Sleep reduction impairs the performance of many tasks, so it may affect a basic cognitive process, such as working memory, crucial for the execution of a broad range of activities. Working memory has two storage components: a phonological and a visuospatial component. The objective of this study was to analyze the effects of sleep reduction for 5 days on the storage components of working memory. Thirteen undergraduate students (18.77±2.20 years of age), 5 men and 8 women, responded two N-Back tasks (auditory and visual), with three sections each (0-Back, 1-Back, and 2-Back). These tasks were performed at 13:00 h under the following conditions: before sleep reduction (control; C); on the first (SR1), fourth (SR4), and fifth (SR5) days of sleep reduction (4 h of sleep per night); and one day after they slept freely (recovery, R). Sleep reduction produced a decrement in accuracy on the auditory 2-Back section the fifth day of sleep reduction (C=87.86±13.35%; SR5=74.76±16.37%; F=14.57, p<0.01). In the visual 2-Back section accuracy decreased (C=88.10±9.95%; SR1=82.45±11.57%; SR5=77.76±14.14%; F=10.80, p<0.05), and reaction time increased (C=810.02±173.96 ms; SR1=913.51±172.25 ms; SR5=874.78±172.27 ms; F=10.80, p<0.05) on the first and fifth day of sleep reduction. In conclusion, five days of sleep reduction produces a decrease in the phonological and visuospatial storage components of working memory, which may interfere with processing verbal information and solving problems that require spatial analysis.

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6201 aluminum alloy is mostly used in electrical conductors for overhead transmission lines due to its excellent mechanical and electrical properties besides to an excellent corrosion resistance. This alloy is heat treatable and the thermal treatment is performed with the objective of obtain the optimal properties for its application. In this work it was studied the effect of different deformation grades, time variation of natural aging as well as the time and temperature of artificial aging on the evolution of mechanical and electrical properties. It was found that solution treated wires at 560°C by 4h, 14 days natural aged, 92% cold deformed and artificial aged at 165°C by 7h, reach a tensile stress of 326 MPa and an electrical conductivity of 57.2%IACS (International Annealed Copper Standard).

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The degree of hydrolysis (DH) of the ingredients was evaluated for