36 resultados para Hearing (Physiology)

em Repositório Institucional UNESP - Universidade Estadual Paulista "Julio de Mesquita Filho"


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The teaching of hearing physiology requires an knowledge integration of Human Anatomy, Biophysics, more precisely Bioacoustics and Bioelectrogenesis, as well as Neurophysiology. Students present difficulty to build knowledge about functional mechanisms of sound conduction and sensory transduction, especially if the elements are not visible forms, as the middle and inner ear structures. To make the teaching about hearing physiology and sensory perception easier, was produced a set of didactical materials about the subject. At first, a resin model that faithfully describes the anatomical relationship of the ossicles with the tympanic membrane was developed. Subsequently, a second model that, besides illustrates the mechanism of acoustic impedance overcoming, also reveals how acoustic sensorial transduction occurs in inner ear, was designed and produced. In the third didactical model, are visualized, through students interaction, areas of the cerebral cortex that interpret the different sensory modalities. In addition, were created three educational videos about hearing problems and a site on Human Hearing Physiology, available on Institute of Biosciences website. The results of this course conclusion monograph are presented in the form of articles that were submitted to Journal Physics in the School and the Journal of the Nucleus of Teaching

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The objective of this work was to evaluate the effect of environmental variables on dairy buffaloes physiology in two different places after milking, shaded plus artificial ventilation and another one non-shaded, in Ribeira Valley, São Paulo State, Brazil. Data on the respiratory rate (RR) and the surface temperature (ST) at udder, neckmiddle, forehead, back middle and rump were collected in 12 dairy buffaloes at autumn. In the same way, it were recorded the black globe temperature in the sun (GTS) and in the shade (GTNS), air temperature and wind speed at padronized height of 1.60 meters. All data were collected at 10:30am and 1:30pm. The results showed statistical difference among black globe temperature, wind speed, RR and ST (P<0.01) in two treatments.The results showed the necessity of protection against the solar radiation in the buffaloes, even in periods of warm climates.

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European corn borer (ECB) [Ostrinia nubilalis (Hubner)] (Lepidoptera: Crambidae) is known to infest Irish potato (Solanum tuberosum L.) but only causes economic damage during the first generation in East Coast potato producing areas. However, in Nebraska, second generation ECB infest potato plants during the bulking period and may reduce yield and/or potato quality. Experiments were conducted in 2001, 2002, and 2003 to examine physiological and yield effects of second generation ECB injury to potato in Nebraska. Pike, Atlantic, and three Frito Lay proprietary varieties (FL1867, FL1879, and FL1833) were used. Experimental plots were infested with four ECB egg masses per plant to simulate ECB infestation by second-generation larvae; controls received no egg masses. Photosynthetic rates, tuber weights, tuber size grades, solids, and fry quality were measured. Potato plants with ECB infestation had significantly reduced photosynthetic rates on ECB-infested stems and on uninfested stems on the same plant when larvae were in the fifth instar. When insects were in the fourth instar, photosynthetic rates were reduced only on ECB-infested stems. In 2001, ECB infestation reduced the average mass of large tubers and increased the amount of small tubers in FL1867 and FL1879. In 2002, significant yield reductions were not observed. Across both years, ECB-infested plots produced fewer large (65- to 100-mm diam.) tubers than control plots. Other tuber properties and chip qualities were unaffected. This study indicates that second generation ECB infestation of approximately 30% infested plants results in economic loss for some chipping varieties and affects tuber bulking. In contrast to east coast growers, Midwest potato farmers must be concerned with second generation ECB.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The purpose of this study was to determine the influence of hearing protection devices (HPDs) on the understanding of speech in young adults with normal hearing, both in a silent situation and in the presence of ambient noise. The experimental research was carried out with the following variables: five different conditions of HPD use (without protectors, with two earplugs and with two earmuffs); a type of noise (pink noise); 4 test levels (60, 70, 80 and 90 dB[A]); 6 signal/noise ratios (without noise, + 5, + 10, zero, - 5 and - 10 dB); 5 repetitions for each case, totalling 600 tests with 10 monosyllables in each one. The variable measure was the percentage of correctly heard words (monosyllabic) in the test. The results revealed that, at the lowest levels (60 and 70 dB), the protectors reduced the intelligibility of speech (compared to the tests without protectors) while, in the presence of ambient noise levels of 80 and 90 dB and unfavourable signal/noise ratios (0, -5 and -10 dB), the HPDs improved the intelligibility. A comparison of the effectiveness of earplugs versus earmuffs showed that the former offer greater efficiency in respect to the recognition of speech, providing a 30% improvement over situations in which no protection is used. As might be expected, this study confirmed that the protectors' influence on speech intelligibility is related directly to the spectral curve of the protector's attenuation. (C) 2003 Elsevier B.V. Ltd. All rights reserved.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Aims: To determine the occurrence of isolated and recurrent episodes of conductive hearing loss (CHL) during the first two years of life in very low birth weight (VLBW) infants with and without bronchopulmonary dysplasia (BPD).Study design, subjects and outcome measures: In a longitudinal clinical study. 187 children were evaluated at 6, 9, 12,15 18 and 24 months of age by visual reinforcement audiometry, tympanometry and auditory brain response system.Results: of the children with BPD, 54.5% presented with episodes of CHL, as opposed to 34.7% of the children without BPD. This difference was found to be statistically significant. The recurrent or persistent episodes were more frequent among children with BPD (25.7%) than among those without BPD (8.3%). The independent variables that contributed to this finding were small for gestational age and a 5 min Apgar score.Conclusions: Recurrent CHL episodes are more frequent among VLBW infants with BPD than among VLBW infants without BPD. (C) 2010 Elsevier B.V. All rights reserved.

