held in Nyborg, Denmark, in August 2015. The following collection of papers results from some of the work that was presented and discussed at the symposium.

Comparative assessment of amphibious hearing in pinnipeds.

Science.gov (United States)

Reichmuth, Colleen; Holt, Marla M; Mulsow, Jason; Sills, Jillian M; Southall, Brandon L

2013-06-01

Auditory sensitivity in pinnipeds is influenced by the need to balance efficient sound detection in two vastly different physical environments. Previous comparisons between aerial and underwater hearing capabilities have considered media-dependent differences relative to auditory anatomy, acoustic communication, ecology, and amphibious life history. New data for several species, including recently published audiograms and previously unreported measurements obtained in quiet conditions, necessitate a re-evaluation of amphibious hearing in pinnipeds. Several findings related to underwater hearing are consistent with earlier assessments, including an expanded frequency range of best hearing in true seals that spans at least six octaves. The most notable new results indicate markedly better aerial sensitivity in two seals (Phoca vitulina and Mirounga angustirostris) and one sea lion (Zalophus californianus), likely attributable to improved ambient noise control in test enclosures. An updated comparative analysis alters conventional views and demonstrates that these amphibious pinnipeds have not necessarily sacrificed aerial hearing capabilities in favor of enhanced underwater sound reception. Despite possessing underwater hearing that is nearly as sensitive as fully aquatic cetaceans and sirenians, many seals and sea lions have retained acute aerial hearing capabilities rivaling those of terrestrial carnivores.

A unique life history among tetrapods: an annual chameleon living mostly as an egg.

Science.gov (United States)

Karsten, Kristopher B; Andriamandimbiarisoa, Laza N; Fox, Stanley F; Raxworthy, Christopher J

2008-07-01

The approximately 28,300 species of tetrapods (four-limbed vertebrates) almost exclusively have perennial life spans. Here, we report the discovery of a remarkable annual tetrapod from the arid southwest of Madagascar: the chameleon Furcifer labordi, with a posthatching life span of just 4-5 months. At the start of the active season (November), an age cohort of hatchlings emerges; larger juveniles or adults are not present. These hatchlings grow rapidly, reach sexual maturity in less than 2 months, and reproduce in January-February. After reproduction, senescence appears, and the active season concludes with population-wide adult death. Consequently, during the dry season, the entire population is represented by developing eggs that incubate for 8-9 months before synchronously hatching at the onset of the following rainy season. Remarkably, this chameleon spends more of its short annual life cycle inside the egg than outside of it. Our review of tetrapod longevity (>1,700 species) finds no others with such a short life span. These findings suggest that the notorious rapid death of chameleons in captivity may, for some species, actually represent the natural adult life span. Consequently, a new appraisal may be warranted concerning the viability of chameleon breeding programs, which could have special significance for species of conservation concern. Additionally, because F. labordi is closely related to other perennial species, this chameleon group may prove also to be especially well suited for comparative studies that focus on life history evolution and the ecological, genetic, and/or hormonal determinants of aging, longevity, and senescence.

Diminished behavioral and neural sensitivity to sound modulation is associated with moderate developmental hearing loss.

Directory of Open Access Journals (Sweden)

Merri J Rosen

Full Text Available The acoustic rearing environment can alter central auditory coding properties, yet altered neural coding is seldom linked with specific deficits to adult perceptual skills. To test whether developmental hearing loss resulted in comparable changes to perception and sensory coding, we examined behavioral and neural detection thresholds for sinusoidally amplitude modulated (sAM stimuli. Behavioral sAM detection thresholds for slow (5 Hz modulations were significantly worse for animals reared with bilateral conductive hearing loss (CHL, as compared to controls. This difference could not be attributed to hearing thresholds, proficiency at the task, or proxies for attention. Detection thresholds across the groups did not differ for fast (100 Hz modulations, a result paralleling that seen in humans. Neural responses to sAM stimuli were recorded in single auditory cortex neurons from separate groups of awake animals. Neurometric analyses indicated equivalent thresholds for the most sensitive neurons, but a significantly poorer detection threshold for slow modulations across the population of CHL neurons as compared to controls. The magnitude of the neural deficit matched that of the behavioral differences, suggesting that a reduction of sensory information can account for limitations to perceptual skills.

Does hearing aid use affect audiovisual integration in mild hearing impairment?

Science.gov (United States)

Gieseler, Anja; Tahden, Maike A S; Thiel, Christiane M; Colonius, Hans

2018-04-01

There is converging evidence for altered audiovisual integration abilities in hearing-impaired individuals and those with profound hearing loss who are provided with cochlear implants, compared to normal-hearing adults. Still, little is known on the effects of hearing aid use on audiovisual integration in mild hearing loss, although this constitutes one of the most prevalent conditions in the elderly and, yet, often remains untreated in its early stages. This study investigated differences in the strength of audiovisual integration between elderly hearing aid users and those with the same degree of mild hearing loss who were not using hearing aids, the non-users, by measuring their susceptibility to the sound-induced flash illusion. We also explored the corresponding window of integration by varying the stimulus onset asynchronies. To examine general group differences that are not attributable to specific hearing aid settings but rather reflect overall changes associated with habitual hearing aid use, the group of hearing aid users was tested unaided while individually controlling for audibility. We found greater audiovisual integration together with a wider window of integration in hearing aid users compared to their age-matched untreated peers. Signal detection analyses indicate that a change in perceptual sensitivity as well as in bias may underlie the observed effects. Our results and comparisons with other studies in normal-hearing older adults suggest that both mild hearing impairment and hearing aid use seem to affect audiovisual integration, possibly in the sense that hearing aid use may reverse the effects of hearing loss on audiovisual integration. We suggest that these findings may be particularly important for auditory rehabilitation and call for a longitudinal study.

Moth hearing and sound communication

DEFF Research Database (Denmark)

Nakano, Ryo; Takanashi, Takuma; Surlykke, Annemarie

2015-01-01

Active echolocation enables bats to orient and hunt the night sky for insects. As a counter-measure against the severe predation pressure many nocturnal insects have evolved ears sensitive to ultrasonic bat calls. In moths bat-detection was the principal purpose of hearing, as evidenced by compar......Active echolocation enables bats to orient and hunt the night sky for insects. As a counter-measure against the severe predation pressure many nocturnal insects have evolved ears sensitive to ultrasonic bat calls. In moths bat-detection was the principal purpose of hearing, as evidenced...... by comparable hearing physiology with best sensitivity in the bat echolocation range, 20–60 kHz, across moths in spite of diverse ear morphology. Some eared moths subsequently developed sound-producing organs to warn/startle/jam attacking bats and/or to communicate intraspecifically with sound. Not only...... the sounds for interaction with bats, but also mating signals are within the frequency range where bats echolocate, indicating that sound communication developed after hearing by “sensory exploitation”. Recent findings on moth sound communication reveal that close-range (~ a few cm) communication with low...

Impedance-matching hearing in Paleozoic reptiles: evidence of advanced sensory perception at an early stage of amniote evolution.

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Johannes Müller

Full Text Available BACKGROUND: Insights into the onset of evolutionary novelties are key to the understanding of amniote origins and diversification. The possession of an impedance-matching tympanic middle ear is characteristic of all terrestrial vertebrates with a sophisticated hearing sense and an adaptively important feature of many modern terrestrial vertebrates. Whereas tympanic ears seem to have evolved multiple times within tetrapods, especially among crown-group members such as frogs, mammals, squamates, turtles, crocodiles, and birds, the presence of true tympanic ears has never been recorded in a Paleozoic amniote, suggesting they evolved fairly recently in amniote history. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, we performed a morphological examination and a phylogenetic analysis of poorly known parareptiles from the Middle Permian of the Mezen River Basin in Russia. We recovered a well-supported clade that is characterized by a unique cheek morphology indicative of a tympanum stretching across large parts of the temporal region to an extent not seen in other amniotes, fossil or extant, and a braincase specialized in showing modifications clearly related to an increase in auditory function, unlike the braincase of any other Paleozoic tetrapod. In addition, we estimated the ratio of the tympanum area relative to the stapedial footplate for the basalmost taxon of the clade, which, at 23:1, is in close correspondence to that of modern amniotes capable of efficient impedance-matching hearing. CONCLUSIONS/SIGNIFICANCE: Using modern amniotes as analogues, the possession of an impedance-matching middle ear in these parareptiles suggests unique ecological adaptations potentially related to living in dim-light environments. More importantly, our results demonstrate that already at an early stage of amniote diversification, and prior to the Permo-Triassic extinction event, the complexity of terrestrial vertebrate ecosystems had reached a level that

Obtaining Data on Hearing Experience Through Self-tracking

DEFF Research Database (Denmark)

Johansen, Benjamin; Petersen, Michael Kai; Larsen, Jakob Eg

2016-01-01

This position paper argues that self-tracking data can enrich a pre-fitting process of hearing aids. It is argued that hearing loss consist of three parts. Tonal sensitivity, signal to-noise-sensitivity, and cognitive capabilities which can be assessed by using smartphones. Combining this with co...

Confusing dinosaurs with mammals: tetrapod phylogenetics and anatomical terminology in the world of homology.

Science.gov (United States)

Harris, Jerald D

2004-12-01

At present, three different systems of anatomical nomenclature are available to researchers describing new tetrapod taxa: a nonstandardized traditional system erected in part by Sir Richard Owen and subsequently elaborated by Alfred Romer; a standardized system created for avians, the Nomina Anatomica Avium (NAA); and a standardized system for extant (crown-group) mammals, the Nomina Anatomica Veterinaria (NAV). Conserved homologous structures widely distributed within the Tetrapoda are often granted different names in each system. The recent shift toward a phylogenetic system based on homology requires a concomitant shift toward a single nomenclatural system also based on both evolutionary and functional morphological homology. Standardized terms employed in the NAA and NAV should be perpetuated as far as possible basally in their respective phylogenies. Thus, NAA terms apply to nonavian archosaurs (or even all diapsids) and NAV terms apply to noncrown-group mammals and more basal synapsids. Taxa equally distant from both avians and crown-group mammals may maintain the traditional nonstandardized terminology until a universal anatomical nomenclature for all tetrapods is constructed. (c) 2004 Wiley-Liss, Inc.

Skull ontogeny: developmental patterns of fishes conserved across major tetrapod clades.

Science.gov (United States)

Schoch, Rainer R

2006-01-01

In vertebrates, the ontogeny of the bony skull forms a particularly complex part of embryonic development. Although this area used to be restricted to neontology, recent discoveries of fossil ontogenies provide an additional source of data. One of the most detailed ossification sequences is known from Permo-Carboniferous amphibians, the branchiosaurids. These temnospondyls form a near-perfect link between the piscine osteichthyans and the various clades of extant tetrapods, retaining a full complement of dermal bones in the skull. For the first time, the broader evolutionary significance of these event sequences is analyzed, focusing on the identification of sequence heterochronies. A set of 120 event pairs was analyzed by event pair cracking, which helped identify active movers. A cladistic analysis of the event pair data was also carried out, highlighting some shared patterns between widely divergent clades of tetrapods. The analyses revealed an unexpected degree of similarity between the widely divergent taxa. Most interesting is the apparently modular composition of the cranial sequence: five clusters of bones were discovered in each of which the elements form in the same time window: (1) jaw bones, (2) marginal palatal elements, (3) circumorbital bones, (4) skull roof elements, and (5) neurocranial ossifications. In the studied taxa, these "modules" have in most cases been shifted fore and back on the trajectory relative to the Amia sequence, but did not disintegrate. Such "modules" might indicate a high degree of evolutionary limitation (constraint).

Periodontal ligament, cementum, and alveolar bone in the oldest herbivorous tetrapods, and their evolutionary significance.

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Aaron R H LeBlanc

Full Text Available Tooth implantation provides important phylogenetic and functional information about the dentitions of amniotes. Traditionally, only mammals and crocodilians have been considered truly thecodont, because their tooth roots are coated in layers of cementum for anchorage of the periodontal ligament, which is in turn attached to the bone lining the alveolus, the alveolar bone. The histological properties and developmental origins of these three periodontal tissues have been studied extensively in mammals and crocodilians, but the identities of the periodontal tissues in other amniotes remain poorly studied. Early work on dental histology of basal amniotes concluded that most possess a simplified tooth attachment in which the tooth root is ankylosed to a pedestal composed of "bone of attachment", which is in turn fused to the jaw. More recent studies have concluded that stereotypically thecodont tissues are also present in non-mammalian, non-crocodilian amniotes, but these studies were limited to crown groups or secondarily aquatic reptiles. As the sister group to Amniota, and the first tetrapods to exhibit dental occlusion, diadectids are the ideal candidates for studies of dental evolution among terrestrial vertebrates because they can be used to test hypotheses of development and homology in deep time. Our study of Permo-Carboniferous diadectid tetrapod teeth and dental tissues reveal the presence of two types of cementum, periodontal ligament, and alveolar bone, and therefore the earliest record of true thecodonty in a tetrapod. These discoveries in a stem amniote allow us to hypothesize that the ability to produce the tissues that characterize thecodonty in mammals and crocodilians is very ancient and plesiomorphic for Amniota. Consequently, all other forms of tooth implantation in crown amniotes are derived arrangements of one or more of these periodontal tissues and not simply ankylosis of teeth to the jaw by plesiomorphically retaining "bone

Contrast sensitivity abnormalities in deaf individuals

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Masoud Khorrami-Nejad

2018-01-01

Conclusion: Hearing impaired boys are at a greater risk for contrast sensitivity abnormalities than boys with normal hearing. The larger frequency of contrast sensitivity abnormalities in high spatial frequencies than in other frequencies may demonstrate greater defects in the central visual system compared with the periphery in individuals with hearing loss.

Carnivorous dinocephalian from the Middle Permian of Brazil and tetrapod dispersal in Pangaea.

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Cisneros, Juan Carlos; Abdala, Fernando; Atayman-Güven, Saniye; Rubidge, Bruce S; Şengörc, A M Celâl; Schultz, Cesar L

2012-01-31

The medial Permian (~270-260 Ma: Guadalupian) was a time of important tetrapod faunal changes, in particular reflecting a turnover from pelycosaurian- to therapsid-grade synapsids. Until now, most knowledge on tetrapod distribution during the medial Permian has come from fossils found in the South African Karoo and the Russian Platform, whereas other areas of Pangaea are still poorly known. We present evidence for the presence of a terrestrial carnivorous vertebrate from the Middle Permian of South America based on a complete skull. Pampaphoneus biccai gen. et sp. nov. was a dinocephalian "mammal-like reptile" member of the Anteosauridae, an early therapsid predator clade known only from the Middle Permian of Russia, Kazakhstan, China, and South Africa. The genus is characterized, among other features, by postorbital bosses, short, bulbous postcanines, and strongly recurved canines. Phylogenetic analysis indicates that the Brazilian dinocephalian occupies a middle position within the Anteosauridae, reinforcing the model of a global distribution for therapsids as early as the Guadalupian. The close phylogenetic relationship of the Brazilian species to dinocephalians from South Africa and the Russian Platform suggests a closer faunistic relationship between South America and eastern Europe than previously thought, lending support to a Pangaea B-type continental reconstruction.

[Evolution of speech and hearing].

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Pitkäranta, Anne

2009-01-01

Actual spoken language of man developed only approximately 200,000 to 100,000 years ago. As a result of natural selection, man has developed hearing, which is most sensitive in the frequency regions of 200 to 4000 Hz, corresponding to those of spoken sounds. Functional hearing has been one of the prerequisites for the development of speech, although according to current opinion the language itself may have evolved by mimicking gestures with the so-called mirror neurons. Due to hearing, gesticulation was no longer necessary, and the hands became available for other purposes.

Predicting hearing thresholds in occupational noise-induced hearing loss by auditory steady state responses.

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Attias, Joseph; Karawani, Hanin; Shemesh, Rafi; Nageris, Ben

2014-01-01

Currently available behavioral tools for the assessment of noise-induced hearing loss (NIHL) depend on the reliable cooperation of the subject. Furthermore, in workers' compensation cases, there is considerable financial gain to be had from exaggerating symptoms, such that accurate assessment of true hearing threshold levels is essential. An alternative objective physiologic tool for assessing NIHL is the auditory steady state response (ASSR) test, which combines frequency specificity with a high level of auditory stimulation, making it applicable for the evaluation of subjects with a moderate to severe deficit. The primary aim of the study was to assess the value of the multifrequency ASSR test in predicting the behavioral warble-tone audiogram in a large sample of young subjects with NIHL of varying severity or with normal hearing. The secondary goal was to assess suprathreshold ASSR growth functions in these two groups. The study group included 157 subjects regularly exposed to high levels of occupational noise, who attended a university-associated audiological clinic for evaluation of NIHL from 2009 through 2011. All underwent a behavioral audiogram, and on the basis of the findings, were divided into those with NIHL (108 subjects, 216 ears) or normal hearing (49 subjects, 98 ears). The accuracy of the ASSR threshold estimations for frequencies of 500, 1000, 2000, and 4000 Hz was compared between groups, and the specificity and sensitivity of the ASSR test in differentiating ears with or without NIHL was calculated using receiver operating characteristic analysis. Linear regression analysis was used to formulate an equation to predict the behavioral warble-tone audiogram at each test frequency using ASSR thresholds. Multifrequency ASSR amplitude growth as a function of stimulus intensity was compared between the NIHL and normal-hearing groups for 1000 Hz and 4000 Hz carrier frequencies. In the subjects with NIHL, ASSR thresholds to various frequencies were

Perception of a Sung Vowel as a Function of Frequency-Modulation Rate and Excursion in Listeners with Normal Hearing and Hearing Impairment

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Vatti, Marianna; Santurette, Sébastien; Pontoppidan, Niels Henrik; Dau, Torsten

2014-01-01

Purpose: Frequency fluctuations in human voices can usually be described as coherent frequency modulation (FM). As listeners with hearing impairment (HI listeners) are typically less sensitive to FM than listeners with normal hearing (NH listeners), this study investigated whether hearing loss affects the perception of a sung vowel based on FM…

Faunal turnover of marine tetrapods during the Jurassic-Cretaceous transition.

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Benson, Roger B J; Druckenmiller, Patrick S

2014-02-01

Marine and terrestrial animals show a mosaic of lineage extinctions and diversifications during the Jurassic-Cretaceous transition. However, despite its potential importance in shaping animal evolution, few palaeontological studies have focussed on this interval and the possible climate and biotic drivers of its faunal turnover. In consequence evolutionary patterns in most groups are poorly understood. We use a new, large morphological dataset to examine patterns of lineage diversity and disparity (variety of form) in the marine tetrapod clade Plesiosauria, and compare these patterns with those of other organisms. Although seven plesiosaurian lineages have been hypothesised as crossing the Jurassic-Cretaceous boundary, our most parsimonious topology suggests the number was only three. The robust recovery of a novel group including most Cretaceous plesiosauroids (Xenopsaria, new clade) is instrumental in this result. Substantial plesiosaurian turnover occurred during the Jurassic-Cretaceous boundary interval, including the loss of substantial pliosaurid, and cryptoclidid diversity and disparity, followed by the radiation of Xenopsaria during the Early Cretaceous. Possible physical drivers of this turnover include climatic fluctuations that influenced oceanic productivity and diversity: Late Jurassic climates were characterised by widespread global monsoonal conditions and increased nutrient flux into the opening Atlantic-Tethys, resulting in eutrophication and a highly productive, but taxonomically depauperate, plankton. Latest Jurassic and Early Cretaceous climates were more arid, resulting in oligotrophic ocean conditions and high taxonomic diversity of radiolarians, calcareous nannoplankton and possibly ammonoids. However, the observation of discordant extinction patterns in other marine tetrapod groups such as ichthyosaurs and marine crocodylomorphs suggests that clade-specific factors may have been more important than overarching extrinsic drivers of faunal

Phylogenomic analysis of vertebrate thrombospondins reveals fish-specific paralogues, ancestral gene relationships and a tetrapod innovation

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Adams Josephine C

2006-04-01

Full Text Available Abstract Background Thrombospondins (TSPs are evolutionarily-conserved, extracellular, calcium-binding glycoproteins with important roles in cell-extracellular matrix interactions, angiogenesis, synaptogenesis and connective tissue organisation. Five TSPs, designated TSP-1 through TSP-5, are encoded in the human genome. All but one have known roles in acquired or inherited human diseases. To further understand the roles of TSPs in human physiology and pathology, it would be advantageous to extend the repertoire of relevant vertebrate models. In general the zebrafish is proving an excellent model organism for vertebrate biology, therefore we set out to evaluate the status of TSPs in zebrafish and two species of pufferfish. Results We identified by bioinformatics that three fish species encode larger numbers of TSPs than vertebrates, yet all these sequences group as homologues of TSP-1 to -4. By phylogenomic analysis of neighboring genes, we uncovered that, in fish, a TSP-4-like sequence is encoded from the gene corresponding to the tetrapod TSP-5 gene. Thus, all TSP genes show conservation of synteny between fish and tetrapods. In the human genome, the TSP-1, TSP-3, TSP-4 and TSP-5 genes lie within paralogous regions that provide insight into the ancestral genomic context of vertebrate TSPs. Conclusion A new model for TSP evolution in vertebrates is presented. The TSP-5 protein sequence has evolved rapidly from a TSP-4-like sequence as an innovation in the tetrapod lineage. TSP biology in fish is complicated by the presence of additional lineage- and species-specific TSP paralogues. These novel results give deeper insight into the evolution of TSPs in vertebrates and open new directions for understanding the physiological and pathological roles of TSP-4 and TSP-5 in humans.

Sensitivity of cortical auditory evoked potential detection for hearing-impaired infants in response to short speech sounds

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Bram Van Dun

2012-01-01

Full Text Available

Background: Cortical auditory evoked potentials (CAEPs are an emerging tool for hearing aid fitting evaluation in young children who cannot provide reliable behavioral feedback. It is therefore useful to determine the relationship between the sensation level of speech sounds and the detection sensitivity of CAEPs.

Design and methods: Twenty-five sensorineurally hearing impaired infants with an age range of 8 to 30 months were tested once, 18 aided and 7 unaided. First, behavioral thresholds of speech stimuli /m/, /g/, and /t/ were determined using visual reinforcement orientation audiometry (VROA. Afterwards, the same speech stimuli were presented at 55, 65, and 75 dB SPL, and CAEP recordings were made. An automatic statistical detection paradigm was used for CAEP detection.

Results: For sensation levels above 0, 10, and 20 dB respectively, detection sensitivities were equal to 72 ± 10, 75 ± 10, and 78 ± 12%. In 79% of the cases, automatic detection p-values became smaller when the sensation level was increased by 10 dB.

Conclusions: The results of this study suggest that the presence or absence of CAEPs can provide some indication of the audibility of a speech sound for infants with sensorineural hearing loss. The detection of a CAEP provides confidence, to a degree commensurate with the detection probability, that the infant is detecting that sound at the level presented. When testing infants where the audibility of speech sounds has not been established behaviorally, the lack of a cortical response indicates the possibility, but by no means a certainty, that the sensation level is 10 dB or less.

Right-Ear Advantage for Speech-in-Noise Recognition in Patients with Nonlateralized Tinnitus and Normal Hearing Sensitivity.

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Tai, Yihsin; Husain, Fatima T

2018-04-01

Despite having normal hearing sensitivity, patients with chronic tinnitus may experience more difficulty recognizing speech in adverse listening conditions as compared to controls. However, the association between the characteristics of tinnitus (severity and loudness) and speech recognition remains unclear. In this study, the Quick Speech-in-Noise test (QuickSIN) was conducted monaurally on 14 patients with bilateral tinnitus and 14 age- and hearing-matched adults to determine the relation between tinnitus characteristics and speech understanding. Further, Tinnitus Handicap Inventory (THI), tinnitus loudness magnitude estimation, and loudness matching were obtained to better characterize the perceptual and psychological aspects of tinnitus. The patients reported low THI scores, with most participants in the slight handicap category. Significant between-group differences in speech-in-noise performance were only found at the 5-dB signal-to-noise ratio (SNR) condition. The tinnitus group performed significantly worse in the left ear than in the right ear, even though bilateral tinnitus percept and symmetrical thresholds were reported in all patients. This between-ear difference is likely influenced by a right-ear advantage for speech sounds, as factors related to testing order and fatigue were ruled out. Additionally, significant correlations found between SNR loss in the left ear and tinnitus loudness matching suggest that perceptual factors related to tinnitus had an effect on speech-in-noise performance, pointing to a possible interaction between peripheral and cognitive factors in chronic tinnitus. Further studies, that take into account both hearing and cognitive abilities of patients, are needed to better parse out the effect of tinnitus in the absence of hearing impairment.

Hybrid nanocrystal/polymer solar cells based on tetrapod-shaped CdSexTe1-x nanocrystals

International Nuclear Information System (INIS)

Zhou Yi; Li Yunchao; Zhong Haizheng; Hou Jianhui; Ding Yuqin; Yang Chunhe; Li Yongfang

2006-01-01

A series of ternary tetrapodal nanocrystals of CdSe x Te 1-x with x = 0 (CdTe), 0.23, 0.53, 0.78, 1 (CdSe) were synthesized and used to fabricate hybrid nanocrystal/polymer solar cells. Herein, the nanocrystals acted as electron acceptors, and poly(2-methoxy-5-(2'-ethyl-hexyloxy)-1,4-phenylene vinylene) (MEH-PPV) was used as an electron donor. It was found that the open circuit voltage (V oc ), short-circuit current (J sc ) and power conversion efficiency (η) of the devices all increased with increasing Se content in the CdSe x Te 1-x nanocrystals under identical experimental conditions. The solar cell based on the blend of tetrapodal CdSe nanocrystals and MEH-PPV (9:1 w/w) showed the highest power conversion efficiency of 1.13% under AM 1.5, 80 mW cm -2 , and the maximum incident photon to converted current efficiency (IPCE) of the device reached 47% at 510 nm. The influence of nanocrystal composition on the photovoltaic properties of the hybrid solar cells was explained by the difference of the band level positions between MEH-PPV and the nanocrystals

Empirical Formulae for Breakage of Dolosse and Tetrapods

DEFF Research Database (Denmark)

Burcharth, H. F.; d'Angremond, K.; Meer, W. van der

2000-01-01

The slender, complex types of armour units, such as Tetrapods and Dolosse are widely used for rubble mound breakwaters. Many failures of such breakwaters were caused by unforeseen early breakage of the units, thus revealing an inbalance between the strength (structural integrity) of the units...... and the hydraulic stability (resistance to displacements) of the armour layers. Breakage occurs when the stresses from the static, pulsating and impact loads exceeds the tensile strength of the concrete. While the hydraulic stability can be studied in Froude-scale hydraulic model tests, it is not possible to study...... armour unit stresses in small scale models. This is partly because the strain in model armour units are too small to be recorded, and partly because the scaling law for impact load generated stresses is nonlinear. The paper discusses the scaling laws related to type of stresses and presents a method...

Factors Affecting Sentence-in-Noise Recognition for Normal Hearing Listeners and Listeners with Hearing Loss.

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Hwang, Jung Sun; Kim, Kyung Hyun; Lee, Jae Hee

2017-07-01

Despite amplified speech, listeners with hearing loss often report more difficulties understanding speech in background noise compared to normalhearing listeners. Various factors such as deteriorated hearing sensitivity, age, suprathreshold temporal resolution, and reduced capacity of working memory and attention can attribute to their sentence-in-noise problems. The present study aims to determine a primary explanatory factor for sentence-in-noise recognition difficulties in adults with or without hearing loss. Forty normal-hearing (NH) listeners (23-73 years) and thirty-four hearing-impaired (HI) listeners (24-80 years) participated for experimental testing. For both NH and HI group, the younger, middle-aged, older listeners were included. The sentence recognition score in noise was measured at 0 dB signal-to-noise ratio. The ability of temporal resolution was evaluated by gap detection performance using the Gaps-In-Noise test. Listeners' short-term auditory working memory span was measured by forward and backward digit spans. Overall, the HI listeners' sentence-in-noise recognition, temporal resolution abilities, and digit forward and backward spans were poorer compared to the NH listeners. Both NH and HI listeners had a substantial variability in performance. For NH listeners, only the digit backward span explained a small proportion of the variance in their sentence-in-noise performance. For the HI listeners, all the performance was influenced by age, and their sentence-in-noise difficulties were associated with various factors such as high-frequency hearing sensitivity, suprathreshold temporal resolution abilities, and working memory span. For the HI listeners, the critical predictors of the sentence-in-noise performance were composite measures of peripheral hearing sensitivity and suprathreshold temporal resolution abilities. The primary explanatory factors for the sentence-in-noise recognition performance differ between NH and HI listeners. Factors

Identifying hearing loss by means of iridology.

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Stearn, Natalie; Swanepoel, De Wet

2006-11-13

Isolated reports of hearing loss presenting as markings on the iris exist, but to date the effectiveness of iridology to identify hearing loss has not been investigated. This study therefore aimed to determine the efficacy of iridological analysis in the identification of moderate to profound sensorineural hearing loss in adolescents. A controlled trial was conducted with an iridologist, blind to the actual hearing status of participants, analyzing the irises of participants with and without hearing loss. Fifty hearing impaired and fifty normal hearing subjects, between the ages of 15 and 19 years, controlled for gender, participated in the study. An experienced iridologist analyzed the randomised set of participants' irises. A 70% correct identification of hearing status was obtained by iridological analyses with a false negative rate of 41% compared to a 19% false positive rate. The respective sensitivity and specificity rates therefore came to 59% and 81%. Iridological analysis of hearing status indicated a statistically significant relationship to actual hearing status (P iridology were not comparable to those of traditional audiological screening procedures.

Smartphone-Based Hearing Screening in Noisy Environments

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Youngmin Na

2014-06-01

Full Text Available It is important and recommended to detect hearing loss as soon as possible. If it is found early, proper treatment may help improve hearing and reduce the negative consequences of hearing loss. In this study, we developed smartphone-based hearing screening methods that can ubiquitously test hearing. However, environmental noise generally results in the loss of ear sensitivity, which causes a hearing threshold shift (HTS. To overcome this limitation in the hearing screening location, we developed a correction algorithm to reduce the HTS effect. A built-in microphone and headphone were calibrated to provide the standard units of measure. The HTSs in the presence of either white or babble noise were systematically investigated to determine the mean HTS as a function of noise level. When the hearing screening application runs, the smartphone automatically measures the environmental noise and provides the HTS value to correct the hearing threshold. A comparison to pure tone audiometry shows that this hearing screening method in the presence of noise could closely estimate the hearing threshold. We expect that the proposed ubiquitous hearing test method could be used as a simple hearing screening tool and could alert the user if they suffer from hearing loss.

Hearing loss in children with Fabry disease

NARCIS (Netherlands)

Suntjens, E.; Dreschler, W. A.; Hess-Erga, J.; Skrunes, R.; Wijburg, F. A.; Linthorst, G. E.; Tøndel, C.; Biegstraaten, M.

2017-01-01

Background Hearing loss (HL) is a well-known feature of Fabry disease (FD). Its presence and characteristics have mainly been studied in adult patients, while only limited data are available on the presence and degree of HL in children with FD. This prompted us to study hearing sensitivity in

Synthesis of ZnO tetrapods for flexible and transparent UV sensors

International Nuclear Information System (INIS)

Rackauskas, Simas; Mustonen, Kimmo; Järvinen, Terhi; Jiang, Hua; Kauppinen, Esko I; Nasibulin, Albert G; Mattila, Marco; Lipsanen, Harri; Klimova, Olga; Tolochko, Oleg

2012-01-01

ZnO tetrapods (ZnO-Ts) were synthesized in a vertical flow reactor by gas phase oxidation of Zn vapor in an air atmosphere. The morphology of the product was varied from nearly spherical nanoparticles to ZnO-Ts, together with the partial pressure of Zn and reaction temperature. MgO introduced during synthesis, increased the band gap, the optical transparency in the visible range, and also changed the ZnO-T structure. Fabricated flexible transparent UV sensors showed a 45-fold current increase under UV irradiation with an intensity of 30 μW cm −2 at a wavelength of 365 nm and response time of 0.9 s. (paper)

Field hearing measurements of the Atlantic sharpnose shark Rhizoprionodon terraenovae.

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Casper, B M; Mann, D A

2009-12-01

Field measurements of hearing thresholds were obtained from the Atlantic sharpnose shark Rhizoprionodon terraenovae using the auditory evoked potential method (AEP). The fish had most sensitive hearing at 20 Hz, the lowest frequency tested, with decreasing sensitivity at higher frequencies. Hearing thresholds were lower than AEP thresholds previously measured for the nurse shark Ginglymostoma cirratum and yellow stingray Urobatis jamaicensis at frequencies sharks which have been observed in acoustic field attraction experiments. The sound pressure levels that would be equivalent to the particle acceleration thresholds of R. terraenovae were much higher than the sound levels which attracted closely related sharks suggesting a discrepancy between the hearing threshold experiments and the field attraction experiments.

Comparative anatomy, evolution, and homologies of tetrapod hindlimb muscles, comparison with forelimb muscles, and deconstruction of the forelimb-hindlimb serial homology hypothesis.

Science.gov (United States)

Diogo, Rui; Molnar, Julia

2014-06-01

For more than two centuries, the idea that the forelimb and hindlimb are serially homologous structures has been accepted without serious question. This study presents the first detailed analysis of the evolution and homologies of all hindlimb muscles in representatives of each major tetrapod group and proposes a unifying nomenclature for these muscles. These data are compared with information obtained previously about the forelimb muscles of tetrapods and the muscles of other gnathostomes in order to address one of the most central and enigmatic questions in evolutionary and comparative anatomy: why are the pelvic and pectoral appendages of gnathostomes generally so similar to each other? An integrative analysis of the new myological data, combined with a review of recent paleontological, developmental, and genetic works and of older studies, does not support serial homology between the structures of these appendages. For instance, many of the strikingly similar forelimb and hindlimb muscles found in each major extant tetrapod taxon were acquired at different geological times and/or have different embryonic origins. These similar muscles are not serial homologues, but the result of evolutionary parallelism/convergence due to a complex interplay of ontogenetic, functional, topological, and phylogenetic constraints/factors. Copyright © 2014 Wiley Periodicals, Inc.

Towards Objective Measures of Functional Hearing Abilities

DEFF Research Database (Denmark)

Innes-Brown, Hamish; Tsongas, Renee; Marozeau, Jeremy

2016-01-01

Aims People with impaired hearing often have difficulties in hearing sounds in a noisy background. This problem is partially a result of the auditory systems reduced capacity to process temporal information in the sound signal. In this study we examined the relationships between perceptual...... was positively correlated with TFS sensitivity, and negatively correlated with age. TFS sensitivity was also positively correlated with stimulus encoding accuracy for the complex harmonic stimulus, while increasing age was associated with lower stimulus encoding accuracy for the modulated tone stimulus...

Mismatch between aspects of hearing impairment and hearing disability/handicap in adult/elderly Cantonese speakers: some hypotheses concerning cultural and linguistic influences.

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Doyle, J; Wong, L L

1996-12-01

This paper addresses the observation that some Cantonese-speaking adults do not perceive a hearing problem even when hearing screening identifies hearing loss. A sample of 49 Cantonese speakers was surveyed about their self-perceptions of hearing prior to a 25 dB HTL pure-tone screening test. All 49 persons failed the screening test, yet 34 (69.4%) reported that they had no problems hearing during conversations. Persons who admitted hearing difficulties tended to have mean hearing levels in excess of 45 dB HTL. A number of hypotheses concerning cultural and linguistic influences are proposed as explanations for the apparent lack of significance of auditory sensitivity loss for some Cantonese speakers. Ways in which these hypotheses might be tested are suggested.

Modeling auditory perception of individual hearing-impaired listeners

DEFF Research Database (Denmark)

Jepsen, Morten Løve; Dau, Torsten

showed that, in most cases, the reduced or absent cochlear compression, associated with outer hair-cell loss, quantitatively accounts for broadened auditory filters, while a combination of reduced compression and reduced inner hair-cell function accounts for decreased sensitivity and slower recovery from...... selectivity. Three groups of listeners were considered: (a) normal hearing listeners; (b) listeners with a mild-to-moderate sensorineural hearing loss; and (c) listeners with a severe sensorineural hearing loss. A fixed set of model parameters were derived for each hearing-impaired listener. The simulations...

A carapace-like bony 'body tube' in an early triassic marine reptile and the onset of marine tetrapod predation.

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Chen, Xiao-hong; Motani, Ryosuke; Cheng, Long; Jiang, Da-yong; Rieppel, Olivier

2014-01-01

Parahupehsuchus longus is a new species of marine reptile from the Lower Triassic of Yuan'an County, Hubei Province, China. It is unique among vertebrates for having a body wall that is completely surrounded by a bony tube, about 50 cm long and 6.5 cm deep, comprising overlapping ribs and gastralia. This tube and bony ossicles on the back are best interpreted as anti-predatory features, suggesting that there was predation pressure upon marine tetrapods in the Early Triassic. There is at least one sauropterygian that is sufficiently large to feed on Parahupehsuchus in the Nanzhang-Yuan'an fauna, together with six more species of potential prey marine reptiles with various degrees of body protection. Modern predators of marine tetrapods belong to the highest trophic levels in the marine ecosystem but such predators did not always exist through geologic time. The indication of marine-tetrapod feeding in the Nanzhang-Yuan'an fauna suggests that such a trophic level emerged for the first time in the Early Triassic. The recovery from the end-Permian extinction probably proceeded faster than traditionally thought for marine predators. Parahupehsuchus has superficially turtle-like features, namely expanded ribs without intercostal space, very short transverse processes, and a dorsal outgrowth from the neural spine. However, these features are structurally different from their turtle counterparts. Phylogeny suggests that they are convergent with the condition in turtles, which has a fundamentally different body plan that involves the folding of the body wall. Expanded ribs without intercostal space evolved at least twice and probably even more among reptiles.

A carapace-like bony 'body tube' in an early triassic marine reptile and the onset of marine tetrapod predation.

Directory of Open Access Journals (Sweden)

Xiao-hong Chen

Full Text Available Parahupehsuchus longus is a new species of marine reptile from the Lower Triassic of Yuan'an County, Hubei Province, China. It is unique among vertebrates for having a body wall that is completely surrounded by a bony tube, about 50 cm long and 6.5 cm deep, comprising overlapping ribs and gastralia. This tube and bony ossicles on the back are best interpreted as anti-predatory features, suggesting that there was predation pressure upon marine tetrapods in the Early Triassic. There is at least one sauropterygian that is sufficiently large to feed on Parahupehsuchus in the Nanzhang-Yuan'an fauna, together with six more species of potential prey marine reptiles with various degrees of body protection. Modern predators of marine tetrapods belong to the highest trophic levels in the marine ecosystem but such predators did not always exist through geologic time. The indication of marine-tetrapod feeding in the Nanzhang-Yuan'an fauna suggests that such a trophic level emerged for the first time in the Early Triassic. The recovery from the end-Permian extinction probably proceeded faster than traditionally thought for marine predators. Parahupehsuchus has superficially turtle-like features, namely expanded ribs without intercostal space, very short transverse processes, and a dorsal outgrowth from the neural spine. However, these features are structurally different from their turtle counterparts. Phylogeny suggests that they are convergent with the condition in turtles, which has a fundamentally different body plan that involves the folding of the body wall. Expanded ribs without intercostal space evolved at least twice and probably even more among reptiles.

Distinction of neurochemistry between the cores and their shells of auditory nuclei in tetrapod species.

Science.gov (United States)

Zeng, ShaoJu; Li, Jia; Zhang, XinWen; Zuo, MingXue

2007-01-01

The distribution of Met-enkephalin (ENK), substance P (SP) and serotonin (5-HT) differs between the core and shell regions of the mesencephalic and diencephalic auditory nuclei of the turtle [Belekhova et al., 2002]. These neurochemical distinctions are also found in other tetrapods (mammals, birds and amphibians). The distribution of ENK, SP and 5-HT was examined in the core and shell regions of both mesencephalic and diencephalic auditory nuclei, and in the telencephalic auditory areas of Bengalese finches (Lonchura striata) and mice (Mus musculus), as well as in corresponding auditory areas in toads (Bufo bufo). ENK, SP and 5-HT immunoreactive fibers and perikarya were largely absent from the core regions of both mesencephalic and diencephalic auditory nuclei, in comparison with the shell regions of mice and Bengalese finches. In the toad, however, this pattern was observed in the mesencephalic auditory nucleus, but not in the diencephalic auditory areas. ENK and SP immunoreactive perikarya were detected in the telencephalic auditory area of mice, whereas no ENK, SP or 5-HT immunolabeling was observed in the telencephalic auditory area (Field L) of Bengalese finches. These findings are discussed in terms of the evolution of the core-and-shell organization of auditory nuclei of tetrapods. Copyright 2007 S. Karger AG, Basel.

Joining the un-joinable: adhesion between low surface energy polymers using tetrapodal ZnO linkers.

Science.gov (United States)

Jin, Xin; Strueben, Jan; Heepe, Lars; Kovalev, Alexander; Mishra, Yogendra K; Adelung, Rainer; Gorb, Stanislav N; Staubitz, Anne

2012-11-08

Tetrapodal ZnO crystals are used for mechanical interlocking of PTFE and cross-linked PDMS, classically non-adhesive polymers. This novel approach is straightforward and easily applicable and leads to a peel strength that is higher than 200 N m(-1) without chemical modification of the surfaces. The shape of these fillers emerged as a crucial aspect of the interlocking mechanism. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Statistical model for prediction of hearing loss in patients receiving cisplatin chemotherapy.

Science.gov (United States)

Johnson, Andrew; Tarima, Sergey; Wong, Stuart; Friedland, David R; Runge, Christina L

2013-03-01

This statistical model might be used to predict cisplatin-induced hearing loss, particularly in patients undergoing concomitant radiotherapy. To create a statistical model based on pretreatment hearing thresholds to provide an individual probability for hearing loss from cisplatin therapy and, secondarily, to investigate the use of hearing classification schemes as predictive tools for hearing loss. Retrospective case-control study. Tertiary care medical center. A total of 112 subjects receiving chemotherapy and audiometric evaluation were evaluated for the study. Of these subjects, 31 met inclusion criteria for analysis. The primary outcome measurement was a statistical model providing the probability of hearing loss following the use of cisplatin chemotherapy. Fifteen of the 31 subjects had significant hearing loss following cisplatin chemotherapy. American Academy of Otolaryngology-Head and Neck Society and Gardner-Robertson hearing classification schemes revealed little change in hearing grades between pretreatment and posttreatment evaluations for subjects with or without hearing loss. The Chang hearing classification scheme could effectively be used as a predictive tool in determining hearing loss with a sensitivity of 73.33%. Pretreatment hearing thresholds were used to generate a statistical model, based on quadratic approximation, to predict hearing loss (C statistic = 0.842, cross-validated = 0.835). The validity of the model improved when only subjects who received concurrent head and neck irradiation were included in the analysis (C statistic = 0.91). A calculated cutoff of 0.45 for predicted probability has a cross-validated sensitivity and specificity of 80%. Pretreatment hearing thresholds can be used as a predictive tool for cisplatin-induced hearing loss, particularly with concomitant radiotherapy.

Comparative pelvic development of the axolotl (Ambystoma mexicanum) and the Australian lungfish (Neoceratodus forsteri): conservation and innovation across the fish-tetrapod transition.

