<div>Halogen chemistry in the Arctic boundary layer catalytically destroys O3 and impacts the chemical lifetimes of hydrocarbons, the HOx-NOx cycle, and atmospheric mercury. While many advances have been made in the last several decades in understanding the sources, sinks, and recycling pathways of halogens in the Arctic there are still many unknowns. Previous studies have shown that Br2, BrCl and Cl2 are produced photochemically in the Arctic tundra snowpack, but the magnitude of this production is still poorly understood. Additionally, while there have been suggestions that the tundra snowpack should also produce I2, there have been no previous measurements of I2 in the Arctic. The lack of measurements of the halogen production capacity of Arctic snowpacks has left the community to rely on one-dimensional modeling to estimate the impact of snowpack-derived halogen chemistry on the Arctic atmosphere. Because modeling is inherently dependent on understanding recycling mechanisms, mixing processes, and sinks this leaves the effect of halogens on atmospheric chemistry in the Arctic highly uncertain.</div><div><br></div><div>This work describes efforts to address these uncertainties through measurements made during two field campaigns in Utqiaġvik (formerly Barrow), Alaska in January – February 2014, and February – May 2016. The first measurements of I2 in the Arctic, both in the snowpack interstitial air, and in the air above the snowpack demonstrate that iodine chemistry is active in the Arctic atmosphere, and that I2 is produced photochemically in the tundra snowpack. The effects of active iodine chemistry on both O3 and bromine chemistry is examined through zero- and one dimensional modeling. The first speciated measurements of snowpack phase iodine reveal that much like previous reports of iodine enriched aerosols, the Arctic snowpack is highly enriched in iodine. Vertical profiles of I- in the snowpack suggest that there is a consistent, non-radiation dependent source of iodine to the Arctic environment. It seems likely that this source is transport of iodine-enriched aerosols from the mid-latitudes. However, unlike the Antarctic, and previous</div><div>observations in the mid-latitudes, most Arctic snowpack phase iodine is inorganic, which may contradict transport from the mid-latitudes as a source. One-dimensional modeling was also utilized, in conjunction with the first vertical profile measurements of Br2 and Cl2 between 1 and</div><div>7 m above the snowpack surface to examine the community’s understanding of recycling mechanisms, mixing, sources, and sinks of halogens in the Arctic Atmosphere.</div>

Phenotyping in multi-environment trials (MET) plays an important role to access the differential response of maize hybrids across target breeding regions due to genotype by environment (GxE) interaction. In this context, an effective model of genomic selection (GS) to predict the performance of untested hybrids in MET is essential to maximize genetic gains and to efficiently allocated the breeding programs\' budget. Therefore, the goals of this study were (i) to evaluate the predictive accuracies of GBLUP (Genomic Best Linear Unbiased Prediction) models to predict grain yield performance of unobserved tropical maize single-cross hybrids, using models that consider GxE interaction by fitting a factor analytic (FA) variance-covariance (VCOV) structure, and (ii) to investigate the usefulness of genomic relationship information in combination with different VCOV for genetics and residuals effects, under different levels of unbalanced environments. Predictions were performed for two situations: (CV1) untested hybrids, and (CV2) hybrids evaluated in some environments but missing in others. Phenotypic data of grain yield was measured in 156 maize single-cross hybrids at 12 environments. Hybrids genotypes were inferred based on their parents (inbred lines) via SNP (single nucleotide polymorphism) markers obtained from GBS (genotypingby- sequencing). The procedures and models applied in this study can be easily extended to other crops in which MET plays an important role in the breeding process. / A fenotipagem em ensaios de múltiplos ambientes (MET) tem papel importante para acessar a resposta diferencial de híbridos de milho em diferentes regiões alvo de melhoramento, o que se deve a interação genótipos por ambientes (GxE). Neste contexto, um modelo efetivo de seleção genômica (GS) para predição do desempenho de híbridos não avaliados em MET é essencial para maximizar os ganhos genéticos e alocar eficientemente o orçamento dos programas de melhoramento. Desta forma, os objetivos deste estudo foram (i) avaliar as acurácias preditivas de modelos GBLUP (do inglês, Genomic Best Linear Unbiased Prediction) na predição da produtividade de grãos de híbridos simples de milho tropical não avaliados, usando modelos genético-estatísticos que levam em consideração a interação GxE através de uma estrutura de variância-covariância (VCOV) do tipo fator analítico (FA) e (ii) investigar a utilidade da matriz de parentesco realizada em combinação com diferentes estruturas de VCOV para efeitos genéticos e de resíduos em diferentes níveis de ambientes em desbalanceamento. As predições foram realizadas em duas situações: (CV1) híbridos não avaliados em nenhum ambiente e (CV2) híbridos avaliados em alguns ambientes e em outros não. Foram fenotipados 156 híbridos simples de milho em 12 ambientes para a característica produtividade de grãos. O genótipo dos híbridos foi inferido com base nas informações de marcadores SNP (do inglês, single nucleotide polymorphism) das linhagens parentais, obtidos via GBS (do inglês, genotyping-by-sequencing). Os procedimentos e modelos utilizados neste estudo podem ser facilmente estendidos a outras culturas em que MET desempenha um papel importante no processo de melhoramento.

