909 resultados para Variação vocal


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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Os limites interespecíficos da espécie politípica Deconychura longicauda (Dendrocolaptidae) foram investigados por uma análise conjunta, incluindo caracteres moleculares, morfológicos e vocais. Um total de 1.108 pares de bases de genes mitocondriais Cit b e ND2 foram usados para construir hipóteses filogenéticas, ao passo que os caracteres morfológicos e vocais foram analisados com métodos estatísticos univariado e multivariado. Todas as árvores filogenéticas recuperadas indicam altos níveis de diferenciação genética e estrutura filogeográfica em Deconychura longicauda, com o reconhecimento de quatro grupos principais bem apoiados, geograficamente constituídos por aves (1) do centro de endemismo Guiana no nordeste da América do Sul (2), da bacia amazônica excluindo o escudo das Guianas (3), do sopé oriental dos Andes, e (4), trans-Andinas da América do Sul e América Central. O nível de divergência genética entre estes clados varia de 6-8% (entre as aves Guianenses, não-Guianenses, do sopé dos Andes e trans-Andinas). Embora os caracteres morfológicos contribuam pouco para a diagnose em Deconychura, o canto, por outro lado, consistetemente os distinguem. Nós recomendamos com base, principalmente, em sua diagnose molecular e vocal o desdobramento de D. longicauda nas seguintes espécies filogenéticas e biológicas: Deconychura longicauda, D. pallida, D. zimmeri, D. connectens, D. typica e um táxon ainda não nomeado, endêmico do sopé oriental dos Andes.

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A dissertação foi elaborada no formato de artigo, intitulado de “Systematic revision of the spotted antpitta Hylopezus macularius, (Grallariidae), with description of a cryptic new species from brazilian Amazonia”, a ser submetido para a revista The AUK, formatado segundo os padrões da revista. Uma revisão sistemática da espécie politípica Hylopezus macularius (Grallariidae), baseada em caracteres morfométricos, de plumagem, vocais e moleculares, é apresentada. As análises morfológicas e vocais foram baseadas, respectivamente, em 45 espécimes e em 104 gravações. As filogenias moleculares basearam-se em 1.371 pares de bases de ADN dos genes mitocondriais 16S, ND2, e cyt b de 26 espécimes, incluindo diversos táxons como grupos externos. Nossos resultados revelaram a existência de um táxon não descrito, endêmico do interflúvio Xingu - Madeira, cripticamente similar morfologicamente ao paraensis, mas distinguível vocal e geneticamente do último e de todos os outros táxons agrupados sob H. macularius. As árvores moleculares obtiveram forte apoio e monofiletismo recíproco entre as quatro linhagens principais de H. macularius, três das quais correspondem aos táxons já nomeados (dilutus, macularius, e paraensis), e um ao táxon anônimo, que é descrito neste trabalho. Nós mostramos que aqueles quatro táxons são mutuamente diagnosticáveis através de uma combinação de características vocais e morfológicas, portanto recomendamos tratá-los como espécies separadas. Datas das árvores moleculares indicaram que as separações entre espécies do complexo ocorreram entre 2.92 e 0.78 milhões de anos, com as separações mais antigas concentradas no noroeste da Amazônia (através do rio Negro) e as mais recentes na parte sudeste da bacia (através do rio Xingu).

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Lepidocolaptes albolineatus (Aves: Dendrocolaptidae) é uma espécie biológica politípica, constituída pelos seguintes táxons: L. a. albolineatus, que ocorre na Área de Endemismo (AE) Guiana, L. a. duidae (AE Imeri), L .a. fuscicapillus (AE Rondônia), L. a. madeirae (AE Rondônia) e L. a .layardi (AEs Tapajós, Xingu e Belém). Os objetivos deste trabalho foram: (1) revisar a validade e a diagnosabilidade dos táxons atualmente agrupados em L. albolineatus com base em caracteres morfológicos, vocais e moleculares e (2) reavaliar os limites interespecíficos entre estes táxons. Foram mensurados 150 espécimes depositados em 8 museus do Brasil e EUA. Para a análise molecular, foram seqüenciados um total de 940 pb do gene mitocondrial ND2 para 35 indivíduos de todos os táxons de L. albolineatus. As análises filogenéticas foram realizadas nos programa PAUP 4.0 b 10 e MrBayes 3.1 utilizando-se os métodos de parcimônia (MP), máxima verossimilhança (MV) e inferência Bayesiana. A combinação de dados morfológicos e moleculares revelou a existência de 5 clados fortemente apoiados estatisticamente: clado 1 (agrupando indivíduos da AE Rondônia), clado 2 (agrupando espécimes das AE Belém, Xingu e Tapajós), clado 3 (incluindo espécimes da AE Inambari), clado 4 (incluindo indivíduos da AE Imeri) e clado 5 (agrupando indivíduos da AE Guiana). Todos os clados corresponderam a táxons já nomeados, exceto o clado 3 para o qual nenhum nome válido se encontra disponível, já que o nome fuscicapillus na verdade se aplica ao clado 1 e, portanto, deve ser considerado sinônimo sênior de madeirae. A principal separação genética e morfológica em L. albolineatus acontece entre o táxon nominal e os demais, embora cada um dos 5 clados possa ser considerado uma espécie distinta (com base no Conceito Filético Geral de Espécie) através de uma combinação única de caracteres morfológicos, vocais e moleculares diagnósticos.