Science.gov (United States)

Boisvert, Catherine Anne; Joss, Jean Mp; Ahlberg, Per E

2013-01-23

The fish-tetrapod transition was one of the major events in vertebrate evolution and was enabled by many morphological changes. Although the transformation of paired fish fins into tetrapod limbs has been a major topic of study in recent years, both from paleontological and comparative developmental perspectives, the interest has focused almost exclusively on the distal part of the appendage and in particular the origin of digits. Relatively little attention has been paid to the transformation of the pelvic girdle from a small unipartite structure to a large tripartite weight-bearing structure, allowing tetrapods to rely mostly on their hindlimbs for locomotion. In order to understand how the ischium and the ilium evolved and how the acetabulum was reoriented during this transition, growth series of the Australian lungfish Neoceratodus forsteri and the Mexican axolotl Ambystoma mexicanum were cleared and stained for cartilage and bone and immunostained for skeletal muscles. In order to understand the myological developmental data, hypotheses about the homologies of pelvic muscles in adults of Latimeria, Neoceratodus and Necturus were formulated based on descriptions from the literature of the coelacanth (Latimeria), the Australian Lungfish (Neoceratodus) and a salamander (Necturus). In the axolotl and the lungfish, the chondrification of the pelvic girdle starts at the acetabula and progresses anteriorly in the lungfish and anteriorly and posteriorly in the salamander. The ilium develops by extending dorsally to meet and connect to the sacral rib in the axolotl. Homologous muscles develop in the same order with the hypaxial musculature developing first, followed by the deep, then the superficial pelvic musculature. Development of the pelvic endoskeleton and musculature is very similar in Neoceratodus and Ambystoma. If the acetabulum is seen as being a fixed landmark, the evolution of the ischium only required pubic pre-chondrogenic cells to migrate posteriorly. It

A Carapace-Like Bony ‘Body Tube’ in an Early Triassic Marine Reptile and the Onset of Marine Tetrapod Predation

Science.gov (United States)

Chen, Xiao-hong; Motani, Ryosuke; Cheng, Long; Jiang, Da-yong; Rieppel, Olivier

2014-01-01

Parahupehsuchus longus is a new species of marine reptile from the Lower Triassic of Yuan’an County, Hubei Province, China. It is unique among vertebrates for having a body wall that is completely surrounded by a bony tube, about 50 cm long and 6.5 cm deep, comprising overlapping ribs and gastralia. This tube and bony ossicles on the back are best interpreted as anti-predatory features, suggesting that there was predation pressure upon marine tetrapods in the Early Triassic. There is at least one sauropterygian that is sufficiently large to feed on Parahupehsuchus in the Nanzhang-Yuan’an fauna, together with six more species of potential prey marine reptiles with various degrees of body protection. Modern predators of marine tetrapods belong to the highest trophic levels in the marine ecosystem but such predators did not always exist through geologic time. The indication of marine-tetrapod feeding in the Nanzhang-Yuan’an fauna suggests that such a trophic level emerged for the first time in the Early Triassic. The recovery from the end-Permian extinction probably proceeded faster than traditionally thought for marine predators. Parahupehsuchus has superficially turtle-like features, namely expanded ribs without intercostal space, very short transverse processes, and a dorsal outgrowth from the neural spine. However, these features are structurally different from their turtle counterparts. Phylogeny suggests that they are convergent with the condition in turtles, which has a fundamentally different body plan that involves the folding of the body wall. Expanded ribs without intercostal space evolved at least twice and probably even more among reptiles. PMID:24718682

Four odontocete species change hearing levels when warned of impending loud sound.

Science.gov (United States)

Nachtigall, Paul E; Supin, Alexander Ya; Pacini, Aude F; Kastelein, Ronald A

2018-03-01

Hearing sensitivity change was investigated when a warning sound preceded a loud sound in the false killer whale (Pseudorca crassidens), the bottlenose dolphin (Tursiops truncatus), the beluga whale (Delphinaperus leucas) and the harbor porpoise (Phocoena phocoena). Hearing sensitivity was measured using pip-train test stimuli and auditory evoked potential recording. When the test/warning stimuli preceded a loud sound, hearing thresholds before the loud sound increased relative to the baseline by 13 to 17 dB. Experiments with multiple frequencies of exposure and shift provided evidence of different amounts of hearing change depending on frequency, indicating that the hearing sensation level changes were not likely due to a simple stapedial reflex. © 2017 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

Music exposure and hearing disorders: an overview.

Science.gov (United States)

Zhao, Fei; Manchaiah, Vinaya K C; French, David; Price, Sharon M

2010-01-01

It has been generally accepted that excessive exposure to loud music causes various hearing symptoms (e.g. tinnitus) and consequently leads to a risk of permanent hearing damage, known as noise-induced hearing loss (NIHL). Such potential risk of NIHL due to loud music exposure has been widely investigated in musicians and people working in music venues. With advancements in sound technology and rapid developments in the music industry, increasing numbers of people, particularly adolescents and young adults, are exposing themselves to music on a voluntary basis at potentially harmful levels, and over a substantial period of time, which can also cause NIHL. However, because of insufficient audiometric evidence of hearing loss caused purely by music exposure, there is still disagreement and speculation about the risk of hearing loss from music exposure alone. Many studies have suggested using advanced audiological measurements as more sensitive and efficient tools to monitor hearing status as early indicators of cochlear dysfunction. The purpose of this review is to provide further insight into the potential risk of hearing loss caused by exposure to loud music, and thus contribute to further raising awareness of music induced hearing loss.

Diverse tetrapod trackways in the Lower Pennsylvanian Tynemouth Creek Formation, near St. Martins, southern New Brunswick, Canada

DEFF Research Database (Denmark)

Falcon-Lang, Howard J.; Gibling, Martin R.; Benton, Michael J.

2010-01-01

Newly discovered tetrapod trackways are reported from eight sites in the Lower Pennsylvanian Tynemouth Creek Formation of southern New Brunswick, Canada. By far the most abundant and well-preserved tracks comprise pentadactyl footprints of medium size (32–53 mm long) with slender digits and a nar......Newly discovered tetrapod trackways are reported from eight sites in the Lower Pennsylvanian Tynemouth Creek Formation of southern New Brunswick, Canada. By far the most abundant and well-preserved tracks comprise pentadactyl footprints of medium size (32–53 mm long) with slender digits...... and a narrow splay (mostly b55°). Digit lengths typically approximate a phalangeal formula of 23453 (manus) and 23454 (pes), but this may vary due to extramorphology. These tracks are referred to Pseudobradypus and they are attributed to early amniotes. A second type of track (rare) comprises very small (5......–8 mm long) tetradactyl manus, and incompletely preserved pedes. Referred to Batrachichnus, these are attributed to temnospondyl amphibians. A third type (also rare) comprises small pentadactyl pedes (20–25 mm long) showing stubby, widely splayed (152°) digits with a terminal bulge. Manus are probably...

Binaural hearing with electrical stimulation

Science.gov (United States)

Kan, Alan; Litovsky, Ruth Y.

2014-01-01

Bilateral cochlear implantation is becoming a standard of care in many clinics. While much benefit has been shown through bilateral implantation, patients who have bilateral cochlear implants (CIs) still do not perform as well as normal hearing listeners in sound localization and understanding speech in noisy environments. This difference in performance can arise from a number of different factors, including the areas of hardware and engineering, surgical precision and pathology of the auditory system in deaf persons. While surgical precision and individual pathology are factors that are beyond careful control, improvements can be made in the areas of clinical practice and the engineering of binaural speech processors. These improvements should be grounded in a good understanding of the sensitivities of bilateral CI patients to the acoustic binaural cues that are important to normal hearing listeners for sound localization and speech in noise understanding. To this end, we review the current state-of-the-art in the understanding of the sensitivities of bilateral CI patients to binaural cues in electric hearing, and highlight the important issues and challenges as they relate to clinical practice and the development of new binaural processing strategies. PMID:25193553

Unilateral hearing during development: hemispheric specificity in plastic reorganizations

Directory of Open Access Journals (Sweden)

Andrej eKral

2013-11-01

Full Text Available The present study investigates the hemispheric contributions of neuronal reorganization following early single-sided hearing (unilateral deafness. The experiments were performed on ten cats from our colony of deaf white cats. Two were identified in early hearing screening as unilaterally congenitally deaf. The remaining eight were bilaterally congenitally deaf, unilaterally implanted at different ages with a cochlear implant. Implanted animals were chronically stimulated using a single-channel portable signal processor for two to five months. Microelectrode recordings were performed at the primary auditory cortex under stimulation at the hearing and deaf ear with bilateral cochlear implants. Local field potentials (LFPs were compared at the cortex ipsilateral and contralateral to the hearing ear. The focus of the study was on the morphology and the onset latency of the LFPs. The data revealed that effects of hearing experience were more pronounced when stimulating the hearing ear. With respect to morphology of LFPs, pronounced hemisphere-specific effects were observed. Morphology of amplitude-normalized LFPs for stimulation of the deaf and the hearing ear was similar for responses recorded at the same hemisphere. However, when comparisons were performed between the hemispheres, the morphology was more dissimilar even though the same ear was stimulated. This demonstrates hemispheric specificity of some cortical adaptations irrespective of the ear stimulated. The results suggest a specific adaptation process at the hemisphere ipsilateral to the hearing ear, involving specific (down-regulated inhibitory mechanisms not found in the contralateral hemisphere. Finally, onset latencies revealed that the sensitive period for the cortex ipsilateral to the hearing ear is shorter than that for the contralateral cortex. Unilateral hearing experience leads to a functionally-asymmetric brain with different neuronal reorganizations and different sensitive

The cormorant ear – an adaptation to underwater hearing?

DEFF Research Database (Denmark)

Larsen, Ole Næsbye; Wahlberg, Magnus; Christensen-Dalsgaard, Jakob

Depending on species, diving birds may spend 2-20 minutes under water during a single foraging dive when they may reach depths ranging from one to several hundred meters. Surprisingly little is known about avian underwater hearing despite the fact that several hundred species dive for food. We do...... was similar to that reported for birds of the same size in air. The bandwidth and slopes of the audiograms were similar in air and water. However, in air the highest sensitivity was found at 1-2 kHz, whereas it was displaced towards lower frequencies under water. These results suggest that cormorants have...... rather poor in-air hearing compared to similar-sized birds. Their underwater hearing sensitivity, however, is higher than what would have been expected for purely air-adapted ears. A possible reason for the poor in-air sensitivity is the special ear anatomy with the central eardrum shaped as a rigid...

Sensitivity to Conversational Maxims in Deaf and Hearing Children

Science.gov (United States)

Surian, Luca; Tedoldi, Mariantonia; Siegel, Michael

2010-01-01

We investigated whether access to a sign language affects the development of pragmatic competence in three groups of deaf children aged 6 to 11 years: native signers from deaf families receiving bimodal/bilingual instruction, native signers from deaf families receiving oralist instruction and late signers from hearing families receiving oralist…

High-frequency audiometry: A means for early diagnosis of noise-induced hearing loss

Directory of Open Access Journals (Sweden)

Amir H Mehrparvar

2011-01-01

Full Text Available Noise-induced hearing loss (NIHL, an irreversible disorder, is a common problem in industrial settings. Early diagnosis of NIHL can help prevent the progression of hearing loss, especially in speech frequencies. For early diagnosis of NIHL, audiometry is performed routinely in conventional frequencies. We designed this study to compare the effect of noise on high-frequency audiometry (HFA and conventional audiometry. In a historical cohort study, we compared hearing threshold and prevalence of hearing loss in conventional and high frequencies of audiometry among textile workers divided into two groups: With and without exposure to noise more than 85 dB. The highest hearing threshold was observed at 4000 Hz, 6000 Hz and 16000 Hz in conventional right ear audiometry, conventional left ear audiometry and HFA in each ear, respectively. The hearing threshold was significantly higher at 16000 Hz compared to 4000. Hearing loss was more common in HFA than conventional audiometry. HFA is more sensitive to detect NIHL than conventional audiometry. It can be useful for early diagnosis of hearing sensitivity to noise, and thus preventing hearing loss in lower frequencies especially speech frequencies.

Tetrapods on the EDGE: Overcoming data limitations to identify phylogenetic conservation priorities

Science.gov (United States)

Gray, Claudia L.; Wearn, Oliver R.; Owen, Nisha R.

2018-01-01

The scale of the ongoing biodiversity crisis requires both effective conservation prioritisation and urgent action. As extinction is non-random across the tree of life, it is important to prioritise threatened species which represent large amounts of evolutionary history. The EDGE metric prioritises species based on their Evolutionary Distinctiveness (ED), which measures the relative contribution of a species to the total evolutionary history of their taxonomic group, and Global Endangerment (GE), or extinction risk. EDGE prioritisations rely on adequate phylogenetic and extinction risk data to generate meaningful priorities for conservation. However, comprehensive phylogenetic trees of large taxonomic groups are extremely rare and, even when available, become quickly out-of-date due to the rapid rate of species descriptions and taxonomic revisions. Thus, it is important that conservationists can use the available data to incorporate evolutionary history into conservation prioritisation. We compared published and new methods to estimate missing ED scores for species absent from a phylogenetic tree whilst simultaneously correcting the ED scores of their close taxonomic relatives. We found that following artificial removal of species from a phylogenetic tree, the new method provided the closest estimates of their “true” ED score, differing from the true ED score by an average of less than 1%, compared to the 31% and 38% difference of the previous methods. The previous methods also substantially under- and over-estimated scores as more species were artificially removed from a phylogenetic tree. We therefore used the new method to estimate ED scores for all tetrapods. From these scores we updated EDGE prioritisation rankings for all tetrapod species with IUCN Red List assessments, including the first EDGE prioritisation for reptiles. Further, we identified criteria to identify robust priority species in an effort to further inform conservation action whilst

Vestibular hearing and neural synchronization.

Science.gov (United States)

Emami, Seyede Faranak; Daneshi, Ahmad

2012-01-01

Objectives. Vestibular hearing as an auditory sensitivity of the saccule in the human ear is revealed by cervical vestibular evoked myogenic potentials (cVEMPs). The range of the vestibular hearing lies in the low frequency. Also, the amplitude of an auditory brainstem response component depends on the amount of synchronized neural activity, and the auditory nerve fibers' responses have the best synchronization with the low frequency. Thus, the aim of this study was to investigate correlation between vestibular hearing using cVEMPs and neural synchronization via slow wave Auditory Brainstem Responses (sABR). Study Design. This case-control survey was consisted of twenty-two dizzy patients, compared to twenty healthy controls. Methods. Intervention comprised of Pure Tone Audiometry (PTA), Impedance acoustic metry (IA), Videonystagmography (VNG), fast wave ABR (fABR), sABR, and cVEMPs. Results. The affected ears of the dizzy patients had the abnormal findings of cVEMPs (insecure vestibular hearing) and the abnormal findings of sABR (decreased neural synchronization). Comparison of the cVEMPs at affected ears versus unaffected ears and the normal persons revealed significant differences (P < 0.05). Conclusion. Safe vestibular hearing was effective in the improvement of the neural synchronization.

Spectrotemporal modulation sensitivity for hearing-impaired listeners: dependence on carrier center frequency and the relationship to speech intelligibility.

Science.gov (United States)

Mehraei, Golbarg; Gallun, Frederick J; Leek, Marjorie R; Bernstein, Joshua G W

2014-07-01

Poor speech understanding in noise by hearing-impaired (HI) listeners is only partly explained by elevated audiometric thresholds. Suprathreshold-processing impairments such as reduced temporal or spectral resolution or temporal fine-structure (TFS) processing ability might also contribute. Although speech contains dynamic combinations of temporal and spectral modulation and TFS content, these capabilities are often treated separately. Modulation-depth detection thresholds for spectrotemporal modulation (STM) applied to octave-band noise were measured for normal-hearing and HI listeners as a function of temporal modulation rate (4-32 Hz), spectral ripple density [0.5-4 cycles/octave (c/o)] and carrier center frequency (500-4000 Hz). STM sensitivity was worse than normal for HI listeners only for a low-frequency carrier (1000 Hz) at low temporal modulation rates (4-12 Hz) and a spectral ripple density of 2 c/o, and for a high-frequency carrier (4000 Hz) at a high spectral ripple density (4 c/o). STM sensitivity for the 4-Hz, 4-c/o condition for a 4000-Hz carrier and for the 4-Hz, 2-c/o condition for a 1000-Hz carrier were correlated with speech-recognition performance in noise after partialling out the audiogram-based speech-intelligibility index. Poor speech-reception and STM-detection performance for HI listeners may be related to a combination of reduced frequency selectivity and a TFS-processing deficit limiting the ability to track spectral-peak movements.

Do Hearing Protectors Protect Hearing?

Science.gov (United States)

Groenewold, Matthew R.; Masterson, Elizabeth A.; Themann, Christa L.; Davis, Rickie R.

2015-01-01

Background We examined the association between self-reported hearing protection use at work and incidence of hearing shifts over a 5-year period. Methods Audiometric data from 19,911 workers were analyzed. Two hearing shift measures—OSHA standard threshold shift (OSTS) and high-frequency threshold shift (HFTS)—were used to identify incident shifts in hearing between workers’ 2005 and 2009 audiograms. Adjusted odds ratios were generated using multivariable logistic regression with multi-level modeling. Results The odds ratio for hearing shift for workers who reported never versus always wearing hearing protection was nonsignificant for OSTS (OR 1.23, 95% CI 0.92–1.64) and marginally significant for HFTS (OR 1.26, 95% CI 1.00–1.59). A significant linear trend towards increased risk of HFTS with decreased use of hearing protection was observed (P = 0.02). Conclusion The study raises concern about the effectiveness of hearing protection as a substitute for noise control to prevent noise-induced hearing loss in the workplace. Am. J. Ind. Med. 57:1001–1010, 2014. Published 2014. This article is a U.S. Government work and is in the public domain in the USA. PMID:24700499

Unilateral hearing during development: hemispheric specificity in plastic reorganizations.

Science.gov (United States)

Kral, Andrej; Heid, Silvia; Hubka, Peter; Tillein, Jochen

2013-01-01

The present study investigates the hemispheric contributions of neuronal reorganization following early single-sided hearing (unilateral deafness). The experiments were performed on ten cats from our colony of deaf white cats. Two were identified in early hearing screening as unilaterally congenitally deaf. The remaining eight were bilaterally congenitally deaf, unilaterally implanted at different ages with a cochlear implant. Implanted animals were chronically stimulated using a single-channel portable signal processor for two to five months. Microelectrode recordings were performed at the primary auditory cortex under stimulation at the hearing and deaf ear with bilateral cochlear implants. Local field potentials (LFPs) were compared at the cortex ipsilateral and contralateral to the hearing ear. The focus of the study was on the morphology and the onset latency of the LFPs. With respect to morphology of LFPs, pronounced hemisphere-specific effects were observed. Morphology of amplitude-normalized LFPs for stimulation of the deaf and the hearing ear was similar for responses recorded at the same hemisphere. However, when comparisons were performed between the hemispheres, the morphology was more dissimilar even though the same ear was stimulated. This demonstrates hemispheric specificity of some cortical adaptations irrespective of the ear stimulated. The results suggest a specific adaptation process at the hemisphere ipsilateral to the hearing ear, involving specific (down-regulated inhibitory) mechanisms not found in the contralateral hemisphere. Finally, onset latencies revealed that the sensitive period for the cortex ipsilateral to the hearing ear is shorter than that for the contralateral cortex. Unilateral hearing experience leads to a functionally-asymmetric brain with different neuronal reorganizations and different sensitive periods involved.

Synthesis, structure and luminescence properties of lanthanide complex with a new tetrapodal ligand featuring salicylamide arms

International Nuclear Information System (INIS)

Song Xueqin; Wen Xiaoguang; Liu Weisheng; Wang Daqi

2010-01-01

A new tetrapodal ligand 1,1,1-tetrakis{[(2'-(2-furfurylaminoformyl))phenoxyl]methyl}methane (L) has been prepared and their coordination chemistry with Ln III ions has been investigated. The structure of {[Ln 4 L 3 (NO 3 ) 12 ].H 2 O} ∞ (Ln=Nd, Eu)] shows the binodal 4,3-connected three-dimensional interpenetration coordination polymers with topology of a (8 6 ) 3 (8 3 ) 4 notation. [DyL(NO 3 ) 3 (H 2 O) 2 ].0.5CH 3 OH and [ErL(NO 3 ) 3 (H 2 O) (CH 3 OH)].CH 3 COCH 3 is a 1:1 mononuclear complex with interesting supramolecular features. The structure of [NdL(H 2 O) 6 ].3ClO 4 .3H 2 O is a 2:1 mononuclear complex which further self-assembled through hydrogen bond to form a three-dimensional supramolecular structures. The result presented here indicates that both subtle variation of the terminal group and counter anions can be applied in the modulation of the overall molecular structures of lanthanide complex of salicylamide derivatives due to the structure specialties of this type of ligand. The luminescence properties of the Eu III complex are also studied in detail. - Grapical Abstract: We present here a series of zero- to three-dimensional lanthanide coordination structures and luminescence properties of Eu(III) complex of a new tetrapodal ligand.

Development of vocalization and hearing in American mink (Neovison vison)

DEFF Research Database (Denmark)

Brandt, Christian; Malmkvist, Jens; Nielsen, Rasmus L.

2013-01-01

-tested (P=0.004). Large numbers of mink are kept in fur industry farms, and our results are important to the understanding of sound communication, which is part of their natural behaviour. Our results also suggest mink as an interesting model for studying the development of mammalian hearing and its......American mink (Neovison vison) kits are born altricial and fully dependent on maternal care, for which the kits’ vocalizations appear essential. We used auditory brainstem responses (ABRs) to determine: (1) hearing sensitivity of adult females from two breeding lines known to differ in maternal...... behaviour and (2) development of hearing in kits 8–52days of age. We also studied sound production in 20 kits throughout postnatal days 1 to 44. Adult female mink had a broad hearing range from 1kHz to above 70kHz, with peak sensitivity (threshold of 20dB SPL) at 8–10kHz, and no difference...

Binaural hearing with electrical stimulation.

Science.gov (United States)

Kan, Alan; Litovsky, Ruth Y

2015-04-01

Bilateral cochlear implantation is becoming a standard of care in many clinics. While much benefit has been shown through bilateral implantation, patients who have bilateral cochlear implants (CIs) still do not perform as well as normal hearing listeners in sound localization and understanding speech in noisy environments. This difference in performance can arise from a number of different factors, including the areas of hardware and engineering, surgical precision and pathology of the auditory system in deaf persons. While surgical precision and individual pathology are factors that are beyond careful control, improvements can be made in the areas of clinical practice and the engineering of binaural speech processors. These improvements should be grounded in a good understanding of the sensitivities of bilateral CI patients to the acoustic binaural cues that are important to normal hearing listeners for sound localization and speech in noise understanding. To this end, we review the current state-of-the-art in the understanding of the sensitivities of bilateral CI patients to binaural cues in electric hearing, and highlight the important issues and challenges as they relate to clinical practice and the development of new binaural processing strategies. This article is part of a Special Issue entitled . Copyright © 2014 Elsevier B.V. All rights reserved.

Comparative anatomy, homologies and evolution of the pectoral and forelimb musculature of tetrapods with special attention to extant limbed amphibians and reptiles.

Science.gov (United States)

Abdala, Virginia; Diogo, Rui

2010-11-01

The main aim of the present work is to synthesize the information obtained from our dissections of the pectoral and forelimb muscles of representative members of the major extant taxa of limbed amphibians and reptiles and from our review of the literature, in order to provide an account of the comparative anatomy, homologies and evolution of these muscles in the Tetrapoda. The pectoral and forelimb musculature of all these major taxa conform to a general pattern that seems to have been acquired very early in the evolutionary history of tetrapods. Although some muscles are missing in certain taxa, and a clear departure from this general pattern is obviously present in derived groups such as birds, the same overall configuration is easily distinguishable in these taxa. Among the most notable anatomical differences between the groups, one that seems to have relevant evolutionary and functional implications, concerns the distal insertion points of the forearm musculature. In tetrapods, the muscles of the radial and ulnar complexes of the forearm are pleisomorphically mainly inserted onto the radius/ulna or onto the more proximal carpal bones, but in mammals some of these muscles insert more distally onto bones such as the metacarpals. Interestingly, a similar trend towards a more distal insertion of these muscles is also found in some non-mammalian tetrapod taxa, such as some anurans (e.g. Phyllomedusa). This may be correlated with the acquisition of more subtle digital movement abilities in these latter taxa. © 2010 The Authors. Journal of Anatomy © 2010 Anatomical Society of Great Britain and Ireland.

[Hearing loss and idoneity--the segnalation of noise-induced hearing loss hearing Loss].

Science.gov (United States)

Albera, Roberto; Dagna, Federico; Cassandro, Claudia; Canale, Andrea

2011-01-01

Work idoneity in hearing loss must be related to working ability and evolution risks. Working ability is referred to the difficulties found in speech comprehension and in signals perception. As regards hearing loss evolution it is necessary to define if the subject is affected by conductive or neurosensorial hearing loss. In conductive hearing loss it is necessary to evaluate entity and frequential distribution of the deficit. In neurosensorial hearing loss it is necessary to distinguish between noise-induced hearing loss and extraprofessional hearing loss. In noise-induced hearing loss the evolution risk is high if the noise exposure is less than 10-15 years or the actual noise exposure is louder than the former. In case of extraprofessional hearing loss the evolution risk is higher in presbycusis, endolymphatic hydrops and toxic hearing loss. The necessity to report the presence on professionale noise-induced hearing loss arises if audiometric threshold is more than 25 dB at 0.5-1-2-3-4 kHz and if it is verified the professional origine of hearing loss.

Visual function and ocular status of children with hearing impairment in Oman: A case series

Directory of Open Access Journals (Sweden)

Khandekar Rajiv

2009-01-01

Full Text Available Visual functions of children with hearing disability were evaluated in a school of Muscat, Oman in 2006. Two hundred and twenty-three children were tested for near vision, distant vision, contrast sensitivity, color vision, field of vision, motion perception and crowding. Profound and severe hearing loss was noted in 161 and 63 students respectively. Thirty-five (81% students with refractive error were using spectacles. Color vision and field of vision was defective in one student each. In 286 (64.1% eyes, contrast sensitivity was defective. Abnormal contrast sensitivity was not associated with the severity of hearing loss [RR = 1.04 (95% CI 0.91 to 1.29]. Children with hearing impairment should be assessed for visual functions. Refractive error and defect in contrast sensitivity were unusually high among these children. In addition to visual aids, we recommend environmental changes to improve illumination and contrast to improve the quality of life of such children with double disability.

In-air and underwater hearing of the cormorant

DEFF Research Database (Denmark)

Larsen, Ole Næsbye; Wahlberg, Magnus; Christensen-Dalsgaard, Jakob

Numerous studies have mapped the hearing abilities of birds in air but currently there is little or no data on how diving birds hear or react to sound under water. Therefore, it is unknown whether the ears and auditory system of diving birds are adapted to underwater hearing. In the present study...... 10 cm under water in a large water filled-tank while being artificially ventilated. ABR-responses to calibrated tone bursts produced by a woofer and an underwater speaker, respectively, were measured at different intensities and frequencies to obtain hearing threshold values in air and under water......Hz) under water. Generally, the cormorant ear was not very sensitive to sound, neither in air nor under water. The hearing abilities in water, however, were better than what would have been expected for a purely in-air adapted ear. (Supported by the Carlsberg Foundation 2009_01_0292 and the Danish Council...

The influence of military service on auditory health and the efficacy of a hearing conservation program

Directory of Open Access Journals (Sweden)

Per Muhr

2011-01-01

Full Text Available The influence of military service on self-assessed hearing symptoms and measured auditory function was studied as well as the efficacy of the Hearing Conservation Program (HCP of the Swedish Armed Forces. 839 conscripts were recruited for the study at reporting to military service. They were all exposed to noise over the risk-limits from weapons and vehicles and used earmuffs and/or earplugs. Questionnaires and pure tone screening audiometry were studied at the start and the end of the military service. Retrospective information regarding audiometry at conscription before military service was included as control. The prevalence values of tinnitus were 23% before and 32% after the service and of sensitivity to noise 16% and 19% respectively. The prevalence values of hearing impairment were 6.3% at conscription, 14.5% at reporting to military service, and 24% after the training period. The incidence values of hearing decline were 3.7% during the period with no military noise exposure and 6.6% during the military service. Acoustic accident increased the risk of worsened tinnitus and sensitivity to noise four times and for a high frequency hearing decline six times. We observed elevated prevalence values of tinnitus, sensitivity to noise and hearing impairment at discharge compared to before military service. We observed an elevated risk of hearing decline during military service. Acoustic accident increased the risk of tinnitus, noise sensitivity and hearing decline. We suggest improvements regarding inclusion criteria for military service, and for education regarding the HCP.

Auditory Steady-State Response Thresholds in Adults With Conductive and Mild to Moderate Sensorineural Hearing Loss

OpenAIRE

Hosseinabadi, Reza; Jafarzadeh, Sadegh

2014-01-01

Background: The Auditory steady state response (ASSR) provides a frequency-specific and automatic assessment of hearing sensitivity and is used in infants and difficult-to-test adults. Objectives: The aim of this study was to compare the ASSR thresholds among various types (normal, conductive, and sensorineural), degree (normal, mild, and moderate), and configuration (flat and sloping) of hearing sensitivity, and measuring the cutoff point between normal condition and hearing loss for differe...

Study of Tetrapodal ZnO-PDMS Composites: A Comparison of Fillers Shapes in Stiffness and Hydrophobicity Improvements

OpenAIRE

Jin, Xin; Deng, Mao; Kaps, Sören; Zhu, Xinwei; Hölken, Iris; Mess, Kristin; Adelung, Rainer; Mishra, Yogendra Kumar

2014-01-01

ZnO particles of different size and structures were used as fillers to modify the silicone rubber, in order to reveal the effect of the filler shape in the polymer composites. Tetrapodal shaped microparticles, short microfibers/whiskers, and nanosized spherical particles from ZnO have been used as fillers to fabricate the different ZnO-Silicone composites. The detailed microstructures of the fillers as well as synthesized composites using scanning electron microscopy have been presented here....

Hearing aid fitting in older persons with hearing impairment: the influence of cognitive function, age, and hearing loss on hearing aid benefit.

Science.gov (United States)

Meister, Hartmut; Rählmann, Sebastian; Walger, Martin; Margolf-Hackl, Sabine; Kießling, Jürgen

2015-01-01

To examine the association of cognitive function, age, and hearing loss with clinically assessed hearing aid benefit in older hearing-impaired persons. Hearing aid benefit was assessed using objective measures regarding speech recognition in quiet and noisy environments as well as a subjective measure reflecting everyday situations captured using a standardized questionnaire. A broad range of general cognitive functions such as attention, memory, and intelligence were determined using different neuropsychological tests. Linear regression analyses were conducted with the outcome of the neuropsychological tests as well as age and hearing loss as independent variables and the benefit measures as dependent variables. Thirty experienced older hearing aid users with typical age-related hearing impairment participated. Most of the benefit measures revealed that the participants obtained significant improvement with their hearing aids. Regression models showed a significant relationship between a fluid intelligence measure and objective hearing aid benefit. When individual hearing thresholds were considered as an additional independent variable, hearing loss was the only significant contributor to the benefit models. Lower cognitive capacity - as determined by the fluid intelligence measure - was significantly associated with greater hearing loss. Subjective benefit could not be predicted by any of the variables considered. The present study does not give evidence that hearing aid benefit is critically associated with cognitive function in experienced hearing aid users. However, it was found that lower fluid intelligence scores were related to higher hearing thresholds. Since greater hearing loss was associated with a greater objective benefit, these results strongly support the advice of using hearing aids regardless of age and cognitive function to counter hearing loss and the adverse effects of age-related hearing impairment. Still, individual cognitive capacity might

Whole-genome sequence of the Tibetan frog Nanorana parkeri and the comparative evolution of tetrapod genomes.

Science.gov (United States)

Sun, Yan-Bo; Xiong, Zi-Jun; Xiang, Xue-Yan; Liu, Shi-Ping; Zhou, Wei-Wei; Tu, Xiao-Long; Zhong, Li; Wang, Lu; Wu, Dong-Dong; Zhang, Bao-Lin; Zhu, Chun-Ling; Yang, Min-Min; Chen, Hong-Man; Li, Fang; Zhou, Long; Feng, Shao-Hong; Huang, Chao; Zhang, Guo-Jie; Irwin, David; Hillis, David M; Murphy, Robert W; Yang, Huan-Ming; Che, Jing; Wang, Jun; Zhang, Ya-Ping

2015-03-17

The development of efficient sequencing techniques has resulted in large numbers of genomes being available for evolutionary studies. However, only one genome is available for all amphibians, that of Xenopus tropicalis, which is distantly related from the majority of frogs. More than 96% of frogs belong to the Neobatrachia, and no genome exists for this group. This dearth of amphibian genomes greatly restricts genomic studies of amphibians and, more generally, our understanding of tetrapod genome evolution. To fill this gap, we provide the de novo genome of a Tibetan Plateau frog, Nanorana parkeri, and compare it to that of X. tropicalis and other vertebrates. This genome encodes more than 20,000 protein-coding genes, a number similar to that of Xenopus. Although the genome size of Nanorana is considerably larger than that of Xenopus (2.3 vs. 1.5 Gb), most of the difference is due to the respective number of transposable elements in the two genomes. The two frogs exhibit considerable conserved whole-genome synteny despite having diverged approximately 266 Ma, indicating a slow rate of DNA structural evolution in anurans. Multigenome synteny blocks further show that amphibians have fewer interchromosomal rearrangements than mammals but have a comparable rate of intrachromosomal rearrangements. Our analysis also identifies 11 Mb of anuran-specific highly conserved elements that will be useful for comparative genomic analyses of frogs. The Nanorana genome offers an improved understanding of evolution of tetrapod genomes and also provides a genomic reference for other evolutionary studies.

Fall risk screening protocol for older hearing clinic patients.

Science.gov (United States)

Criter, Robin E; Honaker, Julie A

2017-10-01

The primary purposes of this study were (1) to describe measures that may contrast audiology patients who fall from those who do not fall and (2) to evaluate the clinical performance of measures that could be easily used for fall risk screening in a mainstream audiology hearing clinic. Cross-sectional study Study sample: Thirty-six community-dwelling audiology patient participants and 27 community-dwelling non-audiology patients over 60 years of age. The Hearing Handicap Inventory for the Elderly (HHIE) most accurately identified patients with a recent fall (sensitivity: 76.0%), while the Dizziness Handicap Inventory (DHI) most accurately identified patients without a recent fall (specificity: 90.9%). A combination of measures used in a protocol-including HHIE, DHI, number of medications, and the Timed Up and Go test-resulted in good, accurate identification of patients with or without a recent history of falls (92.0% sensitivity, 100% specificity). This study reports good sensitivity and excellent specificity for identifying patients with and without a recent history of falls when measures were combined into a screening protocol. Despite previously reported barriers, effective fall risk screenings may be performed in hearing clinic settings with measures often readily accessible to audiologists.

Hearing impairment, cognition and speech understanding: exploratory factor analyses of a comprehensive test battery for a group of hearing aid users, the n200 study.

Science.gov (United States)

Rönnberg, Jerker; Lunner, Thomas; Ng, Elaine Hoi Ning; Lidestam, Björn; Zekveld, Adriana Agatha; Sörqvist, Patrik; Lyxell, Björn; Träff, Ulf; Yumba, Wycliffe; Classon, Elisabet; Hällgren, Mathias; Larsby, Birgitta; Signoret, Carine; Pichora-Fuller, M Kathleen; Rudner, Mary; Danielsson, Henrik; Stenfelt, Stefan

2016-11-01

The aims of the current n200 study were to assess the structural relations between three classes of test variables (i.e. HEARING, COGNITION and aided speech-in-noise OUTCOMES) and to describe the theoretical implications of these relations for the Ease of Language Understanding (ELU) model. Participants were 200 hard-of-hearing hearing-aid users, with a mean age of 60.8 years. Forty-three percent were females and the mean hearing threshold in the better ear was 37.4 dB HL. LEVEL1 factor analyses extracted one factor per test and/or cognitive function based on a priori conceptualizations. The more abstract LEVEL 2 factor analyses were performed separately for the three classes of test variables. The HEARING test variables resulted in two LEVEL 2 factors, which we labelled SENSITIVITY and TEMPORAL FINE STRUCTURE; the COGNITIVE variables in one COGNITION factor only, and OUTCOMES in two factors, NO CONTEXT and CONTEXT. COGNITION predicted the NO CONTEXT factor to a stronger extent than the CONTEXT outcome factor. TEMPORAL FINE STRUCTURE and SENSITIVITY were associated with COGNITION and all three contributed significantly and independently to especially the NO CONTEXT outcome scores (R(2) = 0.40). All LEVEL 2 factors are important theoretically as well as for clinical assessment.

The Development and Validation of the Vocalic Sensitivity Test.

Science.gov (United States)

Villaume, William A.; Brown, Mary Helen

1999-01-01

Notes that presbycusis, hearing loss associated with aging, may be marked by a second dimension of hearing loss, a loss in vocalic sensitivity. Reports on the development of the Vocalic Sensitivity Test, which controls for the verbal elements in speech while also allowing for the vocalics to exercise their normal metacommunicative function of…

Tracking occupational hearing loss across global industries: a comparative analysis of metrics.

Science.gov (United States)

Rabinowitz, Peter M; Galusha, Deron; McTague, Michael F; Slade, Martin D; Wesdock, James C; Dixon-Ernst, Christine

2012-01-01

Occupational hearing loss is one of the most prevalent occupational conditions; yet, there is no acknowledged international metric to allow comparisons of risk between different industries and regions. In order to make recommendations for an international standard of occupational hearing loss, members of an international industry group (the International Aluminium Association) submitted details of different hearing loss metrics currently in use by members. We compared the performance of these metrics using an audiometric data set for over 6000 individuals working in 10 locations of one member company. We calculated rates for each metric at each location from 2002 to 2006. For comparison, we calculated the difference of observed-expected (for age) binaural high-frequency hearing loss (in dB/year) for each location over the same time period. We performed linear regression to determine the correlation between each metric and the observed-expected rate of hearing loss. The different metrics produced discrepant results, with annual rates ranging from 0.0% for a less-sensitive metric to more than 10% for a highly sensitive metric. At least two metrics, a 10dB age-corrected threshold shift from baseline and a 15dB nonage-corrected shift metric, correlated well with the difference of observed-expected high-frequency hearing loss. This study suggests that it is feasible to develop an international standard for tracking occupational hearing loss in industrial working populations.

Hearing abilities and sound reception of broadband sounds in an adult Risso's dolphin (Grampus griseus).

Science.gov (United States)

Mooney, T Aran; Yang, Wei-Cheng; Yu, Hsin-Yi; Ketten, Darlene R; Jen, I-Fan

2015-08-01

While odontocetes do not have an external pinna that guides sound to the middle ear, they are considered to receive sound through specialized regions of the head and lower jaw. Yet odontocetes differ in the shape of the lower jaw suggesting that hearing pathways may vary between species, potentially influencing hearing directionality and noise impacts. This work measured the audiogram and received sensitivity of a Risso's dolphin (Grampus griseus) in an effort to comparatively examine how this species receives sound. Jaw hearing thresholds were lowest (most sensitive) at two locations along the anterior, midline region of the lower jaw (the lower jaw tip and anterior part of the throat). Responses were similarly low along a more posterior region of the lower mandible, considered the area of best hearing in bottlenose dolphins. Left- and right-side differences were also noted suggesting possible left-right asymmetries in sound reception or differences in ear sensitivities. The results indicate best hearing pathways may vary between the Risso's dolphin and other odontocetes measured. This animal received sound well, supporting a proposed throat pathway. For Risso's dolphins in particular, good ventral hearing would support their acoustic ecology by facilitating echo-detection from their proposed downward oriented echolocation beam.

On the dynamics of the preference-performance relation for hearing aid noise reduction

DEFF Research Database (Denmark)

Fischer, Rosa-Linde; Wagener, Kirsten C.; Vormann, Matthias

on the data collected during the first laboratory assessment of the study. In particular, the influence of hearing aid experience and individual noise sensitivity on the preference-performance relation will be presented and discussed. REFERENCES S. Getzmann, E. Wascher and M. Falkenstein (2015). "What does......Previous research has shown that hearing aid users can differ substantially in their preference for noise reduction (NR) strength, and that preference for and speech recognition with NR processing typically are not correlated (e.g. Neher 2014; Serman et al. 2016). In other words, hearing aid users...... may prefer a certain NR setting, but perform better with a different one. The aim of the present work was to investigate the influence of individual noise sensitivity, hearing aid experience and acclimatization on the preference-performance relation for different NR settings. For this purpose...

Practical considerations for a second-order directional hearing aid microphone system

Science.gov (United States)

Thompson, Stephen C.

2003-04-01

First-order directional microphone systems for hearing aids have been available for several years. Such a system uses two microphones and has a theoretical maximum free-field directivity index (DI) of 6.0 dB. A second-order microphone system using three microphones could provide a theoretical increase in free-field DI to 9.5 dB. These theoretical maximum DI values assume that the microphones have exactly matched sensitivities at all frequencies of interest. In practice, the individual microphones in the hearing aid always have slightly different sensitivities. For the small microphone separation necessary to fit in a hearing aid, these sensitivity matching errors degrade the directivity from the theoretical values, especially at low frequencies. This paper shows that, for first-order systems the directivity degradation due to sensitivity errors is relatively small. However, for second-order systems with practical microphone sensitivity matching specifications, the directivity degradation below 1 kHz is not tolerable. A hybrid order directive system is proposed that uses first-order processing at low frequencies and second-order directive processing at higher frequencies. This hybrid system is suggested as an alternative that could provide improved directivity index in the frequency regions that are important to speech intelligibility.

Hearing loss

Science.gov (United States)

Decreased hearing; Deafness; Loss of hearing; Conductive hearing loss; Sensorineural hearing loss; Presbycusis ... Symptoms of hearing loss may include: Certain sounds seeming too loud Difficulty following conversations when two or more people are talking ...

About Hearing

Science.gov (United States)

... Info to Go » Hearing-Related » About Hearing About Hearing Each child who is deaf or hard of ... the ear to the brain. Implications: When the hearing mechanism is not functioning Hearing may be impacted ...

Parasympathetic Nervous System Dysfunction, as Identified by Pupil Light Reflex, and Its Possible Connection to Hearing Impairment.

Directory of Open Access Journals (Sweden)

Yang Wang

Full Text Available Although the pupil light reflex has been widely used as a clinical diagnostic tool for autonomic nervous system dysfunction, there is no systematic review available to summarize the evidence that the pupil light reflex is a sensitive method to detect parasympathetic dysfunction. Meanwhile, the relationship between parasympathetic functioning and hearing impairment is relatively unknown.To 1 review the evidence for the pupil light reflex being a sensitive method to evaluate parasympathetic dysfunction, 2 review the evidence relating hearing impairment and parasympathetic activity and 3 seek evidence of possible connections between hearing impairment and the pupil light reflex.Literature searches were performed in five electronic databases. All selected articles were categorized into three sections: pupil light reflex and parasympathetic dysfunction, hearing impairment and parasympathetic activity, pupil light reflex and hearing impairment.Thirty-eight articles were included in this review. Among them, 36 articles addressed the pupil light reflex and parasympathetic dysfunction. We summarized the information in these data according to different types of parasympathetic-related diseases. Most of the studies showed a difference on at least one pupil light reflex parameter between patients and healthy controls. Two articles discussed the relationship between hearing impairment and parasympathetic activity. Both studies reported a reduced parasympathetic activity in the hearing impaired groups. The searches identified no results for pupil light reflex and hearing impairment.As the first systematic review of the evidence, our findings suggest that the pupil light reflex is a sensitive tool to assess the presence of parasympathetic dysfunction. Maximum constriction velocity and relative constriction amplitude appear to be the most sensitive parameters. There are only two studies investigating the relationship between parasympathetic activity and hearing

Parasympathetic Nervous System Dysfunction, as Identified by Pupil Light Reflex, and Its Possible Connection to Hearing Impairment.

Science.gov (United States)

Wang, Yang; Zekveld, Adriana A; Naylor, Graham; Ohlenforst, Barbara; Jansma, Elise P; Lorens, Artur; Lunner, Thomas; Kramer, Sophia E

2016-01-01

Although the pupil light reflex has been widely used as a clinical diagnostic tool for autonomic nervous system dysfunction, there is no systematic review available to summarize the evidence that the pupil light reflex is a sensitive method to detect parasympathetic dysfunction. Meanwhile, the relationship between parasympathetic functioning and hearing impairment is relatively unknown. To 1) review the evidence for the pupil light reflex being a sensitive method to evaluate parasympathetic dysfunction, 2) review the evidence relating hearing impairment and parasympathetic activity and 3) seek evidence of possible connections between hearing impairment and the pupil light reflex. Literature searches were performed in five electronic databases. All selected articles were categorized into three sections: pupil light reflex and parasympathetic dysfunction, hearing impairment and parasympathetic activity, pupil light reflex and hearing impairment. Thirty-eight articles were included in this review. Among them, 36 articles addressed the pupil light reflex and parasympathetic dysfunction. We summarized the information in these data according to different types of parasympathetic-related diseases. Most of the studies showed a difference on at least one pupil light reflex parameter between patients and healthy controls. Two articles discussed the relationship between hearing impairment and parasympathetic activity. Both studies reported a reduced parasympathetic activity in the hearing impaired groups. The searches identified no results for pupil light reflex and hearing impairment. As the first systematic review of the evidence, our findings suggest that the pupil light reflex is a sensitive tool to assess the presence of parasympathetic dysfunction. Maximum constriction velocity and relative constriction amplitude appear to be the most sensitive parameters. There are only two studies investigating the relationship between parasympathetic activity and hearing impairment

How minute sooglossid frogs hear without a middle ear.