Dentro da biologia evolutiva, uma das questões centrais é a compreensão de como os processos evolutivos, em particular a seleção e o acaso (deriva genética) moldaram a diversidade obervada nos organismos. Dentro deste contexto, a utilização de abordagens como a integração morfológica e a genética quantitativa nos fornecem poderosas ferramentas. Enquanto a primeira descreve os padrões de relação entre caracteres e testa hipóteses sobre as relações de desenvolvimento e/ou funções subjacentes, a segunda possui ferramentas para investigar as forças que podem ter gerado os fenótipos atuais. Utilizando como modelo de estudo os gêneros de marsupiais da Ordem Didelphimorphia, analisei a evolução morfológica craniana unindo estas duas linhas de pesquisa. Central a genética quantitativa está a matriz de covariância genética (G) que descreve a porção da variância que é efetivamente herdada (no sentido de transmissão de valor entre gerações) e conseqüentemente serve como substrato à seleção. Apesar de ter sido desenvolvida inicialmente para estudos em escala microevolutiva, o arsenal matemático da genética quantitativa pode ser estendida a escalas macroevolutivas caso a matriz G permaneça relativamente estável. Entretanto, como a estimativa de uma matriz G requer um número grande de espécimes aparentados e com genealogia conhecida, utilizei ao longo deste trabalho sua correspondente fenotípica (P). Desta forma, no primeiro capítulo demonstrei a similaridade das matrizes de covariância e correlação P dos marsupiais Didelphimorphia. Em contrapartida, as magnitudes de integração morfológica, que medem o grau de associação entre os caracteres, se mostraram mais variáveis dentro do grupo. A história evolutiva (filogenia) e as distâncias morfológicas entre os gêneros não parecem ter tido influência sobre os padrões nem as magnitudes, já que não se correlacionaram significativamente a eles. No segundo capítulo, estendi estas análises para os gêneros ao longo do seu desenvolvimento e novamente os padrões se mostraram semelhantes, tanto quando comparei a ontogenia de um único gênero, quando analisei diferentes gêneros para diferentes classes etárias. Em contrapartida, as magnitudes de integração se mostraram mais variáveis, com uma tendência a diminuírem com o aumento da idade. Por conta destes resultados, comparei as matrizes de correlação empíricas com matrizes teóricas que expressam hipóteses de modularidade baseadas no desenvolvimento/função compartilhada pelas regiões do crânio. Testei para similaridade das duas regiões principais (face e neurocrânio), cinco sub-regiões (base e abóboda craniana, oral, nasal e zigomático), uma matriz 198 de integração somática (caracteres neurais vs. faciais) e uma de integração total, concatenando as cinco sub-regiões. Foram encontradas somente correlações significativas para as regiões da face e suas sub-regiões nasal e oral. Apesar das variações nas magnitudes de integração observadas nestes dois primeiros capítulos, as respostas evolutivas obtidas para estes gêneros foram todas muito similares. Este resultado, associado a constatação de que grande parte da variação entre os espécimes é devida ao tamanho, ou variações de forma associadas a ele (alometria), me levaram a analisar as conseqüências evolutivas associadas a estas variações alométricas. Assim, no terceiro capítulo analisei as direções de resposta à seleção simulada antes e após a remoção do tamanho. Variações alométricas exercem forte influência sobre estes crânios tornando-os muito integrados morfologicamente, ou seja, a percepção dos módulos que os compõem é muito difícil (baixa modularidade). Isto se reflete em uma maior variação ao longo da linha de menor resistência evolutiva (que resume o eixo de maior variação disponível entre os espécimes), já que os módulos não podem responder a seleção de forma independente (alta integração morfológica). Em marsupiais, esta linha é está alinhada na direção de variações de tamanho. Desta forma, não importa em que direção a seleção esteja atuando, as respostas evolutivas serão usualmente na direção desta linha de menor resistência e conseqüentemente de tamanho. Uma vez que o tamanho é removido, as magnitudes de integração diminuem e a modularidade do crânio aumenta. Por conseguinte, ele passa a ser capaz de responder à seleção em uma gama maior de direções porque aumenta também a relativa independência destes módulos em relação aos demais. Como estes resultados indicam que variações entre os Didelphimorphia são direcionadas a variações no tamanho, devido justamente às restrições impostas pela linha de menor resistência evolutiva, analisei as trajetórias ontegenéticas de dois gêneros irmãos, Didelphis e Philander, separando os efeitos da forma e