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1.
Eur Ann Otorhinolaryngol Head Neck Dis ; 139(1): 21-27, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34140263

RESUMO

OBJECTIVES: This document presents the fundamentals of speech audiometry in noise, general requirements for implementation and criteria for choice among the tests available in French according to the health-professional's needs. MATERIAL AND METHODS: The recommendations are based on a systematic analysis of the literature carried out by a multidisciplinary group of doctors, audiologists and audioprosthetists from all over France. They are graded A, B, C or expert opinion according to decreasing level of scientific evidence. RESULTS: Eight tests of speech audiometry in noise can be used in France. CONCLUSION: To be complete, evaluation of hearing status requires testing understanding of speech in noise. The examination must begin with a minimum of two measurements familiarizing the subject with the test procedure. For initial diagnosis, adaptive procedures establishing the 50% speech reception threshold (SRT50) in noise are to be preferred in order to obtain a rapid and standardized measurement of perception of speech in noise. When the aim is to measure real-life speech comprehension, tests based on sentences, cocktail-party noise and free-field stimulation are to be preferred. Prosthetic gain is evaluated exclusively in free field. This is the only way to evaluate the contribution of binaurality and to measure perception in noise in an environment as close as possible to real life. In order to avoid acoustic interference in free field, at least five loudspeakers should be used, in particular for evaluating the effectiveness of directional microphones, CROS devices enabling sounds picked up in the damaged ear to be rerouted to the functional ear, or bimodal fitting (i.e., when hearing is enabled by two modalities: for example, hearing aid for one ear, cochlear implant for the other).


Assuntos
Audiologia , Implantes Cocleares , Auxiliares de Audição , Otolaringologia , Percepção da Fala , Adulto , Humanos , Fala
2.
Moulineaux; European Annals of Otorhinolaryngology, Head and Neck Diseases; Jun. 14, 2021.
Não convencional em Inglês | BIGG - guias GRADE | ID: biblio-1291637

RESUMO

This document presents the fundamentals of speech audiometry in noise, general requirements for implementation and criteria for choice among the tests available in French according to the health-professional's needs. The recommendations are based on a systematic analysis of the literature carried out by a multidisciplinary group of doctors, audiologists and audioprosthetists from all over France. They are graded A, B, C or expert opinion according to decreasing level of scientific evidence. Eight tests of speech audiometry in noise can be used in France. To be complete, evaluation of hearing status requires testing understanding of speech in noise. The examination must begin with a minimum of two measurements familiarizing the subject with the test procedure. For initial diagnosis, adaptive procedures establishing the 50% speech reception threshold (SRT50) in noise are to be preferred in order to obtain a rapid and standardized measurement of perception of speech in noise. When the aim is to measure real-life speech comprehension, tests based on sentences, cocktail-party noise and free-field stimulation are to be preferred. Prosthetic gain is evaluated exclusively in free field. This is the only way to evaluate the contribution of binaurality and to measure perception in noise in an environment as close as possible to real life. In order to avoid acoustic interference in free field, at least five loudspeakers should be used, in particular for evaluating the effectiveness of directional microphones, CROS devices enabling sounds picked up in the damaged ear to be rerouted to the functional ear, or bimodal fitting (i.e., when hearing is enabled by two modalities: for example, hearing aid for one ear, cochlear implant for the other).


Assuntos
Humanos , Audiometria da Fala/métodos , Perda Auditiva/diagnóstico , França
3.
Int J Pediatr Otorhinolaryngol ; 141: 110557, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33341717

RESUMO

Enlarged vestibular aqueduct (EVA) is a common finding in tomodensitometry. When cranial MRI is performed, enlarged endolymphatic sac (EES) can also be found. Profound hearing loss is a common finding in these patients but a few studies have investigated vestibular function after cochlear implantation (CI) in EVA and EES patients. Our main objective was to find out whether in EVA children candidates to CI, a higher endolymphatic sac (ES) volume was predictive for higher rates of postsurgical vestibular complications. METHODS: We retrospectively included EVA children who benefited from CI, during the last 2 years. Two groups were constituted according to the presence or not of a vestibular impairment (decrease in the VOR gain on the VHIT test on one of the semicircular canals and/or a loss of cVEMPs) 6 months after CI. Endolymphatic volume of both VA and ES was measured for each patient. RESULTS: Fifteen patients were included. The mean endolymph volume was significantly higher in the impaired group (0.40 cm3 ± 0.23, range 0.08-0.70) than in the non-impaired group (0.11 cm3 ± 0.07, range 0.04-0.29; p = 0.029). Four children of the impaired group were followed during one year. At the end of vestibular rehabilitation, all children recovered a lateral canal function and a saccular function. CONCLUSION: In EVA children, a combined EES appears to increase the risk of severe post CI vestibular impairment. To minimize this risk prior CI surgery, besides tomodensitometry, MRI measurement of the ES volume should be systematically performed.


