Macrodon ancylodon é um cienídeo demersal distribuído desde a Venezuela até a costa Nordeste do Brasil, sendo um dos principais recursos pesqueiros da costa Norte brasileira. Este trabalho estimou os parâmetros de crescimento, através de métodos diretos e indiretos, assim como descreveu os aspectos reprodutivos utilizando análises macro- e microscópicas dos ovários. As amostras foram obtidas no período de 1998 a 2001, provenientes de atividades pesqueiras industriais e artesanais na costa Norte. Para o estudo do crescimento, pelo método direto, foram realizados cortes transversais dos otólitos sagittae, e, para o método indireto, distribuições modais da freqüência de comprimento. Os parâmetros de crescimento para duas coortes encontradas foram: coorte 1) L¥= 47,4 cm, k= 0,42 e to= -0,3442; coorte 2) L¥= 46,8 cm, k= 0,44 e to= - 0,3302, nascidas em junho e dezembro, respectivamente. As avaliações qualitativas e quantitativas das gônadas indicaram que o período de desova é prolongado, com picos em julho-agosto e dezembro-fevereiro, coincidindo com o final do período de transição do regime de pluviosidade. As fêmeas atingem o comprimento médio de início de primeira maturação gonadal (L50) aos 25,08 cm, com 1,5 anos de idade, e todas estão participando do processo reprodutivo ao atingir 34,00 cm (L100). O estudo histológico indicou existência de estádios maturacionais intermediários aos da classificação macroscópica bem como erros na identificação macroscópica do estádio \"B\", da ordem de 40%. / Macrodon ancylodon is a demersal marine Sciaenidae largely distributed along the Brazilian coast. It is one of the major fisheries resources, mainly in the Northern and Southern regions of the Brazil. This work aims to estimate the growth parameters trough direct and indirect methods as well as estimate the reproductive aspects trough macroscopic and microscopic analyses of the gonads. The samples were obtained in the 1998-2001 period, derived from industrial and artisanal fishing activities that work along the Northern Brazilian coast. In order to conduct the growth study by the direct method, transversal sections were employed over the otolith sagitta. By the indirect method the length frequency modal distribution were observed during the period. The histological study was conducted on macroscopically classified females \"semi-mature\". It was verified the variation of the gonadosomatic relationship, the variation of the condition factor and the frequencies of the maturation stages. The growth parameters couldn\'t be estimated due to the absence of modal distribution in the length frequency and because the otolith sections were unreadable. The macroscopic valuation indicate a prolonged spawning season and has peaks in June-July and November-December, which coincide with the transition of the pluviometric period. The histological study indicate that the female enter this stages \"semi-mature\" more than once per cycle. The female reach the first maturation mean length (L50) of 25,08 cm and all of them participate in the reproductable process when reach 34,00 cm (L100).