tamanho nesta diversificação. Para tanto empreguei análises de morfometria tradicional, morfométrica e análises de coeficientes alométricos que apontaram para uma maior diferenciação no tamanho entre eles. Apesar da similaridade entre as trajetórias ontogenéticas destes dois gêneros, espécimes de Didelphis nascem maiores e crescem por mais tempo, como indicado pela sua trajetória mais longa. / One of the central goals in evolutionary biology is related to how evolutionary processes, mainly natural selection and genetic drift, shaped living organisms. The combined use of Morphologial Integration and Quantitative Genetics give us powerful tools to accomplish this goal. Morphological Integration is concerned of how characters are related, as well as their underlying genetics/developmental relationship, while Quantitative Genetics have methodologies designed to explore the phenotypic forces underlying diversity among organisms. Using Didelphimorphia marsupials as a study group, I combined these two approaches to study its morphologic cranial diversification. In Quantitative Genetics, the genetic additive covariance matrix (G) resume the genetic variation underlying resemblance among relatives, which is the portion of the variance responsive to selection. Initially developed to microevolutionary scale studies, it can be extended to a macroevolutionary scale if it remains relatively similar in that time scale. However, as G matrix estimations require a huge number of related specimens with known genealogy, I used its phenotypic (P) counterpart which was more easily obtained. In the first chapter I showed high similarities among Didelphimorphia marsupials covariance and correlation P matrices. On the other hand, integration magnitudes (which measure the average correlation among traits) vary among taxa. Neither phylogeny nor morphologic distances showed any association with the similarity in patterns and magnitudes of integration. In the second chapter, I did these same analyses, but throughout genera ontogeny. Again, there was a high similarity among taxa in patterns of integration, both when I analyzed the ontogeny for each genus separately or against each other (at different age class). Morphological integration magnitudes showed the same variation obtained for adults, with a tendency to decrease at older ages. Taking these results into account, I compared the phenotypic correlation matrices to theoretical matrices, based on hypotheses of shared developmental and functional units. I searched for modularity in the two main skull regions (face and neurocranium) and five sub regions (cranium base and vault, face, nasal, and oral). I also looked for modularity concerning somatic development (Neurocranium vs. Face) and total modularity, as the 200 summation of the five sub-regions. Only Face and its sub-regions nasal and oral, showed significant correlations to the phenotypic genera matrices. Despite integration magnitude differences, all evolutionary responses produced by taxa were highly similar. These results, combined with a huge size variation (or size related variation - allometry) across taxa, lead me to search for the evolutionary consequences due to size variation. In the third chapter, I compared evolutionary response directions produce by each genera matrices before and after size removal under a random selection simulation. Allometry strongly affect these skulls, turning them into highly integrated structures with lower modularity (skull modules are not easily distinguished). Because of this, modules cannot evolve relatively independent of other modules and evolutionary responses will strongly affect the whole cranium. This is related to the variation along the lines of least evolutionary resistance. This line is the multivariate direction of greatest genetic or phenotypic variation (the combination of a suite of traits that displays the maximum within-population variance). In Didelphimorphia marsupials, this line is aligned with size variation and regardless the selection direction, evolutionary change is usually aligned to this least resistance line. The removal of size variation diminish the magnitude of integration while increases modularity. Consequently, skulls become able to respond to selection in more directions as modules become relatively more independent of each other. In the last chapter I compared size and shape differences between ontogenetic trajectories of two sister genera Didelphis and Philander. Using traditional and geometric morphometric analysis plus allometric coefficient analysis, I could show that bigger differences between them are size related. Despite similarities, ontogenetic trajectory in Didelphis is longer, leading to bigger specimens.

