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OtoRhinoLaryngology by Sfakianakis G.Alexandros Sfakianakis G.Alexandros,Anapafseos 5 Agios Nikolaos 72100 Crete Greece,tel : 00302841026182,00306932607174
This paper presents a theoretical study of sound propagation in a duct with a tube array flush-mounted periodically. The underlying wave interaction is analyzed by the transfer matrix method, and validated by the numerical simulation. With identical tubes, a particular situation is observed that the periodic distance and the tube length are “matched,” leading to a strong coupling effect by Bragg reflection and tube resonance, resulting in a wide stopband in low frequency. Even when the tubes in the array are not identical, the Bragg reflection can still work to broaden the stopband which was originally contributed by tube resonances.
This paper presents a theoretical study of sound propagation in a duct with a tube array flush-mounted periodically. The underlying wave interaction is analyzed by the transfer matrix method, and validated by the numerical simulation. With identical tubes, a particular situation is observed that the periodic distance and the tube length are “matched,” leading to a strong coupling effect by Bragg reflection and tube resonance, resulting in a wide stopband in low frequency. Even when the tubes in the array are not identical, the Bragg reflection can still work to broaden the stopband which was originally contributed by tube resonances.
Mapping the speed of mechanical waves traveling inside a medium is a topic of great interest across many fields from geoscience to medical diagnostics. Much work has been done to characterize the fidelity with which the geometrical features of the medium can be reconstructed and multiple resolution criteria have been proposed depending on the wave-matter interaction model used to decode the wave speed map from scattering measurements. However, these criteria do not define the accuracy with which the wave speed values can be reconstructed. Using two-dimensional simulations, it is shown that the first-arrival traveltime predicted by ray theory can be an accurate representation of the arrival of a pulse first break even in the presence of diffraction and other phenomena that are not accounted for by ray theory. As a result, ray-based tomographic inversions can yield accurate wave speed estimations also when the size of a sound speed anomaly is smaller than the resolution length of the inversion method provided that traveltimes are estimated from the signal first break. This increased sensitivity however renders the inversion more susceptible to noise since the amplitude of the signal around the first break is typically low especially when three-dimensional anomalies are considered.
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Comprehensive Analysis of Deafness Genes in Families with Autosomal Recessive Nonsyndromic Hearing Loss.
PLoS One. 2015;10(11):e0142154
Authors: Atik T, Onay H, Aykut A, Bademci G, Kirazli T, Tekin M, Ozkinay F
Abstract
Comprehensive genetic testing has the potential to become the standard of care for individuals with hearing loss. In this study, we investigated the genetic etiology of autosomal recessive nonsyndromic hearing loss (ARNSHL) in a Turkish cohort including individuals with cochlear implant, who had a pedigree suggestive of an autosomal recessive inheritance. A workflow including prescreening of GJB2 and a targeted next generation sequencing panel (Illumına TruSightTM Exome) covering 2761 genes that we briefly called as mendelian exome sequencing was used. This panel includes 102 deafness genes and a number of genes causing Mendelian disorders. Using this approach, we identified causative variants in 21 of 29 families. Three different GJB2 variants were present in seven families. Remaining 14 families had 15 different variants in other known NSHL genes (MYO7A, MYO15A, MARVELD2, TMIE, DFNB31, LOXHD1, GPSM2, TMC1, USH1G, CDH23). Of these variants, eight are novel. Mutation detection rate of our workflow is 72.4%, confirming the usefulness of targeted sequencing approach in NSHL.
PMID: 26561413 [PubMed - indexed for MEDLINE]
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Whole-exome sequencing identifies USH2A mutations in a pseudo-dominant Usher syndrome family.