Science.gov (United States)

Boistel, Renaud; Aubin, Thierry; Cloetens, Peter; Peyrin, Françoise; Scotti, Thierry; Herzog, Philippe; Gerlach, Justin; Pollet, Nicolas; Aubry, Jean-François

2013-09-17

Acoustic communication is widespread in animals. According to the sensory drive hypothesis [Endler JA (1993) Philos Trans R Soc Lond B Biol Sci 340(1292):215-225], communication signals and perceptual systems have coevolved. A clear illustration of this is the evolution of the tetrapod middle ear, adapted to life on land. Here we report the discovery of a bone conduction-mediated stimulation of the ear by wave propagation in Sechellophryne gardineri, one of the world's smallest terrestrial tetrapods, which lacks a middle ear yet produces acoustic signals. Based on X-ray synchrotron holotomography, we measured the biomechanical properties of the otic tissues and modeled the acoustic propagation. Our models show how bone conduction enhanced by the resonating role of the mouth allows these seemingly deaf frogs to communicate effectively without a middle ear.

Auditory steady-state response thresholds in adults with conductive and mild to moderate sensorineural hearing loss.

Science.gov (United States)

Hosseinabadi, Reza; Jafarzadeh, Sadegh

2015-01-01

The Auditory steady state response (ASSR) provides a frequency-specific and automatic assessment of hearing sensitivity and is used in infants and difficult-to-test adults. The aim of this study was to compare the ASSR thresholds among various types (normal, conductive, and sensorineural), degree (normal, mild, and moderate), and configuration (flat and sloping) of hearing sensitivity, and measuring the cutoff point between normal condition and hearing loss for different frequencies. This clinical trial was performed in Iran and included patients who were referred from Ear, Nose, and Throat Department. A total of 54 adults (27 with sensorineural hearing loss, 17 with conductive hearing losses, and 10 with normal hearing) were randomly chosen to participate in our study. The type and degree of hearing loss were determined through testing by otoscopy, tympanometry, acoustic reflex, and pure tone audiometry. Then the ASSR was tested at carrier frequencies of 500, 1000, 2000, and 4000 Hz. The ASSR accurately estimates the behavioral thresholds as well as flat and sloping configurations. There was no correlation between types of hearing loss and difference of behavioral and ASSR thresholds (P = 0.69). The difference between ASSR and behavioral thresholds decreased as severity of hearing loss increased. The 40, 35, 30, and 35 dB could be considered as cutoffs between normal hearing and hearing loss for 500, 1000, 2000, and 4000 Hz, respectively. The ASSR can accurately predict the degree and configuration of hearing loss and discriminate the normal hearing from mild or moderate hearing loss and mild from moderate hearing loss, except for 500 Hz. The Air-conducted ASSR could not define the type of hearing loss.

Impact of coastal defence structures (tetrapods) on a demersal hard-bottom fish community in the southern North Sea.

Science.gov (United States)

Wehkamp, Stephanie; Fischer, Philipp

2013-02-01

In the coming decades, artificial defence structures will increase in importance worldwide for the protection of coasts against the impacts of global warming. However, the ecological effects of such structures on the natural surroundings remain unclear. We investigated the impact of experimentally introduced tetrapod fields on the demersal fish community in a hard-bottom area in the southern North Sea. The results indicated a significant decrease in fish abundance in the surrounding area caused by migration effects towards the artificial structures. Diversity (HB) and evenness (E) values exhibited greater variation after the introduction of the tetrapods. Additionally, a distinct increase in young-of-the-year (YOY) fish was observed near the structures within the second year after introduction. We suggest that the availability of adequate refuges in combination with additional food resources provided by the artificial structures has a highly species-specific attraction effect. However, these findings also demonstrate that our knowledge regarding the impact of artificial structures on temperate fish communities is still too limited to truly understand the ecological processes that are initiated by the introduction of artificial structures. Long-term investigations and additional experimental in situ work worldwide will be indispensable for a full understanding of the mechanisms by which coastal defence structures interact with the coastal environment. Copyright © 2012 Elsevier Ltd. All rights reserved.

Descriptive Anatomy and Three-Dimensional Reconstruction of the Skull of the Early Tetrapod Acanthostega gunnari Jarvik, 1952

OpenAIRE

Porro, Laura B; Rayfield, Emily J; Clack, Jennifer A.

2015-01-01

The early tetrapod Acanthostega gunnari is an iconic fossil taxon exhibiting skeletal morphology reflecting the transition of vertebrates from water onto land. Computed tomography data of two Acanthostega skulls was segmented using visualization software to digitally separate bone from matrix and individual bones of the skull from each other. A revised description of cranial and lower jaw anatomy in this taxon based on CT data includes new details of sutural morphology, the previously undescr...

Comparison of Various Anthropometric Indices as Risk Factors for Hearing Impairment in Asian Women.

Science.gov (United States)

Kang, Seok Hui; Jung, Da Jung; Lee, Kyu Yup; Choi, Eun Woo; Do, Jun Young

2015-01-01

The objective of the present study was to examine the associations between various anthropometric measures and metabolic syndrome and hearing impairment in Asian women. We identified 11,755 women who underwent voluntary routine health checkups at Yeungnam University Hospital between June 2008 and April 2014. Among these patients, 2,485 participants were <40 years old, and 1,072 participants lacked information regarding their laboratory findings or hearing and were therefore excluded. In total 8,198 participants were recruited into our study. The AUROC value for metabolic syndrome was 0.790 for the waist to hip ratio (WHR). The cutoff value was 0.939. The sensitivity and specificity for predicting metabolic syndrome were 72.7% and 71.7%, respectively. The AUROC value for hearing loss was 0.758 for WHR. The cutoff value was 0.932. The sensitivity and specificity for predicting hearing loss were 65.8% and 73.4%, respectively. The WHR had the highest AUC and was the best predictor of metabolic syndrome and hearing loss. Univariate and multivariate linear regression analyses showed that WHR levels were positively associated with four hearing thresholds including averaged hearing threshold and low, middle, and high frequency thresholds. In addition, multivariate logistic analysis revealed that those with a high WHR had a 1.347-fold increased risk of hearing loss compared with the participants with a low WHR. Our results demonstrated that WHR may be a surrogate marker for predicting the risk of hearing loss resulting from metabolic syndrome.

Tracking occupational hearing loss across global industries: A comparative analysis of metrics

Directory of Open Access Journals (Sweden)

Peter M Rabinowitz

2012-01-01

Full Text Available Occupational hearing loss is one of the most prevalent occupational conditions; yet, there is no acknowledged international metric to allow comparisons of risk between different industries and regions. In order to make recommendations for an international standard of occupational hearing loss, members of an international industry group (the International Aluminium Association submitted details of different hearing loss metrics currently in use by members. We compared the performance of these metrics using an audiometric data set for over 6000 individuals working in 10 locations of one member company. We calculated rates for each metric at each location from 2002 to 2006. For comparison, we calculated the difference of observed-expected (for age binaural high-frequency hearing loss (in dB/year for each location over the same time period. We performed linear regression to determine the correlation between each metric and the observed-expected rate of hearing loss. The different metrics produced discrepant results, with annual rates ranging from 0.0% for a less-sensitive metric to more than 10% for a highly sensitive metric. At least two metrics, a 10dB age-corrected threshold shift from baseline and a 15dB nonage-corrected shift metric, correlated well with the difference of observed-expected high-frequency hearing loss. This study suggests that it is feasible to develop an international standard for tracking occupational hearing loss in industrial working populations.

Hearing impairment, cognition and speech understanding: exploratory factor analyses of a comprehensive test battery for a group of hearing aid users, the n200 study

Science.gov (United States)

Rönnberg, Jerker; Lunner, Thomas; Ng, Elaine Hoi Ning; Lidestam, Björn; Zekveld, Adriana Agatha; Sörqvist, Patrik; Lyxell, Björn; Träff, Ulf; Yumba, Wycliffe; Classon, Elisabet; Hällgren, Mathias; Larsby, Birgitta; Signoret, Carine; Pichora-Fuller, M. Kathleen; Rudner, Mary; Danielsson, Henrik; Stenfelt, Stefan

2016-01-01

Abstract Objective: The aims of the current n200 study were to assess the structural relations between three classes of test variables (i.e. HEARING, COGNITION and aided speech-in-noise OUTCOMES) and to describe the theoretical implications of these relations for the Ease of Language Understanding (ELU) model. Study sample: Participants were 200 hard-of-hearing hearing-aid users, with a mean age of 60.8 years. Forty-three percent were females and the mean hearing threshold in the better ear was 37.4 dB HL. Design: LEVEL1 factor analyses extracted one factor per test and/or cognitive function based on a priori conceptualizations. The more abstract LEVEL 2 factor analyses were performed separately for the three classes of test variables. Results: The HEARING test variables resulted in two LEVEL 2 factors, which we labelled SENSITIVITY and TEMPORAL FINE STRUCTURE; the COGNITIVE variables in one COGNITION factor only, and OUTCOMES in two factors, NO CONTEXT and CONTEXT. COGNITION predicted the NO CONTEXT factor to a stronger extent than the CONTEXT outcome factor. TEMPORAL FINE STRUCTURE and SENSITIVITY were associated with COGNITION and all three contributed significantly and independently to especially the NO CONTEXT outcome scores (R2 = 0.40). Conclusions: All LEVEL 2 factors are important theoretically as well as for clinical assessment. PMID:27589015

Hearing diversity in moths confronting a neotropical bat assemblage.

Science.gov (United States)

Cobo-Cuan, Ariadna; Kössl, Manfred; Mora, Emanuel C

2017-09-01

The tympanal ear is an evolutionary acquisition which helps moths survive predation from bats. The greater diversity of bats and echolocation strategies in the Neotropics compared with temperate zones would be expected to impose different sensory requirements on the neotropical moths. However, even given some variability among moth assemblages, the frequencies of best hearing of moths from different climate zones studied to date have been roughly the same: between 20 and 60 kHz. We have analyzed the auditory characteristics of tympanate moths from Cuba, a neotropical island with high levels of bat diversity and a high incidence of echolocation frequencies above those commonly at the upper limit of moths' hearing sensitivity. Moths of the superfamilies Noctuoidea, Geometroidea and Pyraloidea were examined. Audiograms were determined by non-invasively measuring distortion-product otoacoustic emissions. We also quantified the frequency spectrum of the echolocation sounds to which this moth community is exposed. The hearing ranges of moths in our study showed best frequencies between 36 and 94 kHz. High sensitivity to frequencies above 50 kHz suggests that the auditory sensitivity of moths is suited to the sounds used by sympatric echolocating bat fauna. Biodiversity characterizes predators and prey in the Neotropics, but the bat-moth acoustic interaction keeps spectrally matched.

Introduction to audiology: Some basics about hearing loss, hearing technologies and barriers to hearing aid use

DEFF Research Database (Denmark)

Mourtou, Eleni; Meis, Markus

2012-01-01

This chapter provides background information for researchers who wish to become familiar with some basic medical and audiological aspects of hearing loss and the technology of hearing aids. It introduces (1) the disciplines involved in research on hearing loss, (2) the medical categories of hearing...... loss and their various effects on communication, (3) the different degrees of hearing loss as defined by different national and international organizations, (4) statistics on the preva- lence of hearing loss worldwide, (5) some technological aspects of hearing instruments, (6) sta- tistics on non...

Negotiating hearing disability and hearing disabled identities

DEFF Research Database (Denmark)

Lykke Hindhede, Anette

2012-01-01

  　 Using disability theory as a framework and social science theories of identity to strengthen the arguments, this paper explores empirically how working-age adults confront the medical diagnosis of hearing impairment. For most participants hearing impairment threatens the stability of social...... interaction and the construction of hearing disabled identities is seen as shaped in the interaction with the hearing impaired person‟s surroundings. In order to overcome the potential stigmatisation the „passing‟ as normal becomes predominant. For many the diagnosis provokes radical redefinitions of the self....... The discursively produced categorisation and subjectivity of senescence mean that rehabilitation technologies such as hearing aids identify a particular life-style (disabled) which determines their social significance. Thus wearing a hearing aid works against the contemporary attempt to create socially ideal...

Effects of Hearing Loss and Fast-Acting Compression on Amplitude Modulation Perception and Speech Intelligibility

DEFF Research Database (Denmark)

Wiinberg, Alan; Jepsen, Morten Løve; Epp, Bastian

2018-01-01

Objective: The purpose was to investigate the effects of hearing-loss and fast-acting compression on speech intelligibility and two measures of temporal modulation sensitivity. Design: Twelve adults with normal hearing (NH) and 16 adults with mild to moderately severe sensorineural hearing loss......, the MDD thresholds were higher for the group with hearing loss than for the group with NH. Fast-acting compression increased the modulation detection thresholds, while no effect of compression on the MDD thresholds was observed. The speech reception thresholds obtained in stationary noise were slightly...... of the modulation detection thresholds, compression does not seem to provide a benefit for speech intelligibility. Furthermore, fast-acting compression may not be able to restore MDD thresholds to the values observed for listeners with NH, suggesting that the two measures of amplitude modulation sensitivity...

Hearing aid processing strategies for listeners with different auditory profiles: Insights from the BEAR project

DEFF Research Database (Denmark)

Wu, Mengfan; El-Haj-Ali, Mouhamad; Sanchez Lopez, Raul

hearing aid settings that differed in terms of signal-to-noise ratio (SNR) improvement and temporal and spectral speech distortions were selected for testing based on a comprehensive technical evaluation of different parameterisations of the hearing aid simulator. Speech-in-noise perception was assessed...... stimulus comparison paradigm. RESULTS We hypothesize that the perceptual outcomes from the six hearing aid settings will differ across listeners with different auditory profiles. More specifically, we expect listeners showing high sensitivity to temporal and spectral differences to perform best with and....../or to favour hearing aid settings that preserve those cues. In contrast, we expect listeners showing low sensitivity to temporal and spectral differences to perform best with and/or to favour settings that maximize SNR improvement, independent of any additional speech distortions. Altogether, we anticipate...

Age-related hearing loss in sea lions and their scientists

Science.gov (United States)

Schusterman, Ronald J.; Southall, Brandon; Kastak, David; Reichmuth Kastak, Colleen

2002-05-01

Interest in the hearing capabilities of California sea lions (Zalophus californianus) was first stimulated by the echolocation hypothesis and more recently by rising concern about coastal noise pollution. During a series of audiometric tests, we measured the absolute hearing sensitivity of two sea lions and two of their human investigators. Aerial hearing curves for each subject were obtained with a go/no-go procedure and standard psychophysics. Additionally, underwater hearing curves were obtained for the sea lions using the same procedures. Underwater, the older sea lion (22-25 years of age) showed hearing losses relative to the younger sea lion (13-16 years) that ranged from 10 dB at lower frequencies to 50 dB near the upper frequency limit. The older sea lions' hearing losses in air were consistent with those measured underwater. The older human (69 years) tested also showed losses relative to the younger human (22 years). These differences ranged from 15 dB at lower frequencies up to 35 dB at the highest frequency tested. The results obtained in this study document age-related hearing losses in sea lions and humans. The findings are consistent with data on presbycusis in other mammalian species, showing that maximum hearing loss occurs at the highest frequencies.

Assessment of hearing and hearing disorders in rock/jazz musicians.

Science.gov (United States)

Kähärit, Kim; Zachau, Gunilla; Eklöf, Mats; Sandsjö, Leif; Möller, Claes

2003-07-01

The aim of this study was to assess hearing and hearing disorders among rock/jazz musicians. One hundred and thirty-nine (43 women and 96 men) musicians participated. The results are based on pure-tone audiometry and questionnaire responses. According to our definition of hearing loss, tinnitus, hyperacusis, distortion and/or diplacusis as hearing disorders, we found disorders in 74%, of the rock/jazz musicians studied. Hearing loss, tinnitus and hyperacusis were most common, and the latter two were found significantly more frequently than in different reference populations. The women showed bilateral, significantly better hearing thresholds at 3-6 kHz than the men. Hyperacusis, and the combination of both hyperacusis and tinnitus, were found to be significantly more frequent among women than among men. Hearing loss and tinnitus were significantly more common among men than among women. It is important to evaluate all kinds of hearing problems (other than hearing loss) in musicians, since they represent an occupational group especially dependent on optimal, functional hearing. On the basis of our results, we suggest that hearing problems such as tinnitus, hyperacusis, distortion and/or diplacusis should, in addition to hearing loss, be defined as hearing disorders.

Can You Hear Architecture

DEFF Research Database (Denmark)

Ryhl, Camilla

2016-01-01

Taking an off set in the understanding of architectural quality being based on multisensory architecture, the paper aims to discuss the current acoustic discourse in inclusive design and its implications to the integration of inclusive design in architectural discourse and practice as well...... as the understanding of user needs. The paper further points to the need to elaborate and nuance the discourse much more, in order to assure inclusion to the many users living with a hearing impairment or, for other reasons, with a high degree of auditory sensitivity. Using the authors’ own research on inclusive...... design and architectural quality for people with a hearing disability and a newly conducted qualitative evaluation research in Denmark as well as architectural theories on multisensory aspects of architectural experiences, the paper uses examples of existing Nordic building cases to discuss the role...

Validation of questionnaire-reported hearing with medical records: A report from the Swiss Childhood Cancer Survivor Study.

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Annette Weiss

Full Text Available Hearing loss is a potential late effect after childhood cancer. Questionnaires are often used to assess hearing in large cohorts of childhood cancer survivors and it is important to know if they can provide valid measures of hearing loss. We therefore assessed agreement and validity of questionnaire-reported hearing in childhood cancer survivors using medical records as reference.In this validation study, we studied 361 survivors of childhood cancer from the Swiss Childhood Cancer Survivor Study (SCCSS who had been diagnosed after 1989 and had been exposed to ototoxic cancer treatment. Questionnaire-reported hearing was compared to the information in medical records. Hearing loss was defined as ≥ grade 1 according to the SIOP Boston Ototoxicity Scale. We assessed agreement and validity of questionnaire-reported hearing overall and stratified by questionnaire respondents (survivor or parent, sociodemographic characteristics, time between follow-up and questionnaire and severity of hearing loss.Questionnaire reports agreed with medical records in 85% of respondents (kappa 0.62, normal hearing was correctly assessed in 92% of those with normal hearing (n = 249, and hearing loss was correctly assessed in 69% of those with hearing loss (n = 112. Sensitivity of the questionnaires was 92%, 74%, and 39% for assessment of severe, moderate and mild bilateral hearing loss; and 50%, 33% and 10% for severe, moderate and mild unilateral hearing loss, respectively. Results did not differ by sociodemographic characteristics of the respondents, and survivor- and parent-reports were equally valid.Questionnaires are a useful tool to assess hearing in large cohorts of childhood cancer survivors, but underestimate mild and unilateral hearing loss. Further research should investigate whether the addition of questions with higher sensitivity for mild degrees of hearing loss could improve the results.

Validation of questionnaire-reported hearing with medical records: A report from the Swiss Childhood Cancer Survivor Study

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Scheinemann, Katrin; Grotzer, Michael; Kompis, Martin; Kuehni, Claudia E.

2017-01-01

Background Hearing loss is a potential late effect after childhood cancer. Questionnaires are often used to assess hearing in large cohorts of childhood cancer survivors and it is important to know if they can provide valid measures of hearing loss. We therefore assessed agreement and validity of questionnaire-reported hearing in childhood cancer survivors using medical records as reference. Procedure In this validation study, we studied 361 survivors of childhood cancer from the Swiss Childhood Cancer Survivor Study (SCCSS) who had been diagnosed after 1989 and had been exposed to ototoxic cancer treatment. Questionnaire-reported hearing was compared to the information in medical records. Hearing loss was defined as ≥ grade 1 according to the SIOP Boston Ototoxicity Scale. We assessed agreement and validity of questionnaire-reported hearing overall and stratified by questionnaire respondents (survivor or parent), sociodemographic characteristics, time between follow-up and questionnaire and severity of hearing loss. Results Questionnaire reports agreed with medical records in 85% of respondents (kappa 0.62), normal hearing was correctly assessed in 92% of those with normal hearing (n = 249), and hearing loss was correctly assessed in 69% of those with hearing loss (n = 112). Sensitivity of the questionnaires was 92%, 74%, and 39% for assessment of severe, moderate and mild bilateral hearing loss; and 50%, 33% and 10% for severe, moderate and mild unilateral hearing loss, respectively. Results did not differ by sociodemographic characteristics of the respondents, and survivor- and parent-reports were equally valid. Conclusions Questionnaires are a useful tool to assess hearing in large cohorts of childhood cancer survivors, but underestimate mild and unilateral hearing loss. Further research should investigate whether the addition of questions with higher sensitivity for mild degrees of hearing loss could improve the results. PMID:28333999

Double Jeopardy: Hearing Loss and Tinnitus Among Noise-Exposed Workers.

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Hong, OiSaeng; Chin, Dal Lae; Phelps, Stephanie; Joo, Yoonmee

2016-06-01

The purpose of this study was to determine the prevalence and characteristics of tinnitus and assess the relationship between tinnitus and hearing loss among firefighters and operating engineers, who are exposed to noise on-the-job. The study analyzed existing data from two different populations (154 firefighters and 769 operating engineers) who completed a survey and audiometric tests as part of a hearing loss prevention intervention study. Approximately 40% of both groups reported tinnitus; 34% of firefighters and 59% of operating engineers showed hearing loss at noise-sensitive frequencies (4 kHz and 6 kHz). Firefighters with high frequency hearing loss (odds ratio [OR] = 2.31; 95% confidence interval [CI] = [1.05, 5.11]) and those with perceived impaired hearing status (OR = 3.53; 95% CI = [1.27, 9.80]) were significantly more likely to report tinnitus. Similarly, operating engineers who had hearing loss at both low (OR = 2.10; 95% CI = [1.40, 3.15]) and high frequencies (OR = 2.00; 95% CI = [1.37, 2.90]), and perceived impaired hearing status (OR = 2.17; 95% CI = [1.55, 3.05]) were twice as likely to report tinnitus. This study demonstrated that tinnitus is a considerable problem for noise-exposed workers. Workers with hearing loss demonstrated significantly higher rates of tinnitus. Comprehensive workplace hearing conservation programs should include tinnitus management for noise-exposed workers, along with other key elements such as noise control and hearing protection. © 2016 The Author(s).

Motivational engagement in first-time hearing aid users: A feasibility study.

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Ferguson, Melanie; Maidment, David; Russell, Naomi; Gregory, Melanie; Nicholson, Richard

2016-07-01

To assess (1) the feasibility of incorporating the Ida Institute's Motivation Tools into a UK audiology service, (2) the potential benefits of motivational engagement in first-time hearing aid users, and (3) predictors of hearing aid and general health outcome measures. A feasibility study using a single-centre, prospective, quasi-randomized controlled design with two arms. The Ida Institute's Motivation Tools formed the basis for motivational engagement. First-time hearing aid users were recruited at the initial hearing assessment appointment. The intervention arm underwent motivational engagement (M+, n = 32), and a control arm (M-, n = 36) received standard care only. The M+ group showed greater self-efficacy, reduced anxiety, and greater engagement with the audiologist at assessment and fitting appointments. However, there were no significant between-group differences 10-weeks post-fitting. Hearing-related communication scores predicted anxiety, and social isolation scores predicted depression for the M+ group. Readiness to address hearing difficulties predicted hearing aid outcomes for the M- group. Hearing sensitivity was not a predictor of outcomes. There were some positive results from motivational engagement early in the patient journey. Future research should consider using qualitative methods to explore whether there are longer-term benefits of motivational engagement in hearing aid users.

Comparing Analog and Digital Hearing Aids in Reducing Hearing Disability

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Ghassem Mohammad Khani

2004-06-01

Full Text Available Objective: Comparing analog and digital hearing aids reducing disability caused by hearing deficiency among moderate to severe sensorineural hearing-impaired persons. Method and Material: This descriptive-analytic study was carried out on two groups of subjects participated in this study in some audiology clinics of hearing aid since May 2002 to October 2003. Twenty subjects wore analog hearing aids and twenty one subjects wore digital hearing aids. In this study , no subject had previous middle ear or psychological problems. APHAB questionnaire was completed before using hearing aid and 2 months after to determine benefit of hearing aid use. Results: Total score mean of APHAB inventory before and after use of analoge hearing aids were 52.215+6.420 and 32.300+3.443 respectively. Also total score mean of APHAB inventory before and after use of digital hearing aids were 54.9252+9.028 and 26.321+10.916 respectively. There was no significant difference between total mean score of APHAB inventory before and after using analog and digital hearing aids (P=0.058.While there was significant difference between total mean score of APHAB questionnaire before and after use of analog hearing aids (P<0.001 and also before and after use of digital hearing aids (P<0.001. Moreover age, gender , litracy level , occupation , degree of hearing loss and manner of hearing aid usage did not have significant effect on APHAB results. Configuration of loss had siginficant effect on aversiveness subscale before and after use of analog hearing aids (P=0.008. Previous experience and duration of hearing aid usage had significant effect on aversiveness subscale before and after use of digital hearing aids (P=0.043 and (P=0.024, respectively , while all of these three items did not have significant effect on total mean score of APHAB inventory and also total mean scores of three subscales of ease of communication , reverberation and background noise. Conclusion: Comparing to

Hearing: Noise-Induced Hearing Loss

Science.gov (United States)

... reduce your exposure to noise by choosing quiet leisure activities rather than noisy ones. Develop the habit ... the degree of your hearing loss, you may benefit from using a hearing aid (a device you ...

Cross-sectional evaluation of an internet-based hearing screening test in an occupational setting

NARCIS (Netherlands)

Sheikh Rashid, Marya; Leensen, Monique Cj; de Laat, Jan Apm; Dreschler, Wouter A.

2017-01-01

Objectives The Occupational Earcheck (OEC) is an online internet test to detect high-frequency hearing loss for the purposes of occupational hearing screening. In this study, we evaluated the OEC in an occupational setting in order to assess test sensitivity, specificity, and validity. Methods A

Prevalence of hearing loss and accuracy of self-report among factory workers.

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McCullagh, Marjorie C; Raymond, Delbert; Kerr, Madeleine J; Lusk, Sally L

2011-01-01

Noise represents one of the most common occupational health hazards. A Healthy People 2020 objective aims to reduce hearing loss in the noise-exposed public. The purpose of this study was to describe and compare perceived and measured hearing, and to determine the prevalence of hearing loss among a group of factory workers. Data collected as part of an intervention study promoting hearing protector use among workers at an automotive factory in the Midwest were used. Plant employees (n=2691) provided information regarding their perceived hearing ability, work role, and other demographics. The relationships among audiograms, a single-item measure of perceived hearing ability, and demographic data were explored using chi-square, McNemar's test, Mann-Whitney U-test, sensitivity, and specificity. The prevalence of hearing loss among noise-exposed factory workers was 42% (where hearing loss was defined as >25 dB loss at the OSHA-recommended frequencies of 2, 3, and 4 kHz in either ear). However, 76% of workers reported their hearing ability as excellent or good. The difference in perceived hearing ability was significant at each tested frequency between those with and without measured hearing loss. Self-reported hearing ability was poorly related to results of audiometry. Although this group of workers was employed in a regulated environment and served by a hearing conservation program, hearing loss was highly prevalent. These findings, together with national prevalence estimates, support the need for evaluation of hearing conservation programs and increased attention to the national goal of reducing adult hearing loss.

Prevalence of hearing loss and accuracy of self-report among factory workers

Directory of Open Access Journals (Sweden)

Marjorie C McCullagh

2011-01-01

Full Text Available Noise represents one of the most common occupational health hazards. A Healthy People 2020 objective aims to reduce hearing loss in the noise-exposed public. The purpose of this study was to describe and compare perceived and measured hearing, and to determine the prevalence of hearing loss among a group of factory workers. Data collected as part of an intervention study promoting hearing protector use among workers at an automotive factory in the Midwest were used. Plant employees (n=2691 provided information regarding their perceived hearing ability, work role, and other demographics. The relationships among audiograms, a single-item measure of perceived hearing ability, and demographic data were explored using chi-square, McNemar′s test, Mann-Whitney U-test, sensitivity, and specificity. The prevalence of hearing loss among noise-exposed factory workers was 42% (where hearing loss was defined as >25 dB loss at the OSHA-recommended frequencies of 2, 3, and 4 kHz in either ear. However, 76% of workers reported their hearing ability as excellent or good. The difference in perceived hearing ability was significant at each tested frequency between those with and without measured hearing loss. Self-reported hearing ability was poorly related to results of audiometry. Although this group of workers was employed in a regulated environment and served by a hearing conservation program, hearing loss was highly prevalent. These findings, together with national prevalence estimates, support the need for evaluation of hearing conservation programs and increased attention to the national goal of reducing adult hearing loss.

Hearing Screening

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Johnson-Curiskis, Nanette

2012-01-01

Hearing levels are threatened by modern life--headsets for music, rock concerts, traffic noises, etc. It is crucial we know our hearing levels so that we can draw attention to potential problems. This exercise requires that students receive a hearing screening for their benefit as well as for making the connection of hearing to listening.

45 CFR 81.51 - Notice of hearing or opportunity for hearing.

Science.gov (United States)

2010-10-01

... 45 Public Welfare 1 2010-10-01 2010-10-01 false Notice of hearing or opportunity for hearing. 81.51 Section 81.51 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION PRACTICE AND PROCEDURE FOR HEARINGS UNDER PART 80 OF THIS TITLE Proceedings Prior to Hearing § 81.51 Notice of hearing or opportunity for hearing....

Evaluating auditory perception and communication demands required to carry out work tasks and complimentary hearing resources and skills for older workers with hearing loss.

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Jennings, M B; Shaw, L; Hodgins, H; Kuchar, D A; Bataghva, L Poost-Foroosh

2010-01-01

For older workers with acquired hearing loss, this loss as well as the changing nature of work and the workforce, may lead to difficulties and disadvantages in obtaining and maintaining employment. Currently there are very few instruments that can assist workplaces, employers and workers to prepare for older workers with hearing loss or with the evaluation of auditory perception demands of work, especially those relevant to communication, and safety sensitive workplaces that require high levels of communication. This paper introduces key theoretical considerations that informed the development of a new framework, The Audiologic Ergonomic (AE) Framework to guide audiologists, work rehabilitation professionals and workers in developing tools to support the identification and evaluation of auditory perception demands in the workplace, the challenges to communication and the subsequent productivity and safety in the performance of work duties by older workers with hearing loss. The theoretical concepts underpinning this framework are discussed along with next steps in developing tools such as the Canadian Hearing Demands Tool (C-HearD Tool) in advancing approaches to evaluate auditory perception and communication demands in the workplace.

High-frequency Audiometry Hearing on Monitoring of Individuals Exposed to Occupational Noise: A Systematic Review.

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Antonioli, Cleonice Aparecida Silva; Momensohn-Santos, Teresa Maria; Benaglia, Tatiana Aparecida Silva

2016-07-01

The literature reports on high-frequency audiometry as one of the exams used on hearing monitoring of individuals exposed to high sound pressure in their work environment, due to the method́s greater sensitivity in early identification of hearing loss caused by noise. The frequencies that compose the exam are generally between 9 KHz and 20KHz, depending on the equipment. This study aims to perform a retrospective and secondary systematic revision of publications on high-frequency audiometry on hearing monitoring of individuals exposed to occupational noise. This systematic revision followed the methodology proposed in the Cochrane Handbook, focusing on the question: "Is High-frequency Audiometry more sensitive than Conventional Audiometry in the screening of early hearing loss individuals exposed to occupational noise?" The search was based on PubMed data, Base, Web of Science (Capes), Biblioteca Virtual em Saúde (BVS), and in the references cited in identified and selected articles. The search resulted in 6059 articles in total. Of these, only six studies were compatible with the criteria proposed in this study. The performed meta-analysis does not definitively answer the study's proposed question. It indicates that the 16 KHz high frequency audiometry (HFA) frequency is sensitive in early identification of hearing loss in the control group (medium difference (MD = 8.33)), as well as the 4 KHz frequency (CA), this one being a little less expressive (MD = 5.72). Thus, others studies are necessary to confirm the HFA importance for the early screening of hearing loss on individuals exposed to noise at the workplace.

Diagnosis of hearing loss using automated audiometry in an asynchronous telehealth model: A pilot accuracy study.

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Brennan-Jones, Christopher G; Eikelboom, Robert H; Swanepoel, De Wet

2017-02-01

Introduction Standard criteria exist for diagnosing different types of hearing loss, yet audiologists interpret audiograms manually. This pilot study examined the feasibility of standardised interpretations of audiometry in a telehealth model of care. The aim of this study was to examine diagnostic accuracy of automated audiometry in adults with hearing loss in an asynchronous telehealth model using pre-defined diagnostic protocols. Materials and methods We recruited 42 study participants from a public audiology and otolaryngology clinic in Perth, Western Australia. Manual audiometry was performed by an audiologist either before or after automated audiometry. Diagnostic protocols were applied asynchronously for normal hearing, disabling hearing loss, conductive hearing loss and unilateral hearing loss. Sensitivity and specificity analyses were conducted using a two-by-two matrix and Cohen's kappa was used to measure agreement. Results The overall sensitivity for the diagnostic criteria was 0.88 (range: 0.86-1) and overall specificity was 0.93 (range: 0.86-0.97). Overall kappa ( k) agreement was 'substantial' k = 0.80 (95% confidence interval (CI) 0.70-0.89) and significant at p loss. This method has the potential to improve synchronous and asynchronous tele-audiology service delivery.

Pure tone audiograms and possible aminoglycoside-induced hearing loss in belugas (Delphinapterus leucas)

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Finneran, James J.; Carder, Donald A.; Dear, Randall; Belting, Traci; McBain, Jim; Dalton, Les; Ridgway, Sam H.

2005-06-01

A behavioral response paradigm was used to measure pure-tone hearing sensitivities in two belugas (Delphinapterus leucas). Tests were conducted over a 20-month period at the Point Defiance Zoo and Aquarium, in Tacoma, WA. Subjects were two males, aged 8-10 and 9-11 during the course of the study. Subjects were born in an oceanarium and had been housed together for all of their lives. Hearing thresholds were measured using a modified up/down staircase procedure and acoustic response paradigm where subjects were trained to produce audible responses to test tones and to remain quiet otherwise. Test frequencies ranged from approximately 2 to 130 kHz. Best sensitivities ranged from approximately 40 to 50 dB re 1 μPa at 50-80 kHz and 30-35 kHz for the two subjects. Although both subjects possessed traditional ``U-shaped'' mammalian audiograms, one subject exhibited significant high-frequency hearing loss above 37 kHz compared to previously published data for belugas. Hearing loss in this subject was estimated to approach 90 dB for frequencies above 50 kHz. Similar ages, ancestry, and environmental conditions between subjects, but a history of ototoxic drug administration in only one subject, suggest that the observed hearing loss was a result of the aminoglycoside antibiotic amikacin. .

Assessment of hearing threshold in adults with hearing loss using an automated system of cortical auditory evoked potential detection

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Alessandra Spada Durante

Full Text Available Abstract Introduction: The use of hearing aids by individuals with hearing loss brings a better quality of life. Access to and benefit from these devices may be compromised in patients who present difficulties or limitations in traditional behavioral audiological evaluation, such as newborns and small children, individuals with auditory neuropathy spectrum, autism, and intellectual deficits, and in adults and the elderly with dementia. These populations (or individuals are unable to undergo a behavioral assessment, and generate a growing demand for objective methods to assess hearing. Cortical auditory evoked potentials have been used for decades to estimate hearing thresholds. Current technological advances have lead to the development of equipment that allows their clinical use, with features that enable greater accuracy, sensitivity, and specificity, and the possibility of automated detection, analysis, and recording of cortical responses. Objective: To determine and correlate behavioral auditory thresholds with cortical auditory thresholds obtained from an automated response analysis technique. Methods: The study included 52 adults, divided into two groups: 21 adults with moderate to severe hearing loss (study group; and 31 adults with normal hearing (control group. An automated system of detection, analysis, and recording of cortical responses (HEARLab® was used to record the behavioral and cortical thresholds. The subjects remained awake in an acoustically treated environment. Altogether, 150 tone bursts at 500, 1000, 2000, and 4000 Hz were presented through insert earphones in descending-ascending intensity. The lowest level at which the subject detected the sound stimulus was defined as the behavioral (hearing threshold (BT. The lowest level at which a cortical response was observed was defined as the cortical electrophysiological threshold. These two responses were correlated using linear regression. Results: The cortical

Assessment of hearing threshold in adults with hearing loss using an automated system of cortical auditory evoked potential detection.

Science.gov (United States)

Durante, Alessandra Spada; Wieselberg, Margarita Bernal; Roque, Nayara; Carvalho, Sheila; Pucci, Beatriz; Gudayol, Nicolly; de Almeida, Kátia

The use of hearing aids by individuals with hearing loss brings a better quality of life. Access to and benefit from these devices may be compromised in patients who present difficulties or limitations in traditional behavioral audiological evaluation, such as newborns and small children, individuals with auditory neuropathy spectrum, autism, and intellectual deficits, and in adults and the elderly with dementia. These populations (or individuals) are unable to undergo a behavioral assessment, and generate a growing demand for objective methods to assess hearing. Cortical auditory evoked potentials have been used for decades to estimate hearing thresholds. Current technological advances have lead to the development of equipment that allows their clinical use, with features that enable greater accuracy, sensitivity, and specificity, and the possibility of automated detection, analysis, and recording of cortical responses. To determine and correlate behavioral auditory thresholds with cortical auditory thresholds obtained from an automated response analysis technique. The study included 52 adults, divided into two groups: 21 adults with moderate to severe hearing loss (study group); and 31 adults with normal hearing (control group). An automated system of detection, analysis, and recording of cortical responses (HEARLab ® ) was used to record the behavioral and cortical thresholds. The subjects remained awake in an acoustically treated environment. Altogether, 150 tone bursts at 500, 1000, 2000, and 4000Hz were presented through insert earphones in descending-ascending intensity. The lowest level at which the subject detected the sound stimulus was defined as the behavioral (hearing) threshold (BT). The lowest level at which a cortical response was observed was defined as the cortical electrophysiological threshold. These two responses were correlated using linear regression. The cortical electrophysiological threshold was, on average, 7.8dB higher than the

Auditory analysis of xeroderma pigmentosum 1971-2012: hearing function, sun sensitivity and DNA repair predict neurological degeneration.

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Totonchy, Mariam B; Tamura, Deborah; Pantell, Matthew S; Zalewski, Christopher; Bradford, Porcia T; Merchant, Saumil N; Nadol, Joseph; Khan, Sikandar G; Schiffmann, Raphael; Pierson, Tyler Mark; Wiggs, Edythe; Griffith, Andrew J; DiGiovanna, John J; Kraemer, Kenneth H; Brewer, Carmen C

2013-01-01

To assess the role of DNA repair in maintenance of hearing function and neurological integrity, we examined hearing status, neurological function, DNA repair complementation group and history of acute burning on minimal sun exposure in all patients with xeroderma pigmentosum, who had at least one complete audiogram, examined at the National Institutes of Health from 1971 to 2012. Seventy-nine patients, aged 1-61 years, were diagnosed with xeroderma pigmentosum (n = 77) or xeroderma pigmentosum/Cockayne syndrome (n = 2). A total of 178 audiograms were included. Clinically significant hearing loss (>20 dB) was present in 23 (29%) of 79 patients. Of the 17 patients with xeroderma pigmentosum-type neurological degeneration, 13 (76%) developed hearing loss, and all 17 were in complementation groups xeroderma pigmentosum type A or type D and reported acute burning on minimal sun exposure. Acute burning on minimal sun exposure without xeroderma pigmentosum-type neurological degeneration was present in 18% of the patients (10/55). Temporal bone histology in a patient with severe xeroderma pigmentosum-type neurological degeneration revealed marked atrophy of the cochlear sensory epithelium and neurons. The 19-year mean age of detection of clinically significant hearing loss in the patients with xeroderma pigmentosum with xeroderma pigmentosum-type neurological degeneration was 54 years younger than that predicted by international norms. The four frequency (0.5/1/2/4 kHz) pure-tone average correlated with degree of neurodegeneration (P xeroderma pigmentosum, aged 4-30 years, a four-frequency pure-tone average ≥10 dB hearing loss was associated with a 39-fold increased risk (P = 0.002) of having xeroderma pigmentosum-type neurological degeneration. Severity of hearing loss parallels neurological decline in patients with xeroderma pigmentosum-type neurological degeneration. Audiometric findings, complementation group, acute burning on minimal sun exposure and age were

Development of a test of suprathreshold acuity in noise in Brazilian Portuguese: a new method for hearing screening and surveillance.

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Vaez, Nara; Desgualdo-Pereira, Liliane; Paglialonga, Alessia

2014-01-01

This paper describes the development of a speech-in-noise test for hearing screening and surveillance in Brazilian Portuguese based on the evaluation of suprathreshold acuity performances. The SUN test (Speech Understanding in Noise) consists of a list of intervocalic consonants in noise presented in a multiple-choice paradigm by means of a touch screen. The test provides one out of three possible results: "a hearing check is recommended" (red light), "a hearing check would be advisable" (yellow light), and "no hearing difficulties" (green light) (Paglialonga et al., Comput. Biol. Med. 2014). This novel test was developed in a population of 30 normal hearing young adults and 101 adults with varying degrees of hearing impairment and handicap, including normal hearing. The test had 84% sensitivity and 76% specificity compared to conventional pure-tone screening and 83% sensitivity and 86% specificity to detect disabling hearing impairment. The test outcomes were in line with the degree of self-perceived hearing handicap. The results found here paralleled those reported in the literature for the SUN test and for conventional speech-in-noise measures. This study showed that the proposed test might be a viable method to identify individuals with hearing problems to be referred to further audiological assessment and intervention.

Development of a Test of Suprathreshold Acuity in Noise in Brazilian Portuguese: A New Method for Hearing Screening and Surveillance

Directory of Open Access Journals (Sweden)

Nara Vaez

2014-01-01

Full Text Available This paper describes the development of a speech-in-noise test for hearing screening and surveillance in Brazilian Portuguese based on the evaluation of suprathreshold acuity performances. The SUN test (Speech Understanding in Noise consists of a list of intervocalic consonants in noise presented in a multiple-choice paradigm by means of a touch screen. The test provides one out of three possible results: “a hearing check is recommended” (red light, “a hearing check would be advisable” (yellow light, and “no hearing difficulties” (green light (Paglialonga et al., Comput. Biol. Med. 2014. This novel test was developed in a population of 30 normal hearing young adults and 101 adults with varying degrees of hearing impairment and handicap, including normal hearing. The test had 84% sensitivity and 76% specificity compared to conventional pure-tone screening and 83% sensitivity and 86% specificity to detect disabling hearing impairment. The test outcomes were in line with the degree of self-perceived hearing handicap. The results found here paralleled those reported in the literature for the SUN test and for conventional speech-in-noise measures. This study showed that the proposed test might be a viable method to identify individuals with hearing problems to be referred to further audiological assessment and intervention.

Perception of a Sung Vowel as a Function of Frequency-Modulation Rate and Excursionin Normal-Hearing and Hearing-Impaired Listeners

DEFF Research Database (Denmark)

Vatti, Marianna; Santurette, Sébastien; Pontoppidan, Niels henrik

2014-01-01

Purpose: Frequency fluctuations in human voices can usually be described as coherent frequency modulation (FM). As listeners with hearing impairment (HI listeners) are typically less sensitive to FM than listeners with normal hearing (NH listeners), this study investigated whether hearing loss...... affects the perception of a sung vowel based on FM cues. Method: Vibrato maps were obtained in 14 NH and 12 HI listeners with different degrees of musical experience. The FM rate and FM excursion of a synthesized vowel, to which coherent FM was applied, were adjusted until a singing voice emerged. Results......: In NH listeners, adding FM to the steady vowel components produced perception of a singing voice for FM rates between 4.1 and 7.5 Hz and FM excursions between 17 and 83 cents on average. In contrast, HI listeners showed substantially broader vibrato maps. Individual differences in map boundaries were...

