The medial olivocochlear reflex (MOCR) is a brainstem-mediated reflex that reduces cochlear amplifier gain when elicited by sound. The MOCR may provide benefits such as protection from acoustic trauma and improved hearing in background noise. Measurement of MOCR effects may also have clinical applications. MOCR effects can be measured using transient-evoked otoacoustic emissions (TEOAEs), as amplitudes of TEOAEs are typically reduced during MOCR activation. The primary purpose of the current study was to quantify the repeatability of MOCR effects on TEOAEs because high repeatability in a healthy population is a necessary (but not sufficient) component of a clinically-useful test. A secondary purpose was to assess the relationship between MOCR strength and speech perception in noise. Twenty-one normal hearing subjects ages 18-30 participated. TEOAEs were elicited using 35 dB sensation level (SL) clicks. The MOCR was elicited using contralateral acoustic stimulation (CAS) consisting of 35 dB SL broadband noise. Sixteen measurements were made across a 5-week period (4 visits × 4 measurements per visit). TEOAEs were bandpass filtered in 1/6-octaves from 1-2 kHz. An individualized time-frequency analysis was used to select the largest TEOAE envelope peak within a restricted time analysis window. Responses were characterized as the complex ratio of TEOAEs obtained with versus without CAS. The statistical significance of effects was assessed. Results revealed generally high levels of stability across time, as assessed by the interquartile ranges of all results and as assessed by Cronbach's alpha. Four MOCR measurements appeared to be adequate to obtain a reliable baseline measurement. Individualized time-frequency analyses were also important for obtaining reliable measurements. However, several subjects showed stable baseline measurements but unusual patterns of variability at subsequent sessions. These changes did not appear to be the result of changes in auditory status, methodological issues, or equipment issues. No significant relationship was found between MOCR strength and speech perception in noise. Results suggest that MOCR measurements are stable in most subjects when using careful measurement and analysis methods, but that further work is needed to better characterize changes in MOCR and to validate the current methodology in a larger number of subjects.