Assuntos
Implante Coclear , Saco Endolinfático , Perda Auditiva Neurossensorial , Aqueduto Vestibular , Criança , Saco Endolinfático/diagnóstico por imagem , Saco Endolinfático/cirurgia , Humanos , Estudos Retrospectivos , Aqueduto Vestibular/anormalidades , Aqueduto Vestibular/diagnóstico por imagem , Aqueduto Vestibular/cirurgia
4.
Braz J Biol ; 70(3 Suppl): 697-708, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21085776

RESUMO

After 500 years of exploitation and destruction, the Brazilian Atlantic Forest has been reduced to less the 8% of its original cover, and climate change may pose a new threat to the remnants of this biodiversity hotspot. In this study we used modelling techniques to determine present and future geographical distribution of 38 species of trees that are typical of the Brazilian Atlantic Forest (Mata Atlântica), considering two global warming scenarios. The optimistic scenario, based in a 0.5% increase in the concentration of CO2 in the atmosphere, predicts an increase of up to 2 °C in the Earth's average temperature; in the pessimistic scenario, based on a 1% increase in the concentration of CO2 in the atmosphere, temperature increase may reach 4 °C. Using these parameters, the occurrence points of the studied species registered in literature, the Genetic Algorithm for Rule-set Predictions/GARP and Maximum entropy modeling of species geographic distributions/MaxEnt we developed models of present and future possible occurrence of each species, considering Earth's mean temperature by 2050 with the optimistic and the pessimistic scenarios of CO2 emission. The results obtained show an alarming reduction in the area of possible occurrence of the species studied, as well as a shift towards southern areas of Brazil. Using GARP, on average, in the optimistic scenario this reduction is of 25% while in the pessimistic scenario it reaches 50%, and the species that will suffer the worst reduction in their possible area of occurrence are: Euterpe edulis, Mollinedia schottiana, Virola bicuhyba, Inga sessilis and Vochysia magnifica. Using MaxEnt, on average, in the optimistic scenario the reduction will be of 20% while in the pessimistic scenario it reaches 30%, and the species that will suffer the worst reduction are: Hyeronima alchorneoides, Schefflera angustissima, Andira fraxinifolia and the species of Myrtaceae studied.


Assuntos
Biodiversidade , Previsões , Aquecimento Global , Modelos Biológicos , Árvores , Brasil , Ecossistema , Árvores/classificação
5.
Braz J Biol ; 69(3): 935-42, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19802455

RESUMO

The germination response of Ocotea pulchella (Nees) Mez seeds to light, temperature, water level and pulp presence is introduced. The laboratory assays were carried out in germination chambers and thermal-gradient apparatus, whereas the field assays were performed in environments with distinct light, temperature and soil moisture conditions within a permanent parcel of Restinga forest of the Parque Estadual da Ilha do Cardoso, Cananéia, São Paulo. The seeds do not exhibit dormancy, they are non photoblastic, and a loss of viability in dry stored seeds can be related to a decrease in water content of the seed. The presence of the pulp and the flooded substratum influenced negatively the germination of O. pulchella seeds tested in the laboratory. Otherwise, light and temperature probably are not limiting factors of the germination of O. pulchella seeds in the natural environment of Restinga. The optimum temperature range for germination of Ocotea pulchella seeds was 20 to 32 degrees C, the minimum or base temperature estimated was 11 degrees C and the maximum ranged between 33 and 42 degrees C. The isotherms exhibited a sigmoidal pattern well described by the Weibull model in the sub-optimal temperature range. The germinability of O. pulchella seeds in the understorey, both in wet and dry soil, was higher than in gaps. Germination was not affected by fluctuations in soil moisture content in the understorey environment, whereas in gaps, germination was higher in wet soils. Thus, the germination of this species involves the interaction of two or more factors and it cannot be explained by a single factor.