Hearing thresholds and ventilation tube treatment in children with unilateral cleft lip and palate.

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Tengroth, Birgitta; Hederstierna, Christina; Neovius, Erik; Flynn, Traci

2017-06-01

Children with cleft lip and palate have a high prevalence of otitis media with effusion (OME) which is often associated with a fluctuating, conductive hearing loss in the low and mid-frequencies and a risk for permanent hearing loss in the higher frequencies. Although common, there is no consensus on the treatment of OME with ventilation tubes. The aim of this study is to document if the risk for permanent hearing loss and acquired cholesteatoma increases due to treatment with ventilation tubes (VT treatments) during childhood in a group of children with cleft lip and palate. A retrospective medical chart review of 33 children (25 boys and 8 girls) born with unilateral cleft lip and palate (UCLP) was completed. Audiological data (results of hearing sensitivity tests, the total number of hearing tests, and number of VT treatments) were extracted from medical records from when the children were 4-7 and >7-10 years of age. The hearing thresholds in the speech frequencies improved with age (p 7-10 years of age. There were no significant correlations between number of VT treatments and hearing thresholds at >7-10 years. Four of the 33 children presented with complications: two children exhibited perforations of the ear drum (6.1%) and two children developed unilateral cholesteatoma (6.1%). In the current study, the hearing sensitivity of children with cleft lip and palate improved with age. However, this improvement was not seen in the higher frequencies. Twelve percent of the children experienced complications following VT treatments. Due to these complications, it is recommended that all children with cleft palate should have routine follow-ups by an ENT doctor and audiologist. As part of the routine follow-up care, hearing assessments should be performed before and after VT treatments. Copyright © 2017 Elsevier B.V. All rights reserved.

Composition and similarity of global anomodont-bearing tetrapod faunas

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Fröbisch, Jörg

2009-08-01

Anomodont synapsids represent the dominant herbivores of Permian and Triassic terrestrial vertebrate ecosystems. Their taxonomic diversity and morphological disparity in combination with their cosmopolitan distribution makes them an ideal study object for macroevolutionary patterns across the most devastating extinction event in earth history. This study provides a thorough review of anomodont-bearing tetrapod faunas to form the basis for a faunal similarity analysis and future studies of anomodont diversity. The stratigraphic correlation and composition of all known anomodont assemblages is revisited, including a discussion of the validity of the globally distributed anomodont species. The similarity analysis of anomodont faunas is performed on the basis of presence-absence data of anomodont taxa, using explorative methods such as cluster analysis (UPGMA) and non-metric multidimensional scaling (NMDS). The recovered faunal groupings indicate a common biostratigraphic age and furthermore reflect biogeographic patterns. Even though endemism and faunal provinciality was a constant element in anomodont faunas of the Permian and Triassic, the available evidence indicates that the end-Permian extinction resulted in a distinct uniformity that was unique to Early Triassic anomodont faunas. This is in particular characterized by the global distribution and overwhelming abundance of the disaster taxon Lystrosaurus. In contrast, cosmopolitan anomodonts also existed in the Late Permian (e.g., Diictodon) and Middle Triassic (e.g., Shansiodon), but those taxa coexisted with endemic faunal elements rather than dominated the fauna as Lystrosaurus did.

Presbycusis, part 1: can you hear the music of life?

Science.gov (United States)

Hutchison, Barbara; Covan, Eleanor K; Bogus, Janet C

2012-01-01

We used a novel approach allowing participants in this study to self-monitor their hearing sensitivity to familiar sounds in the environment. The objective of this approach was to establish whether participants in the 80-89 and 90-99 age groups would recognize the degree of their hearing impairment. It was our hope that participants would value audiology treatment and that it would improve their quality of life over a short period. The pilot study took place in a clinical environment where participants answered survey questions before and after audiology treatment, which pertained to their hearing impairment, morale, social support, and life satisfaction. Caregivers were included in the research to rate and record participants' problem behaviors (e.g., shouting, anger, agitation, repetitive speech dialog, and depression) before, during, and after treatment. This research validates other scientists' findings that annoying problem behaviors may actually be the result of hearing loss because of a person's inability to recognize speech. The pilot study shows that participants with mild dementia adapted well to speech and sounds in the natural environment without agitation as well as to management of hearing aids within a 30-day period. The participants with moderate dementia were slower to adapt. All participants with dementia required the cooperation of their caregivers to maintain hygiene of ear canals and hearing aids and insertion. This study suggests that the sooner people receive treatment for hearing loss, the quicker they are to recognize speech and to master hearing aid technology.

Use of Otoacoustic emissions in noise induced hearing loss prevention

CSIR Research Space (South Africa)

Edwards, A

2010-10-01

Full Text Available in laboratory- main clinical use on identification of hearing loss in newborn babies • Clinically sensitive tool for assessing NIHL and the outer hair cells (OHC) • repeatable results • identify cochlear damage before evidenced on an audiogram – normal... audiogram but evidence of OHC loss • Feasible method of evaluating HPD effectiveness using temporary emission shift (TES) • CSIR research developed a prediction model for Hearing Threshold Levels Copy of dancing hair cell.wm © CSIR 2010 Slide 6...

Evaluation of Extended-Wear Hearing Technology for Children with Hearing Loss.

Science.gov (United States)

Wolfe, Jace; Schafer, Erin; Martella, Natalie; Morais, Mila; Mann, Misty

2015-01-01

Research shows that many older children and teenagers who have mild to moderately severe sensorineural hearing loss do not use their hearing instruments during all waking hours. A variety of reasons may contribute toward this problem, including concerns about cosmetics associated with hearing aid use and the inconvenience of daily maintenance associated with hearing instruments. Extended-wear hearing instruments are inserted into the wearer's ear canal by an audiologist and are essentially invisible to outside observers. The goal of this study was to evaluate the potential benefits and limitations associated with use of extended-wear hearing instruments in a group of children with hearing loss. A two-way repeated measures design was used to examine performance differences obtained with the participants' daily-wear hearing instruments versus that obtained with extended-wear hearing instruments. Sixteen children, ages 10-17 yr old, with sensorineural hearing loss ranging from mild to moderately severe. Probe microphone measures were completed to evaluate the aided output of device. Behavioral test measures included word recognition in quiet, sentence recognition in noise, aided warble-tone thresholds, and psychophysical loudness scaling. Questionnaires were also administered to evaluate subjective performance with each hearing technology. Data logging suggested that many participants were not using their daily-wear hearing instruments during all waking hours (mean use was less than 6 h/day). Real ear probe microphone measurements indicated that a closer fit to the Desired Sensation Level Version 5 prescriptive targets was achieved with the children's daily-wear instruments when compared to the extended-wear instruments. There was no statistically significant difference in monosyllabic word recognition at 50 or 60 dBA obtained with the two hearing technologies. Sentence recognition in noise obtained with use of the extended-wear devices was, however, significantly

Congenital hearing impairment

Energy Technology Data Exchange (ETDEWEB)

Robson, Caroline D. [Children' s Hospital and Harvard Medical School, Division of Neuroradiology, Department of Radiology, Boston, MA (United States)

2006-04-15

Establishing the etiology of congenital hearing impairment can significantly improve treatment for certain causes of hearing loss and facilitates genetic counseling. High-resolution CT and MRI have contributed to the evaluation and management of hearing impairment. In addition, with the identification of innumerable genetic loci and genetic defects involved in hearing loss, genetic testing has emerged as an invaluable tool in the assessment of hearing impairment. Some of the common forms of congenital hearing loss are reviewed and their imaging features illustrated. (orig.)

Congenital hearing impairment

International Nuclear Information System (INIS)

Robson, Caroline D.

2006-01-01

Establishing the etiology of congenital hearing impairment can significantly improve treatment for certain causes of hearing loss and facilitates genetic counseling. High-resolution CT and MRI have contributed to the evaluation and management of hearing impairment. In addition, with the identification of innumerable genetic loci and genetic defects involved in hearing loss, genetic testing has emerged as an invaluable tool in the assessment of hearing impairment. Some of the common forms of congenital hearing loss are reviewed and their imaging features illustrated. (orig.)

Preparation of tetrapod-like ZnO/TiO{sub 2} core-shell nanostructures as photocatalytic powder

Energy Technology Data Exchange (ETDEWEB)

Sartori, A.; Visentin, F.; De Zorzi, C.; Natali, M.; Gerbasi, R.; Rossetto, G. [ICIS-DPM-CNR, Padova (Italy); El Habra, N. [ICIS-DPM-CNR, Padova (Italy); Dipartimento di Scienze Chimiche, Padova (Italy); Garoli, D. [Dipartimento di Fisica, Padova (Italy); LANN, Padova (Italy); Casarin, M. [Dipartimento di Scienze Chimiche, Padova (Italy)

2011-08-15

The coupling of zinc oxide tetrapods (t-ZnO) with anatase TiO{sub 2} in the form of CVD coatings on ZnO nanotetrapods was investigated. t-ZnO/TiO{sub 2} core-shell structures, consisting of uniformly and completely TiO{sub 2} covered ZnO nanotetrapods, were characterized by scanning electron microscopy, X-ray diffraction and UV-Vis spectra. Photocatalytic activity, determined by degradation of a sodium methyl red solution, was found to be comparable to pure t-ZnO, while improved separation easiness was verified that makes the presented powders promising for wastewater treatment. (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

CERN hearing day

CERN Multimedia

2005-01-01

1 in 10 people suffer from hearing loss - do you? The Medical Service invites everyone working on the CERN site to participate in the NATIONAL HEARING DAY on: Thursday 10th March 2005 From 9am to 4pm The Infirmary, Blg. 57, Ground Floor We will be offering hearing tests (audiograms), as well as information and advice on hearing loss, tinnitus, etc. Deafness does not just affect the elderly: in Europe, 50% of the hearing-impaired are under the age of 55. Exposure to excessive noise is one of the main reasons for hearing problems but PREVENTION IS POSSIBLE. For example, hearing protection devices can prevent 80% of tinnitus cases.

CERN hearing day

CERN Multimedia

2005-01-01

1 in 10 people suffer from hearing loss - do you? The Medical Service invites everyone working on CERN premises to participate in the National Hearing Day on: Thursday 10th March From 9am to 4pm The Infirmary, Blg. 57, Gr.Fl. We will be offering hearing tests (audiogram); information, advice on hearing loss, tinnitus and more. Deafness does not just affect the elderly: in Europe, 50% the hearing-impaired are under the age of 55. Exposure to excessive noise is one of the main reasons for hearing loss. But PREVENTION IS POSSIBLE AND EFFECTIVE: for example, Hearing protection devices could reduce tinnitus cases by 80%.

CERN hearing day

CERN Document Server

2005-01-01

1 in 10 people suffer from hearing loss - do you? The Medical Service invites everyone working on CERN premises to participate in the National Hearing Day on: Thursday 10th March From 9am to 4pm The Infirmary, Blg. 57, Gr.Fl. We will be offering hearing tests (audiogram); information, advice on hearing loss, tinnitus and more. Deafness does not just affect the elderly: in Europe, 50% the hearing-impaired are under the age of 55. Exposure to excessive noise is one of the main reasons for hearing loss. But prevention is possible and effective: for example, Hearing protection devices could reduce tinnitus cases by 80%.

CERN hearing day

CERN Multimedia

2005-01-01

1 in 10 people suffer from hearing loss ? do you? The Medical Service invites everyone working on the CERN site to participate in the NATIONAL HEARING DAY on: Thursday 10th March 2005 From 9am to 4pm The Infirmary, Blg. 57, Ground Floor We will be offering hearing tests (audiograms), as well as information and advice on hearing loss, tinnitus, etc. Deafness does not just affect the elderly: in Europe, 50% of the hearing-impaired are under the age of 55. Exposure to excessive noise is one of the main reasons for hearing problems but prevention is possible. For example, hearing protection devices can prevent 80% of tinnitus cases.

Hearing Problems

Science.gov (United States)

... Read MoreDepression in Children and TeensRead MoreBMI Calculator Hearing ProblemsLoss in the ability to hear or discriminate ... This flow chart will help direct you if hearing loss is a problem for you or a ...

Comparison of Reading Literacy in Hearing Impaired and Normal Hearing Students

Directory of Open Access Journals (Sweden)

Dr. Ali Asghar Kakojoibari

2011-06-01

Full Text Available Background and Aim: listening, speaking, reading and writing are considered the lingual skills. These skills are in direct relation with each other. Listening is the first skill learnt by the individual through development. If damaged by hearing impairment, listening can cause serious defect to lingual skills. The goal of our research was to study the effect of hearing loss on reading literacy in hearing impairment students in comparison with normal hearing students.Methods: Study was performed using the examination booklets of Progress in International Reading Literacy Study (PIRLS 2001. 119 hearing impairment students of 4th grade primary school, last year guidance school, and last year high school levels in schools providing exceptional student education were included. These individuals were compared to 46 normal hearing students of 4th grade primary school of ordinary schools. Comparative statistical analysis was performed using t-test.Results: Reading literacy and literal contents understanding was shown to have a significant difference between normal hearing and whole hearing impaired student (p<0.05, except the ones in high school level with moderate hearing loss. There was also seen a significant difference between normal hearing and hearing impairment students in understanding of information contents (p=0.03.Conclusion: Hearing loss has a negative effect on reading literacy. Consequently, curriculum change and evolution of educational programs in exceptional centers is needed, in order to promote reading literacy and to enhance rest hearing

Rurality and determinants of hearing healthcare in adult hearing aid recipients.

Science.gov (United States)

Chan, Stephen; Hixon, Brian; Adkins, Margaret; Shinn, Jennifer B; Bush, Matthew L

2017-10-01

The objective of this study was to compare the timing of hearing aid (HA) acquisition between adults in rural and urban communities. We hypothesized that time of acquisition of HA after onset of hearing loss is greater in rural adults compared with urban adults. Secondary objectives included assessment of socioeconomic/educational status and impact of hearing loss and hearing rehabilitation of urban and rural HA recipients. Cross-sectional questionnaire survey. We assessed demographics, timing of HA fitting from onset of hearing loss, and impact of hearing impairment in 336 adult HA recipients (273 urban, 63 rural) from a tertiary referral center. Amplification benefit was assessed using the International Outcome Inventory for Hearing Aids (IOI). The time to HA acquisition was greater for rural participants compared to urban participants (19.1 vs. 25.7 years, P = 0.024) for those with untreated hearing loss for at least 8 years. Age at hearing loss onset was correlated with time to HA acquisition (P = -0.54, P hearing specialists (68 vs. 32 minutes, P Hearing impairment caused job performance difficulty in 60% of all participants. Rural adults are at risk for delayed HA acquisition, which may be related to distance to hearing specialists. Further research is indicated to investigate barriers to care and expand access for vulnerable populations. 4. Laryngoscope, 127:2362-2367, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

Deaf and hard of hearing social workers accessing their profession: a call to action.

Science.gov (United States)

Sheridan, Martha A; White, Barbara J; Mounty, Judith L

2010-01-01

This article aims to familiarize the social work profession with a paradox in its midst. Culturally sensitive and accessible services for deaf and hard of hearing people can often best be provided by social workers who are themselves deaf and hard of hearing, who have specialized language and communication skills, as well as unique cultural knowledge of this population at risk. Yet, deaf and hard of hearing graduates of social work education programs routinely experience difficulties accessing the profession. Addressing this paradox calls for creative collaborations among professional social work organizations, social work education programs, policymakers, and deaf and hard of hearing social workers.

High-frequency Audiometry Hearing on Monitoring of Individuals Exposed to Occupational Noise: A Systematic Review

Directory of Open Access Journals (Sweden)

Antonioli, Cleonice Aparecida Silva

2015-12-01

Full Text Available Introduction The literature reports on high-frequency audiometry as one of the exams used on hearing monitoring of individuals exposed to high sound pressure in their work environment, due to the method́s greater sensitivity in early identification of hearing loss caused by noise. The frequencies that compose the exam are generally between 9 KHz and 20KHz, depending on the equipment. Objective This study aims to perform a retrospective and secondary systematic revision of publications on high-frequency audiometry on hearing monitoring of individuals exposed to occupational noise. Data Synthesis This systematic revision followed the methodology proposed in the Cochrane Handbook, focusing on the question: “Is High-frequency Audiometry more sensitive than Conventional Audiometry in the screening of early hearing loss individuals exposed to occupational noise?” The search was based on PubMed data, Base, Web of Science (Capes, Biblioteca Virtual em Saúde (BVS, and in the references cited in identified and selected articles. The search resulted in 6059 articles in total. Of these, only six studies were compatible with the criteria proposed in this study. Conclusion The performed meta-analysis does not definitively answer the study's proposed question. It indicates that the 16 KHz high frequency audiometry (HFA frequency is sensitive in early identification of hearing loss in the control group (medium difference (MD = 8.33, as well as the 4 KHz frequency (CA, this one being a little less expressive (MD = 5.72. Thus, others studies are necessary to confirm the HFA importance for the early screening of hearing loss on individuals exposed to noise at the workplace.

The tradeoff between signal detection and recognition rules auditory sensitivity under variable background noise conditions.

Science.gov (United States)

Lugli, Marco

2015-12-07

Animal acoustic communication commonly takes place under masked conditions. For instance, sound signals relevant for mating and survival are very often masked by background noise, which makes their detection and recognition by organisms difficult. Ambient noise (AN) varies in level and shape among different habitats, but also remarkable variations in time and space occurs within the same habitat. Variable AN conditions mask hearing thresholds of the receiver in complex and unpredictable ways, thereby causing distortions in sound perception. When communication takes place in a noisy environment, a highly sensitive system might confer no advantage to the receiver compared to a less sensitive one. The effects of noise masking on auditory thresholds and hearing-related functions are well known, and the potential role of AN in the evolution of the species' auditory sensitivity has been recognized by few authors. The mechanism of the underlying selection process has never been explored, however. Here I present a simple fitness model that seeks for the best sensitivity of a hearing system performing the detection and recognition of the sound under variable AN conditions. The model predicts higher sensitivity (i.e. lower hearing thresholds) as best strategy for species living in quiet habitats and lower sensitivity (i.e. higher hearing thresholds) as best strategy for those living in noisy habitats provided the cost of incorrect recognition is not low. The tradeoff between detection and recognition of acoustic signals appears to be a key factor determining the best level of hearing sensitivity of a species when acoustic communication is corrupted by noise. Copyright © 2015 Elsevier Ltd. All rights reserved.

Hearing capacities and otolith size in two ophidiiform species (Ophidion rochei and Carapus acus).

Science.gov (United States)

Kéver, Loïc; Colleye, Orphal; Herrel, Anthony; Romans, Pascal; Parmentier, Eric

2014-07-15

Numerous studies have highlighted the diversity of fish inner ear morphology. However, the function of the shape, size and orientation of the different structures remains poorly understood. The saccule (otolithic endorgan) is considered to be the principal hearing organ in fishes and it has been hypothesized that sagitta (saccular otolith) shape and size affect hearing capacities: large sagittae are thought to increase sensitivity. The sagittae of many ophidiids and carapids occupy a large volume inside the neurocranium. Hence they are a good structure with which to test the size hypothesis. The main aim of this study was to investigate hearing capacities and inner ear morphology in two ophidiiform species: Ophidion rochei and Carapus acus. We used a multidisciplinary approach that combines dissections, μCT-scan examinations and auditory evoked potential techniques. Carapus acus and O. rochei sagittae have similar maximal diameters; both species have larger otoliths than many non-ophidiiform species, especially compared with the intra-neurocranium volume. Both species are sensitive to sounds up to 2100 Hz. Relative to the skull, O. rochei has smaller sagittae than the carapid, but better hearing capacities from 300 to 900 Hz and similar sensitivities at 150 Hz and from 1200 to 2100 Hz. Results show that hearing capacities of a fish species cannot be predicted only based on sagitta size. Larger otoliths (in size relative to the skull) may have evolved mainly for performing vestibular functions in fishes, especially those species that need to execute precise and complex movements. © 2014. Published by The Company of Biologists Ltd.

Enhancing light emission in flexible AC electroluminescent devices by tetrapod-like zinc oxide whiskers.

Science.gov (United States)

Wen, Li; Liu, Nishuang; Wang, Siliang; Zhang, Hui; Zhao, Wanqiu; Yang, Zhichun; Wang, Yumei; Su, Jun; Li, Luying; Long, Fei; Zou, Zhengguang; Gao, Yihua

2016-10-03

Flexible alternating current electroluminescent devices (ACEL) are more and more popular and widely used in liquid-crystal display back-lighting, large-scale architectural and decorative lighting due to their uniform light emission, low power consumption and high resolution. However, presently how to acquire high brightness under a certain voltage are confronted with challenges. Here, we demonstrate an electroluminescence (EL) enhancing strategy that tetrapod-like ZnO whiskers (T-ZnOw) are added into the bottom electrode of carbon nanotubes (CNTs) instead of phosphor layer in flexible ACEL devices emitting blue, green and orange lights, and the brightness is greatly enhanced due to the coupling between the T-ZnOw and ZnS phosphor dispersed in the flexible polydimethylsiloxane (PDMS) layer. This strategy provides a new routine for the development of high performance, flexible and large-area ACEL devices.

Can Baby Hear?

Science.gov (United States)

... born in the United States are deaf or hard-of-hearing. Research shows that early intervention with hearing devices and educational services can help children with hearing loss to develop language skills at the same rate as their hearing peers. ...

Effects of age and hearing loss on recognition of unaccented and accented multisyllabic words

Science.gov (United States)

Gordon-Salant, Sandra; Yeni-Komshian, Grace H.; Fitzgibbons, Peter J.; Cohen, Julie I.

2015-01-01

The effects of age and hearing loss on recognition of unaccented and accented words of varying syllable length were investigated. It was hypothesized that with increments in length of syllables, there would be atypical alterations in syllable stress in accented compared to native English, and that these altered stress patterns would be sensitive to auditory temporal processing deficits with aging. Sets of one-, two-, three-, and four-syllable words with the same initial syllable were recorded by one native English and two Spanish-accented talkers. Lists of these words were presented in isolation and in sentence contexts to younger and older normal-hearing listeners and to older hearing-impaired listeners. Hearing loss effects were apparent for unaccented and accented monosyllabic words, whereas age effects were observed for recognition of accented multisyllabic words, consistent with the notion that altered syllable stress patterns with accent are sensitive for revealing effects of age. Older listeners also exhibited lower recognition scores for moderately accented words in sentence contexts than in isolation, suggesting that the added demands on working memory for words in sentence contexts impact recognition of accented speech. The general pattern of results suggests that hearing loss, age, and cognitive factors limit the ability to recognize Spanish-accented speech. PMID:25698021

Auditory brainstem response screening for hearing loss in high risk neonates.

Science.gov (United States)

Watson, D R; McClelland, R J; Adams, D A

1996-07-01

The present paper reports the findings of a 7 year study evaluating the use of the auditory brainstem response (ABR) as the basis of a hearing screening procedure in a group of newborns at increased risk of hearing impairment. A Special Care Baby Unit (SCBU) population of 417 infants with diverse clinical backgrounds and treatment histories was tested for hearing impairment at birth using ABR audiometry. Some 332 passed the original screen at 30 dBnHL test level in both ears. Of the failure group, 18 did not survive and 32 had some degree of hearing impairment confirmed, nine of which were sensorineural in origin. An increased incidence of persistent middle ear disease was also noted in the failure group. A detailed operational analysis demonstrates that provided appropriate pass/fail criteria are adopted, the ABR technique offers excellent sensitivity and specificity for the detection of significant hearing loss in the test population. Furthermore, the study establishes that implementation of an ABR-based screening programme could reduce the average age at detection of permanent hearing loss by 7 months. A cost assessment shows that the introduction of such a targetted screening procedure could be done at a reasonable outlay.

Conductive hearing loss and bone conduction devices: restored binaural hearing?

Science.gov (United States)

Agterberg, Martijn J H; Hol, Myrthe K S; Cremers, Cor W R J; Mylanus, Emmanuel A M; van Opstal, John; Snik, Ad F M

2011-01-01

An important aspect of binaural hearing is the proper detection of interaural sound level differences and interaural timing differences. Assessments of binaural hearing were made in patients with acquired unilateral conductive hearing loss (UCHL, n = 11) or congenital UCHL (n = 10) after unilateral application of a bone conduction device (BCD), and in patients with bilateral conductive or mixed hearing loss after bilateral BCD application. Benefit (bilateral versus unilateral listening) was assessed by measuring directional hearing, compensation of the acoustic head shadow, binaural summation and binaural squelch. Measurements were performed after an acclimatization time of at least 10 weeks. Unilateral BCD application was beneficial, but there was less benefit in the patients with congenital UCHL as compared to patients with acquired UCHL. In adults with bilateral hearing loss, bilateral BCD application was clearly beneficial as compared to unilateral BCD application. Binaural summation was present, but binaural squelch could not be proven. To explain the poor results in the patients with congenital UCHL, two factors seemed to be important. First, a critical period in the development of binaural hearing might affect the binaural hearing abilities. Second, crossover stimulation, referring to additional stimulation of the cochlea contralateral to the BCD side, might deteriorate binaural hearing in patients with UCHL. Copyright © 2011 S. Karger AG, Basel.

Selective Inner Hair Cell Dysfunction in Chinchillas Impairs Hearing-in-Noise in the Absence of Outer Hair Cell Loss.

Science.gov (United States)

Lobarinas, Edward; Salvi, Richard; Ding, Dalian

2016-04-01

Poorer hearing in the presence of background noise is a significant problem for the hearing impaired. Ototoxic drugs, ageing, and noise exposure can damage the sensory hair cells of the inner ear that are essential for normal hearing sensitivity. The relationship between outer hair cell (OHC) loss and progressively poorer hearing sensitivity in quiet or in competing background noise is supported by a number of human and animal studies. In contrast, the effect of moderate inner hair cell (IHC) loss or dysfunction shows almost no impact on behavioral measures of hearing sensitivity in quiet, when OHCs remain intact, but the relationship between selective IHC loss and hearing in noise remains relatively unknown. Here, a moderately high dose of carboplatin (75 mg/kg) that produced IHC loss in chinchillas ranging from 40 to 80 % had little effect on thresholds in quiet. However, when tested in the presence of competing broadband (BBN) or narrowband noise (NBN), thresholds increased significantly. IHC loss >60 % increased signal-to-noise ratios (SNRs) for tones (500-11,300 Hz) in competing BBN by 5-10 dB and broadened the masking function under NBN. These data suggest that IHC loss or dysfunction may play a significant role in listening in noise independent of OHC integrity and that these deficits may be present even when thresholds in quiet are within normal limits.

Hearing in young adults. Part I: The effects of attitudes and beliefs toward noise, hearing loss, and hearing protector devices

Directory of Open Access Journals (Sweden)

Hannah Keppler

2015-01-01

Full Text Available There is great concern regarding the development of noise-induced hearing loss (NIHL in youth caused by high sound levels during various leisure activities. Health-orientated behavior of young adults might be linked to the beliefs and attitudes toward noise, hearing loss, and hearing protector devices (HPDs. The objective of the current study was to evaluate the effects of attitudes and beliefs toward noise, hearing loss, and HPDs on young adults′ hearing status. A questionnaire and an audiological test battery were completed by 163 subjects (aged 18-30 years. The questionnaire contained the Youth Attitude to Noise Scale (YANS and Beliefs about Hearing Protection and Hearing Loss (BAHPHL. A more positive attitude or belief represented an attitude where noise or hearing loss is seen as unproblematic and attitudes and beliefs regarding HPDs is worse. Hearing was evaluated using (high frequency pure tone audiometry (PTA, transient evoked and distortion product otoacoustic emissions. First, mean differences in hearing between the groups with different attitudes and beliefs were evaluated using one-way analysis of variance (ANOVA. Second, a χ2 test was used to examine the usage of HPDs by the different groups with different attitudes and beliefs. Young adults with a positive attitude had significantly more deteriorated hearing and used HPDs less than the other subjects. Hearing conservation programs (HCPs for young adults should provide information and knowledge regarding noise, hearing loss, and HPDs. Barriers wearing HPDs should especially be discussed. Further, those campaigns should focus on self-experienced hearing related symptoms that might serve as triggers for attitudinal and behavioral changes.

Hearing Protection and Hearing Symptoms in Danish Symphony Orchestras

DEFF Research Database (Denmark)

Laitinen, Heli; Poulsen, Torben

2006-01-01

A study about hearing protectors, problems involving hearing protector usage, hearing problems and working surroundings of classical musicians was made in three Danish symphony orchestras. The questionnaire used in the study was based on a previous study, a study made in Sweden to rock musicians,...

Hard of Hearing?

DEFF Research Database (Denmark)

T Christensen, Vibeke

This summary presents the results of a study of the impact of reduced hearing in relation to labour-market attachment and working life. Reduced hearing contributes to early retirement. Many people with impaired hearing are not aware of the impact of their hearing problems on their working life an...

Treatment Efficacy: Hearing Aids in the Management of Hearing Loss in Adults.

Science.gov (United States)

Weinstein, Barbara E.

1996-01-01

This article reviews the efficacy of hearing aids in adults with hearing impairments. Information is provided on the prevalence of hearing impairments; the daily effects of a hearing impairment; and the role of the audiologist. The effectiveness and benefits of hearing aids are reviewed, and a case study is provided. (CR)

EchoScan: A new system to objectively assess peripheral hearing disorders

Directory of Open Access Journals (Sweden)

Thomas Venet

2012-01-01

Full Text Available Pure-tone air-conduction audiometry (PTA is the reference clinical test used in Europe and the United States to measure the extent of hearing loss. It is a subjective, behavioral test, which measures thresholds of hearing sensations and perceptions based on patient responses to frequency-specific pure-tone stimuli. PTA can detect hearing problems due to cochlear or retro-cochlear impairment, without identifying the source of the problem. In contrast, cubic distortion product otoacoustic emissions (DPOAEs detect inner-ear dysfunctions, particularly those involving the outer hair cells sensitive to noise and ototoxicants. Recently, ototoxicants were shown to have an action on the central nuclei driving the middle-ear acoustic reflex. Therefore, a new device, called EchoScan, was conceived to collect and measure performance both in the middle- and inner-ear. Its originality: the use of a battery of DPOAE measurements associated with contra-lateral acoustic stimulation. Changes in DPOAE amplitude due to ageing and gender were incidentally detected and EchoScan was more sensitive than impedancemetry to detect the stapedial reflex. EchoScan can be used both in clinical investigations and in occupational medicine, especially for the auditory follow-up of people exposed to noise or ototoxic agents. EchoScan could be promising to assess early detection in programs to prevent hearing loss.

Effect of musical training on pitch discrimination performance in older normal-hearing and hearing-impaired listeners

DEFF Research Database (Denmark)

Bianchi, Federica; Dau, Torsten; Santurette, Sébastien

2017-01-01

-discrimination performance for NH listeners. It is unclear whether a comparable effect of musical training occurs for listeners whose sensory encoding of F0 is degraded. To address this question, F0 discrimination was investigated for three groups of listeners (14 young NH, 9 older NH and 10 HI listeners), each......Hearing-impaired (HI) listeners, as well as elderly listeners, typically have a reduced ability to discriminate the fundamental frequency (F0) of complex tones compared to young normal-hearing (NH) listeners. Several studies have shown that musical training, on the other hand, leads to improved F0...... including musicians and non-musicians, using complex tones that differed in harmonic content. Musical training significantly improved F0 discrimination for all groups of listeners, especially for complex tones containing low-numbered harmonics. In a second experiment, the sensitivity to temporal fine...

Anatomy and physiology of binaural hearing.

Science.gov (United States)

Moore, D R

1991-01-01

Binaural hearing improves performance in most auditory tasks and is essential for some. This paper introduces the brain stem pathways and nuclei involved in binaural interaction and outlines some recent approaches to understanding binaural mechanisms. It also provides examples of basic science approaches to the effects of infant hearing loss on those pathways and mechanisms. Binaural interaction occurs primarily and almost simultaneously at three levels of the brain: the superior olivary complex (SOC), the nuclei of the lateral lemniscus (NLL) and the inferior colliculus (IC). The SOC derives its input from the anterior ventral cochlear nucleus (CN) through branching axons that innervate several SOC subdivisions on both sides of the brain. At least some of these anteroventral CN axons project on up to the contralateral NLL and IC. The IC and NLL also receive direct, major projections from the contralateral CN, via the dorsal and intermediate acoustic striae, and from the SOC bilaterally. The IC receives additional input from the NLL bilaterally, and is thus innervated by every nuclear group within the auditory brain stem. There is little evidence for strict, functional segregation in these binaural pathways, although subdivisions of the SOC appear to be predominantly involved in analysing either interaural time or level differences (ITD, ILD). ITD- and ILD-sensitive neurones are also found in abundance in the central IC. There is emerging evidence that binaural information is coupled with spectral cues derived from the outer ear in several auditory mid-brain regions [the NLL, the external IC and the superior colliculus (SC)] to produce topographic representations of auditory space. Throughout the higher auditory system the response of neurones to stimulation of each ear is either excitatory or inhibitory, and there is a spatial segregation of neurones receiving predominantly excitatory or inhibitory input from the ipsilateral ear in both the medial geniculate body

Smartphone-based audiometric test for screening hearing loss in the elderly.

Science.gov (United States)

Abu-Ghanem, Sara; Handzel, Ophir; Ness, Lior; Ben-Artzi-Blima, Miri; Fait-Ghelbendorf, Karin; Himmelfarb, Mordechai

2016-02-01

Hearing loss is widespread among the elderly. One of the main obstacles to rehabilitation is identifying individuals with potentially correctable hearing loss. Smartphone-based hearing tests can be administered at home, thus greatly facilitating access to screening. This study evaluates the use of a smartphone application as a screening tool for hearing loss in individuals aged ≥ 65 years. Twenty-six subjects aged 84.4 ± 6.73 years (mean ± SD) were recruited. Pure-tone audiometry was administered by both a smartphone application (uHear for iPhone, v1.0 Unitron, Canada) and a standard portable audiometer by trained personnel. Participants also completed a questionnaire on their hearing. Pure-tone thresholds were compared between the two testing modalities and correlated with the questionnaire results. The cutoff point for failing screening tests was a pure tone average of 40 dB for the frequencies 250-6,000 Hz. The smartphone application's pure tone thresholds were higher (poorer hearing) than the audiometric thresholds, with a significant difference in all frequencies but 2,000 Hz. The application and the audiometric values were in agreement for 24 subjects (92 %). The application had a sensitivity of 100 % and specificity of 60 % for screening compared with the audiometer. The questionnaire was significantly less accurate, having assigned a passing score to three participants who failed both the application and audiometric tests. While a smartphone application may not be able to accurately determine the level of hearing impairment, it is useful as a highly accessible portable audiometer substitute for screening for hearing loss in elderly populations.

Auditory analysis of xeroderma pigmentosum 1971–2012: hearing function, sun sensitivity and DNA repair predict neurological degeneration

Science.gov (United States)

Totonchy, Mariam B.; Tamura, Deborah; Pantell, Matthew S.; Zalewski, Christopher; Bradford, Porcia T.; Merchant, Saumil N.; Nadol, Joseph; Khan, Sikandar G.; Schiffmann, Raphael; Pierson, Tyler Mark; Wiggs, Edythe; Griffith, Andrew J.; DiGiovanna, John J.; Brewer, Carmen C.

2013-01-01

To assess the role of DNA repair in maintenance of hearing function and neurological integrity, we examined hearing status, neurological function, DNA repair complementation group and history of acute burning on minimal sun exposure in all patients with xeroderma pigmentosum, who had at least one complete audiogram, examined at the National Institutes of Health from 1971 to 2012. Seventy-nine patients, aged 1–61 years, were diagnosed with xeroderma pigmentosum (n = 77) or xeroderma pigmentosum/Cockayne syndrome (n = 2). A total of 178 audiograms were included. Clinically significant hearing loss (>20 dB) was present in 23 (29%) of 79 patients. Of the 17 patients with xeroderma pigmentosum-type neurological degeneration, 13 (76%) developed hearing loss, and all 17 were in complementation groups xeroderma pigmentosum type A or type D and reported acute burning on minimal sun exposure. Acute burning on minimal sun exposure without xeroderma pigmentosum-type neurological degeneration was present in 18% of the patients (10/55). Temporal bone histology in a patient with severe xeroderma pigmentosum-type neurological degeneration revealed marked atrophy of the cochlear sensory epithelium and neurons. The 19-year mean age of detection of clinically significant hearing loss in the patients with xeroderma pigmentosum with xeroderma pigmentosum-type neurological degeneration was 54 years younger than that predicted by international norms. The four frequency (0.5/1/2/4 kHz) pure-tone average correlated with degree of neurodegeneration (P xeroderma pigmentosum, aged 4–30 years, a four-frequency pure-tone average ≥10 dB hearing loss was associated with a 39-fold increased risk (P = 0.002) of having xeroderma pigmentosum-type neurological degeneration. Severity of hearing loss parallels neurological decline in patients with xeroderma pigmentosum-type neurological degeneration. Audiometric findings, complementation group, acute burning on minimal sun exposure and age were

Binaural pitch perception in normal-hearing and hearing-impaired listeners

DEFF Research Database (Denmark)

Santurette, Sébastien; Dau, Torsten

2007-01-01

The effects of hearing impairment on the perception of binaural-pitch stimuli were investigated. Several experiments were performed with normal-hearing and hearing-impaired listeners, including detection and discrimination of binaural pitch, and melody recognition using different types of binaural...... pitches. For the normal-hearing listeners, all types of binaural pitches could be perceived immediately and were musical. The hearing-impaired listeners could be divided into three groups based on their results: (a) some perceived all types of binaural pitches, but with decreased salience or musicality...... compared to normal-hearing listeners; (b) some could only perceive the strongest pitch types; (c) some were unable to perceive any binaural pitch at all. The performance of the listeners was not correlated with audibility. Additional experiments investigated the correlation between performance in binaural...

Toxicity of functional nano-micro zinc oxide tetrapods: impact of cell culture conditions, cellular age and material properties.

Science.gov (United States)

Papavlassopoulos, Heike; Mishra, Yogendra K; Kaps, Sören; Paulowicz, Ingo; Abdelaziz, Ramzy; Elbahri, Mady; Maser, Edmund; Adelung, Rainer; Röhl, Claudia

2014-01-01

With increasing production and applications of nanostructured zinc oxide, e.g., for biomedical and consumer products, the question of safety is getting more and more important. Different morphologies of zinc oxide structures have been synthesized and accordingly investigated. In this study, we have particularly focused on nano-micro ZnO tetrapods (ZnO-T), because their large scale fabrication has been made possible by a newly introduced flame transport synthesis approach which will probably lead to several new applications. Moreover, ZnO-T provide a completely different morphology then classical spherical ZnO nanoparticles. To get a better understanding of parameters that affect the interactions between ZnO-T and mammalian cells, and thus their biocompatibility, we have examined the impact of cell culture conditions as well as of material properties on cytotoxicity. Our results demonstrate that the cell density of fibroblasts in culture along with their age, i.e., the number of preceding cell divisions, strongly affect the cytotoxic potency of ZnO-T. Concerning the material properties, the toxic potency of ZnO-T is found to be significantly lower than that of spherical ZnO nanoparticles. Furthermore, the morphology of the ZnO-T influenced cellular toxicity in contrast to surface charges modified by UV illumination or O2 treatment and to the material age. Finally, we have observed that direct contact between tetrapods and cells increases their toxicity compared to transwell culture models which allow only an indirect effect via released zinc ions. The results reveal several parameters that can be of importance for the assessment of ZnO-T toxicity in cell cultures and for particle development.

The Master Hearing Aid

Science.gov (United States)

Curran, James R.

2013-01-01

As early as the 1930s the term Master Hearing Aid (MHA) described a device used in the fitting of hearing aids. In their original form, the MHA was a desktop system that allowed for simulated or actual adjustment of hearing aid components that resulted in a changed hearing aid response. Over the years the MHA saw many embodiments and contributed to a number of rationales for the fitting of hearing aids. During these same years, the MHA was viewed by many as an inappropriate means of demonstrating hearing aids; the audio quality of the desktop systems was often superior to the hearing aids themselves. These opinions and the evolution of the MHA have molded the modern perception of hearing aids and the techniques used in the fitting of hearing aids. This article reports on a history of the MHA and its influence on the fitting of hearing aids. PMID:23686682

Hearing in the Juvenile Green Sea Turtle (Chelonia mydas: A Comparison of Underwater and Aerial Hearing Using Auditory Evoked Potentials.

Directory of Open Access Journals (Sweden)

Wendy E D Piniak

Full Text Available Sea turtles spend much of their life in aquatic environments, but critical portions of their life cycle, such as nesting and hatching, occur in terrestrial environments, suggesting that it may be important for them to detect sounds in both air and water. In this study we compared underwater and aerial hearing sensitivities in five juvenile green sea turtles (Chelonia mydas by measuring auditory evoked potential responses to tone pip stimuli. Green sea turtles detected acoustic stimuli in both media, responding to underwater stimuli between 50 and 1600 Hz and aerial stimuli between 50 and 800 Hz, with maximum sensitivity between 200 and 400 Hz underwater and 300 and 400 Hz in air. When underwater and aerial hearing sensitivities were compared in terms of pressure, green sea turtle aerial sound pressure thresholds were lower than underwater thresholds, however they detected a wider range of frequencies underwater. When thresholds were compared in terms of sound intensity, green sea turtle sound intensity level thresholds were 2-39 dB lower underwater particularly at frequencies below 400 Hz. Acoustic stimuli may provide important environmental cues for sea turtles. Further research is needed to determine how sea turtles behaviorally and physiologically respond to sounds in their environment.

Viral Causes of Hearing Loss: A Review for Hearing Health Professionals

Science.gov (United States)

Cohen, Brandon E.; Durstenfeld, Anne

2014-01-01

A number of viral infections can cause hearing loss. Hearing loss induced by these viruses can be congenital or acquired, unilateral or bilateral. Certain viral infections can directly damage inner ear structures, others can induce inflammatory responses which then cause this damage, and still others can increase susceptibility or bacterial or fungal infection, leading to hearing loss. Typically, virus-induced hearing loss is sensorineural, although conductive and mixed hearing losses can be seen following infection with certain viruses. Occasionally, recovery of hearing after these infections can occur spontaneously. Most importantly, some of these viral infections can be prevented or treated. For many of these viruses, guidelines for their treatment or prevention have recently been revised. In this review, we outline many of the viruses that cause hearing loss, their epidemiology, course, prevention, and treatment. PMID:25080364

Enhancing Ear and Hearing Health Access for Children With Technology and Connectivity.

Science.gov (United States)

Swanepoel, De Wet

2017-10-12

Technology and connectivity advances are demonstrating increasing potential to improve access of service delivery to persons with hearing loss. This article demonstrates use cases from community-based hearing screening and automated diagnosis of ear disease. This brief report reviews recent evidence for school- and home-based hearing testing in underserved communities using smartphone technologies paired with calibrated headphones. Another area of potential impact facilitated by technology and connectivity is the use of feature extraction algorithms to facilitate automated diagnosis of most common ear conditions from video-otoscopic images. Smartphone hearing screening using calibrated headphones demonstrated equivalent sensitivity and specificity for school-based hearing screening. Automating test sequences with a forced-choice response paradigm allowed persons with minimal training to offer screening in underserved communities. The automated image analysis and diagnosis system for ear disease demonstrated an overall accuracy of 80.6%, which is up to par and exceeds accuracy rates previously reported for general practitioners and pediatricians. The emergence of these tools that capitalize on technology and connectivity advances enables affordable and accessible models of service delivery for community-based ear and hearing care.

Diagnostic utility of the acoustic reflex in predicting hearing in paediatric populations.

