Two recent studies by psychologists found the joy of giving has more longevity than the joy of getting. The research, soon to be published in the journal Psychological Science, looked at people’s reported happiness after spending money on themselves or giving to other people. In two different scenarios, those who spent the money on themselves reported a steady decline in happiness—an expected condition of diminishing happiness scientists call hedonic adaptation—but those who spent the money on others bucked the phenomenon and maintained a steady level of happiness. —K.C.
If God used the same design for human skin that He did for earthworms, parents would not need to remind their children to stay out of the mud. Earthworms can glide through thick, sticky soil and emerge perfectly clean. Scientists at the Leibniz Institute for New Materials in Germany created a material that mimics the lowly worm’s self-cleaning ability. Their study appears in the journal Advanced Materials.
Earthworms stay clean even when squiggling through moist dirt because they continuously produce a dirt-repelling lubricant on the surface of their skin, which they replenish as needed. Inspired by this feat, the German scientists developed a material made of soft plastic and embedded drops of silicone oil inside it. When the material is pressed, the droplets change shape and move to the surface, where the oil spreads evenly, providing a lubricating layer that reduces friction and repels water and dirt. The lubricated surface also allows the material to glide on solid objects and prevents the growth of microbes. As pressure on the surface is removed, the droplets reform again. The lubricating layer will continue to regenerate whenever pressure increases. “So it reacts dynamically to pressure—like a ‘breathing system,’” