César Gonçalves de Lima

This study aimed to establish the optimal concentration of purified Kraft lignin (PKL) in the diet of finishing lambs. The experiment was arranged in a randomized block design, with four diets and LKR concentrations of 0, 6, 12, and 18 g/kg DM, with eight Poll Dorset × Texel crossbred lambs per treatment. The experiment was conducted with newly weaned lambs, aged 60 ± 10 days, with an average initial body weight of 23 ± 5 kg. The animals were [...] ABSTRACT This study aimed to establish the optimal concentration of purified Kraft lignin (PKL) in the diet of finishing lambs. The experiment was arranged in a randomized block design, with four diets and LKR concentrations of 0, 6, 12, and 18 g/kg DM, with eight Poll Dorset × Texel crossbred lambs per treatment. The experiment was conducted with newly weaned lambs, aged 60 ± 10 days, with an average initial body weight of 23 ± 5 kg. The animals were

Sabe-se que a ultrassonografia é uma ferramenta diagnóstica acessível e economicamente viável, sendo considerada de eleição para a avaliação hepática. Pretendeu-se com este estudo avaliar qualitativamente (ultrassonografia modo B) e quantitativamente (histogramas em escala de cinza) o fígado de 28 cadelas em diferentes escores de condição corporal (ECC) quanto à presença de infiltração gordurosa; e a veia hepática direita (VHD) (modo B e modo Doppler colorido) quanto à sua visibilidade e presença de fluxo sanguíneo, respectivamente. A hipótese do presente estudo foi que a perda de peso reduziria a gordura hepática e, consequentemente, cessaria seu efeito mecânico sobre o lúmen venoso. Com isso, dividiu-se os cães do estudo em três grupos, de acordo com seu ECC: controle (ECC 4 ou 5), sobrepeso (ECC 6 ou 7) e obeso (ECC 8 ou 9), sendo este submetido à dieta, acompanhamento ultrassonográfico hepático e mensuração seriada de fosfatase alcalina (FA) e alanina aminotransferase (ALT). A dieta foi eficaz para o emagrecimento dos cães, porém a perda de peso não demonstrou efeitos sobre a VHD ou enzimas hepáticas. A utilização de histogramas auxiliou na detecção da gordura hepática e de sua redução ao longo da perda de peso do animal. Sendo assim, esta pode ser considerada uma ferramenta útil e de fácil execução, contribuindo no diagnóstico precoce e monitoramento da esteatose de forma não invasiva.

The objective of this research was to make a diagnosis of the use of cane in animal feed, to know the technological dimension in which is inserted, and to raise opportunities for acting. A questionnaire collected the information on producers. The database was composed of 76 producers and 18 questions, analyzed by the techniques of factor analysis and cluster analysis. In 40% of the properties the work is familiar, in 40% fixed personnel are hired and in 20% other compositions. The area of the properties was less than 20 hectares in 45% of the responses. In 92% of the properties, the main activity is cattle raising, and in 75% of them sugarcane is used for animal feed. Producers with greater specialization in animal husbandry do the best applicability of sugarcane in animal feed. The most varied systems of animal husbandry use sugarcane, whether or there is no technological intensification. The biggest gap observed was the lack of adequate technological diffusion for the potential use of sugarcane for forage purposes by the producers. In this way, one can say that there is much to do for the efforts and resources employed in scientific research to reach the rural producer.

Some experimental studies are carried out considering a longitudinal feature. In view of this, the classical regression models are not able to handle with it, since the independence assumption between the observations is violated. To handle with this kind of data it was proposed the called linear mixed-effects models, where it is possible to model the response variable taking into account the correlation between the observations, and even between the response variables, when there are two or more of them in study, setting a bivariate or multivariate scenario, respectively. For the diagnosis of the linear mixed-effects models the least confounded residuals are quite recommended due to their lower bias in relation to other types of residuals, but it is not so used in the literature. Using a data set of dairy calves’ performance according to three different diets over eight weeks, the linear mixed-effects models theory under univariate and bivariate approach was applied alongside the least confounded residuals in the diagnosis of the model for both approaches. Comparing the univariate and bivariate approaches, the last one was more informative presenting lower standard errors’ values for its estimates, while the least confounded residuals was more efficient than the classical residuals present in the literature. Some experimental studies are carried out considering a longitudinal feature. In view of this, the classical regression models are not able to handle with it, since the independence assumption between the observations is violated. To handle with this kind of data it was proposed the called linear mixed-effects models, where it is possible to model the response variable taking into account the correlation between the observations, and even between the response variables, when there are two or more of them in study, setting a bivariate or multivariate scenario, respectively. For the diagnosis of the linear mixed-effects models the least confounded residuals are quite recommended due to their lower bias in relation to other types of residuals, but it is not so used in the literature. Using a data set of dairy calves’ performance according to three different diets over eight weeks, the linear mixed-effects models theory under univariate and bivariate approach was applied alongside the least confounded residuals in the diagnosis of the model for both approaches. Comparing the univariate and bivariate approaches, the last one was more informative presenting lower standard errors’ values for its estimates, while the least confounded residuals was more efficient than the classical residuals present in the literature.