O estresse hídrico afeta a produtividade das culturas, especialmente o milho, sendo de importância primordial os estudos de déficit hídrico aliados ao melhoramento genético, bem como o entendimento de mecanismos genéticos envolvidos com a tolerância à seca. Dessa forma o presente trabalho foi realizado com o objetivo de avaliar a divergência genética e o potencial da população de milho Pioneira Cerrado para a extração de linhagens e populações superiores. Além de estimar parâmetros genéticos das progênies de meios irmãos de milho, a fim de selecionar progênies de milhos adaptadas às condições edafoclimáticas doTocantins. O experimento foi conduzido em Gurupi -TO, na Fazenda Experimental da UFT, pertencente à Universidade Federal do Tocantins. Foram utilizadas 169 progênies de meios-irmãos da população de milho Cerrado (Grãos dentados), proveniente do programa de melhoramento da empresa Pioneira Ltda. As progênies foram avaliadas em experimento com duas repetições. O delineamento experimental utilizado foi o látice 13 x 13, com duas repetições. No primeiro capítulo foram consideradas as características altura deplanta, peso de espiga sem palha, peso de espiga com palha, comprimento de espiga e Produtividade de grãos para serem realizadas a análise de variância e teste de agrupamento de médias entre as progênies e posteriormente análise de seleção, utilizando índice baseados em ranks. Foram aplicadas intensidades de seleção de 22%, correspondendo ao número de trinta progênies. Observou-se efeito significativo das progênies de meios-irmãos de milho em todas as características. A média da população original foi de 1,80 m em altura de plantas, 0,183 kg em peso de espiga sem palha, 0,233 kg em peso de espiga com palha, 17,53 cm em comprimento de espiga e 6550,94 kg ha-1em produtividade. Enquanto na população selecionada o ganho de seleção nessas características foram de 12,49; 16,13; 11,96; 2,24 e 22,21%, respectivamente. No segundo capitulo foi utilizando as mesmas 169 progênies, contudo consideradas as características altura de plantas, altura de espiga, plantas quebradas, plantas acamadas, peso de espiga sem palha, peso de espiga com palha, comprimento de espiga, diâmetro de espiga, número de fileiras, número de grãos dor fileira e produtividade de grãos. No estudo da divergência genética entre às progênies foram realizadas as medidas de dissimilaridade, determinadas segundo o modelo de análise multivariada, o que permitiu a obtenção da matriz de dissimilaridade e covariância residual. Para tanto, foi utilizada a Distância Generalizada de Mahalanobis como medida de dissimilaridade e na obtenção dos grupos, utilizou-se o Método Hierárquico do Vizinho Mais Próximo e o Método de Otimização de Tocher. A análise de agrupamento pelo método de Tocher separou as progênies em sete grupos, sendo que no grupo I ficaram a maior parte das progênies geneticamente similares. Todas as características contribuíram na determinação da divergência genética, em maior ou menor proporção. No entanto, a produtividade de grãos foi a que mais contribuiu na dissimilaridade entre as progênies, devendo ser priorizada na seleção em programas de melhoramento. No agrupamento adotado pelo método hierárquico do vizinho mais próximo, mesmo estatisticamente similares observa-se pequenas distâncias entre as progênies. Essa informação é de suma importância dentro de programas de melhoramento e complementar aos resultados obtidos com a análise de Tocher. Com isso conclui-se que a população de milho Pioneira Cerrado demonstra divergência genética e potencial genético a ser utilizada em programas de melhoramento visando à obtenção de linhagens e populações superiores. As progênies de meios-irmãos de milho selecionadas no sul do Tocantins apresentam médias de ganhos satisfatórios em todas as características. / Water stress affects crop productivity, especially maize, with water deficit studies associated with genetic improvement as well as the understanding of genetic mechanisms involved in drought tolerance being of primary importance. Thus the present work was carried out with the objective of evaluating the genetic divergence and the potential of the PioneiraCerrado maize population for the extraction of superior strains and populations. In addition to estimating genetic parameters of progenies of half sibs of corn, in order to select progenies of maize adapted to the edaphoclimatic conditions of Tocantins. The experiment was conducted in Gurupi -TO, at the Experimental Farm of UFT, belonging to the Federal University of Tocantins. Sixty-six progenies of half-siblings of the PioneiraCerrado maize population (Serrated grains) were used, from the breeding program of the company Pioneira Ltda. Progenies were evaluated in two replicate experiments. The experimental design used was the 13 x 13 lattice, with two replicates. In thefirst chapter we considered the characteristics of plant height, spike weight without straw, spike weight with straw, ear length and grain yield to be performed the analysis of variance and test of grouping means between progenies and later analysis of Using indexes based on ranks. Selection intensities of 22% were applied, corresponding to the number of thirty progenies. Significant effect of corn half-sib progenies on all traits was observed. The mean of the original population was 1.80 m in height of plants, 0.183 kg in weight of spike without straw, 0.233 kg in weight of spike with straw, 17.53 cm in length of spike and 6550.94 kg ha-1 Productivity. While in the selected population the selection gain in these characteristics was 12.49; 16.13; 11.96; 2.24 and 22.21%, respectively. In the second chapter, the same 169 progenies were used, however, considering the height characteristics of plants, height of spike, broken plants, bedded plants, tang weight without straw, tang weight with straw, ear length, ear diameter, number of rows, number of grain row pain and grain yield. In the study of the genetic divergence between the progenies, the dissimilarity measures were determined, according to the multivariate analysis model, which allowed to obtain the matrixof dissimilarity and residual covariance. For this, the Generalized Distance of Mahalanobis was used as a measure of dissimilarity and in obtaining the groups, we used the Hierarchical Neighboring Neighbor Method and the Tocher Optimization Method. The cluster analysis by the Tocher method separated the progenies into seven groups, and in group I most of the genetically similar progenies remained. All characteristics contributed to the determination of genetic divergence, to a greater or lesser extent. However, grain yield was the one that contributed the most to the dissimilarity among the progenies, and should be prioritized in the selection in breeding programs. In the grouping adopted by the hierarchical method of the nearest neighbor, even statistically similar, small distances between the progenies are observed. This information is of utmost importance within breeding programs and to complement the results obtained with the Tocher analysis. With this, it can be concluded that the PioneiraCerrado maize population shows genetic divergence and genetic potential to be used in breeding programs aimed at obtaining superior strains and populations. The progenies of selected half-sibs of maize in southern Tocantins present satisfactory averages of all traits.

An oceanographic buoy with 10 atmospheric and oceanographic instruments was deployed in Clayoquot Sound on the west coast of Canada in 2007. The high-resolution time series was used to monitor the fine-scale variability in the coastal ocean. Over 700 CTD profiles measuring temperature, salinity and chlorophyll fluorescence made in the region of the buoy were used to relate the buoy data to spatial patterns. Analysis showed that large-scale upwelling in combination with the localized winds and tidal currents affect water properties at time scales of hours to days. At low tide the buoy represented inland water and at high tide the buoy represented offshore water. Both the buoy data and CTD profiles measured a strong offshore/onshore gradient. For temperature the gradient depended on the direction of the wind, salinity was always higher offshore compared to onshore, and the chlorophyll fluorescence was higher onshore in the early spring and higher offshore for the rest of the time series. The fine scale temporal resolution of the buoy was able to capture the variability measured by the CTD profiles in a 40km2 area. This work shows the importance of making high-resolution temporal measurements in the coastal ocean. However, these types of moorings also require frequent maintenance. In Clayoquot Sound, the optical sensors needed to be cleaned every 4-6 days.

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