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A voz e a habilidade vocal são diferentes em cada indivíduo e em cada fase da vida. Devido aos escassos estudos sobre a qualidade vocal de meninos e adolescentes durante a puberdade, o presente estudo teve como objetivo quantificar os seguintes parâmetros da análise acústica da voz: frequência fundamental, jitter, shimmer, relação harmônico-ruído e intensidade. Para entender como se dá a variação da voz com o desenvolvimento de meninos e adolescentes, esses parâmetros foram correlacionados entre si e também com o grau do desenvolvimento puberal de sujeitos do sexo masculino. Métodos: Foram sujeitos desse estudo 110 indivíduos do sexo masculino, com idade entre 11 e 20 anos, estudantes de três escolas estaduais de Macapá, onde foi feita a coleta dos dados. Os sujeitos foram divididos em 4 grupos, 32 sujeitos com idade entre 11 e 12 anos compuseram o Grupo I, 29 sujeitos com idade entre 13 e 15 anos o Grupo II, o Grupo III foi composto por 30 sujeitos com idade entre 16 e 18 anos, e o Grupo IV por sujeitos com idade entre 19 e 20 anos. Todos os sujeitos foram submetidos à gravação da voz diretamente no computador com auxilio de microfone unidirecional. Solicitou-se emissão sustentada da vogal /é/ e fala encadeada: contagem de 1 a 10 e leitura de um parágrafo pré-estabelecido. Em seguida os sujeitos foram avaliados por um médico clínico geral para caracterização do desenvolvimento puberal de acordo com os estágios descritos por Tanner. A análise vocal foi realizada com o programa acústico Voz Metria®. Resultados: Os sujeitos apresentaram F0 média durante a vogal sustentada de 223,28 Hz, 249,86 Hz, 122,63 Hz e 127,61 Hz para os Grupos I, II, III e IV respectivamente. A F0 durante a fala encadeada foi de 217,09 Hz, 246,18 Hz, 117,27 Hz e 123,42 para os Grupos I, II, III e IV respectivamente. Shimmer apresentou valores aumentados nos quatro grupos. Jitter, intensidade e a relação harmônico-ruído mantiveram-se dentro dos padrões de normalidade estabelecidos pelo programa acústico utilizado. Quanto ao desenvolvimento puberal, a maioria dos sujeitos está em G3 (n=38; 34,5%) e G4 (n=42; 38,2%) e P3 (n=34; 31%) e P4 (n=36; 32,7%). O grau de desenvolvimento puberal está correlacionado com aF0 durante a fala encadeada (p<0,001) e com a F0 durante a emissão da vogal sustentada (p<0,001) e essa correlação foi estatisticamente significante entre G2 e G5, e G3 e G5. Conclusão: Até os 15 anos os parâmetros vocais acústicos são típicos da voz infantil. Dos 16 aos 20 anos há decréscimo significativo da F0, porém a voz ainda está em processo de estabilização, com valores aumentados de shimmer. F0 é o único parâmetro correlacionado com o grau de desenvolvimento puberal. A finalização do processo de muda vocal se apresentou, na população estudada, como um evento tardio em relação ao desenvolvimento puberal.

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The process of compiling a studio vocal performance from many takes can often result in the performer producing a new complete performance once this new "best of" assemblage is heard back. This paper investigates the ways that the physical process of recording can alter vocal performance techniques, and in particular, the establishing of a definitive melodic and rhythmic structure. Drawing on his many years of experience as a commercially successful producer, including the attainment of a Grammy award, the author will analyse the process of producing a “credible” vocal performance in depth, with specific case studies and examples. The question of authenticity in rock and pop will also be discussed and, in this context, the uniqueness of the producer’s role as critical arbiter – what gives the producer the authority to make such performance evaluations? Techniques for creating conditions in the studio that are conducive to vocal performances, in many ways a very unnatural performance environment, will be discussed, touching on areas such as the psycho-acoustic properties of headphone mixes, the avoidance of intimidatory practices, and a methodology for inducing the perception of a “familiar” acoustic environment.

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This contribution proposes the effect of the studio practice compiling vocals from many takes on the performance of vocalists.