Nesta dissertação, foi utilizada a técnica SIFT (Scale Invariant Feature Transform) para o reconhecimento de imagens da área dos olhos (região periorbital). Foi implementada uma classificação das imagens em subgrupos internos ao banco de dados, utilizando-se das informações estatísticas provenientes dos padrões invariantes produzidos pela técnica SIFT. Procedeu-se a uma busca categorizada pelo banco de dados, ao invés da procura de um determinado padrão apresentado, através da comparação deste com cada padrão presente no banco de dados. A tais padrões foi aplicada uma abordagem estatística, através da geração da matriz de covariâncias dos padrões gerados, sendo esta utilizada para a categorização, tendo por base uma rede neural híbrida. A rede neural classifica e categoriza o banco de dados de imagens, criando uma topologia de busca. Foram obtidos resultados corretos de classificação de 76,3% pela rede neural híbrida, sendo que um algoritmo auxiliar determina uma hierarquia de busca, onde, ocorrendo uma errônea classificação, a busca segue em grupos de pesquisas mais prováveis.

Submitted by (edna.saturno@ufrpe.br) on 2017-02-07T12:40:31Z No. of bitstreams: 1 Ana Lia Camposa Quaggio.pdf: 1430515 bytes, checksum: 68e33f51877fa5eba2d7e0997b3e6520 (MD5) / Made available in DSpace on 2017-02-07T12:40:31Z (GMT). No. of bitstreams: 1 Ana Lia Camposa Quaggio.pdf: 1430515 bytes, checksum: 68e33f51877fa5eba2d7e0997b3e6520 (MD5) Previous issue date: 2010-02-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Since the 50’s, Xiphias gladius (Linnaeus, 1758) has been captured along the Brazilian coast by surface longliners. This is the second most important target species for the tuna fleet based in Itajaí, Santa Catarina State, after the blue-shark, Prionace glauca (Linnaeus, 1758). The study was based on data from sea observers, log books and carcass ladings of Xiphias gladius, Linnaeus, 1758) from the pelagic longline fleet based in Itajaí, which operated in the southwest Atlantic. Covariance models were fit to the catches (weight, kg) of swordfish and the effects used were: (1) the years 1997, 1998, 2001, 2002 e 2007 (2) lunar phases and (3) seasons. The covariate was fishing effort (hooks). The highest moon catches occurred on the first quarter moon and during wintertime. The Mantel-Haenszel procedure was used to test the hook selectivity and showed that the type “J” hook (J 9/0 10º offset), traditionally used by the fleet, have 1.2 more chances of catching Xiphias gladius than the “circle” hook (18/0 10º offset), used as an optinal device to reduce sea turtle bycatch. The M-H test showed that the J hook has 1,2 more chances of catching Xiphias gladius than the circle hook. The conversion of individual carcass weights (kg) to total length (cm) for the years 2000 to 2002 showed that 66% of the catches were sub-adults. / O espadarte, Xiphias gladius (Linnaeus, 1758), vem sendo capturado na costa brasileira desde os anos 50 pelo espinhel-de-superfície. Esta é a segunda mais importante espécie-alvo da frota atuneira sediada em Itajaí (SC), ficando atrás apenas do tubarão-azul, Prionace glauca (Linnaeus, 1758). No presente estudo foram analisados os dados obtidos para esta espécie através de observadores, mapas de bordo e fichas de desembarque de carcaças de X. gladius para a frota de espinhel-de-superfície sediada em Itajaí (SC) e atuante no Atlântico sudoeste. Foram elaborados modelos de análise de covariância (ANCOVA) e aplicados aos dados de captura (peso em kg) do espadarte, tendo como efeitos: (1) os anos de 1997, 1998, 2001, 2002 e 2007 (2) as fases lunares e (3) as épocas do ano. A covariável foi o esforço de pesca (n° de anzóis). As maiores médias de captura ocorreram durante as fases de lua crescente e no inverno. O procedimento estatístico de Mantel-Haenszel teste foi utilizado para comparar as capturas do espadarte no anzol tipo “Jota” (9/0 10º offset) comumente utilizado pela frota espinheleira com o anzol tipo “circular” (18/0 10ºoffset), este último oferecido como alternativa mitigadora à captura de tartarugas marinhas. O teste M-H indicou que o anzol “Jota” apresentou 1,2 mais chances de capturar Xiphias gladius que no “circular”. A conversão dos pesos individuais das carcaças (kg) em comprimentos totais (cm), referentes aos anos de 2000 a 2002, indicou que 66% das capturas foram de sub-adultos, ao longo de todo o ano.