Science.gov (United States)

Pérez-Villa, Yolanda E; Mena-Ramírez, María E; Aguirre, Laura E Chamlati; Mora-Magaña, Ignacio; Gutiérrez-Farfán, Ileana S

2014-01-01

The sensitivity of prediction of acoustic reflex, in determining the level of hearing loss, is especially useful in paediatric populations. It is based on the difference between the pure tone stapedius reflex threshold and contralateral white noise. The white noise threshold was 60 dB and that of pure tone was 80 dB. Our objective was to determine the diagnostic sensitivity of the prediction of the acoustic reflex. We studied children aged <10 years, from October 2011 to May 2012, by measuring the acoustic reflex with white noise and pure tone. We used contrast tests, with X2 and student t-test. Concordance was measured with Kappa. Results were considered significant at P≤.05. Our protocol was approved by Institutional Ethics Committee. Informed consent was obtained from the parents in all cases. Prediction of normal hearing was 0.84 for the right ear and 0.78 in left ear, while for hearing loss of an unspecified grade, it was 0.98 for the right ear and 0.96 in the left ear. Kappa value was 0.7 to 0.6 for the right ear and left ear. The acoustic reflex is of little diagnostic utility in predicting the degree of hearing loss, but it predicts more than 80% of normal hearing. The clinical utility of the reflex is indisputable, as it is an objective method, simple and rapid to use, that can be performed from birth and whose results are independent of the cooperation and willingness of the subject. It is proposed as an obligatory part of hearing screening. Copyright © 2013 Elsevier España, S.L.U. y Sociedad Española de Otorrinolaringología y Patología Cérvico-Facial. All rights reserved.

Ontogenetic investigation of underwater hearing capabilities in loggerhead sea turtles (Caretta caretta) using a dual testing approach.

Science.gov (United States)

Lavender, Ashley L; Bartol, Soraya M; Bartol, Ian K

2014-07-15

Sea turtles reside in different acoustic environments with each life history stage and may have different hearing capacity throughout ontogeny. For this study, two independent yet complementary techniques for hearing assessment, i.e. behavioral and electrophysiological audiometry, were employed to (1) measure hearing in post-hatchling and juvenile loggerhead sea turtles Caretta caretta (19-62 cm straight carapace length) to determine whether these migratory turtles exhibit an ontogenetic shift in underwater auditory detection and (2) evaluate whether hearing frequency range and threshold sensitivity are consistent in behavioral and electrophysiological tests. Behavioral trials first required training turtles to respond to known frequencies, a multi-stage, time-intensive process, and then recording their behavior when they were presented with sound stimuli from an underwater speaker using a two-response forced-choice paradigm. Electrophysiological experiments involved submerging restrained, fully conscious turtles just below the air-water interface and recording auditory evoked potentials (AEPs) when sound stimuli were presented using an underwater speaker. No significant differences in behavior-derived auditory thresholds or AEP-derived auditory thresholds were detected between post-hatchling and juvenile sea turtles. While hearing frequency range (50-1000/1100 Hz) and highest sensitivity (100-400 Hz) were consistent in audiograms pooled by size class for both behavior and AEP experiments, both post-hatchlings and juveniles had significantly higher AEP-derived than behavior-derived auditory thresholds, indicating that behavioral assessment is a more sensitive testing approach. The results from this study suggest that post-hatchling and juvenile loggerhead sea turtles are low-frequency specialists, exhibiting little differences in threshold sensitivity and frequency bandwidth despite residence in acoustically distinct environments throughout ontogeny. © 2014

Exploring the influence of culture on hearing help-seeking and hearing-aid uptake.

Science.gov (United States)

Zhao, Fei; Manchaiah, Vinaya; St Claire, Lindsay; Danermark, Berth; Jones, Lesley; Brandreth, Marian; Krishna, Rajalakshmi; Goodwin, Robin

2015-07-01

The purpose of this paper was to highlight the importance of cultural influence in understanding hearing-help seeking and hearing-aid uptake. Information on audiological services in different countries and 'theories related to cross-culture' is presented, followed by a general discussion. Twenty-seven relevant literature reviews on hearing impairment, cross-cultural studies, and the health psychology model and others as secondary resources. Despite the adverse consequences of hearing impairment and the significant potential benefits of audiological rehabilitation, only a small number of those with hearing impairment seek professional help and take up appropriate rehabilitation. Therefore, hearing help-seeking and hearing-aid uptake has recently become the hot topic for clinicians and researchers. Previous research has identified many contributing factors for hearing help-seeking with self-reported hearing disability being one of the main factors. Although significant differences in help-seeking and hearing-aid adoption rates have been reported across countries in population studies, limited literature on the influence of cross-cultural factors in this area calls for an immediate need for research. This paper highlights the importance of psychological models and cross-cultural research in the area of hearing help-seeking and hearing-aid uptake, and consequently some directions for future research are proposed.

Sensorineural hearing loss associated with occupational noise exposure: effects of age-corrections.

Science.gov (United States)

Krishnamurti, Sridhar

2009-03-01

Noise-induced permanent threshold shifts (NIPTS) were computed from retrospective audiometric analyses by subtracting aging effects on hearing sensitivity in sixty-eight patients with bilateral sensorineural hearing loss who reported significant occupational noise exposure histories. There were significant effects of age on NIPTS but no significant gender- or ear- differences in terms of NIPTS. The NIPTS at 2,000 Hz was found to be significantly greater than NIPTS at frequencies 500 Hz, 1,000 Hz, 4,000 Hz, and 8,000 Hz. Defined noise notches were seen in the audiograms of 38/136 (27%) ears with SNHL. Results support models that suggest interactive effects of aging and noise on sensorineural hearing loss in ears with occupational noise exposure.

Low empathy in deaf and hard of hearing (preadolescents compared to normal hearing controls.

Directory of Open Access Journals (Sweden)

Anouk P Netten

Full Text Available The purpose of this study was to examine the level of empathy in deaf and hard of hearing (preadolescents compared to normal hearing controls and to define the influence of language and various hearing loss characteristics on the development of empathy.The study group (mean age 11.9 years consisted of 122 deaf and hard of hearing children (52 children with cochlear implants and 70 children with conventional hearing aids and 162 normal hearing children. The two groups were compared using self-reports, a parent-report and observation tasks to rate the children's level of empathy, their attendance to others' emotions, emotion recognition, and supportive behavior.Deaf and hard of hearing children reported lower levels of cognitive empathy and prosocial motivation than normal hearing children, regardless of their type of hearing device. The level of emotion recognition was equal in both groups. During observations, deaf and hard of hearing children showed more attention to the emotion evoking events but less supportive behavior compared to their normal hearing peers. Deaf and hard of hearing children attending mainstream education or using oral language show higher levels of cognitive empathy and prosocial motivation than deaf and hard of hearing children who use sign (supported language or attend special education. However, they are still outperformed by normal hearing children.Deaf and hard of hearing children, especially those in special education, show lower levels of empathy than normal hearing children, which can have consequences for initiating and maintaining relationships.

Mathematics Motivation, Anxiety, and Performance in Female Deaf/Hard-of-Hearing and Hearing Students

Science.gov (United States)

Ariapooran, Saeed

2017-01-01

Hearing loss can be a major detriment to academic achievement among students. The present comparative study examines the differences in mathematics motivation, anxiety, and performance in female students with hearing loss and their hearing peers. A total of 63 female students with hearing loss (deaf and hard-of-hearing) and 63 hearing female…

Early Hearing Detection and Intervention: Can Your Baby Hear?

Centers for Disease Control (CDC) Podcasts

This podcast discusses how important it is that every child receives a hearing screening as soon as possible after birth. It also gives specific ways that parents and health providers can find out if a child has a possible hearing loss and where to get further information. (Created 6/5/2007 by the Early Hearing Detection and Intervention Program, NCBDDD).

Sensori-neural hearing loss in patients treated with irradiation for nasopharyngeal carcinoma

International Nuclear Information System (INIS)

Grau, C.; Moller, K.; Overgaard, M.; Overgaard, J.; Elbrond, O.

1991-01-01

The present investigation has been carried out to evaluate the sensitivity of the inner ear to irradiation. Cochlear function was tested in a cohort of 22 patients before and 7-84 months after receiving external irradiation for nasopharyngeal carcinoma. The pre-irradiation sensori-neural hearing threshold at 500, 1000, 2000, and 4000 Hz was used as a baseline for the individual patient, and the observed sensori-neural hearing loss (SNHL) was calculated as the difference between pre- and post-irradiation values. The pre-irradiation hearing level or patient age was not correlated with the actual SNHL. In contrast, there was a significant correlation between the total radiation dose to the inner ear and the observed hearing impairment. SNHL was most pronounced in the high frequencies, with values up to 35 dB (4000 Hz) and 25 dB (2000 Hz) in some patients. The latent period for the complication appeared to be 12 months or more. The deleterious effect of irradiation on the hearing should be kept in mind both in treatment planning and in the follow-up after radiotherapy

A user-operated test of suprathreshold acuity in noise for adult hearing screening: The SUN (Speech Understanding in Noise) test.

Science.gov (United States)

Paglialonga, Alessia; Tognola, Gabriella; Grandori, Ferdinando

2014-09-01

A novel, user-operated test of suprathreshold acuity in noise for use in adult hearing screening (AHS) was developed. The Speech Understanding in Noise test (SUN) is a speech-in-noise test that makes use of a list of vowel-consonant-vowel (VCV) stimuli in background noise presented in a three-alternative forced choice (3AFC) paradigm by means of a touch sensitive screen. The test is automated, easy-to-use, and provides self-explanatory results (i.e., 'no hearing difficulties', or 'a hearing check would be advisable', or 'a hearing check is recommended'). The test was developed from its building blocks (VCVs and speech-shaped noise) through two main steps: (i) development of the test list through equalization of the intelligibility of test stimuli across the set and (ii) optimization of the test results through maximization of the test sensitivity and specificity. The test had 82.9% sensitivity and 85.9% specificity compared to conventional pure-tone screening, and 83.8% sensitivity and 83.9% specificity to identify individuals with disabling hearing impairment. Results obtained so far showed that the test could be easily performed by adults and older adults in less than one minute per ear and that its results were not influenced by ambient noise (up to 65dBA), suggesting that the test might be a viable method for AHS in clinical as well as non-clinical settings. Copyright © 2014 Elsevier Ltd. All rights reserved.

Impact of OSHA Final Rule—Recording Hearing Loss: An Analysis of an Industrial Audiometric Dataset

Science.gov (United States)

Rabinowitz, Peter M.; Slade, Martin; Dixon-Ernst, Christine; Sircar, Kanta; Cullen, Mark

2013-01-01

The 2003 Occupational Safety and Health Administration (OSHA) Occupational Injury and Illness Recording and Reporting Final Rule changed the definition of recordable work-related hearing loss. We performed a study of the Alcoa Inc. audiometric database to evaluate the impact of this new rule. The 2003 rule increased the rate of potentially recordable hearing loss events from 0.2% to 1.6% per year. A total of 68.6% of potentially recordable cases had American Academy of Audiology/American Medical Association (AAO/AMA) hearing impairment at the time of recordability. On average, recordable loss occurred after onset of impairment, whereas the non-age-corrected 10-dB standard threshold shift (STS) usually preceded impairment. The OSHA Final Rule will significantly increase recordable cases of occupational hearing loss. The new case definition is usually accompanied by AAO/AMA hearing impairment. Other, more sensitive metrics should therefore be used for early detection and prevention of hearing loss. PMID:14665813

A Study of Relationship between the Acoustic Sensitivity of Vestibular System and the Ability to Trigger Sound-Evoked Muscle Reflex of the Middle Ear in Adults with Normal Hearing

Directory of Open Access Journals (Sweden)

S.F. Emami

2014-07-01

Full Text Available Introduction & Objective: The vestibular system is sound sensitive and the sensitivity is related to the saccule. The vestibular afferents are projected to the middle ear muscles (such as the stapedius. The goal of this research was studying the relationship between the vestibular hearing and the sound-evoked muscle reflex of the middle ear to 500 HZ. Materials & Methods: This study was a cross sectional-comparison done in audiology department of Sheikholreis C‍‍linic (Hamadan, Iran. The study groups consisted of thirty healthy people and thirty patients with benign paroxysmal positional vertigo. Inclusion criteria of the present study were to have normal hearing on pure tone audiometry, acoustic reflex, and speech discrimination scores. Based on ipsilateral acoustic reflex test at 500HZ, they were divided to normal and abnormal groups. Then they were evaluated by cervical vestibular evoked myogenic potentials (cVEMPs and finally classified in three groups (N Normal ear , (CVUA Contra lateral vertiginous ear with unaffected saccular sensitivity to sound,(IVA Ipsilateral vertiginous ear with affected saccular sensitivity to sound. Results: Thirty affected ears (IVA with decreased vestibular excitability as detected by ab-normal cVEMPs, revealed abnormal findings of acoustic reflex at 500HZ. Whereas, both un-affected (CVUA and normal ears (N had normal results. Multiple comparisons of mean values of cVEMPs (p13,n23 and acoustic reflex at500HZ among the three groups were sig-nificant. The correlation between acoustic reflex at 500HZ and p13 latencies was significant. The n23 latencies showed significant correlation with acoustic reflex at 500HZ. Conclusion: The vestibular sensitivity to sound retains the ability to trigger sound-evoked re-flex of the middle ear at 500 HZ. (Sci J Hamadan Univ Med Sci 2014; 21 (2:99-104

Characterizing auditory processing and perception in individual listeners with sensorineural hearing loss

DEFF Research Database (Denmark)

Jepsen, Morten Løve; Dau, Torsten

2011-01-01

–438 (2008)] was used as a framework. The parameters of the cochlear processing stage of the model were adjusted to account for behaviorally estimated individual basilar-membrane inputoutput functions and the audiogram, from which the amounts of inner hair-cell and outer hair-cell losses were estimated......This study considered consequences of sensorineural hearing loss in ten listeners. The characterization of individual hearing loss was based on psychoacoustic data addressing audiometric pure-tone sensitivity, cochlear compression, frequency selectivity, temporal resolution, and intensity...

Measurements on Hearing

DEFF Research Database (Denmark)

Poulsen, Torben

1996-01-01

Background material for measurements of hearing for grammar school pupils. The note gives the necessary background for the exercise 'Measurement on Hearing'. The topics comprise sound and decibel, the ear, basic psychoacoustics, hearing threshold, audiometric measurement methods, speech and speech...

Hearing Loss, Dizziness, and Carbohydrate Metabolism

OpenAIRE

Albernaz, Pedro L. Mangabeira

2015-01-01

Abstract Introduction Metabolic activity of the inner ear is very intense, and makes it sensitive to changes in the body homeostasis. This study involves a group of patients with inner ear disorders related to carbohydrate metabolism disturbances, including hearing loss, tinnitus, dizziness, and episodes of vertigo. Objectives To describe the symptoms of metabolic inner ear disorders and the examinations required to establish diagnoses. These symptoms are often the first to allow for an e...

Applications of direct-to-consumer hearing devices for adults with hearing loss: a review

Directory of Open Access Journals (Sweden)

Manchaiah V

2017-05-01

Full Text Available Vinaya Manchaiah,1–4 Brian Taylor,5 Ashley L Dockens,1 Nicole R Tran,1 Kayla Lane,1 Mariana Castle,1 Vibhu Grover1 1Department of Speech and Hearing Sciences, Lamar University, Beaumont, TX, USA; 2The Swedish Institute for Disability Research, Department of Behavioural Sciences and Learning, Linköping University, Linköping, Sweden; 3Audiology India, Mysore, 4Department of Speech and Hearing, School of Allied Health Sciences, Manipal University, Manipal, India; 5Taylor Audio LLC, Minneapolis, MN, USA Background: This systematic literature review is aimed at investigating applications of direct-to-consumer hearing devices for adults with hearing loss. This review discusses three categories of direct-to-consumer hearing devices: 1 personal sound amplification products (PSAPs, 2 direct-mail hearing aids, and 3 over-the-counter (OTC hearing aids.Method: A literature review was conducted using EBSCOhost and included the databases CINAHL, MEDLINE, and PsycINFO. After applying prior agreed inclusion and exclusion criteria, 13 reports were included in the review.Results: Included studies fell into three domains: 1 electroacoustic characteristics, 2 consumer surveys, and 3 outcome evaluations. Electroacoustic characteristics of these devices vary significantly with some meeting the stringent acoustic criteria used for hearing aids, while others producing dangerous output levels (ie, over 120-dB sound pressure level. Low-end (or low-cost devices were typically poor in acoustic quality and did not meet gain levels necessary for most adult and elderly hearing loss patterns (eg, presbycusis, especially in high frequencies. Despite direct-mail hearing aids and PSAPs being associated with lower satisfaction when compared to hearing aids purchased through hearing health care professionals, consumer surveys suggest that 5%–19% of people with hearing loss purchase hearing aids through direct-mail or online. Studies on outcome evaluation suggest positive

Relationship between hearing complaint and hearing loss among older people

Directory of Open Access Journals (Sweden)

Teixeira, Adriane Ribeiro

2009-03-01

Full Text Available Introduction: Presbycusis is a public health problem. Despite its high prevalence, many elders do not have their hearing ability investigated periodically, because they do not have a specific complaint. Objective: To check whether there is a relationship between the complaint and the presence of hearing loss in elder people. Method: Transversal study in elders from a neighborhood in the city of Canoas, Rio Grande do Sul. After the definition of the neighborhood's geographic boundaries, all houses were visited, the older people's addresses were ascertained and the invitations to take part in the research were provided. A questionnaire survey was applied which had a question about hearing loss complaint and air-conducted hearing thresholds were obtained and studied. Out of the 72 identified elders 50 elders agreed to participate, 35 (70% women, and 15 (30% men. Results: It was confirmed that only 12 (24% elders showed a specific complaint of hearing loss, although 33 (66% elders showed slight, moderate, severe and profound hearing losses. Conclusion: Data analysis confirmed there was no relationship between the complaint and the presence of hearing loss in the assessed group, and demonstrated the need to forward the elders for audiological evaluation even without any specific complaint.

Hearing devices for children with unilateral hearing loss: Patient- and parent-reported perspectives.

Science.gov (United States)

Purcell, Patricia L; Jones-Goodrich, Rose; Wisneski, Meghan; Edwards, Todd C; Sie, Kathleen C Y

2016-11-01

Management of children with unilateral hearing loss is not standardized. The primary goal of this study was to elicit patient- and parent-reported perspectives regarding usage of hearing devices in pediatric UHL and to suggest a basic algorithmic approach to management. Our tertiary care center recruited families of youth ages 5-19 years with unilateral hearing loss from January 2014 through October 2015. Parents of all youths completed a 36-item survey, and some youth ages 11-19 years participated in hour-long interviews. We assessed patterns of hearing device usage among participants, and performed qualitative data analysis to understand factors considered by youths when deciding whether or not to use a hearing device. Survey information was collected for 50 patients. Distribution of hearing loss severity in affected ear was mild 14%, moderate 26%, severe 22%, and profound 38%. The majority of children had sensorineural hearing loss (57%), followed by mixed (32%), and then conductive (11%). 34 children (68%) had tried a hearing device; 20 continued to use the device. Retention rates were similar among children with different degrees of hearing loss: mild 66%, moderate 50%, severe 60%, profound 64%. Sixteen children tried a wireless contralateral routing of signal (CROS) device, and 15 tried a behind-the-ear (BTE) hearing aid. Retention rates for CROS and BTE devices were 69% and 47%, respectively. The most common reason for cessation of use was discomfort, followed by lack of benefit. A majority of children with unilateral hearing loss who tried a hearing device continued to use it, and retention rates were similar across all degrees of hearing loss. These findings suggest that personal hearing devices should be included in management protocols. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Elderly With Different Types of Hearing Loss and Comorbidities: Satisfaction With Hearing Aids

Directory of Open Access Journals (Sweden)

Dashti

2015-07-01

Full Text Available Background Hearing loss is developing when age is rising. Initiation and progression rates of hearing loss vary among different individuals and groups. Objectives The current study aimed to determine satisfaction of the elderly with their hearing aids in different types of hearing loss and comorbidities. Patients and Methods The study was conducted on 40 elderly subjects suffering from hearing loss and using hearing aids. The data collection method included assessment of hearing loss in addition to using a questionnaire to estimate respondents' satisfaction with their hearing aids in daily life. The Persian version of the Satisfaction with Amplification in Daily Life (SADL questionnaire was administered. The data were analyzed using descriptive and inferential statistics by SPSS software version19. Results The mean satisfaction scores of the elderly were 4.83 ± 0.51 and 5.36 ± 0.30 in the sensorineural loss groups. There was no significant difference between different comorbidities. There was a significant difference between satisfaction level of cost and services subscales in the symmetrical styles of hearing loss (P value = 0.04. Conclusions The findings of the study indicated a high satisfaction of the elderly with their hearing aids, considering the type of hearing loss. Despite all the efforts to improve the audiologic services during verification process, the elderly should be consulted specifically in order to fit their hearing aid as well as their expectations from aid.

Quality of Life and Hearing Eight Years After Sudden Sensorineural Hearing Loss.

Science.gov (United States)

Härkönen, Kati; Kivekäs, Ilkka; Rautiainen, Markus; Kotti, Voitto; Vasama, Juha-Pekka

2017-04-01

To explore long-term hearing results, quality of life (QoL), quality of hearing (QoH), work-related stress, tinnitus, and balance problems after idiopathic sudden sensorineural hearing loss (ISSNHL). Cross-sectional study. We reviewed the audiograms of 680 patients with unilateral ISSNHL on average 8 years after the hearing impairment, and then divided the patients into two study groups based on whether their ISSNHL had recovered to normal (pure tone average [PTA] ≤ 30 dB) or not (PTA > 30 dB). The inclusion criteria were a hearing threshold decrease of 30 dB or more in at least three contiguous frequencies occurring within 72 hours in the affected ear and normal hearing in the contralateral ear. Audiograms of 217 patients fulfilled the criteria. We reviewed their medical records; measured present QoL, QoH, and work-related stress with specific questionnaires; and updated the hearing status. Poor hearing outcome after ISSNHL was correlated with age, severity of hearing loss, and vertigo together with ISSNHL. Quality of life and QoH were statistically significantly better in patients with recovered hearing, and the patients had statistically significantly less tinnitus and balance problems. During the 8-year follow-up, the PTA of the affected ear deteriorated on average 7 dB, and healthy ear deteriorated 6 dB. Idiopathic sudden sensorineural hearing loss that failed to recover had a negative impact on long-term QoL and QoH. The hearing deteriorated as a function of age similarly both in the affected and the healthy ear, and there were no differences between the groups. The cumulative recurrence rate for ISSNHL was 3.5%. 4 Laryngoscope, 127:927-931, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

What factors influence help-seeking for hearing impairment and hearing aid adoption in older adults?

Science.gov (United States)

Meyer, Carly; Hickson, Louise

2012-02-01

The purpose of this review paper was to identify factors that influence older adults' decisions to seek help for hearing impairment and to adopt hearing aids. A literature search of abstracts within peer-reviewed journal articles published in English between 1990 and 2010 was conducted in online bibliographic databases using the keywords: hearing; impair* or loss; seek* or candidate* or applicant* or acquir*; and hearing aid* or help or advice. Twenty-two articles that were directly relevant to this topic were included in this review. The evidence suggests that individuals are more likely to seek help for hearing impairment and/or adopt hearing aids if they: (1) have a moderate to severe hearing impairment and self-reported hearing-related activity limitations or participation restrictions; (2) are older; (3) perceive their hearing as poor; (4) consider there to be more benefits than barriers to amplification; and (5) perceive their significant other/s as supportive of hearing rehabilitation. A barrier to help-seeking for hearing impairment and hearing aid adoption appears to be general practitioners' management of age-related hearing impairment.

Hearing Aids Communication

DEFF Research Database (Denmark)

Globally, hearing loss is the second most frequent disability. About 80% of the persons affected by hearing loss do not use hearing aids. The goal of this edited volume is to present a theoretically founded, interdisciplinary approach geared at understanding and improving social interaction...

Specialization for underwater hearing by the tympanic middle ear of the turtle, Trachemys scripta elegans

DEFF Research Database (Denmark)

Christensen-Dalsgaard, J.; Brandt, Christian; Willis, K. L.

2012-01-01

Turtles, like other amphibious animals, face a trade-off between terrestrial and aquatic hearing. We used laser vibrometry and auditory brainstem responses to measure their sensitivity to vibration stimuli and to airborne versus underwater sound. Turtles are most sensitive to sound underwater, an...

Sensorineural and conductive hearing loss in infants diagnosed in the program of universal newborn hearing screening.

Science.gov (United States)

Wroblewska-Seniuk, Katarzyna; Dabrowski, Piotr; Greczka, Grazyna; Szabatowska, Katarzyna; Glowacka, Agata; Szyfter, Witold; Mazela, Jan

2018-02-01

The aim of this study was to analyze infants diagnosed with sensorineural or conductive hearing deficit and to identify risk factors associated with these defects. A retrospective analysis of infants diagnosed with hearing deficit based on the database of the universal newborn hearing screening program and medical records of the patients. 27 935 infants were covered by the universal neonatal hearing screening program. 109 (0.39%) were diagnosed with hearing deficit and referred for treatment and rehabilitation. 56 (51.4%) children were diagnosed with conductive, 38 (34.9%) with sensorineural and 15 (13.8%) with mixed type of hearing deficit. Children with sensorineural hearing deficit more frequently suffered from hyperbilirubinemia (p conductive hearing loss were more frequently diagnosed with isolated craniofacial anomalies (p hearing deficit occurred almost 3 times more often bilaterally than unilaterally (p hearing deficit, the difference was not significant. In children with conductive and mixed type of hearing loss the impairment was mainly mild while among those with sensorineural hearing deficit in almost 45% it was severe and profound (p hearing screening test by means of otoacoustic emissions and the final diagnosis of hearing deficit we found that the highest agreement rate was observed in children with sensorineural hearing loss (p hearing deficit was similar in children with sensorineural, conductive and mixed type of hearing loss, only hyperbilirubinemia seemed to predispose to sensorineural hearing deficit and isolated craniofacial malformations seemed to be associated with conductive hearing loss. Sensorineural hearing deficit usually occurred bilaterally and was severe or profound, while conductive and mixed type of hearing deficit were most often of mild degree. Most children with the final diagnosis of sensorineural hearing deficit had positive result of hearing screening by means of otoacoustic emissions. Copyright © 2017 Elsevier B.V. All

Memory for faces and objects by deaf and hearing signers and hearing nonsigners.

Science.gov (United States)

Arnold, P; Murray, C

1998-07-01

The memory of 11 deaf and 11 hearing British Sign Language users and 11 hearing nonsigners for pictures of faces of and verbalizable objects was measured using the game Concentration. The three groups performed at the same level for the objects. In contrast the deaf signers were better for faces than the hearing signers, who in turn were superior to the hearing nonsigners, who were the worst. Three hypotheses were made: That there would be no significant difference in terms of the number of attempts between the three groups on the verbalizable object task, that the hearing and deaf signers would demonstrate superior performance to that of the hearing nonsigners on the matching faces task, and that the hearing and deaf signers would exhibit similar performance levels on the matching faces task. The first two hypotheses were supported, but the third was not. Deaf signers were found to be superior for memory for faces to hearing signers and hearing nonsigners. Possible explanations for the findings are discussed, including the possibility that deafness and the long use of sign language have additive effects.

Comparison of general health status in mothers of hearing and hearing-impaired children

Directory of Open Access Journals (Sweden)

Movallali

2013-05-01

Full Text Available Background and Aim: The birth of a hearing-impaired child and raising him/her often brings special psychological feelings for parents, especially mothers who spend more time with the child. This study aimed to compare the general health status in mothers of hearing-impaired and hearing children. Methods: This was a descriptive-analytic study. General Health Questionnaire was used to identify general health status; and data were analyzed with independent-t test. Results: The general health level of mothers of hearing-impaired children was lower than mothers of normal hearing children (p=0.01 . The average scores of anxiety (p=0.01, depression (p= 0.01 and physical (p=0.02 symptoms and social function (p=0.01 of mothers of hearing-impaired children was higher than mothers of normal hearing ones (p=0.01. Conclusion: Having a child with hearing impairment affects mothers’ general health status. Our findings show that it’s necessary to provide psychological and social support for mothers of hearing-impaired children.

Low empathy in deaf and hard of hearing (pre)adolescents compared to normal hearing controls.

Science.gov (United States)

Netten, Anouk P; Rieffe, Carolien; Theunissen, Stephanie C P M; Soede, Wim; Dirks, Evelien; Briaire, Jeroen J; Frijns, Johan H M

2015-01-01

The purpose of this study was to examine the level of empathy in deaf and hard of hearing (pre)adolescents compared to normal hearing controls and to define the influence of language and various hearing loss characteristics on the development of empathy. The study group (mean age 11.9 years) consisted of 122 deaf and hard of hearing children (52 children with cochlear implants and 70 children with conventional hearing aids) and 162 normal hearing children. The two groups were compared using self-reports, a parent-report and observation tasks to rate the children's level of empathy, their attendance to others' emotions, emotion recognition, and supportive behavior. Deaf and hard of hearing children reported lower levels of cognitive empathy and prosocial motivation than normal hearing children, regardless of their type of hearing device. The level of emotion recognition was equal in both groups. During observations, deaf and hard of hearing children showed more attention to the emotion evoking events but less supportive behavior compared to their normal hearing peers. Deaf and hard of hearing children attending mainstream education or using oral language show higher levels of cognitive empathy and prosocial motivation than deaf and hard of hearing children who use sign (supported) language or attend special education. However, they are still outperformed by normal hearing children. Deaf and hard of hearing children, especially those in special education, show lower levels of empathy than normal hearing children, which can have consequences for initiating and maintaining relationships.

Sensorineural Hearing Loss Associated with Occupational Noise Exposure: Effects of Age-Corrections

Directory of Open Access Journals (Sweden)

2009-02-01

Full Text Available Noise-induced permanent threshold shifts (NIPTS were computed from retrospective audiometric analyses by subtracting aging effects on hearing sensitivity in sixty-eight patients with bilateral sensorineural hearing loss who reported significant occupational noise exposure histories. There were significant effects of age on NIPTS but no significant gender- or ear- differences in terms of NIPTS. The NIPTS at 2,000 Hz was found to be significantly greater than NIPTS at frequencies 500 Hz, 1,000 Hz, 4,000 Hz, and 8,000 Hz. Defined noise notches were seen in the audiograms of 38/136 (27% ears with SNHL. Results support models that suggest interactive effects of aging and noise on sensorineural hearing loss in ears with occupational noise exposure.

Comparative analysis of endurance of not hearing and hearing students

Directory of Open Access Journals (Sweden)

Iwańska Dagmara

2013-11-01

Full Text Available Study aim: Sport participation is important for deaf children, as participants experience physical, psychological and social benefits [23]. This study is a summary of four year’s researches on the endurance level of deaf and well hearing girls and boys. The aim of this study was to compare endurance of not hearing and hearing students.

[Presbycusis - Age Related Hearing Loss].

Science.gov (United States)

Fischer, N; Weber, B; Riechelmann, H

2016-07-01

Presbycusis or age related hearing loss can be defined as a progressive, bilateral and symmetrical sensorineural hearing loss due to age related degeneration of inner ear structures. It can be considered a multifactorial complex disorder with environmental and genetic factors. The molecular, electrophysiological and histological damage at different levels of the inner ear cause a progressive hearing loss, which usually affects the high frequencies of hearing. The resulting poor speech recognition has a negative impact on cognitive, emotional and social function in older adults. Recent investigations revealed an association between hearing impairment and social isolation, anxiety, depression and cognitive decline in elderly. These findings emphasize the importance of diagnosis and treating hearing loss in the elderly population. Hearing aids are the most commonly used devices for treating presbycusis. The technical progress of implantable hearing devices allows an effective hearing rehabilitation even in elderly with severe hearing loss. However, most people with hearing impairments are not treated adequately. © Georg Thieme Verlag KG Stuttgart · New York.

Identification of induced and naturally occurring conductive hearing loss in mice using bone conduction.

Science.gov (United States)

Chhan, David; McKinnon, Melissa L; Rosowski, John J

2017-03-01

While many mouse models of hearing loss have been described, a significant fraction of the genetic defects in these models affect both the inner ear and middle ears. A common method used to separate inner-ear (sensory-neural) from middle-ear (conductive) pathologies in the hearing clinic is the combination of air-conduction and bone-conduction audiometry. In this report, we investigate the use of air- and bone-conducted evoked auditory brainstem responses to perform a similar separation in mice. We describe a technique by which we stimulate the mouse ear both acoustically and via whole-head vibration. We investigate the sensitivity of this technique to conductive hearing loss by introducing middle-ear lesions in normal hearing mice. We also use the technique to investigate the presence of an age-related conductive hearing loss in a common mouse model of presbycusis, the BALB/c mouse. Copyright © 2017 Elsevier B.V. All rights reserved.

Hearing Screening and Diagnostic Evaluation of Children With Unilateral and Mild Bilateral Hearing Loss

OpenAIRE

Ross, Danielle S.; Holstrum, W. June; Gaffney, Marcus; Green, Denise; Oyler, Robert F.; Gravel, Judith S.

2008-01-01

More than 90% of newborns in the United States are now being screened for hearing loss. A large fraction of cases of unilateral hearing loss and mild bilateral hearing loss are not currently identified through newborn hearing screening. This is of concern because a preponderance of research has demonstrated that unilateral hearing loss and mild bilateral hearing loss can lead to developmental delays and educational problems for some children. To help address this probable underidentification ...

Noise induced hearing loss and other hearing complaints among musicians of symphony orchestras

NARCIS (Netherlands)

Jansen, E. J. M.; Helleman, H. W.; Dreschler, W. A.; de Laat, J. A. P. M.

2009-01-01

OBJECTIVES: An investigation of the hearing status of musicians of professional symphony orchestras. Main questions are: (1) Should musicians be treated as a special group with regard to hearing, noise, and noise related hearing problems (2) Do patterns of hearing damage differ for different

Hearing Aid and children

Directory of Open Access Journals (Sweden)

Jamileh Fatahi

2002-07-01

Full Text Available In order to develop oral communication, hearing impaired infants and young children must be able to hear speech comfortably and consistently. To day children with all degrees of hearing loss may be condidates for some kinds of amlification. As children differ from adults, many Factors should be consider in hearing aid selection, evaluation and fitting. For example the child age when he or she is candidate for custom instruments? Do we consider programmable Hearing aid? Are multi memory instruments appropriate for them? What about directional microphones? What style of hearing aid do we select? In this paper such questions are Answered.

Low Empathy in Deaf and Hard of Hearing (Pre)Adolescents Compared to Normal Hearing Controls

Science.gov (United States)

Netten, Anouk P.; Rieffe, Carolien; Theunissen, Stephanie C. P. M.; Soede, Wim; Dirks, Evelien; Briaire, Jeroen J.; Frijns, Johan H. M.

2015-01-01

Objective The purpose of this study was to examine the level of empathy in deaf and hard of hearing (pre)adolescents compared to normal hearing controls and to define the influence of language and various hearing loss characteristics on the development of empathy. Methods The study group (mean age 11.9 years) consisted of 122 deaf and hard of hearing children (52 children with cochlear implants and 70 children with conventional hearing aids) and 162 normal hearing children. The two groups were compared using self-reports, a parent-report and observation tasks to rate the children’s level of empathy, their attendance to others’ emotions, emotion recognition, and supportive behavior. Results Deaf and hard of hearing children reported lower levels of cognitive empathy and prosocial motivation than normal hearing children, regardless of their type of hearing device. The level of emotion recognition was equal in both groups. During observations, deaf and hard of hearing children showed more attention to the emotion evoking events but less supportive behavior compared to their normal hearing peers. Deaf and hard of hearing children attending mainstream education or using oral language show higher levels of cognitive empathy and prosocial motivation than deaf and hard of hearing children who use sign (supported) language or attend special education. However, they are still outperformed by normal hearing children. Conclusions Deaf and hard of hearing children, especially those in special education, show lower levels of empathy than normal hearing children, which can have consequences for initiating and maintaining relationships. PMID:25906365

Music and hearing aids.

Science.gov (United States)

Madsen, Sara M K; Moore, Brian C J

2014-10-31

The signal processing and fitting methods used for hearing aids have mainly been designed to optimize the intelligibility of speech. Little attention has been paid to the effectiveness of hearing aids for listening to music. Perhaps as a consequence, many hearing-aid users complain that they are not satisfied with their hearing aids when listening to music. This issue inspired the Internet-based survey presented here. The survey was designed to identify the nature and prevalence of problems associated with listening to live and reproduced music with hearing aids. Responses from 523 hearing-aid users to 21 multiple-choice questions are presented and analyzed, and the relationships between responses to questions regarding music and questions concerned with information about the respondents, their hearing aids, and their hearing loss are described. Large proportions of the respondents reported that they found their hearing aids to be helpful for listening to both live and reproduced music, although less so for the former. The survey also identified problems such as distortion, acoustic feedback, insufficient or excessive gain, unbalanced frequency response, and reduced tone quality. The results indicate that the enjoyment of listening to music with hearing aids could be improved by an increase of the input and output dynamic range, extension of the low-frequency response, and improvement of feedback cancellation and automatic gain control systems. © The Author(s) 2014.

Music and Hearing Aids

Directory of Open Access Journals (Sweden)

Sara M. K. Madsen

2014-10-01

Full Text Available The signal processing and fitting methods used for hearing aids have mainly been designed to optimize the intelligibility of speech. Little attention has been paid to the effectiveness of hearing aids for listening to music. Perhaps as a consequence, many hearing-aid users complain that they are not satisfied with their hearing aids when listening to music. This issue inspired the Internet-based survey presented here. The survey was designed to identify the nature and prevalence of problems associated with listening to live and reproduced music with hearing aids. Responses from 523 hearing-aid users to 21 multiple-choice questions are presented and analyzed, and the relationships between responses to questions regarding music and questions concerned with information about the respondents, their hearing aids, and their hearing loss are described. Large proportions of the respondents reported that they found their hearing aids to be helpful for listening to both live and reproduced music, although less so for the former. The survey also identified problems such as distortion, acoustic feedback, insufficient or excessive gain, unbalanced frequency response, and reduced tone quality. The results indicate that the enjoyment of listening to music with hearing aids could be improved by an increase of the input and output dynamic range, extension of the low-frequency response, and improvement of feedback cancellation and automatic gain control systems.

Unexpected skeletal histology of an ichthyosaur from the Middle Jurassic of Patagonia: implications for evolution of bone microstructure among secondary aquatic tetrapods

Science.gov (United States)

Talevi, Marianella; Fernández, Marta S.

2012-03-01

During the Mesozoic, one of the most significant evolutionary processes was the secondary adaptation of tetrapods to life in water. Several non-related lineages invaded from the terrestrial realms and from the oceans of the entire world. Among these lineages, ichthyosaurs were particularly successful. Advance parvipelvian ichthyosaurs were the first tetrapods to evolve a fish-shaped body profile. The deep skeletal modifications of their bodies, as well as their biology, depict advance ichthyosaurs as the paradigm of secondary adaptation of reptiles to marine life. Functional inferences point to them as off-shore cruising forms, similar to a living tuna, and some of them were capable of deep diving. Bone histology of some genera such as Temnodontosaurus, Stenopterygius, Ichthyosaurus, and Caypullisaurus, characterized by overall cancellous bone, is consistent with the idea of a fish-shaped ichthyosaurs as fast and far cruisers. Here, we provide histological examination of the ribs of the Middle Jurassic parvipelvian Mollesaurus. Contrasting with the bone histology of other parvipelvian, Mollesaurus ribs are characterized by a compact and thick cortex. Our data indicate that the rib cage was heavy and suggest that not all advanced ichthyosaurs were fast cruisers. The compact and dense ribs in these parvipelvian show that advance ichthyosaurs were ecologically more diverse than previously thought and that the lightening of the skeleton reversed, as also occurred in the evolution of cetacean, at least once along the evolutionary history of ichthyosaurs.

Auditory Outcomes with Hearing Rehabilitation in Children with Unilateral Hearing Loss: A Systematic Review.

Science.gov (United States)

Appachi, Swathi; Specht, Jessica L; Raol, Nikhila; Lieu, Judith E C; Cohen, Michael S; Dedhia, Kavita; Anne, Samantha

2017-10-01

Objective Options for management of unilateral hearing loss (UHL) in children include conventional hearing aids, bone-conduction hearing devices, contralateral routing of signal (CROS) aids, and frequency-modulating (FM) systems. The objective of this study was to systematically review the current literature to characterize auditory outcomes of hearing rehabilitation options in UHL. Data Sources PubMed, EMBASE, Medline, CINAHL, and Cochrane Library were searched from inception to January 2016. Manual searches of bibliographies were also performed. Review Methods Studies analyzing auditory outcomes of hearing amplification in children with UHL were included. Outcome measures included functional and objective auditory results. Two independent reviewers evaluated each abstract and article. Results Of the 249 articles identified, 12 met inclusion criteria. Seven articles solely focused on outcomes with bone-conduction hearing devices. Outcomes favored improved pure-tone averages, speech recognition thresholds, and sound localization in implanted patients. Five studies focused on FM systems, conventional hearing aids, or CROS hearing aids. Limited data are available but suggest a trend toward improvement in speech perception with hearing aids. FM systems were shown to have the most benefit for speech recognition in noise. Studies evaluating CROS hearing aids demonstrated variable outcomes. Conclusions Data evaluating functional and objective auditory measures following hearing amplification in children with UHL are limited. Most studies do suggest improvement in speech perception, speech recognition in noise, and sound localization with a hearing rehabilitation device.

Hearing Aids

Science.gov (United States)

... primarily useful in improving the hearing and speech comprehension of people who have hearing loss that results ... and you can change the program for different listening environments—from a small, quiet room to a ...

Triagem auditiva neonatal com emissões otoacusticas e reflexo cocleo-palpebral: estudo da sensibilidade e especificidade Newborn Hearing Screening with otoacoustic emissions and cochlear-palpebral reflex: sensitivity and specificity study

Directory of Open Access Journals (Sweden)

Rosanna Mariangela Giaffredo Angrisani

2012-10-01

Full Text Available OBJETIVO: analisar a especificidade e sensibilidade da TAN com emissões otoacústicas evocadas por estimulo transiente (EOAT associadas à pesquisa do reflexo cócleo-palpebral (RCP, comparando-os aos resultados do Potencial Evocado Auditivo de Tronco Encefalico (PEATE. MÉTODO: a casuística do presente estudo foi composta por 369 RN de risco para deficiência auditiva que foram submetidos à triagem com a captação das emissões otoacústicas evocadas por estímulo transiente e pesquisa do reflexo cócleo- palpebral. Os resultados foram comparados aos resultados do Potencial Evocado Auditivo de Tronco Encefalico (PEATE. RESULTADOS: a incidência do tipo da perda auditiva na população geral foi de 4RN (1,1% com perda coclear, 22 (5,9% com perda condutiva, 2 (0,5% com espectro da neuropatia auditiva (ENA, 14 (3,8% com alteração central e 15 (4,1% com atraso de maturação da via auditiva. A TAN mostrou 100% de sensibilidade e 94,6% de especificidade na detecção de alterações cocleares e espectro da neuropatia auditiva; 77,3% de sensibilidade e 94,6% de especificidade na detecção de alterações condutivas e 42,9% de sensibilidade e 94,6% de especificidade na detecção de alterações centrais. Todos os achados evidenciaram diferenças estatisticamente significantes em relação aos neonatos auditivamente normais. CONCLUSÃO: este protocolo de TAN mostrou-se eficaz na detecção de RN com alterações de cocleares e espectro da neuropatia auditiva com sensibilidade e especificidade elevadas.PURPOSE: to study the specificity and sensitivity of NHS with otoacoustic emissions transient stimulus (TEOAE associated with cochlear-palpebral reflex (CPR, and comparing the results of Auditory Evoked Potential (BAEP. METHOD: three hundred and sixty-nine neonates under risk of hearing loss were evaluated. Evaluation procedures consisted of transient otocoustic emissions(TOAEs, cochlear-palpebral reflex (CPR, and ABR diagnostic carried out in the

Applications of direct-to-consumer hearing devices for adults with hearing loss: a review

Science.gov (United States)

Manchaiah, Vinaya; Taylor, Brian; Dockens, Ashley L; Tran, Nicole R; Lane, Kayla; Castle, Mariana; Grover, Vibhu

2017-01-01

Background This systematic literature review is aimed at investigating applications of direct-to-consumer hearing devices for adults with hearing loss. This review discusses three categories of direct-to-consumer hearing devices: 1) personal sound amplification products (PSAPs), 2) direct-mail hearing aids, and 3) over-the-counter (OTC) hearing aids. Method A literature review was conducted using EBSCOhost and included the databases CINAHL, MEDLINE, and PsycINFO. After applying prior agreed inclusion and exclusion criteria, 13 reports were included in the review. Results Included studies fell into three domains: 1) electroacoustic characteristics, 2) consumer surveys, and 3) outcome evaluations. Electroacoustic characteristics of these devices vary significantly with some meeting the stringent acoustic criteria used for hearing aids, while others producing dangerous output levels (ie, over 120-dB sound pressure level). Low-end (or low-cost) devices were typically poor in acoustic quality and did not meet gain levels necessary for most adult and elderly hearing loss patterns (eg, presbycusis), especially in high frequencies. Despite direct-mail hearing aids and PSAPs being associated with lower satisfaction when compared to hearing aids purchased through hearing health care professionals, consumer surveys suggest that 5%–19% of people with hearing loss purchase hearing aids through direct-mail or online. Studies on outcome evaluation suggest positive outcomes of OTC devices in the elderly population. Of note, OTC outcomes appear better when a hearing health care professional supports these users. Conclusion While some direct-to-consumer hearing devices have the capability to produce adverse effects due to production of dangerously high sound levels and internal noise, the existing literature suggests that there are potential benefits of these devices. Research of direct-to-consumer hearing devices is limited, and current published studies are of weak quality. Much

Hearing in cetaceans: from natural history to experimental biology.