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The unique alpine-living kea parrot Nestor notabilis has been the focus of numerous cognitive studies, but its communication system has so far been largely neglected. We examined 2,884 calls recorded in New Zealand’s Southern Alps. Based on audio and visual spectrographic differences, these calls were categorised into seven distinct call types: the non-oscillating ‘screech’ contact call and ‘mew’; and the oscillating ‘trill’, ‘chatter’, ‘warble’ and ‘whistle’; and a hybrid ‘screech-trill’. Most of these calls contained aspects that were individually unique, in addition to potentially encoding for an individual’s sex and age. Additionally, for each recording, the sender’s previous and next calls were noted, as well as any response given by conspecifics. We found that the previous and next calls made by the sender were most often of the same type, and that the next most likely preceding and/or following call type was the screech call, a contact call which sounds like the ‘kee-ah’ from which the bird’s name derives. As a social bird capable of covering large distances over visually obstructive terrain, long distance contact calls may be of considerable importance for social cohesion. Contact calls allow kea to locate conspecifics and congregate in temporary groups for social activities. The most likely response to any given call was a screech, usually followed by the same type of call as the initial call made by the sender, although responses differed depending on the age of the caller. The exception was the warble, the kea’s play call, to which the most likely response was another warble. Being the most common call type, as well as the default response to another call, it appears that the ‘contagious’ screech contact call plays a central role in kea vocal communication and social cohesion

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In the picture-word interference task, naming responses are facilitated when a distractor word is orthographically and phonologically related to the depicted object as compared to an unrelated word. We used event-related functional magnetic resonance imaging (fMRI) to investigate the cerebral hemodynamic responses associated with this priming effect. Serial (or independent-stage) and interactive models of word production that explicitly account for picture-word interference effects assume that the locus of the effect is at the level of retrieving phonological codes, a role attributed recently to the left posterior superior temporal cortex (Wernicke's area). This assumption was tested by randomly presenting participants with trials from orthographically related and unrelated distractor conditions and acquiring image volumes coincident with the estimated peak hemodynamic response for each trial. Overt naming responses occurred in the absence of scanner noise, allowing reaction time data to be recorded. Analysis of this data confirmed the priming effect. Analysis of the fMRI data revealed blood oxygen level-dependent signal decreases in Wernicke's area and the right anterior temporal cortex, whereas signal increases were observed in the anterior cingulate, the right orbitomedial prefrontal, somatosensory, and inferior parietal cortices, and the occipital lobe. The results are interpreted as supporting the locus for the facilitation effect as assumed by both classes of theoretical model of word production. In addition, our results raise the possibilities that, counterintuitively, picture-word interference might be increased by the presentation of orthographically related distractors, due to competition introduced by activation of phonologically related word forms, and that this competition requires inhibitory processes to be resolved. The priming effect is therefore viewed as being sufficient to offset the increased interference. We conclude that information from functional imaging studies might be useful for constraining theoretical models of word production.

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Temporal and environmental variation in vocal activity can provide information on avian behaviour and call function not available to short-term experimental studies. Intersexual differences in this variation can provide insight into selection effects. Yet factors influencing vocal behaviour have not been assessed in many birds, even those monitored by acoustic methods. This applies to the New Zealand kiwi (Apterygidae), for which call censuses are used extensively in conservation monitoring, yet which have poorly understood acoustic ecology. We investigated little spotted kiwi Apteryx owenii vocal behaviour over 3 yr, measuring influences on vocal activity in both sexes from time of night, season, weather conditions and lunar cycle. We tested hypotheses that call rate variation reflects call function, foraging efficiency, historic predation risk and variability in sound transmission, and that there are inter-sexual differences in call function. Significant seasonal variation showed that vocalisations were important in kiwi reproduction, and inter-sexual synchronisation of call rates indicated that contact, pair-bonding or resource defence were key functions. All weather variables significantly affected call rates, with elevated calling during increased humidity and ground moisture indicating a relation between vocal activity and foraging conditions. A significant decrease in calling activity on cloudy nights, combined with no moonlight effect, suggests an impact of light pollution in this species. These influences on vocal activity provide insight into kiwi call function, have direct consequences for conservation monitoring of kiwi, and have wider implications in understanding vocal behaviour in a range of nocturnal birds

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This practice-led research investigated the negotiation processes informing effective models of transcultural collaboration. In a creative project interweaving the image-based physicality of the Japanese dance form of butoh with the traditional Korean vocal style of p'ansori, a series of creative development cycles were undertaken with a team of artists from Australia and Korea, culminating in Deluge, a work of physical theatre. The development of interventions at 'sites of transcultural potential' resulted in improvements to the negotiation of interpersonal relationships and assisted in the emergence of a productive working environment in transculturally collaborative artistic practice.

