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1.
J Clin Gastroenterol ; 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38227842

RESUMO

OBJECTIVE: The aims of this study are to determine the functional luminal imaging probe's (FLIP) diagnostic utility by comparing FLIP measurements with results from other esophageal evaluation standards. BACKGROUND: The FLIP is an esophageal evaluation technique performed at the time of endoscopy. Few studies have evaluated FLIP diagnostic capabilities compared with the established testing techniques, including high-resolution manometry (HRIM), time barium esophagram (TBE), and 24-hour impedance-pH monitoring. PATIENTS AND METHODS: A retrospective review was performed for 413 preintervention patients who underwent FLIP testing during endoscopy. Data from HRIM, 24-hour pH monitoring, and TBE were compared. RESULTS: Abnormal Distensibility Index (DI) was associated with abnormal integrated relaxation pressure (IRP; P = 0.003). Average DI was higher in patients with abnormal IRP (>15 mm Hg) when a hiatal hernia was present (P = 0.025). The total agreement between correlated diagnoses from FLIP and HRIM was 33.5%. DI was not associated with acid exposure time on pH monitoring. Agreement between FLIP and TBE was 49% with a sensitivity of 98.1% and a specificity of 36.5%. A 60 mL distension had a significantly lower detection rate than 40 mL and 50 mL for active peristalsis and was unaffected by pressure (P < 0.05). CONCLUSIONS: FLIP as an adjunct to HRIM is supported by strong metric correlation. FLIP was not correlated to pH monitoring findings, suggesting FLIP is not useful in reflux assessment. The agreement between FLIP and TBE was lower than in previous studies. Hiatal hernia impacted the normality between DI and IRP, not between FLIP and TBE. We suggest analyzing peristaltic patterns on panometry at all fill volumes to optimize detection.

2.
Reg Environ Change ; 22(3): 93, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36161075

RESUMO

Intensification of the hydrological cycle resulting from climate change in West Africa poses significant risks for the region's rapidly urbanising cities, but limited research on flood risk has been undertaken at the urban domain scale. Furthermore, conventional climate models are unable to realistically represent the type of intense storms which dominate the West African monsoon. This paper presents a decision-first framing of climate research in co-production of a climate-hydrology-flooding modelling chain, linking scientists working on state-of-the-art regional climate science with decision-makers involved in city planning for future urban flood management in the city of Ouagadougou, Burkina Faso. The realistic convection-permitting model over Africa (CP4A) is applied at the urban scale for the first time and data suggest significant intensification of high-impact weather events and demonstrate the importance of considering the spatio-temporal scales in CP4A. Hydrological modelling and hydraulic modelling indicate increases in peak flows and flood extents in Ouagadougou in response to climate change which will be further exacerbated by future urbanisation. Advances in decision-makers' capability for using climate information within Ouagadougou were observed, and key recommendations applicable to other regional urban areas are made. This study provides proof of concept that a decision-first modelling-chain provides a methodology for co-producing climate information that can, to some extent, bridge the usability gap between what scientists think is useful and what decision-makers need. Supplementary Information: The online version contains supplementary material available at 10.1007/s10113-022-01943-x.

3.
J Acoust Soc Am ; 147(1): 273, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32006979

RESUMO

Masked sentence perception by hearing-aid users is strongly correlated with three variables: (1) the ability to hear phonetic details as estimated by the identification of syllable constituents in quiet or in noise; (2) the ability to use situational context that is extrinsic to the speech signal; and (3) the ability to use inherent context provided by the speech signal itself. This approach is called "the syllable-constituent, contextual theory of speech perception" and is supported by the performance of 57 hearing-aid users in the identification of 109 syllable constituents presented in a background of 12-talker babble and the identification of words in naturally spoken sentences presented in the same babble. A simple mathematical model, inspired in large part by Boothroyd and Nittrouer [(1988). J. Acoust. Soc. Am. 84, 101-114] and Fletcher [Allen (1996) J. Acoust. Soc. Am. 99, 1825-1834], predicts sentence perception from listeners' abilities to recognize isolated syllable constituents and to benefit from context. When the identification accuracy of syllable constituents is greater than about 55%, individual differences in context utilization play a minor role in determining the sentence scores. As syllable-constituent scores fall below 55%, individual differences in context utilization play an increasingly greater role in determining sentence scores. Implications for hearing-aid design goals and fitting procedures are discussed.


