Armazenamento das sementes associado a embebição, hormônios e 'KNO IND. 3' na germinação e desenvolvimento inicial de mudas de Passiflora alata Dryander

Pós-graduação em Agronomia - FEIS

Curvas de progresso de doenças foliares do milho, sob diferentes tratamentos fungicidas

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Heterogeneidade Estrutural na Produtividade das Firmas Brasileiras

O objetivo deste trabalho é analisar uma das dimensões da heterogeneidade produtiva, estudando a distribuição das firmas entre diferentes estratos de produtividade na indústria de transformação, assim como a dinâmica de transição destas firmas dentro e entre estes estratos. Com esse objetivo, identificam-se, em primeiro lugar, grupos ou estratos em que a produtividade é marcadamente diferente, a partir de instrumental de cluster k-means. Posteriormente, por meio de um modelo probit ordenado, estuda-se a probabilidade de permanência das firmas nos diferentes estratos de produtividade, determinada por variáveis associadas ao progresso técnico, participação no comércio exterior, difusão e absorção de tecnologia e políticas públicas. Esta análise se faz em duas partes: em primeiro lugar para o total das empresas e incluindo os efeitos marginais para cada um dos clusters encontrados. Em segundo lugar, separando as firmas em quatro grupos, definidos pela intensidade tecnológica do processo produtivo. O estudo abrange o período 2000-2008, com uma base de dados de mais de 14.000 firmas brasileiras com 30 ou mais trabalhadores. O objetivo do trabalho é testar em que medida a heterogeneidade produtiva é um fenômeno persistente no tempo, em que medida ela tende a aumentar ou diminuir e em que medida é possível esperar um processo de transição entre estratos ou grupos no qual os grupos de mais alta produtividade elevam seu peso no total.

Estudos histopatológicos e ciclos biológicos de Meloidogyne mayaguensis e M. javanica em tomateiros com gene Mi

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Virulência de Thyrinteina arnobia virus (TaV) e de Bacillus thuringiensis à Thyrinteina arnobia (Lepidoptera: Geometridae): efeito da temperatura no desenvolvimento das lagartas e do pH da calda de pulverização

Pós-graduação em Agronomia (Proteção de Plantas) - FCA

Influência do processamento de próteses totais superiores em função da profundidade do palato: análise da movimentação dos dentes artificiais por computação gráfica

Pós-graduação em Odontologia - FOA

Avaliação da estabilidade de cor após o envelhecimento acelerado de dois silicones pigmentados ou não para uso em próteses faciais

Pós-graduação em Odontologia - FOA

Efeito da desinfecção química e do envelhecimento acelerado sobre a, estabilidade dimensional, reprodução e manutenção de detalhes, dureza “Shore A”, deterioração e estabilidade de cor de silicone para próteses faciais com distintas pigmentações

Pós-graduação em Odontologia - FOA

Efeito da fadiga cíclica na resistência, crescimento subcrítico de trincas e tempo de vida de cerâmicas a base de alumina infiltradas por vidro

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Práticas educativas de genitores e professoras e repertório comportamental de crianças do ensino fundamental: estudos de caso

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Modelos duplo sigmoidais para o crescimento de frutos do cafeeiro

Coffee is one of the main products of Brazilian agriculture, the country is currently the largest producer and exporter. Knowing the growth pattern of a fruit can assist in the development of culture indicating for example, the times of increased fruit weight and its optimum harvest, essential to improve the management and quality of coffee. Some authors indicate that the growth curve of the coffee fruit has a double sigmoid shape. However, it consists of just a visual observation without exploring the use of regression models. The aims of this study were: i) determine if the growth pattern of the coffee fruit is really double sigmoidal; ii) to propose a new approach in weighted importance re-sampling to estimate the parameters of regression models and select the most suitable double sigmoidal model to describe the growth of coffee fruits; iii) to study the spatial distribution effect of the crop in the growth curve of coffee fruits. In the first article the aim was determine if the growth pattern of the coffee fruit is really double sigmoidal. The models double Gompertz and double Logistic showed significantly superior fit to models of simple sigmoid confirming that the standard of coffee fruits growth is really double sigmoidal. In the second article we propose to consider an approximation of the likelihood as the candidate distribution of the weighted importance resampling, aiming to facilitate the process of obtaining samples of marginal distributions of each parameter. This technique was effective since it provided parameters with practical interpretation and low computational effort, therefore, it can be used to estimate parameters of double sigmoidal growth curves. The nonlinear model double Logistic was the most appropriate to describe the growth curve of coffee fruits. In the third article aimed to verify the influence of different planting alignments and sun exposure faces in the fruits growth curve. A difference between the growth rates in the two stages of fruit development was identified, regardless the side. Although it has been proven differences in productivity and quality of coffee, there was no difference between the growth curves in the different planting alignments herein studied.

