Exploring the Bob Ross effect: A psychophysiological investigation.

Watching news broadcasts is known to elicit psychological stress. Conversely, the iconic painter Bob Ross (BR) has risen to pop culture status and amassed a following, as many find the messages and sounds of BR to be soothing and relaxing. Though, it has yet to be directly tested if such exposure can confer psychological or physiological benefit. The purpose of this study was to compare the effects of watching BR versus streaming news on markers of cardiovascular health and profile of mood states (POMS). It was hypothesized that watching BR would increase POMS scores and heart rate variability (HRV). It was also hypothesized that watching the news would increase blood pressure (BP), vascular stiffness (VS), and heart rate (HR). METHODS: In a randomized, controlled, crossover design, 18 young (21 ± 1 yrs, 9 female, 9 male) healthy participants (172.6 ± 9.9 cm, 69 ± 18 kg) were assessed for BP, VS, HR, HRV, and POMS before and after watching an episode of BR or the News matched for time (∼27 mins). RESULTS: A significant interaction effect on POMS scores were observed for, anxiety (p = 0.01), anger (p = 0.008), depression (p = 0.003), fatigue (p = 0.001), and confusion (p = 0.01) domains after watching BR. The LF/HF ratio, an HRV marker of sympathovagal balance, was significantly lower after watching BR (p = 0.04). There were no significant time, condition, or interaction effects on systolic BP, mean arterial pressure, and diastolic BP. CONCLUSION: The "Bob Ross Effect" reduces overall mood disturbance, though appears to exert little influence on the cardiovascular system in this acute paradigm.

Color Transferability from Solution to Solid Using Silica Coated Silver Nanoparticles.

The interpretation of color change in sensors and tests can be linked to incorrect conclusions if the intrinsic color changes are not accounted for. In this work, we study the intrinsic color change associated with the process of embedding nanoparticles in a polymer to create nanocomposite films. We present a safer, faster method to coat silver nanoparticles with silica and employ a seven-factor Plackett-Burman design to identify critical factors in the synthesis. Silver nanodisks with increasing thicknesses of the silica shell showed a decreasing sensitivity of their localized surface plasmon resonance (LSPR) toward changes in the refractive index surrounding the nanoparticle. A color shift of up to 72 nm was observed when bare nanoparticles were embedded in poly(vinyl alcohol), but no color change was perceived when nanoparticles were coated with a 25-nm-thick silica shell. Understanding the origin of color changes intrinsic to the preparation of polymeric nanocomposites aids in the design and correct use of plasmonic sensors.