Assuntos
Ruído , Pessoas com Deficiência Auditiva/psicologia , Fonética , Percepção da Fala , Estimulação Acústica , Idoso , Idoso de 80 Anos ou mais , Feminino , Auxiliares de Audição , Humanos , Masculino , Pessoa de Meia-Idade , Mascaramento Perceptivo , Reconhecimento Psicológico
4.
J Acoust Soc Am ; 141(4): 2933, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28464618

RESUMO

The abilities of 59 adult hearing-aid users to hear phonetic details were assessed by measuring their abilities to identify syllable constituents in quiet and in differing levels of noise (12-talker babble) while wearing their aids. The set of sounds consisted of 109 frequently occurring syllable constituents (45 onsets, 28 nuclei, and 36 codas) spoken in varied phonetic contexts by eight talkers. In nominal quiet, a speech-to-noise ratio (SNR) of 40 dB, scores of individual listeners ranged from about 23% to 85% correct. Averaged over the range of SNRs commonly encountered in noisy situations, scores of individual listeners ranged from about 10% to 71% correct. The scores in quiet and in noise were very strongly correlated, R = 0.96. This high correlation implies that common factors play primary roles in the perception of phonetic details in quiet and in noise. Otherwise said, hearing-aid users' problems perceiving phonetic details in noise appear to be tied to their problems perceiving phonetic details in quiet and vice versa.


Assuntos
Correção de Deficiência Auditiva/instrumentação , Auxiliares de Audição , Perda Auditiva Neurossensorial/reabilitação , Ruído/efeitos adversos , Mascaramento Perceptivo , Pessoas com Deficiência Auditiva/reabilitação , Acústica da Fala , Percepção da Fala , Qualidade da Voz , Estimulação Acústica , Adulto , Idoso , Idoso de 80 Anos ou mais , Audiometria de Tons Puros , Audiometria da Fala , Limiar Auditivo , Estimulação Elétrica , Feminino , Audição , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Neurossensorial/fisiopatologia , Perda Auditiva Neurossensorial/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Pessoas com Deficiência Auditiva/psicologia , Fonética , Inteligibilidade da Fala
5.
Semin Hear ; 36(4): 273-83, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27587914

RESUMO

Following an overview of theoretical issues in speech-perception training and of previous efforts to enhance hearing aid use through training, a multisite study, designed to evaluate the efficacy of two types of computerized speech-perception training for adults who use hearing aids, is described. One training method focuses on the identification of 109 syllable constituents (45 onsets, 28 nuclei, and 36 codas) in quiet and in noise, and on the perception of words in sentences presented in various levels of noise. In a second type of training, participants listen to 6- to 7-minute narratives in noise and are asked several questions about each narrative. Two groups of listeners are trained, each using one of these types of training, performed in a laboratory setting. The training for both groups is preceded and followed by a series of speech-perception tests. Subjects listen in a sound field while wearing their hearing aids at their usual settings. The training continues over 15 to 20 visits, with subjects completing at least 30 hours of focused training with one of the two methods. The two types of training are described in detail, together with a summary of other perceptual and cognitive measures obtained from all participants.

