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Contribuições em modelos de regressão com erro de medida multiplicativo
(Universidade Federal de São Carlos, 2016-02-04) Silva, Eveliny Barroso da; Diniz, Carlos Alberto Ribeiro; https://lattes.cnpq.br/3277371897783194; https://lattes.cnpq.br/3911410872456214
In regression models in which a covariate is measured with error, it is common to use structures that correlate the observed covariate with the true non-observed covariate. Such structures are usually additive or multiplicative. In the literature there are several interesting works that deal with regression models having an additive measurement error, many of which are linear models with covariate and measurement error normally distributed. For models having a multiplicative measurement error, one does not find in the literature the same theoretical amount of works as one finds for models in which the measurement error is additive. The same happens in situations where the supositions of normality for the covariates and the measurement errors do not apply. The present work proposes the construction, definition, estimation methods, and diagnostic analysis for the regression models with a multiplicative measurement error in one of the covariates. For these models it is considered that the response variable may belong either to the class of modified power series regression models or to the exponential family. The list of distributions belonging to the family modified power series is rather comprehensive; for this reason this work develops, firstly and in a general way, the models estimation and validation theory, and, as an example, presents the model of negative binomial regression with measurement error. In the case where the response variable belongs to the exponential family, the model of beta regression with multiplicative measurement error is presented. All proposed models were analysed through simulation studies and applied to real data sets.
Biodiversidade de Selenastraceae (Sphaeropleales, Chlorophyceae) : características morfológicas e sequenciamento dos marcadores moleculares 18S rDNA, rbcL e ITS como base taxonômica tradicional
(Universidade Federal de São Carlos, 2016-02-04) Silva, Thaís Garcia da; Vieira, Armando Augusto Henriques; https://lattes.cnpq.br/4428377384377272; https://lattes.cnpq.br/5664802098183026
The phylogeny of the family Selenastraceae was investigated by light microscopy, molecular analysis of 18S rDNA, rbcL, ITS1-5.8S-ITS2 and ITS-2 markers. Several morphological features traditionally used for identification of genera and species were investigated. All Selenastraceae strains studied presented naked pyrenoids within the chloroplast, except for Chlorolobion, which presented starched pyrenoid. Molecular analysis showed that no isolated morphological criteria considered so far is significant for the systematic of Selenastraceae, but a set of characteristics may be appropriate to identify species of genera Ankistrodesmus, Chlorolobion, Kirchneriella, Raphidocelis and Tetranephris. Phylogenetic analyses showed that genera Monoraphidium, Kirchneriella and Selenastrum are polyphyletic and not distinguishable as separate genera. The Selenastrum morphotype revealed three different molecular lineages, leading to the description of two new genera, Curvastrum gen. nov and Messastrum gen. nov. In addition, molecular phylogenetic analysis revealed four lineages assigned to Kirchneriella orphotype, leading to the description of five new species: Genus 1 sp. nov. 1, Genus 2 sp. nov. 1, Genus 2 sp. nov. 2, Raphidocelis sp. nov. and Tetranephris sp. nov.
Estudos de melhorias no processo de hidrólise enzimática de biomassas para produção de etanol
(Universidade Federal de São Carlos, 2016-02-04) Corrêa, Luciano Jacob; Badino Júnior, Alberto Colli; https://lattes.cnpq.br/6244428434217018; Cruz, Antonio José Gonçalves da; https://lattes.cnpq.br/1812806190521028; https://lattes.cnpq.br/6654974812569635
In this work it was evaluated, firstly, the performance of four impellers configurations in the enzymatic hydrolysis of sugarcane bagasse. The configurations evaluated were: (1): Rushton turbine - Rushton turbine; (2): Elephant ear down-pumping and Rushton turbine; (3): Rushton turbine and Elephant ear up-pumping; (4): Elephant ear downpumping and Elephant ear up-pumping. The choice of the best impeller configuration was based in mixing efficiency, characterized by the mixing time. The configurations were also evaluated considering the conversion of cellulose to glucose, power consumption as well as the rheological behavior during hydrolysis. The hydrolysis experiments were carried out in batch stirred tank reactor (3 L) using 10% w/v of solids (pH 4.8; 50°C; 470 rpm), 10 FPU· g-1 biomassa for 96 h. The configuration (4) showed the lowest mixing time and energy efficiency values (ratio of conversion of cellulose to glucose and total energy consumption) of 78.9%·MJ-1. Further, to get a high concentration of glucose associated with low power consumption, it was investigated two operating modes: batch and fed-batch. The strategies evaluated were: E1 [20%]; E2 [10(E)+5+5%]; E3 [5(E)+5+5+5%]; E4 [5(E)+5+5+5%], and E5 5(E)+5(E)+5(E)+5(E)%]. The best energy efficiency was obtained for the E5 strategy in which substrate and enzyme were added simultaneously (0.35 kgglicose·kWh-1). This value was 52% higher than that obtained in the single batch operation (E1). In continuation of the work were carried out enzymatic hydrolysis of exploded and hydrothermal bagasse and cane straw submitted to hydrothermal pretreatment. The experiments were carried out under the conditions: solids loading of 10 (w/v), pH 4.8; 50 ° C; 470 rpm and 10 FPU·g-1 biomass for 96 h. The efficiency obtained in the enzymatic hydrolysis of steam explosion sugarcane bagasse proved to be 41 and 46% higher than the hydrolysis of hydrothermally pretreated sugarcane straw and bagasse, respectively. Finally, a scale-up protocol with a scale factor equal to 1000 was proposed. It was analyzed the maintenance of two parameters on larger scale: the constancy of the mixing time (tm) and the constancy of the power consumption per unit volume (P/V). In turn, maintenance P/V parameter constant, the mixing time and the new scale power consumption (3000L) were approximately 4 and 1000 times higher, respectively, than those values obtained in the smaller scale (3L).