Estudos sobre a análise populacional da abrótea-de-profundidade, Urophycis mystacea, uma ferramenta importante para a gestão de estoques, nunca haviam sido realizados. Na presente dissertação, através da análise da distribuição em comprimentos de exemplares coletados ao longo da região sudeste-sul do Brasil, da análise quali-quantitativa das características morfológicas e morfométricas dos otólitos sagittae e da análise das razões de isótopos estáveis dos mesmos, foi avaliada a homogeneidade do estoque, que constitui importante recurso pesqueiro na região. Para as análises, a região entre o cabo de São Tomé e o Chuí foi dividida em três áreas. As análises morfológicas foram feitas seguindo metodologia de TUSET et. al (2008) e ASSIS (2002), usando quinze feições da sagittae. O teste qui-quadrado foi aplicado para verificar a homogeneidade da distribuição dos caracteres em relação a ontogenia. As análises morfométricas foram realizadas em um estereomicroscópio, com otólitos de peixes da faixa entre 300 e 499 mm de comprimento total, comum às três áreas. Foram obtidas variáveis morfométricas (Co, Ao, Eo, Po, Ar e Pe) e calculadas relações morfométricas e os indicadores de forma. Testes estatísticos foram aplicados para verificar diferenças dos caracteres entre as áreas pré-estabelecidas. Para a análise isotópica foram análizados dez otólitos por área, de peixes cujos comprimentos totais estavam entre 300 e 499 mm, sendo obtidos as razoes isotópicas de O18 e C13, em espectrômetro de massa de cinco núcleos e cinco otólitos. Os resultados indicaram não haver variação morfológica dos otólitos nas três áreas, porem os testes morfométricos mostraram grande variação sazonal e a presença de dois \"morfotipos\". Os testes com isótopos estáveis mostraram que os peixes nascem em locais diferentes e se misturam ao longo da vida. / Studies on the population analysis of the deep-hake, Urophycis mystacea, an important tool for stock management, had never been made. In the present study, by analyzing the distribution of lengths in specimens collected over the area, qualitative and quantitative analysis of morphological and morphometric characteristics of otolith sagittae and analysis of isotopic ratios of stable isotopes of these structures, evaluated the homogeneity of the stock, which is an important fishery resource in the southeast-south Brazil.For the analyzes, the south-east coast was divided into three regions. Morphological analyzes were made following the methodology Tuset et. al (2008) and ASSIS (2002), using fifteen features of the otoliths sagittae a chi-square test was used to verify the homogeneity of the distribution of characters along the ontogeny. The morphometric analyzes were performed under a stereomicroscope with fish otoliths belonging to the range between 300 and 499 mm in total length. Morphometric variables were obtained as well as morphometric relationships and shape indicators. Statistical tests were applied on the characters pre-established to check for differences between the regions. Isotopic analysis were done for ten otoliths by region, whose total lengths of fish were between 300 and 499 mm. Five otoliths were taken for analysis of the core and five for the analysis of the whole otolith obtaing the oxygen isotope ratio of 18 oxigen and 13 carbon in a mass spectrometer.The results indicated that there was no morphological variation on the otoliths of the three regions; however the morphometric analysis showed strong seasonal variation and the presence of two \"morphotypes\" otoliths in the region. Tests with stable isotopes suggest that fish born in different places and mix throughout their life.

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The vestibular system senses changes in head position and is responsible for the brain’s perception of verticality. Vestibular dysfunction is caused by deficits in the semicircular canals and/or otolith end-organs with resulting symptoms including dizziness, vertigo, and unsteadiness. Current vestibular rehabilitation focuses on compensation of the semicircular canal-mediated vestibulo-ocular reflex through gaze and balance exercises. Little is known about rehabilitation of otolith organ function, yet research findings suggest that fall risk may be related to otolith dysfunction. A recent case study demonstrated improvement of vertical perception and balance following off-axis rotation in a rotary chair, showing that such stimulation may be useful for compensation of otolith organ dysfunction. The purpose of our research was to further investigate off-axis rotation as a possible treatment method by evaluating subjective visual vertical (SVV) in healthy controls. Two distance parameters (3.5 cm off-axis and 7.0 cm off-axis) were applied to the rotary chair, with results measured through the SVV test, visual analog scales (VAS), and the balance tilt test (BTT). The magnitude of SVV shift following off-axis rotation was measured in both the 3.5 cm and 7.0 cm off-axis experiments. The greater distance parameter (7.0 cm) did not increase SVV shift magnitude more than the 3.5 cm parameter; yet, resulted in greater symptom intensity as measured through the VAS. These findings led to the conclusion that a distance parameter of 3.5 cm off-axis is optimal for stimulating the otolith organs. This discovery may be helpful in future research utilizing off-axis rotation as a possible treatment method for vestibular patients suffering from otolith dysfunction.

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The otolith organs (the saccule and utricle) are located in the inner ear and sense linear acceleration, head tilt, and gravity. Recently, the vestibular evoked myogenic potential (VEMP) and the subjective visual vertical (SVV) have been described as clinical tests for otolith function. VEMPs are short latency electromyograms (EMG) evoked by high-level acoustic and vibratory stimuli recorded from surface electrodes over the tonically contracted SCM muscles (cervical VEMP) or extra-ocular muscles (ocular VEMP). The SVV is a psychophysical measure of the angle between perceptual vertical and true (gravitational) vertical and can be measured during unilateral centrifugation (off-axis eccentric rotation). The purpose of this paper is to discuss the clinical use and recent developments of the cervical VEMP, ocular VEMP, and SVV as tests of saccular and utricular function.

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