6.
J Am Acad Audiol ; 23(10): 757-67, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23169193

RESUMO

BACKGROUND: An estimated 36 million US citizens have impaired hearing, but nearly half of them have never had a hearing test. As noted by a recent National Institutes of Health/National Institute on Deafness and Other Communication Disorders (NIH/NIDCD) Working Group, "In the United States (in contrast to many other nations) there are no readily accessible low cost hearing screening programs…" (Donahue et al, 2010, p. 2). Since 2004, telephone administered screening tests utilizing three-digit sequences presented in noise have been developed, validated, and implemented in seven countries. Each of these tests has been based on a test protocol conceived by Smits and colleagues in The Netherlands. PURPOSE: Investigators from Communication Disorders Technology, Inc., Indiana University, and VU University Medical Center of Amsterdam agreed to collaborate in the development and validation of a screening test for hearing impairment suitable for delivery over the telephone, for use in the United States. This test, utilizing spoken three-digit sequences (triplets), was to be based on the design of Smits and his colleagues. RESEARCH DESIGN: A version of the digits-in-noise test was developed utilizing digit triplets spoken in Middle American dialect. The stimuli were individually adjusted to speech-to-noise ratio (SNR) values yielding 50% correct identification, on the basis of data collected from a group of 10 young adult listeners with normal hearing. A final set of 64 homogeneous stimuli were selected from an original 160 recorded triplets. Each test consisted of a series of 40 triplets drawn at random, presented in a noise background. The SNR threshold for 50% correct identification of the triplets was determined by a one-down, one-up adaptive procedure. The test was implemented by telephone, and administered to listeners with varying levels of hearing impairment. The listeners were then evaluated with pure-tone tests and other audiometric measures as clinically appropriate. STUDY SAMPLE: Ninety participants included 72 who were volunteers from the regular client population at the Indiana University Hearing Clinic, and 18 who were recruited with a newspaper ad offering a free hearing test. Of the 90 participants, 49 were later determined to have mean pure-tone thresholds greater than 20 dB hearing level (HL). DATA COLLECTION AND ANALYSIS: The primary data analyses were correlations between telephone test thresholds and other measures, including pure-tone thresholds and speech recognition tests, collected for the same participants. RESULTS: The correlation between the telephone test and pure-tone thresholds (r = 0.74) was within the range of correlations observed with successful telephone screening tests in use in other countries. Thresholds based on the average of only 21 trials (trials five through 25 of the 40-trial tracking history) yielded sensitivity and specificity values of 0.80 and 0.83, respectively, using pure-tone average((0.5, 1.0, 2.0 kHz)) >20 dB HL as the criterion measure. CONCLUSIONS: This US version of the digits-in-noise telephone screening test is sufficiently valid to be implemented for use by the general public. Its properties are quite similar to those telephone screening tests currently in use in most European countries. Telephone tests provide efficient, easy to use, and valid screening for functional hearing impairment. The results of this test are a reasonable basis for advising those who fail to seek a comprehensive hearing evaluation by an audiologist.


Assuntos
Audiometria de Tons Puros/métodos , Audiometria de Tons Puros/normas , Transtornos da Audição/diagnóstico , Programas de Rastreamento/métodos , Programas de Rastreamento/normas , Telefone , Estimulação Acústica/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Limiar Auditivo , Feminino , Transtornos da Audição/fisiopatologia , Humanos , Internacionalidade , Masculino , Pessoa de Meia-Idade , Percepção da Fala , Estados Unidos , Adulto Jovem
7.
Trials ; 11: 112, 2010 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-21092099

RESUMO

Sharing of final research data from clinical research is an essential part of the scientific method. The U.S. National Institutes of Health require some grant applications to include plans for sharing final research data, which it defines as the factual materials necessary to document, support, and validate research findings. In the U.S., however, the Privacy Rule adopted under the Health Insurance Portability and Accountability Act impedes the sharing of final research data. In most situations, final research data may be shared only where all information that could possibly be used to identify the subject has been deleted, or where the subject has given authorization for specific research, or an Institutional Review Board has granted a waiver.


Assuntos
Pesquisa Biomédica , Health Insurance Portability and Accountability Act , Disseminação de Informação , Privacidade , Humanos , Estados Unidos
11.
Regul Toxicol Pharmacol ; 52(1 Suppl): S5-S10, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17997209