Regressão Simplex aplicada a delineamentos de mistura e utilização do Algoritmo Boosting

In the composition of this work are present two parts. The first part contains the theory used. The second part contains the two articles. The first article examines two models of the class of generalized linear models for analyzing a mixture experiment, which studied the effect of different diets consist of fat, carbohydrate, and fiber on tumor expression in mammary glands of female rats, given by the ratio mice that had tumor expression in a particular diet. Mixture experiments are characterized by having the effect of collinearity and smaller sample size. In this sense, assuming normality for the answer to be maximized or minimized may be inadequate. Given this fact, the main characteristics of logistic regression and simplex models are addressed. The models were compared by the criteria of selection of models AIC, BIC and ICOMP, simulated envelope charts for residuals of adjusted models, odds ratios graphics and their respective confidence intervals for each mixture component. It was concluded that first article that the simplex regression model showed better quality of fit and narrowest confidence intervals for odds ratio. The second article presents the model Boosted Simplex Regression, the boosting version of the simplex regression model, as an alternative to increase the precision of confidence intervals for the odds ratio for each mixture component. For this, we used the Monte Carlo method for the construction of confidence intervals. Moreover, it is presented in an innovative way the envelope simulated chart for residuals of the adjusted model via boosting algorithm. It was concluded that the Boosted Simplex Regression model was adjusted successfully and confidence intervals for the odds ratio were accurate and lightly more precise than the its maximum likelihood version.

Análise energética da madeira e do carvão de híbridos entre Corymbia citriodora (Hook.) K.D. Hill & L.A.S. Johnson e Corymbia torelliana (F. Muell.) K.D. Hill & L.A.S. Johnson

This research aimed to evaluate the wood and charcoal quality of hybrids clone of the crossing C. citriodora with C. torelliana in two different locations for charcoal production. Seven with 3,75 years old clones, planted at country of Itamarandiba – MG, and six 6,42 years old clones, planted in Dionísio – MG, were studied. For wood and charcoal quality analysis, samples were collected along the stem of the trees until the commercial height. Properties study of the wood was done by chemical analysis, basic density, superior heat power, and thermogravimetric analysis. The wood samples were carbonized in laboratory conditions with heating rate of 1.67 0 C.min -1 , starting at 100 0 C until 450 0 C and keeping on this temperature for 30 minutes. It were determined the carbonizations gravimetric yield, all in dry basis. The wood quality was evaluated based on the chemical immediate analysis, relative apparent density, and gross heating value. The experiment was installed according to the completely randomized design, with five repetitions. The collected data were submitted to analysis of variance and, when the evaluated effects were significant by “F” test, was applied the Scott-Knott test at 5% probability for multiple comparisons. For correlation analysis, Pearson correlation coefficient, tested by the "t" test at 5% probability was used. Results showed variability of wood between the genetic materials evaluated in relation to place and plant crossing. The thermal analysis of the wood showed significant variation between clones and it was possible to differentiate two stages of degradation (hemicelluloses and cellulose). The majority of the clones presented satisfactory properties for the charcoal production, while, clone 3, planted in Itamarandiba, obtained the best performance due it have the higher yield and energetic efficiency, thus, achieving the best potential for charcoal production. However, clone 9, planted in Dionísio, was the less indicated for charcoal production since it presented the lowest energetic efficiency, gravimetric yield, and densities.

