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.

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Desempenho operacional de smartphones em levantamentos planimétricos GNSS sobre coberturas vegetais de pastagem e Pinus elliottii EngelmOperational performance of smartphones in GNSS planimetric surveys on pasture coverages and Pinus Elliottii Engelm

O trator agrícola desempenha importante função no setor rural. Em concomitante, vem a segurança do operador na operação e no deslocamento dos tratores em vias de circulação. Assim, o objetivo deste trabalho foi examinar as produções científicas sobre acidentes com tratores em vias públicas brasileiras. Para isso, foi realizada uma revisão de literatura do período de 2012 a 2016, em recursos disponíveis on-line, sendo selecionadas 36 produções científicas. Por meio da análise, foi observado que mais de 50% do total dos acidentes com máquinas agrícolas ocorrem em vias públicas de circulação, com destaque para a colisão, observada em 77% das ocorrências. Quanto às regiões do país, Sul, Sudeste e Centro-Oeste apresentaram o maior número de acidentes. De modo geral, as publicações sobre acidentes em vias públicas no Brasil, voltadas para as máquinas e tratores agrícolas, mostraram-se incipientes e demonstram possibilidade de abrangência em rodovias estaduais e municipais. Ainda são necessárias políticas públicas voltadas para o problema, criando condições e mecanismos capazes de maximizar ações, visto que a falta de conhecimento e de informação sobre a operação segura do maquinário e sua relação com os acidentes é comum entre os operadores.

The aim of this work was to evaluate the effect of different concentrations of aluminum (Al) on physiological and biochemical parameters of Luehea divaricata seedlings grown in a hydroponic system under greenhouse conditions to verify the possible tolerance to Al or phytoremediation potential of this species. Seeds of Luehea divaricata were placed to germinate in commercial substrate and after 30 days the seedlings were transferred to a hydroponic system with a complete nutrient solution, pH at 4.5±0.1, with daily adjustment. After 20 days of acclimatization, homogenous plants were selected and transferred to a new nutrient solution (without phosphorus (P) and pH at 4.5±0.1) with different concentrations of Al: 0, 25, 50, 75 and 100 mg L -1 , each treatment being composed of 10 replicates of one plant each. The experiment was conducted in a completely randomized design. After seven days of exposure to the treatments, plants were collected for physiological and biochemical analyzes. Aluminum promoted a significant reduction in fresh and dry weight of roots, stems and leaves; in plant height; leaf number; leaf area; and pigment content. On the other hand, Al promoted an increase in lipid peroxidation and guaiacol peroxidase enzyme activity. Therefore, the presence of Al in the growth medium, for the studied conditions, altered significantly both physiological and biochemical parameters in Luehea divaricata seedlings, presenting a sensitive behavior to this element. Due to these characteristics, the studied species does not show phytoremediation potential.