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Data on the influence of unilateral vocal fold paralysis on breathing, especially other than information obtained by spirometry, are relatively scarce. Even less is known about the effect of its treatment by vocal fold medialization. Consequently, there was a need to study the issue by combining multiple instruments capable of assessing airflow dynamics and voice. This need was emphasized by a recently developed medialization technique, autologous fascia injection; its effects on breathing have not previously been investigated. A cohort of ten patients with unilateral vocal fold paralysis was studied before and after autologous fascia injection by using flow-volume spirometry, body plethysmography and acoustic analysis of breathing and voice. Preoperative results were compared with those of ten healthy controls. A second cohort of 11 subjects with unilateral vocal fold paralysis was studied pre- and postoperatively by using flow-volume spirometry, impulse oscillometry, acoustic analysis of voice, voice handicap index and subjective assessment of dyspnoea. Preoperative peak inspiratory flow and specific airway conductance were significantly lower and airway resistance was significantly higher in the patients than in the healthy controls (78% vs. 107%, 73% vs. 116% and 182% vs. 125% of predicted; p = 0.004, p = 0.004 and p = 0.026, respectively). Patients had a higher root mean square of spectral power of tracheal sounds than controls, and three of them had wheezes as opposed to no wheezing in healthy subjects. Autologous fascia injection significantly improved acoustic parameters of the voice in both cohorts and voice handicap index in the latter cohort, indicating that this procedure successfully improved voice in unilateral vocal fold paralysis. Peak inspiratory flow decreased significantly as a consequence of this procedure (from 4.54 ± 1.68 l to 4.21 ± 1.26 l, p = 0.03, in pooled data of both cohorts), but no change occurred in the other variables of flow-volume spirometry, body-plethysmography and impulse oscillometry. Eight of the ten patients studied by acoustic analysis of breathing had wheezes after vocal fold medialization compared with only three patients before the procedure, and the numbers of wheezes per recorded inspirium and expirium increased significantly (from 0.02 to 0.42 and from 0.03 to 0.36; p = 0.028 and p = 0.043, respectively). In conclusion, unilateral vocal fold paralysis was observed to disturb forced breathing and also to cause some signs of disturbed tidal breathing. Findings of flow volume spirometry were consistent with variable extra-thoracic obstruction. Vocal fold medialization by autologous fascia injection improved the quality of the voice in patients with unilateral vocal fold paralysis, but also decreased peak inspiratory flow and induced wheezing during tidal breathing. However, these airflow changes did not appear to cause significant symptoms in patients.

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The purpose of this dissertation was to study the applicability of minced autologous fascia graft for injection laryngoplasty of unilateral vocal fold paralysis (UVFP). Permanence of augmentation and host versus graft tissue reactions were of special interest. The topic deals with phonosurgery, which is a subdivision of the Ear, Nose and Throat-speciality of medicine. UVFP results from an injury to the recurrent or the vagal nerve. The main symptom is a hoarse and weak voice. Surgery is warranted for patients in whom spontaneous reinnervation and a course of voice therapy fails to improve the voice. Injection laryngoplasty is a widespread surgical technique which aims to restore glottic closure by augmenting the atrophied vocal muscle, and also by turning the paralyzed vocal fold towards midline. Currently, there exists a great diversity of synthetic, xenologous, homologous, and autologous substances available for injection. An autologous graft is perfect in terms of biocompatibility. Free fascia grafts have been successfully used in the head and neck surgery for decades, but fascia had not been previously applied into the vocal fold. The fascia is harvested from the lateral thigh under local anesthesia and minced into paste by scissors. Injection of the vocal fold is performed in laryngomicroscopy under general anesthesia. Three series of clinical trials of injection laryngoplasty with autologous fascia (ILAF) for patients with UVFP were conducted at the Department of Otorhinolaryngology of the Helsinki University Central Hospital. The follow-up ranged from a few months to ten years. The aim was to document the vocal results and possible morbidity related to graft harvesting and vocal fold injection. To address the tissue reactions and the degree of reabsoprtion of the graft, an animal study with a follow-up ranging from 3 days to 12 months was performed at the National Laboratory Animal Center, University of Kuopio. Harvesting of the graft and injection was met with minor morbidity. Histological analysis of the vocal fold tissue showed that fascia was well tolerated. Although some resorption or compaction of the graft during the first months is evident, graft volume is maintained well. When injected deep and laterally into the vocalis muscle, the fascia graft allows normal vibration of the vocal fold mucosa to occur during phonation. Improvement of voice quality was seen in all series by multiple objective parameters of voice evaluation. However, the vocal results were poor in cases where the nerve trauma was severe, such as UVFP after chest surgery. ILAF is most suitable for correction of mild to moderate glottic gaps related to less severe nerve damage. Our results indicate that autologous fascia is a feasible and safe new injection material with good and stable vocal results. It offers a practical solution for surgeons who treat this complex issue.