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Os sistemas de telecomunicações emitem radiofreqüência, uma radiação eletromagnética invisível. Telefones celulares transmitem microondas (450900 MHz no sistema analógico e 1,82,2 GHz no sistema digital), muito próximo à orelha do usuário. Esta energia é absorvida pela pele, orelha interna, nervo vestibulococlear e superfície do lobo temporal. OBJETIVO: Revisar a literatura sobre influência dos telefones celulares na audição e equilíbrio. FORMA DE ESTUDO: Revisão sistemática. METODOLOGIA: Foram pesquisados artigos nas bases Lilacs e Medline sobre a influência dos telefones celulares nos sistemas auditivo e vestibular, publicados de 2000 a 2005, e também materiais veiculados na Internet. RESULTADOS: Os estudos sobre radiação do telefone celular e risco de neurinoma do acústico apresentam resultados contraditórios. Alguns autores não encontram maior probabilidade de aparecimento do tumor nos usuários de celulares, enquanto outros relatam que a utilização de telefones analógicos por 10 anos ou mais aumenta o risco para o tumor. A exposição aguda às microondas emitidas pelo celular não influencia a atividade das células ciliadas externas da cóclea, in vivo e in vitro, a condução elétrica no nervo coclear, nem a fisiologia do sistema vestibular em humanos. As próteses auditivas analógicas são mais suscetíveis à interferência eletromagnética dos telefones celulares digitais. CONCLUSÃO: Não há comprovação de lesão cocleovestibular pelos telefones celulares.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Thermal and water balance are coupled in anurans, and species with particularly permeable skin avoid overheating more effectively than minimizing variance of body temperature. In turn, temperature affects muscle performance in several ways, so documenting the mean and variance of body temperature of active frogs can help explain variation in behavioral performance. The two types of activities studied in most detail, jumping and calling, differ markedly in duration and intensity, and there are distinct differences in the metabolic profile and fiber type of the supporting muscles. Characteristics of jumping and calling also vary significantly among species, and these differences have a number of implications that we discuss in some detail throughout this paper. One question that emerges from this topic is whether anuran species exhibit activity temperatures that match the temperature range over which they perform best. Although this seems the case, thermal preferences are variable and may not necessarily reflect typical activity temperatures. The performance versus temperature curves and the thermal limits for anuran activity reflect the thermal ecology of species more than their systematic position. Anuran thermal physiology, therefore, seems to be phenotypically plastic and susceptible to adaptive evolution. Although generalizations regarding the mechanistic basis of such adjustments are not yet possible, recent attempts have been made to reveal the mechanistic basis of acclimation and acclimatization. (C) 2007 Elsevier B.V. All rights reserved.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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O trato olivococlear medial realiza o controle eferente das células ciliadas externas, regulando as contrações lentas e atenuando as rápidas. Com a pesquisa da amplitude das emissões otoacústicas sem e com estimulação acústica contra, ipsi ou bilateralmente, é possível estimar as condições desse trato, uma vez que o efeito resultante de redução/supressão das emissões indica seu funcionamento. O envelhecimento implica em diminuição da atividade do sistema auditivo central, em função da degeneração das estruturas envolvidas nas habilidades auditivas. OBJETIVO: O objetivo foi investigar o efeito da idade na atividade do trato sobre a cóclea, com a análise da amplitude das emissões com estimulação acústica contralateral. MATERIAL E MÉTODO: A casuística foi composta por 75 indivíduos agrupados conforme a idade. A metodologia foi o modo convencional, com clique linear e o ruído branco. ESTUDO DE CASO: A análise considerou a resposta das orelhas e a comparação entre os grupos. RESULTADOS: Os resultados revelam diferenças estatisticamente significantes entre o response das emissões sem e com estimulação acústica contralateral, nos indivíduos (20 a 39 anos). O efeito redução/supressão das emissões diminui com a idade (quarta década). CONCLUSÃO: O envelhecimento prejudica a efetividade da atividade do trato.