Analyses of fertilizer are essential to ensuring that fertilizer sold to final users presents chemical and physical qualities in the range determined by law. As regards the sampling of fertilizers, the official method currently used in Brazil for sampling preparation is to reduce the size of the sample (from ~ 3 kg to ~ 0.25 kg) by quartering, followed by grinding (so as to pass through a 0.85 sieve) and nutrient quantification. Herein, we propose an alternative method of sampling preparation by grinding the total sample (~ 3 kg) before quartering to improve accuracy and reduce segregation during quartering. Six formulations of fertilizers (basal samples) were weighed (0.01 kg precision) and sampled according to the two methods (official and alternative), followed by the quantification of nutrient concentration in duplicate. Results showed that both methods presented similar nutrient concentrations for most formulations compared to the basal samples. However, the alternative method presented higher precision (less variation between replicates) and accuracy (versus the basal samples) than the official method. Consequently, the alternative method can be used for sampling preparation fertilizers with high accuracy and precision in determining nutrient concentration.

A inserção de profissionais técnicos no mercado de trabalho desempenha um papel crucial na economia de qualquer país. Esses profissionais são treinados em cursos específicos que lhes proporcionam habilidades práticas e conhecimento especializado em diversas áreas, tais como eletrônica, mecânica, saúde, tecnologia da informação, construção civil, entre outras. A demanda por profissionais técnicos é constante e, eles são altamente valorizados por sua capacidade de resolver problemas práticos e contribuir para a eficiência operacional em uma variedade de setores. A inserção de profissionais técnicos no mercado de trabalho pode ocorrer de várias maneiras. Alguns podem encontrar emprego imediatamente após a conclusão de seus programas de formação técnica, enquanto outros podem passar por estágios ou programas de aprendizado para adquirir experiência prática antes de ingressar no mercado de trabalho em tempo integral. O presente estudo tem como objetivo analisar a inserção de profissionais técnicos no mercado de trabalho. A metodologia utilizada para a elaboração do estudo se trata de uma pesquisa qualitativa, por meio de uma revisão bibliográfica. Conclui-se que a formação técnica desempenha um papel crucial no desenvolvimento econômico e na competitividade de uma nação e, é essencial que haja investimento e valorização contínuos nessa área para atender às demandas do mercado de trabalho em constante evolução.

There are agronomic experiments where measurements of a response variable are carried out over more than one longitudinal factor, for example, at different depths over time. These observations, made systematically in each experimental unit, can be correlated and might have heterogeneous variances at the different levels of the longitudinal factor. It was possible to model this correlation between repeated measures and the heterogeneity of variances by using mixed models. Thus, it was necessary to adapt some covariance structures that are common in experiments with only one longitudinal factor. The objective of this study was to use the class of linear mixed models to study sugarcane root dry mass. The experiment was the randomized complete blocks design and the parcels received four nitrogen doses. Repeated measurements were made over two longitudinal factors, one being qualitative ordinal (depths) and one being quantitative (distances from the planting line). It was possible to select a parsimonious covariance structure and another one to explain the average behavior of the responses through likelihood ratio tests, Wald tests, and using the AIC and BIC information criteria. The adjustment of the selected model was verified by using residual diagnostics graphs.

Yogurt is known as a healthy food, but some synthetic additives that are commonly added to it can be one of the factors that restricts yogurt’s consumption. The aims of this study were to prepare and evaluate yogurts with the addition of spray-dried, anthocyanin-rich colorant extracted from jabuticaba (Myrciaria cauliflora Mart.) skin. The concentrated extract was spray-dried using maltodextrin (20 g/100 g w/w) as a carrier and added to yogurts in the concentrations of 0.5, 1.0, 1.5, and 2.0 g/100 g w/w. The yogurts were stored for up to 28 days under refrigeration and periodically evaluated. Except for the yogurts to which 1.5 g of extract was added, all samples had a slight pH reduction in the first 7 days of storage. Throughout the yogurts’ storage period, the anthocyanin and a* values were slightly reduced (p < 0.05), indicating some anthocyanin instability. The rheological behavior was typical for yogurts, but the casein gel network was probably disrupted by the jabuticaba extract incorporation, reducing the yogurt’s apparent viscosity. Panelists showed good acceptance for the attributes of taste, color, aroma, appearance, texture, and overall impression, indicating that this natural pigment has the potential to be a substitute synthetic color additive for the production of mixed berry yogurts, contributing to the reduction of waste.