The implementation of alternative harvest systems which are able to accelerate the kinetics of growth of plants, is extremely important to decrease the time of crop. In this sense, Electro-Hydroponic culture, i.e., the application of an electric field in the nutrient solution of the hydroponic culture emerges as an alternative and interesting harvest system. The objective of the present study was to investigate the effect of the electric field applying different intensities of direct current (DC) at the galvanostatic regime (50, 37.5, 25 and 12.5 mA) on the growth of lettuce (Lactuca sativa) plants in hydroponic culture. Fifty lettuce plants were used in a nutrient solution, from which 4 groups composed of ten lettuces each one, were subjected at 12.5, 25, 37.5 and 50 mA, respectively. A fifth group of ten lettuces was used as a reference test, i.e., without application of DC. The experiments were carried out during 16 days. The results reveal that the kinetics of growth of the lettuce is dependent on the applied current; actually it is observed an increase in the foliate area of the plants cultivated in the presence of DC than that obtained in the reference test. Furthermore, the plants subjected at 12.5 mA, revealed an increase in the foliate area of 65.3% and 73.2% in comparison with the reference test.

Abstract:The scientific software installation testing has a main goal: Evaluate if the software meets its requirements and specifications. In this paper, the scientific software installation in six machines is evaluated. The software installation was tested using a PDCA (Plan-Do-Check-Act) approach in 3 machines and were compared with other 3 machines which were installed exclusively based in the installer experience. The software installed on the machines using a PDCA approach for testing, lead to the expected results. Scientific software installation should be tested during the installation and not as a final test. A methodology based on PDCA is recommended for testing scientific software.