Because the way mothers play with their children may have significant impacts on children's social, cognitive, and linguistic development, researchers have become interested in potential predictors of maternal play. In the present study, 40 mother–infant dyads were followed from child age 5–20 months. Five-month habituation rate and 13 and 20 month temperamental difficulty were found to be predictive of maternal play quality at 20 months. The most parsimonious theoretical model was one in which habituation was mediated by temperamental difficulty in predicting mother play. Consistent with prior speculation in the literature, these data support the possibility that mothers adjust some aspects of their play behaviors to fit their children's cognitive and temperamental capabilities.

A linear covariance analysis is conducted to assess closed-loop guidance, navigation, and control system (GN&C) performance of the Altair vehicle during lunar powered descent. Guidance algorithms designed for lunar landing are presented and incorporated into the closed-loop covariance equations. Navigation-based event triggering is also included in the covariance formulation to trigger maneuvers and control dispersions. Several navigation and guidance trade studies are presented demonstrating the influence of triggering and guidance and study parameters on the vehicle GN&C performance.

This thesis concerns the development, estimation and investigation of a general anisotropic spatial correlation function, within model-based geostatistics, expressed as a Gaussian linear mixed model, and estimated using residual maximum likelihood (REML). The Matern correlation function is attractive because of its parameter which controls smoothness of the spatial process, and which can be estimated from the data. This function is combined with geometric anisotropy, with an extension permitting different distance metrics, forming a flexible spatial covariance model which incorporates as special cases many infinite- range spatial covariance functions in common use. Derivatives of the residual log-likelihood with respect to the four correlation-model parameters are derived, and the REML algorithm coded in Splus for testing and refinement as a precursor to its implementation into the software ASReml, with additional generality of linear mixed models. Suggestions are given regarding initial values for the estimation. A residual likelihood ratio test for anisotropy is also developed and investigated. Application to three soil-based examples reveals that anisotropy does occur in practice, and that this technique is able to fit covariance models previously unavailable or inaccessible. Simulations of isotropic and anisotropic data with and without a nugget effect reveal the following principal points. Inclusion of some closely-spaced locations greatly improves estimation, particularly of the Matern smoothness parameter, and of the nugget variance when present. The presence of geometric anisotropy does not adversely affect parameter estimation. Presence of a nugget effect introduces greater uncertainty into the parameter estimates, most dramatically for the smoothness parameter, and also increases the chance of non-convergence and decreases the power of the test for anisotropy. Estimation is more difficult with very “unsmooth" processes (Matern smoothness parameter 0.1 or 0.25) | non- convergence is more likely and estimates are less precise and/or more biased. However it is still often possible to fit the full model including both anisotropy and nugget effect using REML with as few as 100 observations. Additional simulations involving model misspecification reveal that ignoring anisotropy when it is present can substantially increase the mean squared error of prediction, but overfitting by attempting to model anisotropy when it is absent is less damaging. Further, plug-in estimates of prediction error variance are reasonable estimates of the actual mean squared error of prediction, regardless of the model fitted, weakening the argument requiring Bayesian approaches to properly allow for uncertainty in the parameter estimates when estimating prediction error variance. The most valuable outcome of this research is the implementation of an anisotropic Matern correlation function in ASReml, including the full generality of Gaussian linear mixed models which permits additional fixed and random effects, making publicly available the facility to fit, via REML estimation, a much wider range of variance models than has previously been readily accessible. This greatly increases the probability and ease with which a well-fitting covariance model can be found for a spatial data set, thus contributing to improved geostatistical spatial analysis. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1297562 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2007

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<p>Forest quantification methods have evolved from a simple graphical approach to complex regression models with stochastic structural components. Currently, mixed effects models methodology is receiving attention in the forestry literature. However, the review work (Paper I) indicates a tendency to overlook appropriate covariance structures in the NLME modeling process.</p><p>A nonlinear mixed effects modeling process is demonstrated in Paper II using Cupressus lustanica tree merchantable volume data and compared several models with and without covariance structures. For simplicity and clarity of the nonlinear mixed effects modeling, four phases of modeling were introduced. The nonlinear mixed effects model for C. lustanica tree merchantable volume with the covariance structures for both the random effects and within group errors has shown a significant improvement over the model with simplified covariance matrix. However, this statistical significance has little to explain in the prediction performance of the model.</p><p>In Paper III, using several performance indicator statistics, tree taper models were compared in an effort to propose the best model for the forest management and planning purpose of the C. lustanica plantations. Kozak's (1988) tree taper model was found to be the best for estimating C. lustanica taper profile.</p><p>Based on the Kozak (1988) tree taper model, a Ds optimal experimental design study is carried out in Paper IV. In this study, a Ds-optimal (sub) replication free design is suggested for the Kozak (1988) tree taper model.</p>