Modelagem do crescimento e produção em povoamentos desbastados de Eucalyptus grandis

The aim of the study was to develop a system of growth and yield models for thinned stands of Eucalyptus spp.; and to assess the behavior of the growth in scenarios with 10% decrease or increase in rainfall. The probability distribution functions Weibull 2 and 3 parameters and Johnson SB for different methods were fitted. Correlation between the fitted parameters with age was evaluated. Dominant height growth behavior was evaluated to check if thinned stand changes its growth when compared to a non-thinned stands. The stand variables dominant height and basal area were projected and simultaneously predicted and projected, respectively. Individual tree equations were fitted, which were fitted as functions of stand level variables in order to decrease the error propagation. R software was used to fit all the proposed models and consequently all the fitted models were evaluated by their parameters significance (F-test) and graphs of predicted values in relation to the observed values around the 1:1 line. Thus, the prognosis system was made by two ways, first one using the full data set, and for the second one the dataset was restricted at age 7.5. Increase and decrease in 20% of rainfall were assessed by updating the site index function. Method of moments was the most precise to describe the diameter distribution for every age in eucalyptus stands for Johnson SB and Weibull 2 parameters pdfs. When observed for each pdf the correlation for their fitted parameters with age, we noticed that shape parameters for a thinned stand were no longer correlated with age, differently of non-thinned stands. Thus, thinning effect was accounted in the basal area prediction and projection modeling. This result emphasized the necessity of applying the Parameter Recovery method in order to assess differences and capture the right pattern for thinned and non-thinned stands in the future. Dominant height was not influenced by thinning intensity. Therefore the fitted Chapman-Richards model did not account for a stand being thinned or not. All the fitted equations behaved with good precision, no matter using full or precocious dataset. The prognosis system using full and/or precocious date set was evaluated for when using Parameter Recovery method for Sb and Weibull pdfs, and by then, graphical analysis and precision statistics showed appropriated results. Finally, the increase or decrease in rainfall regime were observed for eucalyptus stand yields and we may notice how important is to observe this effect, since the growth pattern is strictly affected by water.

A Dimensao Regional do Potencial Exportador Brasileiro: o potencial exportador dos municipios brasileiros com foco na questao regional

A literatura sobre os determinantes do desempenho exportador das firmas industriais é ampla e bem diversificada, tanto na metodologia como nos resultados encontrados Para o caso dos países em desenvolvimento, em particular, a identificação destes determinantes não é tão convergente no sentido de que as relações de causalidade não são claras no que toca à sua direção e à relevância de determinada relação para um país específico. As relações comumente testadas no nível da firma industrial para estes países são as entre exportações e origem do capital (em particular, firmas estrangeiras), inovação e exportações, tamanho, produtividade e exportações, intensidade tecnológica setorial e exportações, eficiência de escala e exportações, indicadores de desempenho, custos fixos, freqüência das exportações e desempenho exportador. Os trabalhos mais recentes no Brasil têm focalizado mais o papel da eficiência de escala como determinante das exportações e o impacto das empresas transnacionais sobre o comércio exterior. Um passo metodológico à frente foi o uso das técnicas de Propensity Score Matching (PSM) para identificar as firmas potencialmente exportadoras, ou seja, firmas não exportadoras que possuem características produtivas e tecnológicas semelhantes a firmas exportadoras, o que contribui para trazer novas luzes à formulação de uma política industrial e tecnológica para o comércio exterior, pois vai além das proposições de reforçar as firmas exportadoras já existentes, ampliando o foco das políticas para exportadores potenciais. O objetivo aqui é trazer uma dimensão espacial do potencial exportador das firmas industriais brasileiras, através da análise das seguintes questões: (1) existe ou não um padrão locacional das firmas industriais que possuem probabilidade de exportar, isto é, das firmas com algum potencial exportador, seja este realizado ou não?; (2) existem determinantes espaciais das firmas com potencial exportador?; (3) existem determinantes espaciais específicos para as firmas com potencial exportador não realizado?