Science.gov (United States)

Mooney, T Aran; Yamato, Maya; Branstetter, Brian K

2012-01-01

Sound is a primary sensory cue for most marine mammals, and this is especially true for cetaceans. To passively and actively acquire information about their environment, cetaceans have some of the most derived ears of all mammals, capable of sophisticated, sensitive hearing and auditory processing. These capabilities have developed for survival in an underwater world where sound travels five times faster than in air, and where light is quickly attenuated and often limited at depth, at night, and in murky waters. Cetacean auditory evolution has capitalized on the ubiquity of sound cues and the efficiency of underwater acoustic communication. The sense of hearing is central to cetacean sensory ecology, enabling vital behaviours such as locating prey, detecting predators, identifying conspecifics, and navigating. Increasing levels of anthropogenic ocean noise appears to influence many of these activities. Here, we describe the historical progress of investigations on cetacean hearing, with a particular focus on odontocetes and recent advancements. While this broad topic has been studied for several centuries, new technologies in the past two decades have been leveraged to improve our understanding of a wide range of taxa, including some of the most elusive species. This chapter addresses topics including how sounds are received, what sounds are detected, hearing mechanisms for complex acoustic scenes, recent anatomical and physiological studies, the potential impacts of noise, and mysticete hearing. We conclude by identifying emerging research topics and areas which require greater focus. Copyright © 2012 Elsevier Ltd. All rights reserved.

Hearing in the sea otter (Enhydra lutris): auditory profiles for an amphibious marine carnivore.

Science.gov (United States)

Ghoul, Asila; Reichmuth, Colleen

2014-11-01

In this study we examine the auditory capabilities of the sea otter (Enhydra lutris), an amphibious marine mammal that remains virtually unstudied with respect to its sensory biology. We trained an adult male sea otter to perform a psychophysical task in an acoustic chamber and at an underwater apparatus. Aerial and underwater audiograms were constructed from detection thresholds for narrowband signals measured in quiet conditions at frequencies from 0.125-40 kHz. Aerial hearing thresholds were also measured in the presence of octave-band masking noise centered at eight signal frequencies (0.25-22.6 kHz) so that critical ratios could be determined. The aerial audiogram of the sea otter resembled that of sea lions and showed a reduction in low-frequency sensitivity relative to terrestrial mustelids. Best sensitivity was -1 dB re 20 µPa at 8 kHz. Under water, hearing sensitivity was significantly reduced when compared to sea lions and other pinniped species, demonstrating that sea otter hearing is primarily adapted to receive airborne sounds. Critical ratios were more than 10 dB higher than those measured for pinnipeds, suggesting that sea otters are less efficient than other marine carnivores at extracting acoustic signals from background noise, especially at frequencies below 2 kHz.

Pure-tone audiograms and hearing loss in the white whale (Delphinapterus leucas)

Science.gov (United States)

Finneran, James J.; Carder, Donald A.; Dear, Randall; Belting, Traci; Ridgway, Sam H.

2003-10-01

A behavioral response paradigm was used to measure pure-tone audiograms for two white whales (Delphinapterus leucas). Tests were conducted over a 20 month period at the Point Defiance Zoo and Aquarium, in Tacoma, Washington. Subjects consisted of two males, aged 8-10 and 9-11 during the course of the study. Subjects were born in an oceanarium and had been housed together for all of their lives. Hearing thresholds were measured using a modified up/down staircase procedure and acoustic response paradigm where subjects were trained to whistle in response to hearing test tones and to remain quiet otherwise. Test frequencies ranged from approximately 2 to 130 kHz. Best sensitivities ranged from 40 to 50 dB re: 1 Pa. Both subjects had traditional U-shaped mammalian audiograms; however, one subject exhibited significant high-frequency hearing loss, above approximately 37 kHz. The experimental setup and procedure will be presented and the measured hearing thresholds compared to those previously measured in white whales. The potential role of ototoxic antibiotics in the observed hearing loss will be discussed. [Work supported by ONR Marine Mammal S&T Program and the U.S. Navy CNO(N45).

Prediction of hearing outcomes by multiple regression analysis in patients with idiopathic sudden sensorineural hearing loss.

Science.gov (United States)

Suzuki, Hideaki; Tabata, Takahisa; Koizumi, Hiroki; Hohchi, Nobusuke; Takeuchi, Shoko; Kitamura, Takuro; Fujino, Yoshihisa; Ohbuchi, Toyoaki

2014-12-01

This study aimed to create a multiple regression model for predicting hearing outcomes of idiopathic sudden sensorineural hearing loss (ISSNHL). The participants were 205 consecutive patients (205 ears) with ISSNHL (hearing level ≥ 40 dB, interval between onset and treatment ≤ 30 days). They received systemic steroid administration combined with intratympanic steroid injection. Data were examined by simple and multiple regression analyses. Three hearing indices (percentage hearing improvement, hearing gain, and posttreatment hearing level [HLpost]) and 7 prognostic factors (age, days from onset to treatment, initial hearing level, initial hearing level at low frequencies, initial hearing level at high frequencies, presence of vertigo, and contralateral hearing level) were included in the multiple regression analysis as dependent and explanatory variables, respectively. In the simple regression analysis, the percentage hearing improvement, hearing gain, and HLpost showed significant correlation with 2, 5, and 6 of the 7 prognostic factors, respectively. The multiple correlation coefficients were 0.396, 0.503, and 0.714 for the percentage hearing improvement, hearing gain, and HLpost, respectively. Predicted values of HLpost calculated by the multiple regression equation were reliable with 70% probability with a 40-dB-width prediction interval. Prediction of HLpost by the multiple regression model may be useful to estimate the hearing prognosis of ISSNHL. © The Author(s) 2014.

Revisiting the relationship of three-dimensional fluid attenuation inversion recovery imaging and hearing outcomes in adults with idiopathic unilateral sudden sensorineural hearing loss

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Liao, Wen-Huei [School of Medicine, National Yang Ming University, Taipei, 11221, Taiwan (China); Department of Otolaryngology, Taipei Veterans General Hospital, Taipei, 11217, Taiwan (China); Wu, Hsiu-Mei [School of Medicine, National Yang Ming University, Taipei, 11221, Taiwan (China); Department of Radiology, Taipei Veterans General Hospital, Taipei, 11217, Taiwan (China); Wu, Hung-Yi [Department of Radiology, Taipei Veterans General Hospital, Taipei, 11217, Taiwan (China); Tu, Tzong-Yang; Shiao, An-Suey [School of Medicine, National Yang Ming University, Taipei, 11221, Taiwan (China); Department of Otolaryngology, Taipei Veterans General Hospital, Taipei, 11217, Taiwan (China); Castillo, Mauricio [Department of Radiology, University of North Carolina, Chapel Hill, NC, 27599-7510 (United States); Hung, Sheng-Che, E-mail: hsz829@gmail.com [School of Medicine, National Yang Ming University, Taipei, 11221, Taiwan (China); Department of Radiology, Taipei Veterans General Hospital, Taipei, 11217, Taiwan (China); Department of Biomedical Imaging and Radiological Sciences, National Yang Ming University, Taipei, 11221, Taiwan (China)

2016-12-15

Background and purpose: Three-dimensional fluid attenuation inversion recovery (3D FLAIR) may demonstrate high signal in the inner ears of patients with idiopathic sudden sensorineural hearing loss (ISSNHL), but the correlations of this finding with outcomes are still controversial. Here we compared 4 3D MRI sequences with the outcomes of patients with ISSNHL. Materials and methods: 77 adult patients with ISSNHL underwent MRI with pre contrast FLAIR, fast imaging employing steady-state acquisition images (FIESTA-C), post contrast T1WI and post contrast FLAIR. The extent and degree of high signal in both cochleas were evaluated in all patients, and asymmetry ratios between the affected ears and the normal ones were calculated. The relationships among MRI findings, including extent and asymmetry of abnormal cochlear high signals, degree of FLAIR enhancement, and clinical information, including age, vestibular symptoms, baseline hearing loss, and final hearing outcomes were analyzed. Results: 54 patients (28 men; age, 52.1 ± 15.5 years) were included in our study. Asymmetric cochlear signal intensities were more frequently observed in pre contrast and post contrast FLAIR (79.6% and 68.5%) than in FIESTA-C (61.1%) and T1WI (51.9%) (p < 0.001). Age, baseline hearing loss, extent of high signal and asymmetry ratios of pre contrast and post contrast FLAIR were all correlated with final hearing outcomes. In multivariate analysis, age and the extent of high signals were the most significant predictors of final hearing outcomes. Conclusion: 3D FLAIR provides a higher sensitivity in detecting the asymmetric cochlear signal abnormality. The more asymmetric FLAIR signals and presence of high signals beyond cochlea indicated a poorer prognosis.

Early Hearing Detection and Intervention: Can Your Baby Hear?

Centers for Disease Control (CDC) Podcasts

2007-06-15

This podcast discusses how important it is that every child receives a hearing screening as soon as possible after birth. It also gives specific ways that parents and health providers can find out if a child has a possible hearing loss and where to get further information. (Created 6/5/2007 by the Early Hearing Detection and Intervention Program, NCBDDD).  Created: 6/15/2007 by National Center on Birth Defects and Developmental Disabilities.   Date Released: 6/25/2007.

45 CFR 99.11 - Notice of hearing or opportunity for hearing.

Science.gov (United States)

2010-10-01

... 45 Public Welfare 1 2010-10-01 2010-10-01 false Notice of hearing or opportunity for hearing. 99.11 Section 99.11 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION PROCEDURE FOR HEARINGS FOR THE CHILD CARE AND DEVELOPMENT FUND Preliminary Matters-Notice and Parties § 99...

49 CFR 209.115 - Hearing.

Science.gov (United States)

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Hearing. 209.115 Section 209.115 Transportation... Hearing. (a) When a hearing is requested and scheduled under § 209.113, a hearing officer designated by the Chief Counsel convenes and presides over the hearing. If requested by respondent and if...

Motivation to Address Self-Reported Hearing Problems in Adults with Normal Hearing Thresholds

Science.gov (United States)

Alicea, Carly C. M.; Doherty, Karen A.

2017-01-01

Purpose: The purpose of this study was to compare the motivation to change in relation to hearing problems in adults with normal hearing thresholds but who report hearing problems and that of adults with a mild-to-moderate sensorineural hearing loss. Factors related to their motivation were also assessed. Method: The motivation to change in…

Postural control assessment in students with normal hearing and sensorineural hearing loss.

Science.gov (United States)

Melo, Renato de Souza; Lemos, Andrea; Macky, Carla Fabiana da Silva Toscano; Raposo, Maria Cristina Falcão; Ferraz, Karla Mônica

2015-01-01

Children with sensorineural hearing loss can present with instabilities in postural control, possibly as a consequence of hypoactivity of their vestibular system due to internal ear injury. To assess postural control stability in students with normal hearing (i.e., listeners) and with sensorineural hearing loss, and to compare data between groups, considering gender and age. This cross-sectional study evaluated the postural control of 96 students, 48 listeners and 48 with sensorineural hearing loss, aged between 7 and 18 years, of both genders, through the Balance Error Scoring Systems scale. This tool assesses postural control in two sensory conditions: stable surface and unstable surface. For statistical data analysis between groups, the Wilcoxon test for paired samples was used. Students with hearing loss showed more instability in postural control than those with normal hearing, with significant differences between groups (stable surface, unstable surface) (ppostural control compared to normal hearing students of the same gender and age. Copyright © 2014 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

34 CFR 668.116 - Hearing.

Science.gov (United States)

2010-07-01

... 34 Education 3 2010-07-01 2010-07-01 false Hearing. 668.116 Section 668.116 Education Regulations... Program Review Determinations § 668.116 Hearing. (a) A hearing is a process conducted by the hearing official whereby an orderly presentation of arguments and evidence is made by the parties. (b) The hearing...

40 CFR 57.807 - Hearing.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 5 2010-07-01 2010-07-01 false Hearing. 57.807 Section 57.807... § 57.807 Hearing. (a) Composition of hearing panel. The Presiding Officer shall preside at the hearing held under this subpart. An EPA panel shall also take part in the hearing. In general, the membership...

34 CFR 668.88 - Hearing.

Science.gov (United States)

2010-07-01

... 34 Education 3 2010-07-01 2010-07-01 false Hearing. 668.88 Section 668.88 Education Regulations of... Proceedings § 668.88 Hearing. (a) A hearing is an orderly presentation of arguments and evidence conducted by a hearing official. (b) If the hearing official, the designated department official who brought a...

19 CFR 356.23 - Hearing.

Science.gov (United States)

2010-04-01

... 19 Customs Duties 3 2010-04-01 2010-04-01 false Hearing. 356.23 Section 356.23 Customs Duties... § 356.23 Hearing. (a) Scheduling of hearing. The administrative law judge will schedule the hearing at a... parties adequately to prepare for the hearing and the importance of expeditiously resolving the matter. (b...

Hearing aid-related satisfaction based on type and degree of hearing loss in elderly

Directory of Open Access Journals (Sweden)

Farzad FarajiKhiavi

2015-02-01

Full Text Available Background and Aim: Hearing loss is one of the most prevalent chronic diseases in the elderly; using a hearing aid to alleviate auditory impairment can positively affect their quality of life. This research aimed to determine the level of satisfaction concerning hearing aids in elderly people with hearing impairment based on the type and degree of hearing loss.Methods: An analytic cross-sectional research design was used ; the sample included 40 elderly people who used hearing aids. According to the World Health Organization (WHO age classification, participants were divided into two age groups: 65-74 years (n=20 and 75-90 years (n=20. Satisfaction levels were assessed using a standard satisfaction with amplification in daily life (SADL questionnaire.Results: Satisfaction levels in the 65-74 age group were significantly higher than that in the 75-90 age group (p=0.02. Participants with mixed hearing loss revealed higher satisfaction levels than participants with sensorineural hearing loss (p=0.02. On the negative effects dimension, participants with severe hearing loss exhibited significantly higher satisfaction levels than participants with moderate or moderate to severe hearing loss (p=0.01.Conclusion: Total satisfaction mean scores were relatively high in the elderly participants . Negative features could be reduced via careful consultation regarding the aids’ amplifying capabilities and limitations in groups with moderate or moderate to severe hearing loss.

Fin whale sound reception mechanisms: skull vibration enables low-frequency hearing.

Directory of Open Access Journals (Sweden)

Ted W Cranford

Full Text Available Hearing mechanisms in baleen whales (Mysticeti are essentially unknown but their vocalization frequencies overlap with anthropogenic sound sources. Synthetic audiograms were generated for a fin whale by applying finite element modeling tools to X-ray computed tomography (CT scans. We CT scanned the head of a small fin whale (Balaenoptera physalus in a scanner designed for solid-fuel rocket motors. Our computer (finite element modeling toolkit allowed us to visualize what occurs when sounds interact with the anatomic geometry of the whale's head. Simulations reveal two mechanisms that excite both bony ear complexes, (1 the skull-vibration enabled bone conduction mechanism and (2 a pressure mechanism transmitted through soft tissues. Bone conduction is the predominant mechanism. The mass density of the bony ear complexes and their firmly embedded attachments to the skull are universal across the Mysticeti, suggesting that sound reception mechanisms are similar in all baleen whales. Interactions between incident sound waves and the skull cause deformations that induce motion in each bony ear complex, resulting in best hearing sensitivity for low-frequency sounds. This predominant low-frequency sensitivity has significant implications for assessing mysticete exposure levels to anthropogenic sounds. The din of man-made ocean noise has increased steadily over the past half century. Our results provide valuable data for U.S. regulatory agencies and concerned large-scale industrial users of the ocean environment. This study transforms our understanding of baleen whale hearing and provides a means to predict auditory sensitivity across a broad spectrum of sound frequencies.

Improving speech-in-noise recognition for children with hearing loss: potential effects of language abilities, binaural summation, and head shadow.

Science.gov (United States)

Nittrouer, Susan; Caldwell-Tarr, Amanda; Tarr, Eric; Lowenstein, Joanna H; Rice, Caitlin; Moberly, Aaron C

2013-08-01

This study examined speech recognition in noise for children with hearing loss, compared it to recognition for children with normal hearing, and examined mechanisms that might explain variance in children's abilities to recognize speech in noise. Word recognition was measured in two levels of noise, both when the speech and noise were co-located in front and when the noise came separately from one side. Four mechanisms were examined as factors possibly explaining variance: vocabulary knowledge, sensitivity to phonological structure, binaural summation, and head shadow. Participants were 113 eight-year-old children. Forty-eight had normal hearing (NH) and 65 had hearing loss: 18 with hearing aids (HAs), 19 with one cochlear implant (CI), and 28 with two CIs. Phonological sensitivity explained a significant amount of between-groups variance in speech-in-noise recognition. Little evidence of binaural summation was found. Head shadow was similar in magnitude for children with NH and with CIs, regardless of whether they wore one or two CIs. Children with HAs showed reduced head shadow effects. These outcomes suggest that in order to improve speech-in-noise recognition for children with hearing loss, intervention needs to be comprehensive, focusing on both language abilities and auditory mechanisms.

Pre-enlistment hearing loss and hearing loss disability among US soldiers and marines

Directory of Open Access Journals (Sweden)

Marlene E Gubata

2013-01-01

Full Text Available Hearing loss is a common condition among US adults, with some evidence of increasing prevalence in young adults. Noise-induced hearing loss attributable to employment is a significant source of preventable morbidity world-wide. The US military population is largely comprised of young adult males serving in a wide variety of occupations, many in high noise-level conditions, at least episodically. To identify accession and service-related risk factors for hearing-related disability, matched case-control study of US military personnel was conducted. Individuals evaluated for hearing loss disability in the US Army and Marine Corps were frequency matched to controls without history of disability evaluation on service and enlistment year. Conditional logistic regression was used to examine the association between accession and service-related factors and hearing-related disability evaluations between October 2002 and September 2010. Individuals with medically disqualifying audiograms or hearing loss diagnoses at application for military service were 8 and 4 times more likely, respectively, to have a disability evaluation related to hearing loss, after controlling for relevant accession, demographic, and service-related factors. Conservative hearing loss thresholds on pre-enlistment audiograms, stricter hearing loss medical waiver policies or qualified baseline audiograms pre-enlistment are needed in the U.S military. Industrial corporations or labor unions may also benefit from identifying individuals with moderate hearing loss at the time of employment to ensure use of personal protective equipment and engineer controls of noise.

5 CFR 1215.5 - Hearing.

Science.gov (United States)

2010-01-01

... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Hearing. 1215.5 Section 1215.5... § 1215.5 Hearing. (a) Request for hearing. (1) An employee must file a petition for a hearing in accordance with the instructions outlined in the agency's notice to offset. (2) A hearing may be requested by...

10 CFR 16.9 - Hearing.

Science.gov (United States)

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Hearing. 16.9 Section 16.9 Energy NUCLEAR REGULATORY... § 16.9 Hearing. (a) Request for hearing. (1) An employee shall file a petition for a hearing in... creditor agency, a hearing may be requested by filing a written petition stating why the employee disputes...

45 CFR 213.11 - Notice of hearing or opportunity for hearing.

Science.gov (United States)

2010-10-01

... 45 Public Welfare 2 2010-10-01 2010-10-01 false Notice of hearing or opportunity for hearing. 213.11 Section 213.11 Public Welfare Regulations Relating to Public Welfare OFFICE OF FAMILY ASSISTANCE (ASSISTANCE PROGRAMS), ADMINISTRATION FOR CHILDREN AND FAMILIES, DEPARTMENT OF HEALTH AND HUMAN SERVICES PRACTICE AND PROCEDURE FOR HEARINGS TO STATE...

42 CFR 430.70 - Notice of hearing or opportunity for hearing.

Science.gov (United States)

2010-10-01

... 42 Public Health 4 2010-10-01 2010-10-01 false Notice of hearing or opportunity for hearing. 430.70 Section 430.70 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL ASSISTANCE PROGRAMS GRANTS TO STATES FOR MEDICAL ASSISTANCE PROGRAMS Hearings on Conformity of State Medicaid Plans...

Prevention of the Evolution of Workers' Hearing Loss from Noise-Induced Hearing Loss in Noisy Environments through a Hearing Conservation Program

OpenAIRE

Fonseca, Vinicius Ribas; Marques, Jair; Panegalli, Flavio; Gonçalves, Claudia Giglio de Oliveira; Souza, Wesley

2016-01-01

Introduction Noise-induced hearing loss (NIHL) is a serious problem for workers and therefore for businesses. The hearing conservation program (HCP) is a set of coordinated measures to prevent the development or evolution of occupational hearing loss, which involves a continuous and dynamic process of implementation of hearing conservation routines through anticipation, recognition, evaluation, and subsequent control of the occurrence of existing environmental risks or of those thatmay exist...

Placoderm Assemblage from the Tetrapod-Bearing Locality of Strud (Belgium, Upper Famennian) Provides Evidence for a Fish Nursery

Science.gov (United States)

Clément, Gaël; Daeschler, Edward B.; Dupret, Vincent

2016-01-01

The placoderm fauna of the upper Famennian tetrapod-bearing locality of Strud, Belgium, includes the antiarch Grossilepis rikiki, the arthrodire groenlandaspidid Turrisaspis strudensis and the phyllolepidid Phyllolepis undulata. Based on morphological and morphometric evidence, the placoderm specimens from Strud are predominantly recognised as immature specimens and this locality as representing a placoderm nursery. The Strud depositional environment corresponds to a channel in an alluvial plain, and the presence of a nursery in such environment could have provided nutrients and protection to the placoderm offspring. This represents one of the earliest pieces of evidence for this sort of habitat partitioning in vertebrate history, with adults living more distantly from the nursery and using the nursery only to spawn or give live birth. PMID:27552196

12 CFR 308.155 - Hearing.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 4 2010-01-01 2010-01-01 false Hearing. 308.155 Section 308.155 Banks and... Pursuant to Section 32 of the FDIA § 308.155 Hearing. (a) Hearing dates. The Executive Secretary shall order a hearing to be commenced within 30 days after receipt of a request for a hearing filed pursuant...

19 CFR 111.67 - Hearing.

Science.gov (United States)

2010-04-01

... 19 Customs Duties 1 2010-04-01 2010-04-01 false Hearing. 111.67 Section 111.67 Customs Duties U.S... Revocation § 111.67 Hearing. (a) Hearing officer. The hearing officer must be an administrative law judge... right to examine all exhibits offered at the hearing and will have the right to cross-examine witnesses...

14 CFR 13.79 - Hearing.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hearing. 13.79 Section 13.79 Aeronautics....79 Hearing. If an alleged violator requests a hearing in accordance with § 13.75, the procedure of Subpart D of this part applies. At the close of the hearing, the Hearing Officer, on the record or...

45 CFR 16.11 - Hearing.

Science.gov (United States)

2010-10-01

... 45 Public Welfare 1 2010-10-01 2010-10-01 false Hearing. 16.11 Section 16.11 Public Welfare... BOARD § 16.11 Hearing. (a) Electing a hearing. If the appellant believes a hearing is appropriate, the... appeal file). The Board will approve a request (and may schedule a hearing on its own or in response to a...

Wordlikeness and Word Learning in Children with Hearing Loss

Science.gov (United States)

Stiles, Derek J.; McGregor, Karla K.; Bentler, Ruth A.

2013-01-01

Background: The more a novel word conforms to the phonotactics of the language, the more wordlike it is and the easier it is to learn. It is unknown to what extent children with hearing loss (CHL) take advantage of phonotactic cues to support word learning. Aims: This study investigated whether CHL had similar sensitivities to wordlikeness during…

Relation between speech-in-noise threshold, hearing loss and cognition from 40-69 years of age.

Science.gov (United States)

Moore, David R; Edmondson-Jones, Mark; Dawes, Piers; Fortnum, Heather; McCormack, Abby; Pierzycki, Robert H; Munro, Kevin J

2014-01-01

Healthy hearing depends on sensitive ears and adequate brain processing. Essential aspects of both hearing and cognition decline with advancing age, but it is largely unknown how one influences the other. The current standard measure of hearing, the pure-tone audiogram is not very cognitively demanding and does not predict well the most important yet challenging use of hearing, listening to speech in noisy environments. We analysed data from UK Biobank that asked 40-69 year olds about their hearing, and assessed their ability on tests of speech-in-noise hearing and cognition. About half a million volunteers were recruited through NHS registers. Respondents completed 'whole-body' testing in purpose-designed, community-based test centres across the UK. Objective hearing (spoken digit recognition in noise) and cognitive (reasoning, memory, processing speed) data were analysed using logistic and multiple regression methods. Speech hearing in noise declined exponentially with age for both sexes from about 50 years, differing from previous audiogram data that showed a more linear decline from speech-in-noise hearing was especially dramatic among those with lower cognitive scores. Decreasing cognitive ability and increasing age were both independently associated with decreasing ability to hear speech-in-noise (0.70 and 0.89 dB, respectively) among the population studied. Men subjectively reported up to 60% higher rates of difficulty hearing than women. Workplace noise history associated with difficulty in both subjective hearing and objective speech hearing in noise. Leisure noise history was associated with subjective, but not with objective difficulty hearing. Older people have declining cognitive processing ability associated with reduced ability to hear speech in noise, measured by recognition of recorded spoken digits. Subjective reports of hearing difficulty generally show a higher prevalence than objective measures, suggesting that current objective methods could

[Subclinical sensorineural hearing loss in female patients with rheumatoid arthritis].

Science.gov (United States)

Treviño-González, José Luis; Villegas-González, Mario Jesús; Muñoz-Maldonado, Gerardo Enrique; Montero-Cantu, Carlos Alberto; Nava-Zavala, Arnulfo Hernán; Garza-Elizondo, Mario Alberto

2015-01-01

The rheumatoid arthritis is a clinical entity capable to cause hearing impairment that can be diagnosed promptly with high frequencies audiometry. To detect subclinical sensorineural hearing loss in patients with rheumatoid arthritis. Cross-sectional study on patients with rheumatoid arthritis performing high frequency audiometry 125Hz to 16,000Hz and tympanometry. The results were correlated with markers of disease activity and response to therapy. High frequency audiometry was performed in 117 female patients aged from 19 to 65 years. Sensorineural hearing loss was observed at a sensitivity of pure tones from 125 to 8,000 Hz in 43.59%, a tone threshold of 10,000 to 16,000Hz in 94.02% patients in the right ear and in 95.73% in the left ear. Hearing was normal in 8 (6.84%) patients. Hearing loss was observed in 109 (93.16%), and was asymmetric in 36 (30.77%), symmetric in 73 (62.37%), bilateral in 107 (91.45%), unilateral in 2 (1.71%), and no conduction and/or mixed hearing loss was encountered. Eight (6.83%) patients presented vertigo, 24 (20.51%) tinnitus. Tympanogram type A presented in 88.90% in the right ear and 91.46% in the left ear, with 5.98 to 10.25% type As. Stapedius reflex was present in 75.3 to 85.2%. Speech discrimination in the left ear was significantly different (p = 0.02)in the group older than 50 years. No association was found regarding markers of disease activity, but there was an association with the onset of rheumatoid arthritis disease. Patients with rheumatoid arthritis had a high prevalence of sensorineural hearing loss for high and very high frequencies. Copyright © 2015 Academia Mexicana de Cirugía A.C. Published by Masson Doyma México S.A. All rights reserved.

Clinical measurement of various aspects of hearing impairment and their relation to auditory functioning: the development of an Auditory Profile

NARCIS (Netherlands)

van Esch, T.E.M.

2013-01-01

In terms of disability and handicap, problems in auditory function involve much more than a reduced sensitivity to soft sounds, the most commonly used measure of hearing impairment. In daily life, many hearing-impaired (HI) listeners suffer more from impaired processing of audible sounds, than from

Hear, Hear!

Science.gov (United States)

Rittner-Heir, Robbin

2000-01-01

Examines the problem of acoustics in school classrooms; the problems it creates for student learning, particularly for students with hearing problems; and the impediments to achieving acceptable acoustical levels for school classrooms. Acoustic guidelines are explored and some remedies for fixing sound problems are highlighted. (GR)

Photoanode of Dye-Sensitized Solar Cells Based on a ZnO/TiO2 Composite Film

Directory of Open Access Journals (Sweden)

Lu-Ting Yan

2012-01-01

Full Text Available A photoanode of dye-sensitized solar cells based on a ZnO/TiO2 composite film was fabricated on a transparent conductive glass substrate using different techniques including electrophoretic deposition, screen printing, and colloidal spray coating. The ZnOs used in the composite film were ZnO tetrapods prepared via thermal evaporation and ZnO nanorods obtained via hydrothermal growth. The structural and morphological characterizations of the thin composite films were carried out using scanning electron microscope (SEM. The best power conversion was 1.87%, which corresponds to the laminated TiO2/ZnO/TiO2 structure prepared via screen printing.

Cochlear implantation: is hearing preservation necessary in severe to profound hearing loss?

Science.gov (United States)

Derinsu, Ufuk; Serin, Gediz Murat; Akdaş, Ferda; Batman, Çağlar

2011-03-01

The goal of the cochlear implant surgery is to place the electrode array with minimal damage to preserve the residual hearing. Round-window insertion can be performed in a manner that is potentially less traumatic than the standard cochleostomy. The purpose of the study was to investigate audiological results of the round-window approach using standard electrode. A retrospective study was performed to evaluate our experience in patients with implanted through round window between January 2007 and March 2009. Sixty patients had undergone cochlear implant surgery through the round window with full insertion of a standard electrode array. Preoperative and postoperative pure-tone thresholds were measured for implanted ears in the range of 250 to 4000 Hz. Within these 60 cases, 31 patients had been evaluated. The population comprised 16 women and 15 men. The mean age was 15.96 years (range, 4-64 years). Follow-up times ranged from 6 to 26 months. Preservation of low-frequency hearing (250 and 500 Hz) was achieved in 27 (87%) of 31 patients. Complete hearing preservation (all frequencies) was accomplished in 11 patients (35.48%). No hearing could be determined postoperatively in 4 patients (12.9%), having preoperative thresholds of 120 dB at 250, 500, and 1000 Hz. Round-window approach has been widely used for preservation of residual hearing. In our patients with severe to profound hearing loss, we preserved residual hearing. Although the residual hearing cannot be sufficient for using additional acoustic stimulation, the preserved residual hearing means minimal damage and a more convenient cochlea, so this is promising for future development.

Hearing Disorders and Deafness

Science.gov (United States)

... enough to enjoy talking with friends or family. Hearing disorders make it hard, but not impossible, to ... often be helped. Deafness can keep you from hearing sound at all. What causes hearing loss? Some ...

Attitudes hearing impaired children face from hearing people : a case study from Wollega, Ethiopia

OpenAIRE

Olika, Ruth Erin Liselott

2009-01-01

The aim of this research is to find out what kind of attitudes that hearing impaired children face from hearing people, and how these attitudes influence the hearing impaired child’s life. This is a qualitative research project with interview as the instrument of collecting data. The interviews were conducted in Wollega, Ethiopia with four different informant groups: Children with hearing impairment (CWHI), their parents (Parents CWHI), Children with hearing (CWH), and their parents (Parents ...

Hearing Impairment

Science.gov (United States)

... Ear Hears Think about how you can feel speakers vibrate on your sound system or feel your throat vibrate when you speak. Sound, which is made up of invisible waves of energy, causes these vibrations. Hearing begins when sound waves that travel through ...

Vowel production of Mandarin-speaking hearing aid users with different types of hearing loss.

Directory of Open Access Journals (Sweden)

Yu-Chen Hung

Full Text Available In contrast with previous research focusing on cochlear implants, this study examined the speech performance of hearing aid users with conductive (n = 11, mixed (n = 10, and sensorineural hearing loss (n = 7 and compared it with the speech of hearing control. Speech intelligibility was evaluated by computing the vowel space area defined by the Mandarin Chinese corner vowels /a, u, i/. The acoustic differences between the vowels were assessed using the Euclidean distance. The results revealed that both the conductive and mixed hearing loss groups exhibited a reduced vowel working space, but no significant difference was found between the sensorineural hearing loss and normal hearing groups. An analysis using the Euclidean distance further showed that the compression of vowel space area in conductive hearing loss can be attributed to the substantial lowering of the second formant of /i/. The differences in vowel production between groups are discussed in terms of the occlusion effect and the signal transmission media of various hearing devices.

Does tinnitus, hearing asymmetry, or hearing loss predispose to occupational injury risk?

Science.gov (United States)

Cantley, Linda F; Galusha, Deron; Cullen, Mark R; Dixon-Ernst, Christine; Tessier-Sherman, Baylah; Slade, Martin D; Rabinowitz, Peter M; Neitzel, Richard L

2015-02-01

To determine the relative contributions of tinnitus, asymmetrical hearing loss, low frequency hearing loss (pure tone average of 0.5, 1, 2, 3 kHz; PTA.5123), or high frequency hearing loss (pure tone average of 4, 6 kHz; PTA46), to acute injury risk among a cohort of production and maintenance workers at six aluminum manufacturing plants, adjusting for ambient noise exposure and other recognized predictors of injury risk. Retrospective analysis. The study considered 9920 workers employed during 2003 to 2008. The cohort consisted of 8818 workers (89%) whose complete records were available. Adjusting for noise exposure and other recognized injury predictors, a 25% increased acute injury risk was observed among workers with a history of tinnitus in conjunction with high-frequency hearing loss (PTA46). Low frequency hearing loss may be associated with minor, yet less serious, injury risk. We did not find evidence that asymmetry contributes to injury risk. These results provide evidence that tinnitus, combined with high-frequency hearing loss, may pose an important safety threat to workers, especially those who work in high-noise exposed environments. These at risk workers may require careful examination of their communication and hearing protection needs.

Noise-Induced Hearing Loss

Science.gov (United States)

... Home » Health Info » Hearing, Ear Infections, and Deafness Noise-Induced Hearing Loss On this page: What is ... I find additional information about NIHL? What is noise-induced hearing loss? Every day, we experience sound ...

Auditory brainstem responses of CBA/J mice with neonatal conductive hearing losses and treatment with GM1 ganglioside.

Science.gov (United States)

Money, M K; Pippin, G W; Weaver, K E; Kirsch, J P; Webster, D B

1995-07-01

Exogenous administration of GM1 ganglioside to CBA/J mice with a neonatal conductive hearing loss ameliorates the atrophy of spiral ganglion neurons, ventral cochlear nucleus neurons, and ventral cochlear nucleus volume. The present investigation demonstrates the extent of a conductive loss caused by atresia and tests the hypothesis that GM1 ganglioside treatment will ameliorate the conductive hearing loss. Auditory brainstem responses were recorded from four groups of seven mice each: two groups received daily subcutaneous injections of saline (one group had normal hearing; the other had a conductive hearing loss); the other two groups received daily subcutaneous injections of GM1 ganglioside (one group had normal hearing; the other had a conductive hearing loss). In mice with a conductive loss, decreases in hearing sensitivity were greatest at high frequencies. The decreases were determined by comparing mean ABR thresholds of the conductive loss mice with those of normal hearing mice. The conductive hearing loss induced in the mice in this study was similar to that seen in humans with congenital aural atresias. GM1 ganglioside treatment had no significant effect on ABR wave I thresholds or latencies in either group.

Otolith morphology and hearing abilities in cave- and surface-dwelling ecotypes of the Atlantic molly, Poecilia mexicana (Teleostei: Poeciliidae)

Science.gov (United States)

Schulz-Mirbach, Tanja; Ladich, Friedrich; Riesch, Rüdiger; Plath, Martin

2010-01-01

Cave fish have rarely been investigated with regard to their inner ear morphology, hearing abilities, and acoustic communication. Based on a previous study that revealed morphological differences in the saccular otolith between a cave and two surface populations of Poecilia mexicana, we checked for additional differences in utricular and lagenar otoliths and tested whether different populations have similar hearing sensitivities. We found pronounced differences in the shape of all three otoliths. Otoliths of the saccule and lagena from cave fish differed from those of surface fish in the features of the face oriented towards the sensory epithelium. In addition, otoliths of the utricle and lagena were significantly heavier in cave fish. Auditory sensitivities were measured between 100 and 1500 Hz, utilizing the auditory evoked potential recording technique. We found similar hearing abilities in cave and surface fish, with greatest sensitivity between 200 and 300 Hz. An acoustic survey revealed that neither ecotype produced species-specific sounds. Our data indicate that cave dwelling altered the otolith morphology in Atlantic mollies, probably due to metabolic differences. Different otolith morphology, however, did not affect general auditory sensitivity or acoustic behavior. PMID:20430090

Bone-anchored hearing devices in children with unilateral conductive hearing loss: a patient-carer perspective.

Science.gov (United States)

Banga, Rupan; Doshi, Jayesh; Child, Anne; Pendleton, Elizabeth; Reid, Andrew; McDermott, Ann-Louise

2013-09-01

We sought to determine the outcome of implantation of a bone-anchored hearing device in children with unilateral conductive hearing loss. A retrospective case note analysis was used in a tertiary referral pediatric hospital to study 17 consecutive cases of pediatric patients with unilateral conductive hearing loss who were fitted with a bone-anchored hearing device between 2005 and 2010. The average age of the patients at the time of bone-anchored hearing device fitting was 10 years 6 months (range, 6 years 3 months to 16 years). Qualitative subjective outcome measures demonstrated benefit. The vast majority of patients reported improved social and physical functioning and improved quality of life. All 17 patients are currently using their bone-anchored hearing device on a daily basis after a follow-up of 6 months. This study has shown improved quality of life in children with unilateral hearing loss after implantation of their bone-anchored hearing device. There was a high degree of patient satisfaction and improvement in health status reported by children and/or carers. Bone-anchored hearing devices have an important role in the management of children with symptomatic unilateral hearing loss. Perhaps earlier consideration of a bone-anchored hearing device would be appropriate in selected cases.

Comparison of Carina active middle-ear implant with conventional hearing aids for mixed hearing loss.

Science.gov (United States)

Savaş, V A; Gündüz, B; Karamert, R; Cevizci, R; Düzlü, M; Tutar, H; Bayazit, Y A

2016-04-01

To compare the auditory outcomes of Carina middle-ear implants with those of conventional hearing aids in patients with moderate-to-severe mixed hearing loss. The study comprised nine patients (six males, three females) who underwent middle-ear implantation with Carina fully implantable active middle-ear implants to treat bilateral moderate-to-severe mixed hearing loss. The patients initially used conventional hearing aids and subsequently received the Carina implants. The hearing thresholds with implants and hearing aids were compared. There were no significant differences between: the pre-operative and post-operative air and bone conduction thresholds (p > 0.05), the thresholds with hearing aids and Carina implants (p > 0.05), or the pre-operative (mean, 72.8 ± 19 per cent) and post-operative (mean, 69.9 ± 24 per cent) speech discrimination scores (p > 0.05). One of the patients suffered total sensorineural hearing loss three months following implantation despite an initial 38 dB functional gain. All except one patient showed clinical improvements after implantation according to quality of life questionnaire (Glasgow Benefit Inventory) scores. Acceptance of Carina implants is better than with conventional hearing aids in patients with mixed hearing loss, although both yield similar hearing amplification. Cosmetic reasons appear to be critical for patient acceptance.

Auditory Brain Stem Processing in Reptiles and Amphibians: Roles of Coupled Ears

DEFF Research Database (Denmark)

Willis, Katie L.; Christensen-Dalsgaard, Jakob; Carr, Catherine

2014-01-01

Comparative approaches to the auditory system have yielded great insight into the evolution of sound localization circuits, particularly within the nonmammalian tetrapods. The fossil record demonstrates multiple appearances of tympanic hearing, and examination of the auditory brain stem of various...... groups can reveal the organizing effects of the ear across taxa. If the peripheral structures have a strongly organizing influence on the neural structures, then homologous neural structures should be observed only in groups with a homologous tympanic ear. Therefore, the central auditory systems...... of anurans (frogs), reptiles (including birds), and mammals should all be more similar within each group than among the groups. Although there is large variation in the peripheral auditory system, there is evidence that auditory brain stem nuclei in tetrapods are homologous and have similar functions among...

10 CFR 710.25 - Appointment of Hearing Officer; prehearing conference; commencement of hearings.

Science.gov (United States)

2010-01-01

... papers, issuing subpoenas for witnesses to attend the hearing or for the production of specific documents... extension of the hearing date past 90 calendar days from the date the request for hearing is received by the...

Intra-vaginal Zinc Oxide Tetrapod Nanoparticles as Novel Immunoprotective Agents against Genital Herpes

Science.gov (United States)

Antoine, Thessicar E.; Hadigal, Satvik R.; Yakoub, Abraam; Mishra, Yogendra K.; Bhattacharya, Palash; Haddad, Christine; Valyi-Nagy, Tibor; Adelung, Rainer; Prabhakar, Bellur S.; Shukla, Deepak

2016-01-01

Virtually all efforts to generate an effective protection against the life-long, recurrent genital infections caused by Herpes simplex virus-2 (HSV-2) have failed. Apart from sexual transmission, the virus can also be transmitted from mothers to neonates, and is a key facilitator of HIV co-acquisition. Here, we uncover a nanoimmunotherapy using specially designed Zinc Oxide Tetrapod Nanoparticles (ZOTEN) with engineered oxygen vacancies. We demonstrate that ZOTEN, when used intravaginally as a microbicide, is an effective suppressor of HSV-2 genital infection in female BALB/c mice. The strong HSV-2 trapping ability of ZOTEN significantly reduced the clinical signs of vaginal infection and effectively decreased animal mortality. In parallel, ZOTEN promoted the presentation of bound HSV-2 virions to mucosal antigen presenting cells, enhancing T cell- mediated and antibody-mediated responses to the infection, and thereby, suppressing a re-infection. We also found that ZOTEN exhibits strong adjuvant-like properties, which is highly comparable to alum, a commonly used adjuvant. Overall, our study provides very first evidence for the protective efficacy of an intravaginal microbicide/vaccine or microbivac platform against primary and secondary female genital herpes infections. PMID:27183601

78 FR 5556 - Public Hearing

Science.gov (United States)

2013-01-25

... SUSQUEHANNA RIVER BASIN COMMISSION Public Hearing AGENCY: Susquehanna River Basin Commission. ACTION: Notice. SUMMARY: The Susquehanna River Basin Commission will hold a public hearing on February 14, 2013, in Harrisburg, Pennsylvania. At this public hearing, the Commission will hear testimony on the...

77 FR 64576 - Public Hearing

Science.gov (United States)

2012-10-22

... SUSQUEHANNA RIVER BASIN COMMISSION Public Hearing AGENCY: Susquehanna River Basin Commission. ACTION: Notice. SUMMARY: The Susquehanna River Basin Commission will hold a public hearing on November 15, 2012, in Harrisburg, Pennsylvania. At this public hearing, the Commission will hear testimony on the...

78 FR 43961 - Public Hearing

Science.gov (United States)

2013-07-22

... SUSQUEHANNA RIVER BASIN COMMISSION Public Hearing AGENCY: Susquehanna River Basin Commission. ACTION: Notice. SUMMARY: The Susquehanna River Basin Commission will hold a public hearing on August 15, 2013, in Harrisburg, Pennsylvania. At this public hearing, the Commission will hear testimony on the...