Assuntos
Germinação/fisiologia , Ocotea/crescimento & desenvolvimento , Brasil , Clima Desértico , Umidade , Laboratórios , Luz , Ocotea/fisiologia , Estações do Ano , Temperatura , Água
6.
Braz. j. biol ; 69(3): 935-942, Aug. 2009. graf
Artigo em Inglês | LILACS | ID: lil-527164

RESUMO

The germination response of Ocotea pulchella (Nees) Mez seeds to light, temperature, water level and pulp presence is introduced. The laboratory assays were carried out in germination chambers and thermal-gradient apparatus, whereas the field assays were performed in environments with distinct light, temperature and soil moisture conditions within a permanent parcel of Restinga forest of the Parque Estadual da Ilha do Cardoso, Cananéia, São Paulo. The seeds do not exhibit dormancy, they are non photoblastic, and a loss of viability in dry stored seeds can be related to a decrease in water content of the seed. The presence of the pulp and the flooded substratum influenced negatively the germination of O. pulchella seeds tested in the laboratory. Otherwise, light and temperature probably are not limiting factors of the germination of O. pulchella seeds in the natural environment of Restinga. The optimum temperature range for germination of Ocotea pulchella seeds was 20 to 32 ºC, the minimum or base temperature estimated was 11 ºC and the maximum ranged between 33 and 42 ºC. The isotherms exhibited a sigmoidal pattern well described by the Weibull model in the sub-optimal temperature range. The germinability of O. pulchella seeds in the understorey, both in wet and dry soil, was higher than in gaps. Germination was not affected by fluctuations in soil moisture content in the understorey environment, whereas in gaps, germination was higher in wet soils. Thus, the germination of this species involves the interaction of two or more factors and it cannot be explained by a single factor.


É apresentada a germinação de sementes de Ocotea pulchella (Nees) Mez em resposta a: luz, temperatura, nível de água e presença de polpa. Os ensaios de laboratório foram realizados em câmaras de germinação e em equipamento de gradiente térmico, e os de campo, em ambientes com diferentes condições de luz, temperatura e umidade no solo, em uma parcela permanente em floresta de Restinga no Parque Estadual da Ilha do Cardoso, Cananéia, São Paulo. As sementes de Ocotea pulchella não possuem dormência, são afotoblásticas, e a perda de viabilidade de sementes armazenadas a seco pode estar relacionada a um decréscimo no seu conteúdo de água. A presença da polpa e o substrato alagado afetaram negativamente a germinação de O. pulchella em laboratório. Luz e temperatura não são provavelmente fatores limitantes da germinação de sementes de O. pulchella no ambiente natural da Restinga. A faixa térmica ótima de germinação foi de 20 a 32 ºC; a temperatura mínima ou base foi estimada em 11 ºC; e a temperatura máxima variou de 33 a 42 ºC. As isotermas na faixa térmica infraótima exibem padrão sigmoidal e foram bem descritas pelo modelo de Weibull. A germinabilidade no sub-bosque, tanto em solo com maior umidade como em solo mais seco, foi maior do que em clareira. No sub-bosque não houve diferença na germinação em relação a variações na umidade do solo, ao passo que em clareiras a germinabilidade foi maior em solo mais úmido. Assim, a germinação dessa espécie deve ser função da interação de fatores, não podendo ser explicada apenas por um único fator.


Assuntos
Germinação/fisiologia , Ocotea/crescimento & desenvolvimento , Brasil , Clima Desértico , Umidade , Laboratórios , Luz , Ocotea/fisiologia , Estações do Ano , Temperatura , Água
7.
Oecologia ; 91(4): 511-517, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28313503

RESUMO

Woody plants growing in cerrado and forest communities of south-east Brasil were found to have low levels of nitrate reductase activity in their leaves suggesting that nitrate ions are not an important nitrogen source in these communities. Only in the leaves of species growing in areas of disturbance, such as gaps and forest margins, were high levels of nitrate reductase present. When pot-grown plants were supplied with nitrate, leaves and roots of almost all species responded by inducing increased levels of nitrate reductase. Pioneer or colonizing species exhibited highest levels of nitrate reductase and high shoot: root nitrate reductase activities. Glutamine synthetase, glutamate synthase and glutamate dehydrogenase were present in leaves and roots of the species examined.15N-labelled nitrate and ammonium were used to compare the assimilatory characteristics of two species:Enterolobium contortisiliquum, with a high capacity to reduce nitrate, andCalophyllum brasiliense, of low capacity. The rate of nitrate assimilation in the former was five times that of the latter. Both species had similar rates of ammonium assimilation. Results for eight species of contrasting habitats showed that leaf nitrogen content increased in parallel with xylem sap nitrogen concentrations, suggesting that the ability of the root system to acquire, assimilate or export nitrate determines shoot nitrogen status. These results emphasise the importance of nitrogen transport and metabolism in roots as determinants of whole plant nitrogen status.

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