Mathematical modeling and multivariate analysis applied earliest soybean harvest associated drying and storage conditions and influences on physicochemical grain quality.

Anticipating the harvest period of soybean crops can impact on the post-harvest processes. This study aimed to evaluate early soybean harvest associated drying and storage conditions on the physicochemical soybean quality using of mathematical modeling and multivariate analysis. The soybeans were harvested with a moisture content of 18 and 23% (d.b.) and subjected to drying in a continuous dryer at 80, 100, and 120 °C. The drying kinetics and volumetric shrinkage modeling were evaluated. Posteriorly, the soybean was stored at different packages and temperatures for 8 months to evaluate the physicochemical properties. After standardizing the variables, the data were submitted to cluster analysis. For this, we use Euclidean distance and Ward's hierarchical method. Then defining the groups, we constructed a graph containing the dispersion of the values of the variables and their respective Pearson correlations for each group. The mathematical models proved suitable to describe the drying kinetics. Besides, the effective diffusivity obtained was 4.9 × 10-10 m2 s-1 promoting a volumetric shrinkage of the grains and influencing the reduction of physicochemical quality. It was observed that soybean harvested at 23% moisture, dried at 80 °C, and stored at a temperature below 23 °C maintained its oil content (25.89%), crude protein (35.69%), and lipid acidity (5.54 mL). In addition, it is to note that these correlations' magnitude was substantially more remarkable for the treatments allocated to the G2 group. Furthermore, the electrical conductivity was negatively correlated with all the physicochemical variables evaluated. Besides this, the correlation between crude protein and oil yield was positive and of high magnitude, regardless of the group formed. In conclusion, the early harvest of soybeans reduced losses in the field and increased the grain flow on the storage units. The low-temperature drying and the use of packaging technology close to environmental temperatures conserved the grain quality.

Agricultural tractors conformity to the Brazilian traffic lighting and signaling legislation / Conformidade de tratores agrícolas à legislação brasileira de iluminação e sinalização para tráfego

ABSTRACT: Increasing the agricultural machinery visibility makes public roadways traffic safer by reducing the number of accidents and their severity. The study aimed to verify the compliance of new agricultural tractors with Brazilian law, given by, CONTRAN Resolution N° 454, NR12 and NR31, regarding the presence of lighting and signaling elements for traffic. The study was carried out in agricultural machinery dealers of seven brands, corresponding to 50 different models of new wheeled agricultural tractors. The items that was not present in total tractors sample are the rear position lamp, the reverse light and the rear retro-reflector. In addition, only one of the seven brands studied showed complete compliance with evaluated elements. Although, the Brazilian legislation specify the presence of lighting and signaling items for agricultural tractors traffic, there is not fully comply on tractors models analyzed and the Brazilian law are not homogeneously met by the agricultural tractor manufacturers in the verified sample, what can be leading to tractors traffic accident occurrences.

RESUMO: Aumentar a visibilidade das máquinas agrícolas torna o tráfego em vias públicas mais seguro, reduzindo o número de acidentes e sua gravidade. O estudo teve como objetivo verificar a conformidade dos tratores agrícolas com a legislação brasileira, dada pela Resolução CONTRAN N°454, NR12 e NR31, quanto a presençados elementos de iluminação e sinalização para o tráfego. O estudo foi desenvolvido em concessionárias de máquinas agrícolas de sete marcas, correspondendo a 50 modelos distintos de tratores agrícolas de pneus, novos. Os itens que não estavam presentes na totalidade de tratores avaliados foram a luz de posição traseira, a luz de marcha à ré e as faixas retrorrefletivas. Apenas uma das sete marcas estudas apresentou total conformidade dos itens avaliados. Apesar da legislação brasileira especificar a presença dos elementos de iluminação e sinalização para o tráfego de tratores em vias públicas, não há total conformidade nos modelos avaliados e a legislação não é cumprida de forma homogênea pelos fabricantes, o que pode estar relacionado à ocorrência de acidentes com tratores agrícolas no tráfego.