77 FR 44703 - Public Hearing

Science.gov (United States)

2012-07-30

... SUSQUEHANNA RIVER BASIN COMMISSION Public Hearing AGENCY: Susquehanna River Basin Commission. ACTION: Notice. SUMMARY: The Susquehanna River Basin Commission will hold a public hearing on August 23, 2012, in Harrisburg, Pennsylvania. At this public hearing, the Commission will hear testimony on the...

78 FR 64260 - Public Hearing

Science.gov (United States)

2013-10-28

... SUSQUEHANNA RIVER BASIN COMMISSION Public Hearing AGENCY: Susquehanna River Basin Commission. ACTION: Notice. SUMMARY: The Susquehanna River Basin Commission will hold a public hearing on November 13, 2013, in Harrisburg, Pennsylvania. At this public hearing, the Commission will hear testimony on the...

Prevention of the Evolution of Workers' Hearing Loss from Noise-Induced Hearing Loss in Noisy Environments through a Hearing Conservation Program.

Science.gov (United States)

Fonseca, Vinicius Ribas; Marques, Jair; Panegalli, Flavio; Gonçalves, Claudia Giglio de Oliveira; Souza, Wesley

2016-01-01

Introduction Noise-induced hearing loss (NIHL) is a serious problem for workers and therefore for businesses. The hearing conservation program (HCP) is a set of coordinated measures to prevent the development or evolution of occupational hearing loss, which involves a continuous and dynamic process of implementation of hearing conservation routines through anticipation, recognition, evaluation, and subsequent control of the occurrence of existing environmental risks or of those that may exist in the workplace and lead to workers' hearing damage. Objective The aim of this study was to evaluate the effectiveness of the HCP in preventing further hearing loss in workers with audiograms suggestive of NIHL. The audiometric tests and medical records of 28 furniture company workers exposed to noise were reviewed and monitored for 2 years. Methods This retrospective, cross-sectional study examined five audiometric tests in the medical records (on admission and every semester) of 28 workers in a furniture company (totaling 140 audiometric exams) following the introduction of the HCP. Results Data analysis showed no differences between the audiometric tests conducted on admission and those performed every semester. Conclusions The HCP implemented was effective in preventing the worsening of hearing loss in workers already with NIHL when exposed to occupational noise. Therefore, such a measure could be useful for the employment of workers with hearing loss in job sectors that have noise exposure.

Prevention of the Evolution of Workers' Hearing Loss from Noise-Induced Hearing Loss in Noisy Environments through a Hearing Conservation Program

Science.gov (United States)

Fonseca, Vinicius Ribas; Marques, Jair; Panegalli, Flavio; Gonçalves, Claudia Giglio de Oliveira; Souza, Wesley

2015-01-01

Introduction Noise-induced hearing loss (NIHL) is a serious problem for workers and therefore for businesses. The hearing conservation program (HCP) is a set of coordinated measures to prevent the development or evolution of occupational hearing loss, which involves a continuous and dynamic process of implementation of hearing conservation routines through anticipation, recognition, evaluation, and subsequent control of the occurrence of existing environmental risks or of those that may exist in the workplace and lead to workers' hearing damage. Objective The aim of this study was to evaluate the effectiveness of the HCP in preventing further hearing loss in workers with audiograms suggestive of NIHL. The audiometric tests and medical records of 28 furniture company workers exposed to noise were reviewed and monitored for 2 years. Methods This retrospective, cross-sectional study examined five audiometric tests in the medical records (on admission and every semester) of 28 workers in a furniture company (totaling 140 audiometric exams) following the introduction of the HCP. Results Data analysis showed no differences between the audiometric tests conducted on admission and those performed every semester. Conclusions The HCP implemented was effective in preventing the worsening of hearing loss in workers already with NIHL when exposed to occupational noise. Therefore, such a measure could be useful for the employment of workers with hearing loss in job sectors that have noise exposure. PMID:26722345

Changes in auditory perceptions and cortex resulting from hearing recovery after extended congenital unilateral hearing loss

Directory of Open Access Journals (Sweden)

Jill B Firszt

2013-12-01

Full Text Available Monaural hearing induces auditory system reorganization. Imbalanced input also degrades time-intensity cues for sound localization and signal segregation for listening in noise. While there have been studies of bilateral auditory deprivation and later hearing restoration (e.g. cochlear implants, less is known about unilateral auditory deprivation and subsequent hearing improvement. We investigated effects of long-term congenital unilateral hearing loss on localization, speech understanding, and cortical organization following hearing recovery. Hearing in the congenitally affected ear of a 41 year old female improved significantly after stapedotomy and reconstruction. Pre-operative hearing threshold levels showed unilateral, mixed, moderately-severe to profound hearing loss. The contralateral ear had hearing threshold levels within normal limits. Testing was completed prior to, and three and nine months after surgery. Measurements were of sound localization with intensity-roved stimuli and speech recognition in various noise conditions. We also evoked magnetic resonance signals with monaural stimulation to the unaffected ear. Activation magnitudes were determined in core, belt, and parabelt auditory cortex regions via an interrupted single event design. Hearing improvement following 40 years of congenital unilateral hearing loss resulted in substantially improved sound localization and speech recognition in noise. Auditory cortex also reorganized. Contralateral auditory cortex responses were increased after hearing recovery and the extent of activated cortex was bilateral, including a greater portion of the posterior superior temporal plane. Thus, prolonged predominant monaural stimulation did not prevent auditory system changes consequent to restored binaural hearing. Results support future research of unilateral auditory deprivation effects and plasticity, with consideration for length of deprivation, age at hearing correction, degree and type

International hearing protector standardization

DEFF Research Database (Denmark)

Poulsen, Torben

2002-01-01

Hearing protectors shall fulfill some minimum requirements to their performance. As hearing protector manufacturers sell the products all over the world, the testing and certification of hearing protectors has become an international issue. The ISO working group WG17 under the headlines Acoustics...

Hearing loss in children with otitis media with effusion: a systematic review.

Science.gov (United States)

Cai, Ting; McPherson, Bradley

2017-02-01

Otitis media with effusion (OME) is the presence of non-purulent inflammation in the middle ear. Hearing impairment is frequently associated with OME. Pure tone audiometry and speech audiometry are two of the most primarily utilised auditory assessments and provide valuable behavioural and functional estimation on hearing loss. This paper was designed to review and analyse the effects of the presence of OME on children's listening abilities. A systematic and descriptive review. Twelve articles reporting frequency-specific pure tone thresholds and/or speech perception measures in children with OME were identified using PubMed, Ovid, Web of Science, ProQuest and Google Scholar search platforms. The hearing loss related to OME averages 18-35 dB HL. The air conduction configuration is roughly flat with a slight elevation at 2000 Hz and a nadir at 8000 Hz. Both speech-in-quiet and speech-in-noise perception have been found to be impaired. OME imposes a series of disadvantages on hearing sensitivity and speech perception in children. Further studies investigating the full range of frequency-specific pure tone thresholds, and that adopt standardised speech test materials are advocated to evaluate hearing related disabilities with greater comprehensiveness, comparability and enhanced consideration of their real life implications.

Hearing Screening Follow-Up: Completing the Process to Identify Hearing Health Needs

Science.gov (United States)

Eiserman, William; Shisler, Lenore; Hoffman, Jeff

2015-01-01

Hearing is at the heart of language development and school readiness; increasing numbers of Early Head Start programs have come to rely on otoacoustic emissions (OAE) technology to screen all infants and toddlers for hearing loss. Successful identification of hearing health needs is dependent not only on an appropriate screening method, but also…

Hearing loss induced by loud music among musicians of symphonic orchestra

Directory of Open Access Journals (Sweden)

Tanja Carli

2012-12-01

Full Text Available Noise-induced hearing loss is an important public health issue, especially among musicians who are, more than any other occupation, dependent on their hearing. For them, hearing impairment is due to too loud music, the effect of which, if exceeding the limit depending on the individual sensitivity of one’s ear, can be compared with theeffect of noise on the ear. Risk factors for its development are: the type of musical instrument and sound character, the way of playing, music genre or composition, duration of exposure to loud music, sound source and its distance from the ear, intervals of acoustic stimuli, individual factors and the musician’s position in the orchestra. Hearing impairment is greater at higher frequencies; in pure tone audiogram it is shown as notches between 3000 and 6000 Hz and is most frequent in the wind and brass section. Hearing loss is greater among violinists and typically affects the left ear owing to the sound source proximity and their position in the orchestra. The most common health problems take the form of diplacusis, algiacusis and tinnitus, as exposure to the loud acoustic stimulus above 90 dB(A cause damage to the inner ear, the so-called acoustic trauma. Use of personal protective equipment among musicians is low especially because of too much high-frequency attenuation and occlusion effect.

Energy transmittance predicts conductive hearing loss in older children and adults

Science.gov (United States)

Keefe, Douglas H.; Simmons, Jeffrey L.

2003-12-01

The test performance of a wideband acoustic transfer function (ATF) test and 226-Hz tympanometry was assessed in predicting the presence of conductive hearing loss, based on an air-bone gap of 20 dB or more. Two ATF tests were designed using an improved calibration method over a frequency range (0.25-8 kHz): an ambient-pressure test and a tympanometric test using an excess static pressure in the ear canal. Wideband responses were objectively classified using moment analyses of energy transmittance, which was a more appropriate test variable than energy reflectance. Subjects included adults and children of age 10 years and up, with 42 normal-functioning ears and 18 ears with a conductive hearing loss. Predictors were based on the magnitudes of the moment deviations from the 10th to 90th percentiles of the normal group. Comparing tests at a fixed specificity of 0.90, the sensitivities were 0.28 for peak-compensated static acoustic admittance at 226 Hz, 0.72 for ambient-pressure ATF, and 0.94 for pressurized ATF. Pressurized ATF was accurate at predicting conductive hearing loss with an area under the receiver operating characteristic curve of 0.95. Ambient-pressure ATF may have sufficient accuracy to use in some hearing-screening applications, whereas pressurized ATF has additional accuracy that may be appropriate for hearing-diagnostic applications.

The South African English Smartphone Digits-in-Noise Hearing Test: Effect of Age, Hearing Loss, and Speaking Competence.

Science.gov (United States)

Potgieter, Jenni-Marí; Swanepoel, De Wet; Myburgh, Hermanus Carel; Smits, Cas

2017-11-20

This study determined the effect of hearing loss and English-speaking competency on the South African English digits-in-noise hearing test to evaluate its suitability for use across native (N) and non-native (NN) speakers. A prospective cross-sectional cohort study of N and NN English adults with and without sensorineural hearing loss compared pure-tone air conduction thresholds to the speech reception threshold (SRT) recorded with the smartphone digits-in-noise hearing test. A rating scale was used for NN English listeners' self-reported competence in speaking English. This study consisted of 454 adult listeners (164 male, 290 female; range 16 to 90 years), of whom 337 listeners had a best ear four-frequency pure-tone average (4FPTA; 0.5, 1, 2, and 4 kHz) of ≤25 dB HL. A linear regression model identified three predictors of the digits-in-noise SRT, namely, 4FPTA, age, and self-reported English-speaking competence. The NN group with poor self-reported English-speaking competence (≤5/10) performed significantly (p English-speaking competence for the N and NN groups (≥6/10) and NN group alone (≤5/10). Logistic regression models, which include age in the analysis, showed a further improvement in sensitivity and specificity for both groups (area under the receiver operating characteristic curve, 0.962 and 0.903, respectively). Self-reported English-speaking competence had a significant influence on the SRT obtained with the smartphone digits-in-noise test. A logistic regression approach considering SRT, self-reported English-speaking competence, and age as predictors of best ear 4FPTA >25 dB HL showed that the test can be used as an accurate hearing screening tool for N and NN English speakers. The smartphone digits-in-noise test, therefore, allows testing in a multilingual population familiar with English digits using dynamic cutoff values that can be chosen according to self-reported English-speaking competence and age.

Age-Related Hearing Loss: Quality of Care for Quality of Life

Science.gov (United States)

Li-Korotky, Ha-Sheng

2012-01-01

Age-related hearing loss (ARHL), known as presbycusis, is characterized by progressive deterioration of auditory sensitivity, loss of the auditory sensory cells, and central processing functions associated with the aging process. ARHL is the third most prevalent chronic condition in older Americans, after hypertension and arthritis, and is a…

Self-Assessment of Hearing and Purchase of Hearing Aids by Middle-Aged and Elderly Adults

Directory of Open Access Journals (Sweden)

Otavio, Andressa Colares da Costa

2015-06-01

Full Text Available Introduction Presbycusis is a consequence of aging. Prescription of hearing aids is part of the treatment, although the prevalence of use by elderly people is still small. Objective To verify whether or not self-assessment of hearing is a predictor for purchase of hearing aids. Methods Quantitative, cross-sectional, descriptive, and observational study. Participants were subjects who sought a private hearing center for selection of hearing aids. During the diagnostic interview, subjects answered the following question: “On a scale of 1 to 10, with 1 being the worst and 10 the best, how would you rate your overall hearing ability?” After that, subjects underwent audiometry, selected a hearing aid, performed a home trial, and decided whether or not to purchase the hearing aid. The variables were associated and analyzed statistically. Results The sample was comprised of 32 subjects, both men and women, with a higher number of women. Mean age was 71.41 ± 12.14 years. Self-assessment of hearing ranged from 2 to 9 points. Overall, 71.9% of the subjects purchased hearing aids. There was no association between scores in the self-assessment and the purchase of hearing aids (p = 0.263. Among those who scored between 2 and 5 points, 64.7% purchased the device; between 6 and 7 points, 76.09% purchased the device; and between 8 and 9 points, 50% purchased the device, respectively. Conclusion There is evidence that low self-assessment scores lead to the purchase of hearing aids, although no significant association was observed in the sample.

5 CFR 831.1106 - Hearing.

Science.gov (United States)

2010-01-01

... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Hearing. 831.1106 Section 831.1106...) RETIREMENT Prohibition on Payments of Annuities § 831.1106 Hearing. (a) OPM's hearing examiner shall preside at any hearing held pursuant to this subpart, unless OPM designates another presiding officer. The...

Efficient evaluation of hearing ability

NARCIS (Netherlands)

2009-01-01

A system for establishing a hearing ability model of a hearing ability of a person, includes a data storage configured to store a representation of a distribution of a hearing ability of a population of individuals, and a processor configured to establish a hearing ability model representing a

49 CFR 209.321 - Hearing.

Science.gov (United States)

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Hearing. 209.321 Section 209.321 Transportation... TRANSPORTATION RAILROAD SAFETY ENFORCEMENT PROCEDURES Disqualification Procedures § 209.321 Hearing. (a) Upon receipt of a hearing request complying with § 209.311, an administrative hearing for review of a notice of...

Newborn hearing screening and strategy for early detection of hearing loss in infants.

Science.gov (United States)

Jakubíková, Janka; Kabátová, Zuzana; Pavlovcinová, Gabriela; Profant, Milan

2009-04-01

More than 80% of permanent hearing losses (HL) in children are congenital. Newborn hearing screening (NHS) is the best method for early detection of suspected hearing loss. If the NHS is not universal more than 30% permanent hearing losses are not identified. There are various methods of NHS: otoacoustic emissions (TEOAE, DPOAE) and automatic auditory brainstem response (AABR). After hearing screening, and when hearing loss is suspected, tympanometry and audiological methods then used for determination of hearing threshold; these include ABR, ASSR or/and behavioral methods. The goal of this study is to evaluate the influence of UNHS on the early detection of hearing loss in children before and after the implementation of obligatory universal newborn hearing screening in Slovakia, and also on the etiologic evaluation of hearing impaired infants identified by screening. In Slovakia NHS started in 1998 and was provided in ENT departments. From May 1, 2006 UNHS has been mandatory in Slovakia, using two stages TEOAE in all newborn departments in Slovakia (64 newborn departments). In year 2005--42% of newborns in Slovakia were screened, in 2006--66% newborns and in 2007--94, 99% (three small newborn departments do not yet have equipment for OAE screening). For determination of hearing thresholds ASSR are used in two ENT departments and ABR in the other four ENT departments. Comparing the number of identified cases with bilateral severe permanent HL or deafness before and after UNHS, 22.8% more cases of PHL were identified in the first year of UNHS. Also the average age of diagnosis of PHL was lower. In the year 2007, 94% of newborns were screened. We found 0.947/1000 newborns with bilateral severe PHL (35.9%) more than before UNHS). After audiologic and etiologic assessment of the 76 infants who failed screening, 5 (6.58%) were found to have normal hearing, 16 (22.54%) had unilateral and 55 (77.46%) had bilateral SNHL. A non-syndromic genetic cause was present in 25

The development and standardization of Self-assessment for Hearing Screening of the Elderly.

Science.gov (United States)

Kim, Gibbeum; Na, Wondo; Kim, Gungu; Han, Woojae; Kim, Jinsook

2016-01-01

The present study aimed to develop and standardize a screening tool for elderly people who wish to check for themselves their level of hearing loss. The Self-assessment for Hearing Screening of the Elderly (SHSE) consisted of 20 questions based on the characteristics of presbycusis using a five-point scale: seven questions covered general issues related to sensorineural hearing loss, seven covered hearing difficulty under distracting listening conditions, two covered hearing difficulty with fast-rated speech, and four covered the working memory function during communication. To standardize SHSE, 83 elderly participants took part in the study: 25 with normal hearing, and 22, 23, and 13 with mild, moderate, and moderate-to-severe sensorineural hearing loss, respectively, according to their hearing sensitivity. All were retested 3 weeks later using the same questionnaire to confirm its reliability. In addition, validity was assessed using various hearing tests such as a sentence test with background noise, a time-compressed speech test, and a digit span test. SHSE and its subcategories showed good internal consistency. SHSE and its subcategories demonstrated high test-retest reliability. A high correlation was observed between the total scores and pure-tone thresholds, which indicated gradually increased SHSE scores of 42.24%, 55.27%, 66.61%, and 78.15% for normal hearing, mild, moderate, and moderate-to-severe groups, respectively. With regard to construct validity, SHSE showed a high negative correlation with speech perception scores in noise and a moderate negative correlation with scores of time-compressed speech perception. However, there was no statistical correlation between digit span results and either the SHSE total or its subcategories. A confirmatory factor analysis supported three factors in SHSE. We found that the developed SHSE had valuable internal consistency, test-retest reliability, and convergent and construct validity. These results suggest that

Preferred Compression Speed for Speech and Music and Its Relationship to Sensitivity to Temporal Fine Structure.

Science.gov (United States)

Moore, Brian C J; Sęk, Aleksander

2016-09-07

Multichannel amplitude compression is widely used in hearing aids. The preferred compression speed varies across individuals. Moore (2008) suggested that reduced sensitivity to temporal fine structure (TFS) may be associated with preference for slow compression. This idea was tested using a simulated hearing aid. It was also assessed whether preferences for compression speed depend on the type of stimulus: speech or music. Twenty-two hearing-impaired subjects were tested, and the stimulated hearing aid was fitted individually using the CAM2A method. On each trial, a given segment of speech or music was presented twice. One segment was processed with fast compression and the other with slow compression, and the order was balanced across trials. The subject indicated which segment was preferred and by how much. On average, slow compression was preferred over fast compression, more so for music, but there were distinct individual differences, which were highly correlated for speech and music. Sensitivity to TFS was assessed using the difference limen for frequency at 2000 Hz and by two measures of sensitivity to interaural phase at low frequencies. The results for the difference limens for frequency, but not the measures of sensitivity to interaural phase, supported the suggestion that preference for compression speed is affected by sensitivity to TFS. © The Author(s) 2016.

Temporal and speech processing skills in normal hearing individuals exposed to occupational noise.

Science.gov (United States)

Kumar, U Ajith; Ameenudin, Syed; Sangamanatha, A V

2012-01-01

Prolonged exposure to high levels of occupational noise can cause damage to hair cells in the cochlea and result in permanent noise-induced cochlear hearing loss. Consequences of cochlear hearing loss on speech perception and psychophysical abilities have been well documented. Primary goal of this research was to explore temporal processing and speech perception Skills in individuals who are exposed to occupational noise of more than 80 dBA and not yet incurred clinically significant threshold shifts. Contribution of temporal processing skills to speech perception in adverse listening situation was also evaluated. A total of 118 participants took part in this research. Participants comprised three groups of train drivers in the age range of 30-40 (n= 13), 41 50 ( = 13), 41-50 (n = 9), and 51-60 (n = 6) years and their non-noise-exposed counterparts (n = 30 in each age group). Participants of all the groups including the train drivers had hearing sensitivity within 25 dB HL in the octave frequencies between 250 and 8 kHz. Temporal processing was evaluated using gap detection, modulation detection, and duration pattern tests. Speech recognition was tested in presence multi-talker babble at -5dB SNR. Differences between experimental and control groups were analyzed using ANOVA and independent sample t-tests. Results showed a trend of reduced temporal processing skills in individuals with noise exposure. These deficits were observed despite normal peripheral hearing sensitivity. Speech recognition scores in the presence of noise were also significantly poor in noise-exposed group. Furthermore, poor temporal processing skills partially accounted for the speech recognition difficulties exhibited by the noise-exposed individuals. These results suggest that noise can cause significant distortions in the processing of suprathreshold temporal cues which may add to difficulties in hearing in adverse listening conditions.

Temporal and speech processing skills in normal hearing individuals exposed to occupational noise

Directory of Open Access Journals (Sweden)

U Ajith Kumar

2012-01-01

Full Text Available Prolonged exposure to high levels of occupational noise can cause damage to hair cells in the cochlea and result in permanent noise-induced cochlear hearing loss. Consequences of cochlear hearing loss on speech perception and psychophysical abilities have been well documented. Primary goal of this research was to explore temporal processing and speech perception Skills in individuals who are exposed to occupational noise of more than 80 dBA and not yet incurred clinically significant threshold shifts. Contribution of temporal processing skills to speech perception in adverse listening situation was also evaluated. A total of 118 participants took part in this research. Participants comprised three groups of train drivers in the age range of 30-40 (n= 13, 41 50 ( = 13, 41-50 (n = 9, and 51-60 (n = 6 years and their non-noise-exposed counterparts (n = 30 in each age group. Participants of all the groups including the train drivers had hearing sensitivity within 25 dB HL in the octave frequencies between 250 and 8 kHz. Temporal processing was evaluated using gap detection, modulation detection, and duration pattern tests. Speech recognition was tested in presence multi-talker babble at -5dB SNR. Differences between experimental and control groups were analyzed using ANOVA and independent sample t-tests. Results showed a trend of reduced temporal processing skills in individuals with noise exposure. These deficits were observed despite normal peripheral hearing sensitivity. Speech recognition scores in the presence of noise were also significantly poor in noise-exposed group. Furthermore, poor temporal processing skills partially accounted for the speech recognition difficulties exhibited by the noise-exposed individuals. These results suggest that noise can cause significant distortions in the processing of suprathreshold temporal cues which may add to difficulties in hearing in adverse listening conditions.

15 CFR 90.14 - Hearing.

Science.gov (United States)

2010-01-01

... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Hearing. 90.14 Section 90.14 Commerce... OF COMMERCE PROCEDURE FOR CHALLENGING CERTAIN POPULATION AND INCOME ESTIMATES § 90.14 Hearing. (a) The hearing shall be conducted by the same hearing officer who collected the documentary evidence, if...

47 CFR 1.1928 - Hearing.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 1 2010-10-01 2010-10-01 false Hearing. 1.1928 Section 1.1928... United States Salary Offset-Individual Debt § 1.1928 Hearing. (a) Petition for hearing. (1) An employee may request a hearing by filing a written petition with the Managing Director of the Commission, or...

19 CFR 354.12 - Hearing.

Science.gov (United States)

2010-04-01

... 19 Customs Duties 3 2010-04-01 2010-04-01 false Hearing. 354.12 Section 354.12 Customs Duties... ANTIDUMPING OR COUNTERVAILING DUTY ADMINISTRATIVE PROTECTIVE ORDER § 354.12 Hearing. (a) Scheduling of hearing. The presiding official will schedule the hearing at a reasonable time, date, and place, which will be...

Comparative and developmental patterns of amphibious auditory function in salamanders.

Science.gov (United States)

Zeyl, Jeffrey N; Johnston, Carol E

2016-12-01

Early amphibious tetrapods may have detected aquatic sound pressure using sound-induced lung vibrations, but their lack of tympanic middle ears would have restricted aerial sensitivity. Sharing these characteristics, salamanders could be models for the carryover of auditory function across an aquatic-terrestrial boundary without tympanic middle ears. We measured amphibious auditory evoked potential audiograms in five phylogenetically and ecologically distinct salamanders (Amphiuma means, Notophthalmus viridescens, Ambystoma talpoideum, Eurycea spp., and Plethodon glutinosus) and tested whether metamorphosis and terrestrial niche were linked to aerial sensitivity. Threshold differences between media varied between species. A. means' relative aerial sensitivity was greatest at 100 Hz and decreased with increasing frequency. In contrast, all other salamanders retained greater sensitivity up to 500 Hz, and in A. talpoideum and Eurycea, relative sensitivity at 500 Hz was higher than at 100 Hz. Aerial thresholds of terrestrial P. glutinosus above 200 Hz were similar to A. talpoideum and Eurycea, but lower than N. viridescens and A. means. Metamorphosis did not affect aerial sensitivity in N. viridescens or A. talpoideum. These results fail to support a hypothesis of terrestrial hearing specialization across ontogeny or phylogeny. We discuss methodological limitations to our amphibious comparisons and factors affecting variation in amphibious performance.

Newborn hearing screening vs later hearing screening and developmental outcomes in children with permanent childhood hearing impairment

NARCIS (Netherlands)

Korver, Anna M. H.; Konings, Saskia; Dekker, Friedo W.; Beers, Mieke; Wever, Capi C.; Frijns, Johan H. M.; Oudesluys-Murphy, Anne M.; de Vries, Jutte; Vossen, Ann; Kant, Sarina; van den Akker-van Marle, Elske; le Cessie, Saskia; Rieffe, Carolien; Ens-Dokkum, Martina; van Straaten, Irma; Uilenburg, Noelle; Elvers, Bert; Loeber, Gerard; Meuwese-Jongejeugd, Anneke; Maré, Marcel; van Zanten, Bert; Goedegebure, André; Coster, Francien; van Dijk, Pim; Goverts, Theo; Admiraal, Ronald; Cremers, Cor; Kunst, Dirk; de Leeuw, Marina; Dijkhuizen, Janette; Scharloo, Marleen; Hoeben, Dirk; Rijpma, Gerti; Graef, Wim; Linschoten, Dik; Kuijper, Jessica; Hof, Nanda; Koldewijn, Reinoud; Pans, Donné; Jorritsma, Frank; van Beurden, Maarten; ter Huurne, Christien; Brienesse, Patrick; Seekles, Lisanne; de Jong, Jantine; Thijssen, Andrea; Lievense, Andrea; van Egdom-van der Wind, Marina; Theunissen, Stephanie; Mooij, Sophie

2010-01-01

Newborn hearing screening programs have been implemented in many countries because it was thought that the earlier permanent childhood hearing impairment is detected, the less developmentally disadvantaged children would become. To date, however, no strong evidence exists for universal introduction

Comparison of reading comprehension and working memory in hearing-impaired and normal-hearing children

Directory of Open Access Journals (Sweden)

Mohammad Rezaei

2013-03-01

Full Text Available Background and Aim: Reading is the most important human need for learning. In normal-hearing people working memory is a predictor of reading comprehension. In this study the relationship between working memory and reading comprehension skills was studied in hearing-impaired children, and then compared with the normal-hearing group.Methods: This was a descriptive-analytic study. The working memory and reading comprehension skills of 18 (8 male, 10 female sever hearing-impaired children in year five of exceptional schools were compared by means of a reading test with 18 hearing children as control group. The subjects in the control group were of the same gender and educational level of the sample group.Results: The children with hearing loss performed similarly to the normal-hearing children in tasks related to auditory-verbal memory of sounds (reverse, visual-verbal memory of letters, and visual-verbal memory of pictures. However, they showed lower levels of performance in reading comprehension (p<0.001. Moreover, no significant relationship was observed between working memory and reading comprehension skills.Conclusion: Findings indicated that children with hearing loss have a significant impairment in the reading comprehension skill. Impairment in language knowledge and vocabulary may be the main cause of poor reading comprehension in these children. In hearing-impaired children working memory is not a strong predictor of reading comprehension.

29 CFR 2200.209 - Hearing.

Science.gov (United States)

2010-07-01

... 29 Labor 9 2010-07-01 2010-07-01 false Hearing. 2200.209 Section 2200.209 Labor Regulations... Simplified Proceedings § 2200.209 Hearing. (a) Procedures. As soon as practicable after the conclusion of the pre-hearing conference, the Judge will hold a hearing on any issue that remains in dispute. The...

5 CFR 1639.23 - Hearing.

Science.gov (United States)

2010-01-01

... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Hearing. 1639.23 Section 1639.23... Hearing. (a) Request for hearing. Except as provided in paragraph (b) of this section, an employee who desires a hearing concerning the existence or amount of the debt or the proposed offset schedule must send...

45 CFR 607.5 - Hearing.

Science.gov (United States)

2010-10-01

... 45 Public Welfare 3 2010-10-01 2010-10-01 false Hearing. 607.5 Section 607.5 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION SALARY OFFSET § 607.5 Hearing. (a) Request for hearing. (1) An employee may file a petition for an oral or paper hearing in...

7 CFR 900.115 - Hearing.

Science.gov (United States)

2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Hearing. 900.115 Section 900.115 Agriculture... Hearing. (a) The arbitrator shall have full discretion to conduct the hearing in such manner as will, in..., and other experts. (h) When more than two arbitrators are designated to hear a dispute, and they...

Deafness and Hearing Loss.

Science.gov (United States)

National Information Center for Children and Youth with Disabilities, Washington, DC.

This brief overview provides information on the definition, incidence, and characteristics of children with hearing impairments and deafness. The federal definitions of hearing impairment and deafness are provided. The different types of hearing loss are noted, including: (1) conductive (caused by diseases or obstructions in the outer or middle…

Influence of Loudness Compression on Hearing with Bone Anchored Hearing Implants

OpenAIRE

Kurz, Anja; Caversaccio, Marco; Kompis, Martin; Flynn, Marc

2014-01-01

Bone Anchored Hearing Implants (BAHI) are routinely used in patients with conductive or mixed hearing loss, e.g. if conventional air conduction hearing aids cannot be used. New sound processors and new fitting software now allow the adjustment of parameters such as loudness compression ratios or maximum power output separately. Today it is unclear, how the choice of these parameters influences aided speech understanding in BAHI users. In this prospective experimental study, the effect ...

Objective Scaling of Sound Quality for Normal-Hearing and Hearing-Impaired Listeners

DEFF Research Database (Denmark)

Nielsen, Lars Bramsløw

) Subjective sound quality ratings of clean and distorted speech and music signals, by normal-hearing and hearing-impaired listeners, to provide reference data, 2) An auditory model of the ear, including the effects of hearing loss, based on existing psychoacoustic knowledge, coupled to 3) An artificial neural......A new method for the objective estimation of sound quality for both normal-hearing and hearing-impaired listeners has been presented: OSSQAR (Objective Scaling of Sound Quality and Reproduction). OSSQAR is based on three main parts, which have been carried out and documented separately: 1...... network, which was trained to predict the sound quality ratings. OSSQAR predicts the perceived sound quality on two independent perceptual rating scales: Clearness and Sharpness. These two scales were shown to be the most relevant for assessment of sound quality, and they were interpreted the same way...

Hearing aid adjustment

DEFF Research Database (Denmark)

Heinemann, Trine; Matthews, Ben; Raudaskoski, Pirkko Liisa

2012-01-01

to the interaction during hearing aid fitting. This report of a Danish pilot study describes two such problems. The first problem arises from the requirement that the audiologist needs to ‘translate’ the patient’s subjective hearing description for making technological decisions. The second problem is the way...... in which the hearing aid user’s implicit and often unrealistic expectations are handled. This kind of research has potential application for developing a model of best practices....

45 CFR 33.6 - Hearings.

Science.gov (United States)

2010-10-01

... adjudication and need not take the form of an evidentiary hearing, i.e., the rules of evidence need not apply... information developed at the hearing, as soon as practicable after the hearing, but not later than sixty (60) days after the date on which the hearing petition was received by the creditor agency, unless the...

45 CFR 1179.5 - Hearing.

Science.gov (United States)

2010-10-01

... 45 Public Welfare 3 2010-10-01 2010-10-01 false Hearing. 1179.5 Section 1179.5 Public Welfare... ENDOWMENT FOR THE HUMANITIES SALARY OFFSET § 1179.5 Hearing. (a) Request for hearing. (1) An employee must file a petition for a hearing in accordance with the instructions outlined in the agency's notice to...

45 CFR 1606.8 - Hearing.

Science.gov (United States)

2010-10-01

... 45 Public Welfare 4 2010-10-01 2010-10-01 false Hearing. 1606.8 Section 1606.8 Public Welfare... PROCEDURES; RECOMPETITION § 1606.8 Hearing. (a) The recipient may make written request for a hearing within... days after receipt of a request for a hearing, the Corporation shall notify the recipient in writing of...

10 CFR 2.1405 - Hearing.

Science.gov (United States)

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Hearing. 2.1405 Section 2.1405 Energy NUCLEAR REGULATORY... with Oral Hearings § 2.1405 Hearing. (a) No later than twenty (20) days after the conclusion of the prehearing conference, the presiding officer shall hold a hearing on any contention that remains in dispute...

12 CFR 308.142 - Hearing.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 4 2010-01-01 2010-01-01 false Hearing. 308.142 Section 308.142 Banks and... Exchange Act of 1934 § 308.142 Hearing. (a) Proceedings are informal. Formal rules of evidence, the... Local Rules shall not apply to hearings under this subpart. (b) Hearing Procedure. (1) Parties to the...

34 CFR 300.181 - Hearing procedures.

Science.gov (United States)

2010-07-01

... evidentiary hearing and estimation of time for each presentation; or (E) Completion of the review and the... of the parties during the proceedings. The Hearing Official or Hearing Panel takes all steps... disposition of the case. (2) The Hearing Official or Hearing Panel may schedule a prehearing conference with...

Cognitive behaviour modification: a technique for teaching subtraction skills to hearing and deaf/hard-of-hearing elementary students.

Science.gov (United States)

Al-Hilawani, Y A

2000-09-01

The purpose of this study was to examine the influence of using the Cognitive Behaviour Modification (CBM) technique on the subtraction skills of third grade hearing and deaf/hard-of-hearing students. The results indicated that the CBM deaf/hard-of-hearing students and the CBM and non-CBM hearing students made more progress in solving the subtraction problems than the non-CBM deaf/hard-of-hearing students. The results also showed that there were no significant differences between the CBM deaf/hard-of-hearing and the non-CBM hearing students; and there were no significant differences between the CBM and non-CBM hearing students. The results revealed that the CBM hearing students achieved significantly higher post-test scores than the CBM deaf/hard-of-hearing students. However, the CBM deaf/hard-of-hearing students obtained a significantly higher gain score compared to the CBM and non-CBM hearing students. Implications for teachers and suggestions for future research are discussed in this paper.

Is Hearing Impairment Associated with Rheumatoid Arthritis?

DEFF Research Database (Denmark)

Emamifar, Amir; Bjoerndal, Kristine; Jensen Hansen, Inger Marie

2016-01-01

BACKGROUND: Rheumatoid arthritis (RA) is a systemic, inflammatory disease that affects 1% of the population. The auditory system may be involved during the course of disease; however the association of RA and hearing impairment has not been clearly defined. OBJECTIVE: The objective of this review...... is to evaluate published clinical reports related to hearing impairment in patients with RA. Furthermore, we discuss possible pathologies and associated factors as well as new treatment modalities. METHOD: A thorough literature search was performed using available databases including Pubmed, Embase, Cochrane...... and ComDisDome to cover all relative reports. The following keywords were used: hearing loss, hearing difficulties, hearing disorders, hearing impairment, sensorineural hearing loss, conductive hearing loss, mixed hearing loss, autoimmune hearing loss, drug ototoxicity, drug-induced hearing loss, hearing...

19 CFR 207.66 - Hearing.

Science.gov (United States)

2010-04-01

... 19 Customs Duties 3 2010-04-01 2010-04-01 false Hearing. 207.66 Section 207.66 Customs Duties... EXPORTS TO THE UNITED STATES Five-Year Reviews § 207.66 Hearing. (a) In general. The Commission shall hold a hearing in each full review. The date of the hearing shall be specified in the scheduling notice...

29 CFR 101.34 - Hearing.

Science.gov (United States)

2010-07-01

... 29 Labor 2 2010-07-01 2010-07-01 false Hearing. 101.34 Section 101.34 Labor Regulations Relating... Section 10(k) of the Act § 101.34 Hearing. If the parties have not adjusted the dispute or agreed upon methods of voluntary adjustment, a hearing, usually open to the public, is held before a hearing officer...

29 CFR 4221.6 - Hearing.

Science.gov (United States)

2010-07-01

... 29 Labor 9 2010-07-01 2010-07-01 false Hearing. 4221.6 Section 4221.6 Labor Regulations Relating... PLANS ARBITRATION OF DISPUTES IN MULTIEMPLOYER PLANS § 4221.6 Hearing. (a) Time and place of hearing established. Unless the parties agree to proceed without a hearing as provided in § 4221.5(c), the parties and...

Hearing loss at work? Hearing loss from leisure activities?

CERN Multimedia

2006-01-01

The nurses of the Medical Service would like invite all persons working on the CERN site to take part in a: HEARING LOSS DETECTION WEEK From 28 August to 1st September 2006 At the Infirmary, Building 57 from 9 a.m. to 4 p.m. Hearing tests - advice - information - documentation - protective equipment

Hear, hear, what, what

Energy Technology Data Exchange (ETDEWEB)

1985-02-01

Noise is now the most serious health hazard in industry. People risk suffering severe damage to their hearing and health generally through exposure to noise levels which exceed the risk limit of 95-90 dB(A). Stress related problems are often directly the result of exposure to noise. Furthermore, noise leads to reduced productivity, increased absenteeism and compensation claims. In a series of eight reports, Bilson technologists detail the specific noise problems commonly encountered in each of the major areas of industry. These range from the concrete and construction industry through sawmilling, wood working, mining and mechanical engineering, to textile and food manufacture. This report discusses the noise in mining, considering drills, load haul dump machines, surface mines, earth moving equipment, treatment plants, frequency spectra of noise, and finally, choice of hearing protection.

Deaf/Hearing Research Partnerships

Science.gov (United States)

Wolsey, Ju-Lee A.; Misener Dunn, Kim; Gentzke, Scott W.; Joharchi, Hannah A.; Clark, M. Diane

2017-01-01

Deaf individuals typically are seen through the lens of the dominant hearing society's perception, i.e., that being deaf is an impairment. Today, a small but growing number of Deaf and hearing researchers are challenging this perception. The authors examined perceptions of what components are necessary for a successful Deaf/hearing research…

Improvements in speech understanding with wireless binaural broadband digital hearing instruments in adults with sensorineural hearing loss.

Science.gov (United States)

Kreisman, Brian M; Mazevski, Annette G; Schum, Donald J; Sockalingam, Ravichandran

2010-03-01

This investigation examined whether speech intelligibility in noise can be improved using a new, binaural broadband hearing instrument system. Participants were 36 adults with symmetrical, sensorineural hearing loss (18 experienced hearing instrument users and 18 without prior experience). Participants were fit binaurally in a planned comparison, randomized crossover design study with binaural broadband hearing instruments and advanced digital hearing instruments. Following an adjustment period with each device, participants underwent two speech-in-noise tests: the QuickSIN and the Hearing in Noise Test (HINT). Results suggested significantly better performance on the QuickSIN and the HINT measures with the binaural broadband hearing instruments, when compared with the advanced digital hearing instruments and unaided, across and within all noise conditions.

Occupational hearing loss

Science.gov (United States)

... this page: //medlineplus.gov/ency/article/001048.htm Occupational hearing loss To use the sharing features on this page, please enable JavaScript. Occupational hearing loss is damage to the inner ear from noise ...

Dimensions of Deaf/Hard-of Hearing and Hearing Adolescents’ Health Literacy and Health Knowledge

Science.gov (United States)

Smith, Scott R.; Samar, Vincent J.

2016-01-01

Deaf and hard-of-hearing (D/HH) adults have lower health literacy compared to hearing adults but it is unclear if this disparity also occurs in adolescence. We used the Health Literacy Skills Instrument-Short Form (HLSI-SF), Short Form of the Test of Functional Health Literacy (S-TOFHLA), Comprehensive Heart Disease Knowledge Questionnaire (CHDKQ) and newly constructed interactive and critical health literacy survey items to quantify D/HH and hearing adolescents’ health literacy. We adapted and translated survey materials into sign language and spoken English to reduce testing bias due to variable English language skills. Participants were 187 D/HH and 94 hearing college-bound high school students. Adjusting for age, gender, race/ethnicity, school grade, and SES, D/HH adolescents demonstrated weaker general and functional health literacy and cardiovascular health knowledge than hearing adolescents on the HLSI, S-TOFHLA, and CHDKQ (all p’s<.0001). Standard health literacy or knowledge scores were associated with several interactive and critical health literacy skills (all p’s<.05). D/HH adolescents who reported greater hearing-culture identity, having hearing aids, experiencing better hearing with assistive devices, having good quality of communication with parents, and attending hearing schools at least half of the time had higher functional health literacy (all p’s<.025). Those who reported English as their best language and attending hearing schools at least half the time had higher cardiovascular health knowledge scores (all p’s< .03). Results suggest that interventions to improve D/HH adolescents’ health literacy should target their health-related conversations with their families, access to printed health information, and access to health information from other people, especially health care providers and educators. PMID:27548284

Dimensions of Deaf/Hard-of-Hearing and Hearing Adolescents' Health Literacy and Health Knowledge.

Science.gov (United States)

Smith, Scott R; Samar, Vincent J

2016-01-01

Deaf and hard-of-hearing (D/HH) adults have lower health literacy compared to hearing adults, but it is unclear whether this disparity also occurs in adolescence. We used the Health Literacy Skills Instrument-Short Form (HLSI-SF), Short Form of the Test of Functional Health Literacy in Adults (S-TOFHLA), Comprehensive Heart Disease Knowledge Questionnaire (CHDKQ), and newly constructed interactive and critical health literacy survey items to quantify D/HH and hearing adolescents' health literacy. We adapted and translated survey materials into sign language and spoken English to reduce testing bias due to variable English language skills. Participants were 187 D/HH and 94 hearing college-bound high school students. When we adjusted for age, gender, race/ethnicity, school grade, and socioeconomic status, D/HH adolescents demonstrated weaker general and functional health literacy and cardiovascular health knowledge than hearing adolescents on the HLSI, S-TOFHLA, and CHDKQ (all ps < .0001). Standard health literacy or knowledge scores were associated with several interactive and critical health literacy skills (all ps < .05). D/HH adolescents who reported greater hearing-culture identity, having hearing aids, experiencing better hearing with assistive devices, having good quality of communication with parents, and attending hearing schools at least half of the time had higher functional health literacy (all ps < .025). Those who reported English as their best language and attending hearing schools at least half of the time had higher cardiovascular health knowledge scores (all ps < .03). Results suggest that interventions to improve D/HH adolescents' health literacy should target their health-related conversations with their families; access to printed health information; and access to health information from other people, especially health care providers and educators.

Newborn hearing screening programme in Belgium: a consensus recommendation on risk factors.