RESUMO

The Biwabik Iron Formation is a approximately 1.9 billion year-old sequence of iron-rich sedimentary rocks that was metamorphosed at its eastern-most extent by approximately 1.1 billion year-old intrusions of the Duluth Complex. The metamorphic recrystallization of iron-formation locally produced iron-rich amphiboles and other fibrous iron-silicate minerals. The presence of these minerals in iron-formation along the eastern part of what is known as the Mesabi Iron Range, and their potential liberation by iron mining has raised environmental health concerns. We describe here the geologic setting and mineralogic composition of the Biwabik Iron Formation in and adjacent to the contact metamorphic aureole of the Duluth Complex. The effects of metamorphism are most pronounced within a few kilometers of the contact, and decrease progressively away from it. The contact aureole has been divided into four metamorphic zones-each characterized by the composition and crystal structure of the metamorphic minerals it contains. The recrystallization of iron-formation to iron-rich amphibole minerals (grunerite and cummingtonite) and iron-pyroxene minerals (hedenbergite and ferrohypersthene) is best developed in zones that are most proximal to the Duluth Complex contact.


Assuntos
Sedimentos Geológicos/química , Geologia , Ferro/química , Minerais/química , Mineração , Planeta Terra , Evolução Planetária , Ferro/análise , Minerais/análise , Minnesota
12.
J Acoust Soc Am ; 121(4): EL151-5, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17471760

RESUMO

Sato et al. [Acta. Otolaryngol. 111 (6), 1037-1040 (1991)] reported that the human cochlea is, on average, 15% longer for males than females. This corresponds to 4.7 mm in length and to 2.78 standard deviations (SD). Anatomical measurements of the lengths of cochleas from 148 heads (194 cochleas) from eleven sources are reviewed and summarized. A sex difference of 3.36% is observed. This corresponds to 1.11 mm in length and to 0.49 SD. The mean lengths of the male and female cochleas are approximately 34 and 33 mm, respectively, and the population SD is 2.28 mm. The statistical significance of the observed difference is questionable.


Assuntos
Órgão Espiral/anatomia & histologia , Antropometria , Cóclea/anatomia & histologia , Cóclea/fisiologia , Feminino , Humanos , Masculino , Órgão Espiral/fisiologia , Fatores Sexuais
13.
J Acoust Soc Am ; 122(5): 3063, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20228894

RESUMO

A software system, SPATS (patent pending), that tests and trains important bottom-up and combined bottom-up/top-down speech-perception skills is described. Bottom-up skills are the abilities to identify the constituents of syllables: onsets, nuclei, and codas in quiet and noise as produced by eight talkers. Top-down skills are the abilities to use knowledge of linguistic context to identify words in spoken sentences. The sentence module in SPATS emphasizes combined bottom-up/top-down abilities in perceiving sentences in noise. The word-initial onsets, stressed nuclei, and word-final codas are ranked in importance and grouped into subsets based on their importance. Testing utilizes random presentation of all the items included in a subset. Training in Quiet (SNR = 40 dB) or in Noise (SNR = 5 dB), is adaptively focused on individual listener's learnable items of intermediate difficulty. Alternatively, SNR-adaption training uses Kaernbach's algorithm to find the SNR required for a target percent correct. The unique sentence module trains the combination of bottom-up (hearing) with top-down (use of linguistic context) abilities to identify words in meaningful sentences in noise. Scoring in the sentence module is objective and automatic.

14.
J Acoust Soc Am ; 114(6 Pt 1): 3363-7, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14714816

RESUMO

A sensitive, large-aperture schlieren optical instrument is applied to observe gas-dynamic phenomena at the exit of a trumpet. Shock waves are seen, especially for loud, high-pitched trumpet notes, and several illustrations are given. Microphone waveforms are given for representative examples. These shock waves arise from the shock-tube-like effect of the performer's intermittent breath pressure driving the cylindrical duct of the trumpet, and are the result of cumulative nonlinear acoustic propagation inside the trumpet bore. They are, however, very weak, traveling only marginally above the acoustic speed. In the 118-124 peak dB(A) range, they are near the weak limit of shock wave visibility by schlieren optics. The schlieren evidence confirms that the frequency of the emitted shock waves corresponds to the frequency of the note being played. Ancillary laminar and turbulent jet phenomena associated with the performer's breath are also visible in the images.


Assuntos
Acústica , Pressão do Ar , Ondas de Choque de Alta Energia , Música , Refratometria , Espectrografia do Som , Humanos , Processamento de Imagem Assistida por Computador , Dinâmica não Linear , Gravação de Videoteipe
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