Int J Mol Med. 2015 Oct;36(4):1035-41
Authors: Zheng SL, Zhang HL, Lin ZL, Kang QY
Abstract
Usher syndrome (USH) is an autosomal recessive (AR) multi-sensory degenerative disorder leading to deaf-blindness. USH is clinically subdivided into three subclasses, and 10 genes have been identified thus far. Clinical and genetic heterogeneities in USH make a precise diagnosis difficult. A dominant‑like USH family in successive generations was identified, and the present study aimed to determine the genetic predisposition of this family. Whole‑exome sequencing was performed in two affected patients and an unaffected relative. Systematic data were analyzed by bioinformatic analysis to remove the candidate mutations via step‑wise filtering. Direct Sanger sequencing and co‑segregation analysis were performed in the pedigree. One novel and two known mutations in the USH2A gene were identified, and were further confirmed by direct sequencing and co‑segregation analysis. The affected mother carried compound mutations in the USH2A gene, while the unaffected father carried a heterozygous mutation. The present study demonstrates that whole‑exome sequencing is a robust approach for the molecular diagnosis of disorders with high levels of genetic heterogeneity.
PMID: 26310143 [PubMed - indexed for MEDLINE]
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Outcome Measurement in Adult Auditory Rehabilitation: A Scoping Review of Measures Used in Randomized Controlled Trials.
Ear Hear. 2015 Sep-Oct;36(5):567-73
Authors: Barker F, MacKenzie E, Elliott L, de Lusignan S
Abstract
OBJECTIVES: This review documented the range and nature of reported outcome measures in the context of adult auditory rehabilitative research.
DESIGN: A scoping review conducted as a part of the development of a systematic review of the effect of interventions to improve hearing aid use. The authors searched the Cochrane Ear, Nose and Throat Disorders Group Trials Register; the Cochrane Central Register of Controlled Trials; PubMed; EMBASE; CINAHL; Web of Science; Cambridge Scientific Abstracts; ICTRP; and additional sources for published and unpublished randomized control trials. The date of the search was November 6, 2013. Outcomes were grouped using a framework suggested by the Cochrane Effective Practice and Organization of Care group.
RESULTS: Patient outcomes included adherence to hearing aid use, daily hours of aid use, hearing handicap, hearing aid benefit, quality of life, and communication and psychological outcome. Satisfaction and speech perception were frequent secondary outcomes. There was diversity in measures used to report patient outcomes. Outcome categories other than patient health status and behavior were rarely reported. The timing of outcome measurement was often short term (<12 weeks), with a relative lack of evidence on long-term outcomes (>1 year).
CONCLUSIONS: This review has highlighted considerable diversity in patient-reported outcome measurements in randomized control trials in the context of adult auditory rehabilitation. In addition, there are gaps in the literature with respect to measurement of other outcome types of potential interest to stakeholders, including policymakers and commissioners. Long-term outcome assessment is rare.
PMID: 25919402 [PubMed - indexed for MEDLINE]
Related Articles |
Outcome Measurement in Adult Auditory Rehabilitation: A Scoping Review of Measures Used in Randomized Controlled Trials.
Ear Hear. 2015 Sep-Oct;36(5):567-73
Authors: Barker F, MacKenzie E, Elliott L, de Lusignan S
Abstract
OBJECTIVES: This review documented the range and nature of reported outcome measures in the context of adult auditory rehabilitative research.
DESIGN: A scoping review conducted as a part of the development of a systematic review of the effect of interventions to improve hearing aid use. The authors searched the Cochrane Ear, Nose and Throat Disorders Group Trials Register; the Cochrane Central Register of Controlled Trials; PubMed; EMBASE; CINAHL; Web of Science; Cambridge Scientific Abstracts; ICTRP; and additional sources for published and unpublished randomized control trials. The date of the search was November 6, 2013. Outcomes were grouped using a framework suggested by the Cochrane Effective Practice and Organization of Care group.
RESULTS: Patient outcomes included adherence to hearing aid use, daily hours of aid use, hearing handicap, hearing aid benefit, quality of life, and communication and psychological outcome. Satisfaction and speech perception were frequent secondary outcomes. There was diversity in measures used to report patient outcomes. Outcome categories other than patient health status and behavior were rarely reported. The timing of outcome measurement was often short term (<12 weeks), with a relative lack of evidence on long-term outcomes (>1 year).
CONCLUSIONS: This review has highlighted considerable diversity in patient-reported outcome measurements in randomized control trials in the context of adult auditory rehabilitation. In addition, there are gaps in the literature with respect to measurement of other outcome types of potential interest to stakeholders, including policymakers and commissioners. Long-term outcome assessment is rare.
PMID: 25919402 [PubMed - indexed for MEDLINE]