Science.gov (United States)

Vos, Bénédicte; Senterre, Christelle; Lagasse, Raphaël; Levêque, Alain

2015-10-16

Understanding the risk factors for hearing loss is essential for designing the Belgian newborn hearing screening programme. Accordingly, they needed to be updated in accordance with current scientific knowledge. This study aimed to update the recommendations for the clinical management and follow-up of newborns with neonatal risk factors of hearing loss for the newborn screening programme in Belgium. A literature review was performed, and the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system assessment method was used to determine the level of evidence quality and strength of the recommendation for each risk factor. The state of scientific knowledge, levels of evidence quality, and graded recommendations were subsequently assessed using a three-round Delphi consensus process (two online questionnaires and one face-to-face meeting). Congenital infections (i.e., cytomegalovirus, toxoplasmosis, and syphilis), a family history of hearing loss, consanguinity in (grand)parents, malformation syndromes, and foetal alcohol syndrome presented a 'high' level of evidence quality as neonatal risk factors for hearing loss. Because of the sensitivity of auditory function to bilirubin toxicity, hyperbilirubinaemia was assessed at a 'moderate' level of evidence quality. In contrast, a very low birth weight, low Apgar score, and hospitalisation in the neonatal intensive care unit ranged from 'very low' to 'low' levels, and ototoxic drugs were evidenced as 'very low'. Possible explanations for these 'very low' and 'low' levels include the improved management of these health conditions or treatments, and methodological weaknesses such as confounding effects, which make it difficult to conclude on individual risk factors. In the recommendation statements, the experts emphasised avoiding unidentified neonatal hearing loss and opted to include risk factors for hearing loss even in cases with weak evidence. The panel also highlighted the cumulative effect

Speak on time! Effects of a musical rhythmic training on children with hearing loss.

Science.gov (United States)

Hidalgo, Céline; Falk, Simone; Schön, Daniele

2017-08-01

This study investigates temporal adaptation in speech interaction in children with normal hearing and in children with cochlear implants (CIs) and/or hearing aids (HAs). We also address the question of whether musical rhythmic training can improve these skills in children with hearing loss (HL). Children named pictures presented on the screen in alternation with a virtual partner. Alternation rate (fast or slow) and the temporal predictability (match vs mismatch of stress occurrences) were manipulated. One group of children with normal hearing (NH) and one with HL were tested. The latter group was tested twice: once after 30 min of speech therapy and once after 30 min of musical rhythmic training. Both groups of children (NH and with HL) can adjust their speech production to the rate of alternation of the virtual partner. Moreover, while children with normal hearing benefit from the temporal regularity of stress occurrences, children with HL become sensitive to this manipulation only after rhythmic training. Rhythmic training may help children with HL to structure the temporal flow of their verbal interactions. Copyright © 2017 Elsevier B.V. All rights reserved.

9 CFR 124.42 - Hearing procedure.

Science.gov (United States)

2010-01-01

... Diligence Hearing § 124.42 Hearing procedure. (a) The presiding officer shall be appointed by the... hearing. (g) The due diligence hearing will be conducted in accordance with rules of practice adopted for... opportunity to participate as a party in the hearing. The standard of due diligence set forth in § 124.33 will...

Early Radiosurgery Improves Hearing Preservation in Vestibular Schwannoma Patients With Normal Hearing at the Time of Diagnosis

Energy Technology Data Exchange (ETDEWEB)

Akpinar, Berkcan [University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania (United States); Mousavi, Seyed H., E-mail: mousavish@upmc.edu [Department of Neurological Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania (United States); McDowell, Michael M.; Niranjan, Ajay; Faraji, Amir H. [Department of Neurological Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania (United States); Flickinger, John C. [Department of Radiation Oncology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania (United States); Lunsford, L. Dade [Department of Neurological Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania (United States)

2016-06-01

Purpose: Vestibular schwannomas (VS) are increasingly diagnosed in patients with normal hearing because of advances in magnetic resonance imaging. We sought to evaluate whether stereotactic radiosurgery (SRS) performed earlier after diagnosis improved long-term hearing preservation in this population. Methods and Materials: We queried our quality assessment registry and found the records of 1134 acoustic neuroma patients who underwent SRS during a 15-year period (1997-2011). We identified 88 patients who had VS but normal hearing with no subjective hearing loss at the time of diagnosis. All patients were Gardner-Robertson (GR) class I at the time of SRS. Fifty-seven patients underwent early (≤2 years from diagnosis) SRS and 31 patients underwent late (>2 years after diagnosis) SRS. At a median follow-up time of 75 months, we evaluated patient outcomes. Results: Tumor control rates (decreased or stable in size) were similar in the early (95%) and late (90%) treatment groups (P=.73). Patients in the early treatment group retained serviceable (GR class I/II) hearing and normal (GR class I) hearing longer than did patients in the late treatment group (serviceable hearing, P=.006; normal hearing, P<.0001, respectively). At 5 years after SRS, an estimated 88% of the early treatment group retained serviceable hearing and 77% retained normal hearing, compared with 55% with serviceable hearing and 33% with normal hearing in the late treatment group. Conclusions: SRS within 2 years after diagnosis of VS in normal hearing patients resulted in improved retention of all hearing measures compared with later SRS.

Early Radiosurgery Improves Hearing Preservation in Vestibular Schwannoma Patients With Normal Hearing at the Time of Diagnosis

International Nuclear Information System (INIS)

Akpinar, Berkcan; Mousavi, Seyed H.; McDowell, Michael M.; Niranjan, Ajay; Faraji, Amir H.; Flickinger, John C.; Lunsford, L. Dade

2016-01-01

Purpose: Vestibular schwannomas (VS) are increasingly diagnosed in patients with normal hearing because of advances in magnetic resonance imaging. We sought to evaluate whether stereotactic radiosurgery (SRS) performed earlier after diagnosis improved long-term hearing preservation in this population. Methods and Materials: We queried our quality assessment registry and found the records of 1134 acoustic neuroma patients who underwent SRS during a 15-year period (1997-2011). We identified 88 patients who had VS but normal hearing with no subjective hearing loss at the time of diagnosis. All patients were Gardner-Robertson (GR) class I at the time of SRS. Fifty-seven patients underwent early (≤2 years from diagnosis) SRS and 31 patients underwent late (>2 years after diagnosis) SRS. At a median follow-up time of 75 months, we evaluated patient outcomes. Results: Tumor control rates (decreased or stable in size) were similar in the early (95%) and late (90%) treatment groups (P=.73). Patients in the early treatment group retained serviceable (GR class I/II) hearing and normal (GR class I) hearing longer than did patients in the late treatment group (serviceable hearing, P=.006; normal hearing, P<.0001, respectively). At 5 years after SRS, an estimated 88% of the early treatment group retained serviceable hearing and 77% retained normal hearing, compared with 55% with serviceable hearing and 33% with normal hearing in the late treatment group. Conclusions: SRS within 2 years after diagnosis of VS in normal hearing patients resulted in improved retention of all hearing measures compared with later SRS.

Asymmetric hearing loss in a random population of patients with mild to moderate sensorineural hearing loss.

Science.gov (United States)

Segal, Nili; Shkolnik, Mark; Kochba, Anat; Segal, Avichai; Kraus, Mordechai

2007-01-01

We evaluated the correlation of asymmetric hearing loss, in a random population of patients with mild to moderate sensorineural hearing loss, to several clinical factors such as age, sex, handedness, and noise exposure. We randomly selected, from 8 hearing institutes in Israel, 429 patients with sensorineural hearing loss of at least 30 dB at one frequency and a speech reception threshold not exceeding 30 dB. Patients with middle ear disease or retrocochlear disorders were excluded. The results of audiometric examinations were compared binaurally and in relation to the selected factors. The left ear's hearing threshold level was significantly higher than that of the right ear at all frequencies except 1.0 kHz (p < .05). One hundred fifty patients (35%) had asymmetric hearing loss (more than 10 dB difference between ears). In most of the patients (85%) the binaural difference in hearing threshold level, at any frequency, was less than 20 dB. Age, handedness, and sex were not found to be correlated to asymmetric hearing loss. Noise exposure was found to be correlated to asymmetric hearing loss.

Hearing Loss: Issues in the Deaf and Hard of Hearing Communities.

Science.gov (United States)

Moreland, Christopher; Atcherson, Samuel R; Zazove, Philip; McKee, Michael M

2015-07-01

Hearing loss can lead to impairments in language and speech acquisition, educational attainment, social development, and reading achievement. More than 90% of deaf and hard of hearing (DHH) children are born to hearing parents who may lack the knowledge or experience to effectively care for a child with hearing loss. Family involvement is crucial for teaching self-advocacy and global communication skills, optimizing social development, and helping DHH individuals understand and manage external attitudes about deafness and hearing loss. American Sign Language is a naturally developed language with an always-expanding lexicon and grammatical structures different from those of English. Teaching spoken English and American Sign Language equally, often called bilingual bimodal education, can enhance academic and reading achievement as well as language and psychosocial development. Formal schooling options for a DHH child include enrollment in a public or private school system (often called inclusion, integration, or mainstreaming), a school for the deaf, or a bilingual school. Individuals with hearing loss experience stereotypes and biases that create disparities in health insurance coverage, health care access, and outcomes of mental and physical conditions. Family physicians should recognize and minimize biases to improve health care in the DHH community. Written permission from the American Academy of Family Physicians is required for reproduction of this material in whole or in part in any form or medium.

Apps for Hearing Science and Care.

Science.gov (United States)

Paglialonga, Alessia; Tognola, Gabriella; Pinciroli, Francesco

2015-09-01

Our research aims at the identification and assessment of applications (referred to as apps) in the hearing health care domain. This research forum article presents an overview of the current availability, affordability, and variety of hearing-related apps. The available apps were reviewed by searching on the leading platforms (iOS, Android, Windows Phone stores) using the keywords hearing, audiology, audio, auditory, speech, language, tinnitus, hearing loss, hearing aid, hearing sys tem, cochlear implant, implantable device, auditory training, hearing rehabilitation, and assistive technology/tool/device. O n the bas is of the offered services, apps were classified into 4 application domains: (a) screening and assessment, (b) intervention and rehabilitation, (c) education and information, and (d) assistive tools. A large variety of apps are available in the hearing health care domain. These cover a wide range of services for people with hearing or communication problems as well as for hearing professionals, families, or informal caregivers. This evolution can potentially bring along considerable advantages and improved outcomes in the field of hearing health care. Nevertheless, potential risks and threats (e.g., safety, quality, effectiveness, privacy, and regulation) should not be overlooked. Significant research—particularly in terms of assessment and guidance—is still needed for the informed, aware, and safe adoption of hearing-related apps by patients and professionals.

Effects of Varying Reverberation on Music Perception for Young Normal-Hearing and Old Hearing-Impaired Listeners.

Science.gov (United States)

Reinhart, Paul N; Souza, Pamela E

2018-01-01

Reverberation enhances music perception and is one of the most important acoustic factors in auditorium design. However, previous research on reverberant music perception has focused on young normal-hearing (YNH) listeners. Old hearing-impaired (OHI) listeners have degraded spatial auditory processing; therefore, they may perceive reverberant music differently. Two experiments were conducted examining the effects of varying reverberation on music perception for YNH and OHI listeners. Experiment 1 examined whether YNH listeners and OHI listeners prefer different amounts of reverberation for classical music listening. Symphonic excerpts were processed at a range of reverberation times using a point-source simulation. Listeners performed a paired-comparisons task in which they heard two excerpts with different reverberation times, and they indicated which they preferred. The YNH group preferred a reverberation time of 2.5 s; however, the OHI group did not demonstrate any significant preference. Experiment 2 examined whether OHI listeners are less sensitive to (e, less able to discriminate) differences in reverberation time than YNH listeners. YNH and OHI participants listened to pairs of music excerpts and indicated whether they perceived the same or different amount of reverberation. Results indicated that the ability of both groups to detect differences in reverberation time improved with increasing reverberation time difference. However, discrimination was poorer for the OHI group than for the YNH group. This suggests that OHI listeners are less sensitive to differences in reverberation when listening to music than YNH listeners, which might explain the lack of group reverberation time preferences of the OHI group.

Sensorineural hearing loss in children.

LENUS (Irish Health Repository)

Wormald, R

2010-02-01

The objective of the study was to examine the aetiology of sensorineural hearing loss (SNHL) in a paediatric population presenting to the National Centre of Medical Genetics. A retrospective chart review from 1998 to 2006. One hundred and twenty nine children were investigated for SNHL. The average age of diagnosis of hearing loss was 36 months. The degree of hearing loss was mild in 8 children, moderate in 33 children, severe in 31 children and profound in 57 children. Eighty-five children (66%) were diagnosed with a hereditary hearing loss, 11 (8%) children had an acquired hearing loss and no cause found in 33 (26%) children. This is the first report of the causes of hearing loss in Irish children. The mean age of diagnosis in our cohort is high and emphasises the need for a neonatal screening programme. There remains a number of children for whom the cause of hearing loss remains unknown.

Do You Need a Hearing Test?

Science.gov (United States)

... hearing them? Yes No Do you have difficulty hearing or understanding co-workers, clients, or customers? Yes No Do you feel restricted or limited by a hearing problem? Yes No Do you have difficulty hearing ...

Acoustic Trauma - Hearing Loss in Teenagers

Science.gov (United States)

... I Can Hear It, It's Too Loud: Earbuds & Teen Hearing Loss Page Content ​Many parents will agree ... hearing loss." Recommended Hearing Screenings for Older Children & Teens Kids should be screened at three ages: 11- ...

Hearing Aids: MedlinePlus Health Topic

Science.gov (United States)

... for hearing loss (Medical Encyclopedia) Also in Spanish Topic Image MedlinePlus Email Updates Get Hearing Aids updates ... MEDICAL ENCYCLOPEDIA Devices for hearing loss Related Health Topics Cochlear Implants Hearing Disorders and Deafness National Institutes ...

Age-related Hearing Impairment and the Triad of Acquired Hearing Loss

Directory of Open Access Journals (Sweden)

Chao-Hui eYang

2015-07-01

Full Text Available Understanding underlying pathological mechanisms is prerequisite for a sensible design of protective therapies against hearing loss. The triad of age-related, noise-generated, and drug-induced hearing loss ¬¬displays intriguing similarities in some cellular responses of cochlear sensory cells such as a potential involvement of reactive oxygen species and apoptotic and necrotic cell death. On the other hand, detailed studies have revealed that molecular pathways are considerably complex and, importantly, it has become clear that pharmacological protection successful against one form of hearing loss will not necessarily protect against another. This review will summarize pathological and pathophysiological features of age-related hearing impairment (ARHI in human and animal models and address selected aspects of the commonality (or lack thereof of cellular responses in ARHI to drugs and noise.

Hearing Conservation Live #2430

Energy Technology Data Exchange (ETDEWEB)

Chochoms, Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2016-08-09

Occupational hearing loss is one of the most common work-related illnesses in the United States (US). From 22 to 30 million US workers are exposed to hazardous noise levels at work, and 25% of these workers will develop permanent hearing loss. Hearing loss from noise is slow and painless, and you can have a disability before you notice it. This course presents the hazards associated with workplace noise, the purpose and elements of the Los Alamos National Laboratory (LANL) Hearing Conservation Program (HCP), and controls that are available to reduce your exposure to hazardous levels of noise.

Vestibular (dys)function in children with sensorineural hearing loss: a systematic review.

Science.gov (United States)

Verbecque, Evi; Marijnissen, Tessa; De Belder, Niels; Van Rompaey, Vincent; Boudewyns, An; Van de Heyning, Paul; Vereeck, Luc; Hallemans, Ann

2017-06-01

The objective of this study is to provide an overview of the prevalence of vestibular dysfunction in children with SNHL classified according to the applied test and its corresponding sensitivity and specificity. Data were gathered using a systematic search query including reference screening. Pubmed, Web of Science and Embase were searched. Strategy and reporting of this review was based on the Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines. Methodological quality was assessed with the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklist. All studies, regardless the applied vestibular test, showed that vestibular function differs significantly between children with hearing loss and normal hearing (p 30).

Ear malformations, hearing loss and hearing rehabilitation in children with Treacher Collins syndrome.

Science.gov (United States)

Rosa, Francisco; Coutinho, Miguel Bebiano; Ferreira, João Pinto; Sousa, Cecilia Almeida

2016-01-01

The aim of this study was to assess the main ear malformations, hearing loss and auditory rehabilitation in children with Treacher Collins syndrome. We performed a retrospective study of 9 children with Treacher Collins syndrome treated in a central hospital between January 2003 and January 2013. This study showed a high incidence of malformations of the outer and middle ear, such as microtia, atresia or stenosis of the external auditory canal, hypoplastic middle ear cavity, dysmorphic or missing ossicular chain. Most patients had bilateral hearing loss of moderate or high degree. In the individuals studied, there was functional improvement in patients with bone-anchored hearing aids in relation to conventional hearing aids by bone conduction. Treacher Collins syndrome is characterized by bilateral malformations of the outer and middle ear. Hearing rehabilitation in these children is of utmost importance, and bone-anchored hearing aids is the method of choice. Copyright © 2014 Elsevier España, S.L.U. y Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello. All rights reserved.

Decline of Low-Frequency Hearing in People With Ski-Slope Hearing Loss; Implications for Electrode Array Insertion.

Science.gov (United States)

Schuurbiers, Jasper; Dingemanse, Gertjan; Metselaar, Mick

2017-12-01

The decline of low-frequency hearing in people with ski-slope hearing loss varies and might depend on etiology. People with ski-sloping hearing loss might benefit from cochlear implantation with preservation of residual hearing. To reduce the risk of losing low-frequency hearing after implantation, the electrode-array can be inserted partially up to the desired frequency. That, however, obstructs electrical stimulation of lower frequencies. To decide between complete or partial insertion, knowledge regarding the natural decline of low-frequency hearing is helpful. Patients with at least two ski-slope audiograms over time were selected. We calculated progression at lower frequencies for 320 patients. Etiologies for hearing loss were retrieved from medical records. Progression of hearing loss was analyzed separately for patients with uni- and bilateral hearing losses. Relative progression of hearing loss was obtained by comparing progression to a reference group. Average progression of PTA was 1.73 dB/yr and was not significantly different in the bilateral and unilateral group. Etiologies that did not show significantly more progression compared with the reference group could be identified as single or short-lasting pathologic events, whereas long-lasting conditions had significant more progression of PTA. Patients with a ski-slope hearing loss that was caused by a single or short-lasting event have low progression rate and are viable for partial insertion to minimize the risk of damaging residual low-frequency hearing. In the absence of such an event, complete insertion should be considered because faster than normal deterioration of low-frequency hearing over time will probably limit the advantage of preservation of residual hearing.

Hearing Aid Personalization

DEFF Research Database (Denmark)

Nielsen, Jens Brehm; Nielsen, Jakob; Jensen, Bjørn Sand

2013-01-01

Modern digital hearing aids require and offer a great level of personalization. Today, this personalization is not performed based directly on what the user actually perceives, but on a hearing-care professional’s interpretation of what the user explains about what is perceived. In this paper......, an interactive personalization system based on Gaussian process regression and active learning is proposed, which personalize the hearing aids based directly on what the user perceives. Preliminary results demonstrate a significant difference between a truly personalized setting obtained with the proposed system...

Hearing poorly with skill

DEFF Research Database (Denmark)

Day, Dennis

2012-01-01

This paper offers an account of ongoing research into hearing. I offer a characterization of 'skil- led practitioners' from an Ethnomethodological perspective. The skilled practitioner in question is a generic 'hard of hearing' person. The ambition is that such a characterization, both in its...... making and its final state, may be an intrinsic part of design practices concerning the development of hearing aids....

Hearing aid controlled by binaural source localizer

NARCIS (Netherlands)

2009-01-01

An adaptive directional hearing aid system comprising a left hearing aid and a right hearing aid, wherein a binaural acoustic source localizer is located in the left hearing aid or in the right hearing aid or in a separate body- worn device connected wirelessly to the left hearing aid and the right

Analysis of risk factors associated with unilateral hearing loss in children who initially passed newborn hearing screening.

Science.gov (United States)

Appelbaum, Eric N; Howell, Jessica B; Chapman, Derek; Pandya, Arti; Dodson, Kelley M

2018-03-01

To analyze 2007 Joint Committee on Infant Hearing (JCIH) risk factors in children with confirmed unilateral hearing loss (UHL) who initially passed newborn hearing screening. Retrospective record review of 16,108 infants who passed newborn hearing screening but had one or more JCIH risk factors prompting subsequent follow-up through the universal newborn hearing screening (UNHS) program in Virginia from 2010 to 2012. The study was reviewed and qualified as exempt by the Virginia Commonwealth University Institutional Review Board (IRB) and the Virginia Department of Health. Over the 2-year study period, 14896 (4.9% of total births) children passed UNHS but had the presence of one or more JCIH risk factor. Ultimately, we identified 121 babies from this group with confirmed hearing loss (0.7%), with 48 babies (0.2%) showing UHL. The most common risk factors associated with the development of confirmed UHL after passing the initial screen were neonatal indicators, craniofacial anomalies, family history, and stigmata of syndrome associated with hearing loss. Neonatal indicators and craniofacial anomalies were the categories most often found in children with confirmed unilateral hearing loss who initially passed their newborn hearing screen. While neonatal indicators were also the most common associated risk factor in all hearing loss, craniofacial abnormalities are relatively more common in children with UHL who initially passed newborn hearing screening. Further studies assessing the etiology underlying the hearing loss and risk factor associations are warranted. Copyright © 2018 Elsevier B.V. All rights reserved.

78 FR 56951 - Notice of Hearing

Science.gov (United States)

2013-09-16

... No. 6] Notice of Hearing ACTION: Notice of a hearing. SUMMARY: The Privacy and Civil Liberties Oversight Board (PCLOB) will conduct a public hearing with current and former government officials and... federal government regarding the government's counterterrorism surveillance programs. This hearing will...

A new captorhinid reptile from the Lower Permian of Oklahoma showing remarkable dental and mandibular convergence with microsaurian tetrapods

Science.gov (United States)

Reisz, R. R.; LeBlanc, Aaron R. H.; Sidor, Christian A.; Scott, Diane; May, William

2015-10-01

The Lower Permian fossiliferous infills of the Dolese Brothers Limestone Quarry, near Richards Spur, Oklahoma, have preserved the most diverse assemblage of Paleozoic terrestrial vertebrates, including small-bodied reptiles and lepospondyl anamniotes. Many of these taxa were previously known only from fragmentary remains, predominantly dentigerous jaw elements and numerous isolated skeletal elements. The recent discovery of articulated skulls and skeletons of small reptiles permits the recognition that dentigerous elements, previously assigned at this locality to the anamniote lepospondyl Euryodus primus, belong to a new captorhinid eureptile, Opisthodontosaurus carrolli gen. et sp. nov. This mistaken identity points to a dramatic level of convergence in mandibular and dental anatomy in two distantly related and disparate clades of terrestrial tetrapods and sheds light on the earliest instance of durophagy in eureptiles.

Improvements in Speech Understanding With Wireless Binaural Broadband Digital Hearing Instruments in Adults With Sensorineural Hearing Loss

OpenAIRE

Kreisman, Brian M.; Mazevski, Annette G.; Schum, Donald J.; Sockalingam, Ravichandran

2010-01-01

This investigation examined whether speech intelligibility in noise can be improved using a new, binaural broadband hearing instrument system. Participants were 36 adults with symmetrical, sensorineural hearing loss (18 experienced hearing instrument users and 18 without prior experience). Participants were fit binaurally in a planned comparison, randomized crossover design study with binaural broadband hearing instruments and advanced digital hearing instruments. Following an adjustment peri...

PSYCHOSOCIAL INFLUENCE OF HEARING IMPAIRMENT ON THE INTERPERSONAL BEHAVIOR OF YOUTHS WITH HEARING IMPAIRMENT IN OYO STATE, NIGERIA

Directory of Open Access Journals (Sweden)

Osisanya AYO

2013-03-01

Full Text Available Individuals with hearing impairment are confronted with a lot of problems due to the condition of their disability. This has a negative impact on their social and psychological well-being with multiplying effect on their interpersonal relationship. Therefore, this study investigated the psycho-social influence of hearing impairment on interpersonal behavior of youths with hearing loss.MethodologyThe study adopted a survey research design. A sample consisting of 211 participants with hearing loss were purposively selected from the Federal College of Education (Special Oyo, Nigeria. A questionnaire, part of Psycho-social Competence Scale (PCS, was used for data collection with reliability coefficient of 0.72.ResultsThe findings revealed that hearing impairement affects social interaction of youths with hearing impairment, hearing loss affects emotional well-being of youths with hearing impairment and youths with hearing impairment feel inferior in company of persons without hearing impairment. Based on this, it was recommended that a friendly home environment should be made and youths with hearing impairment should be advised to accept their loss and take it as a challenge that can be used to achieve a better end and the society should have right attitude and beliefs toward youths with hearing impairment.

Hearing Status in Pediatric Renal Transplant Recipients.

Science.gov (United States)

Gulleroglu, Kaan; Baskin, Esra; Aydin, Erdinc; Ozluoglu, Levent; Moray, Gokhan; Haberal, Mehmet

2015-08-01

Renal transplant provides a long-term survival. Hearing impairment is a major factor in subjective health status. Status of hearing and the cause of hearing impairment in the pediatric renal transplant group have not been evaluated. Here, we studied to evaluate hearing status in pediatric renal transplant patients and to determine the factors that cause hearing impairment. Twenty-seven pediatric renal transplant recipients were investigated. All patients underwent audiologic assessment by means of pure-tone audiometry. The factors on hearing impairment were performed. Sensorineural hearing impairment was found in 17 patients. There was marked hearing impairment for the higher frequencies between 4000 and 8000 Hz. Sudden hearing loss developed in 2 patients, 1 of them had tinnitus. Decrease of speech understanding was found in 8 patients. The cyclosporine level was significantly high in patients with hearing impairment compared with group without hearing impairment. Cyclosporine levels also were found to be statistically significantly high when compared with the group with decrease of speech understanding and the group without decrease of speech understanding. Similar relations cannot be found between tacrolimus levels and hearing impairment and speech understanding. Sensorineural hearing impairment prevalence was high in pediatric renal transplant recipients when compared with the general population of children. Cyclosporine may be responsible for causing hearing impairment after renal transplant. We suggest that this effect is a dose-dependent toxicity.

Comparison of Different Levels of Reading Comprehension between Hearing-Impaired Loss and Normal-Hearing Students

Directory of Open Access Journals (Sweden)

Azam Sharifi

2011-12-01

Full Text Available Background and Aim: Reading skill is one of the most important necessities of students' learning in everyday life. This skill is referred to the ability of comprehension, comment and conclusion from texts and receiving the meaning of the massage which is composed. Educational development in any student has a direct relation with the ability of the comprehension. This study is designed to investigate the effects of hearing loss on reading comprehension in hearing-impaired students compared to normal-hearing ones.Methods: Seventeen hearing-impaired students in 4th year of primary exceptional schools in Karaj, Robatkarim and Shahriyar, Iran, were enrolled in this cross-sectional study. Seventeen normal-hearing students were randomly selected from ordinary schools next to exceptional ones as control group. They were compared for different levels of reading comprehension using the international standard booklet (PIRLS 2001. Results: There was a significant difference in performance between hearing-impaired and normal- hearing students in different levels of reading comprehension (p<0.05.Conclusion: Hearing loss has negative effects on different levels of reading comprehension, so in exceptional centers, reconsideration in educational planning in order to direct education from memorizing to comprehension and deeper layers of learning seems necessary.

Cranial muscle development in the model organism ambystoma mexicanum: implications for tetrapod and vertebrate comparative and evolutionary morphology and notes on ontogeny and phylogeny.

Science.gov (United States)

Ziermann, Janine M; Diogo, Rui

2013-07-01

There is still confusion about the homology of several cranial muscles in salamanders with those of other vertebrates. This is true, in part, because of the fact that many muscles present in early ontogeny of amphibians disappear during development and specifically during metamorphosis. Resolving this confusion is important for the understanding of the comparative and evolutionary morphology of vertebrates and tetrapods because amphibians are the phylogenetically most plesiomorphic tetrapods, concerning for example their myology, and include two often used model organisms, Xenopus laevis (anuran) and Ambystoma mexicanum (urodele). Here we provide the first detailed report of the cranial muscle development in axolotl from early ontogenetic stages to the adult stage. We describe different and complementary types of general muscle morphogenetic gradients in the head: from anterior to posterior, from lateral to medial, and from origin to insertion. Furthermore, even during the development of neotenic salamanders such as axolotls, various larval muscles become indistinct, contradicting the commonly accepted view that during ontogeny the tendency is mostly toward the differentiation of muscles. We provide an updated comparison between these muscles and the muscles of other vertebrates, a discussion of the homologies and evolution, and show that the order in which the muscles appear during axolotl ontogeny is in general similar to their appearance in phylogeny (e.g. differentiation of adductor mandibulae muscles from one anlage to four muscles), with only a few remarkable exceptions, as for example the dilatator laryngis that appears evolutionary later but in the development before the intermandibularis. Copyright © 2013 Wiley Periodicals, Inc.

Improving hearing health for farming families.

Science.gov (United States)

Lower, Tony; Fragar, Lyn; Depcynzksi, Julie; Challinor, Kathy; Mills, Jan; Williams, Warwick

2010-01-01

Occupational noise injury and hearing loss are common features of agricultural workforces internationally. Farmsafe Australia has identified hearing health as one of its 4 key priority goals and targets. Currently, approximately 60-70% of Australian farmers have measurable hearing loss, compared with 27% of those in the general Australian community. This article describes the findings of a community based demonstration project to address hearing health issues conducted in the Australian state of New South Wales. This program sought to implement local demonstration projects in 3 communities to identify what works well in hearing health promotion with farmers and what could be applied more broadly throughout Australia. Local advisory groups were established in each community to guide project development and implementation. Project implementation focused on 3 major aspects: (1) increasing awareness of priority noise injury prevention and hearing health practices; (2) improving access to hearing health services; and (3) networking services in local communities. Area-specific training was undertaken for stakeholders to maximize local information links. Service utilization data were monitored and analysed. There was variability among sites; however in general there was an increased awareness of hearing health issues by farming families and expanded opportunities for farmers to access screening services. Utilization rates of hearing services also increased markedly in one community. Local hearing health networks were strengthened by linkages to key stakeholders outside the health sector. Previously unidentified methods of promoting hearing health (eg using agricultural retail outlets that supply hearing protection equipment and are accepted by farmers as an information source) were identified and utilized. Hearing health promotion with farmers in local communities can be enhanced through utilization and strengthening of local networks. Integration of hearing health

Safety limit warning levels for the avoidance of excessive sound amplification to protect against further hearing loss.

Science.gov (United States)

Johnson, Earl E

2017-11-01

To determine safe output sound pressure levels (SPL) for sound amplification devices to preserve hearing sensitivity after usage. A mathematical model consisting of the Modified Power Law (MPL) (Humes & Jesteadt, 1991 ) combined with equations for predicting temporary threshold shift (TTS) and subsequent permanent threshold shift (PTS) (Macrae, 1994b ) was used to determine safe output SPL. The study involves no new human subject measurements of loudness tolerance or threshold shifts. PTS was determined by the MPL model for 234 audiograms and the SPL output recommended by four different validated prescription recommendations for hearing aids. PTS can, on rare occasion, occur as a result of SPL delivered by hearing aids at modern day prescription recommendations. The trading relationship of safe output SPL, decibel hearing level (dB HL) threshold, and PTS was captured with algebraic expressions. Better hearing thresholds lowered the safe output SPL and higher thresholds raised the safe output SPL. Safe output SPL can consider the magnitude of unaided hearing loss. For devices not set to prescriptive levels, limiting the output SPL below the safe levels identified should protect against threshold worsening as a result of long-term usage.

Newborn hearing screening.

Science.gov (United States)

Stewart, D L; Pearlman, A

1994-11-01

Congenital deafness is a relatively common problem with an incidence of 1/300 to 1/1000. Most states have no mass screening program for hearing loss, but the state of Kentucky compiles a High Risk Registry which is a historical survey of parents relating to risk factors for hearing loss. Unfortunately this survey can miss 50% of those who have a hearing deficit. If not detected prior to discharge, there is often a delay in diagnosis of deafness which prevents early intervention. We report 2 years' experience at Kosair Children's Hospital where 1,987 infants admitted to well baby, intermediate, or intensive care nurseries were screened using the ALGO-1 screener (Natus Medical Inc, Foster City, CA) which is a modified auditory brain stem evoked response (ABR). Our screening of this population led to an 11% incidence of referral for complete audiological evaluation. There were no significant complications. Forty-eight infants were found to have nonspecified, sensorineural, or conductive hearing loss. The positive predictive value of the test was 96%. Therefore, we feel that the use of the modified ABR in the newborn is a timely, cost efficient method of screening for hearing loss and should be used for mass screening of all newborns.

40 CFR 791.30 - Hearing procedures.

Science.gov (United States)

2010-07-01

... officer may deem necessary to an understanding and determination of the dispute. The hearing officer shall... 40 Protection of Environment 31 2010-07-01 2010-07-01 true Hearing procedures. 791.30 Section 791... (CONTINUED) DATA REIMBURSEMENT Hearing Procedures § 791.30 Hearing procedures. (a) Representation by counsel...

Sensorineural hearing loss degrades behavioral and physiological measures of human spatial selective auditory attention

Science.gov (United States)

Dai, Lengshi; Best, Virginia; Shinn-Cunningham, Barbara G.

2018-01-01

Listeners with sensorineural hearing loss often have trouble understanding speech amid other voices. While poor spatial hearing is often implicated, direct evidence is weak; moreover, studies suggest that reduced audibility and degraded spectrotemporal coding may explain such problems. We hypothesized that poor spatial acuity leads to difficulty deploying selective attention, which normally filters out distracting sounds. In listeners with normal hearing, selective attention causes changes in the neural responses evoked by competing sounds, which can be used to quantify the effectiveness of attentional control. Here, we used behavior and electroencephalography to explore whether control of selective auditory attention is degraded in hearing-impaired (HI) listeners. Normal-hearing (NH) and HI listeners identified a simple melody presented simultaneously with two competing melodies, each simulated from different lateral angles. We quantified performance and attentional modulation of cortical responses evoked by these competing streams. Compared with NH listeners, HI listeners had poorer sensitivity to spatial cues, performed more poorly on the selective attention task, and showed less robust attentional modulation of cortical responses. Moreover, across NH and HI individuals, these measures were correlated. While both groups showed cortical suppression of distracting streams, this modulation was weaker in HI listeners, especially when attending to a target at midline, surrounded by competing streams. These findings suggest that hearing loss interferes with the ability to filter out sound sources based on location, contributing to communication difficulties in social situations. These findings also have implications for technologies aiming to use neural signals to guide hearing aid processing. PMID:29555752

Preferred Compression Speed for Speech and Music and Its Relationship to Sensitivity to Temporal Fine Structure

OpenAIRE

Moore, Brian C. J.; S?k, Aleksander

2016-01-01

Multichannel amplitude compression is widely used in hearing aids. The preferred compression speed varies across individuals. Moore (2008) suggested that reduced sensitivity to temporal fine structure (TFS) may be associated with preference for slow compression. This idea was tested using a simulated hearing aid. It was also assessed whether preferences for compression speed depend on the type of stimulus: speech or music. Twenty-two hearing-impaired subjects were tested, and the stimulated h...

Hearing Preservation in Cochlear Implant Surgery

Directory of Open Access Journals (Sweden)

Priscila Carvalho Miranda

2014-01-01

Full Text Available In the past, it was thought that hearing loss patients with residual low-frequency hearing would not be good candidates for cochlear implantation since insertion was expected to induce inner ear trauma. Recent advances in electrode design and surgical techniques have made the preservation of residual low-frequency hearing achievable and desirable. The importance of preserving residual low-frequency hearing cannot be underestimated in light of the added benefit of hearing in noisy atmospheres and in music quality. The concept of electrical and acoustic stimulation involves electrically stimulating the nonfunctional, high-frequency region of the cochlea with a cochlear implant and applying a hearing aid in the low-frequency range. The principle of preserving low-frequency hearing by a “soft surgery” cochlear implantation could also be useful to the population of children who might profit from regenerative hair cell therapy in the future. Main aspects of low-frequency hearing preservation surgery are discussed in this review: its brief history, electrode design, principles and advantages of electric-acoustic stimulation, surgical technique, and further implications of this new treatment possibility for hearing impaired patients.

78 FR 11237 - Public Hearing

Science.gov (United States)

2013-02-15

... NATIONAL TRANSPORTATION SAFETY BOARD Public Hearing On Tuesday, February 26, 2013 the National Transportation Safety Board (NTSB) will convene an Investigative Hearing to gather additional factual information... Union Pacific (UP) intermodal train No. AAMMLX-22 on June 24, 2012 near Goodwell, Oklahoma. The hearing...

Efficient evaluation of hearing ability

NARCIS (Netherlands)

2010-01-01

The present invention relates to a method of establishing a hearing ability model for a person, the method including providing a representation of the distribution of hearing ability for a population of individuals. The method may comprise the steps) performing a hearing evaluation event, comprising

78 FR 39017 - Investigative Hearing

Science.gov (United States)

2013-06-28

... NATIONAL TRANSPORTATION SAFETY BOARD Investigative Hearing On November 30, 2012, at 6:59 a.m... exposure. The investigative hearing will discuss Conrail operations and the emergency response to the... in establishing a unified command. The goals of this hearing are to gather additional factual...

78 FR 64026 - Investigative Hearing

Science.gov (United States)

2013-10-25

... NATIONAL TRANSPORTATION SAFETY BOARD Investigative Hearing On Wednesday, November 6, 2013, and... hearing to gather additional factual information for the ongoing investigation into two Metro-North... Investigative Hearing. On Friday, May 17, 2013, at 6:01 p.m. eastern daylight time, eastbound Metro-North...

Hereditary Hearing Loss.

Science.gov (United States)

Tran, LenhAnh P.; Grundfast, Kenneth M.

1997-01-01

This article discusses inheritance patterns in hearing loss, epidemiology, clues to genetic causes, locating genes that cause hereditary disorders, genes related to hearing loss disorders in individuals with Usher syndrome, Waardenburg syndrome, Treacher-Collins syndrome, Branchio-oto-renal and Pendred syndromes, and the significance of finding…

Peer Victimization Experienced by Children and Adolescents Who Are Deaf or Hard of Hearing

Science.gov (United States)

Kouwenberg, Maartje; Rieffe, Carolien; Theunissen, Stephanie C. P. M.; de Rooij, Mark

2012-01-01

Victimization is a relatively common, yet serious problem, with potentially severe consequences for children's psychosocial and academic functioning. Children who are Deaf or Hard of Hearing (DHH) may be at a higher risk for victimization than hearing children. The aims of the present study were to compare DHH and hearing children on i) self-reported experiences of victimization and ii) associations between victimization, parental- and child variables. In total 188 children (mean age 11;11 years) from the Netherlands and Dutch-speaking part of Belgium participated in the study. No difference between DHH and hearing children were found on general experiences of victimization. However, differences between the groups were found on specific forms of experienced victimization and on the associations between victimization and parental variables. For DHH children, parental sensitivity and parents who challenge their DHH children to become competent in the practical, emotional, cognitive and social domain is associated with them being less victimized. For hearing children at this age these relations were reversed, absent or more complex. Finally, DHH children in special schools were more victimized than DHH children in regular schools. It can be concluded that parents can play an important role in reducing social problems experienced by DHH children and young adolescents. PMID:23284923

Parenting Styles of Mothers with Deaf or Hard-of-Hearing Children and Hearing Siblings

Science.gov (United States)

Antonopoulou, Katerina; Hadjikakou, Kika; Stampoltzis, Aglaia; Nicolaou, Nicoletta

2012-01-01

The present study aims to determine whether rearing a deaf or hard-of-hearing (d/hh) child would differentiate the parenting and disciplinary preference of parents between the d/hh and the hearing child. The parenting styles of 30 hearing mothers from Cyprus were assessed using the Greek version of the Parenting Styles & Dimensions…

The development and standardization of Self-assessment for Hearing Screening of the Elderly

Directory of Open Access Journals (Sweden)

Kim G

2016-06-01

Full Text Available Gibbeum Kim,1 Wondo Na,1 Gungu Kim,1 Woojae Han,2 Jinsook Kim2 1Department of Speech Pathology and Audiology, Hallym University Graduate School, Chuncheon, Republic of Korea; 2Division of Speech Pathology and Audiology, Research Institute of Audiology and Speech Pathology, College of Natural Sciences, Hallym Universtiy, Chuncheon, Republic of Korea Purpose: The present study aimed to develop and standardize a screening tool for elderly people who wish to check for themselves their level of hearing loss. Methods: The Self-assessment for Hearing Screening of the Elderly (SHSE consisted of 20 questions based on the characteristics of presbycusis using a five-point scale: seven questions covered general issues related to sensorineural hearing loss, seven covered hearing difficulty under distracting listening conditions, two covered hearing difficulty with fast-rated speech, and four covered the working memory function during communication. To standardize SHSE, 83 elderly participants took part in the study: 25 with normal hearing, and 22, 23, and 13 with mild, moderate, and moderate-to-severe sensorineural hearing loss, respectively, according to their hearing sensitivity. All were retested 3 weeks later using the same questionnaire to confirm its reliability. In addition, validity was assessed using various hearing tests such as a sentence test with background noise, a time-compressed speech test, and a digit span test. Results: SHSE and its subcategories showed good internal consistency. SHSE and its subcategories demonstrated high test–retest reliability. A high correlation was observed between the total scores and pure-tone thresholds, which indicated gradually increased SHSE scores of 42.24%, 55.27%, 66.61%, and 78.15% for normal hearing, mild, moderate, and moderate-to-severe groups, respectively. With regard to construct validity, SHSE showed a high negative correlation with speech perception scores in noise and a moderate negative

Interactions between Hair Cells Shape Spontaneous Otoacoustic Emissions in a Model of the Tokay Gecko's Cochlea

OpenAIRE

Gelfand, Michael; Piro, Oreste; Magnasco, Marcelo O.; Hudspeth, A. J.

2010-01-01

Background The hearing of tetrapods including humans is enhanced by an active process that amplifies the mechanical inputs associated with sound, sharpens frequency selectivity, and compresses the range of responsiveness. The most striking manifestation of the active process is spontaneous otoacoustic emission, the unprovoked emergence of sound from an ear. Hair cells, the sensory receptors of the inner ear, are known to provide the energy for such emissions; it is unclear, though, how ens...

Descriptive anatomy and three-dimensional reconstruction of the skull of the early tetrapod Acanthostega gunnari Jarvik, 1952.

Science.gov (United States)

Porro, Laura B; Rayfield, Emily J; Clack, Jennifer A

2015-01-01

The early tetrapod Acanthostega gunnari is an iconic fossil taxon exhibiting skeletal morphology reflecting the transition of vertebrates from water onto land. Computed tomography data of two Acanthostega skulls was segmented using visualization software to digitally separate bone from matrix and individual bones of the skull from each other. A revised description of cranial and lower jaw anatomy in this taxon based on CT data includes new details of sutural morphology, the previously undescribed quadrate and articular bones, and the mandibular symphysis. Sutural morphology is used to infer loading regime in the skull during feeding, and suggests Acanthostega used its anterior jaws to initially seize prey while smaller posterior teeth were used to restrain struggling prey during ingestion. Novel methods were used to repair and retrodeform the skull, resulting in a three-dimensional digital reconstruction that features a longer postorbital region and more strongly hooked anterior lower jaw than previous attempts while supporting the presence of a midline gap between the nasals and median rostrals.

Descriptive Anatomy and Three-Dimensional Reconstruction of the Skull of the Early Tetrapod Acanthostega gunnari Jarvik, 1952

Science.gov (United States)

Porro, Laura B.; Rayfield, Emily J.; Clack, Jennifer A.

2015-01-01

The early tetrapod Acanthostega gunnari is an iconic fossil taxon exhibiting skeletal morphology reflecting the transition of vertebrates from water onto land. Computed tomography data of two Acanthostega skulls was segmented using visualization software to digitally separate bone from matrix and individual bones of the skull from each other. A revised description of cranial and lower jaw anatomy in this taxon based on CT data includes new details of sutural morphology, the previously undescribed quadrate and articular bones, and the mandibular symphysis. Sutural morphology is used to infer loading regime in the skull during feeding, and suggests Acanthostega used its anterior jaws to initially seize prey while smaller posterior teeth were used to restrain struggling prey during ingestion. Novel methods were used to repair and retrodeform the skull, resulting in a three-dimensional digital reconstruction that features a longer postorbital region and more strongly hooked anterior lower jaw than previous attempts while supporting the presence of a midline gap between the nasals and median rostrals. PMID:25760343

49 CFR 190.327 - Hearings.

Science.gov (United States)

2010-10-01

... scheduling of a hearing. A petition is granted only if the petitioner shows good cause for a hearing. If a... Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... not provide for a hearing, any interested person may petition the Administrator for an informal...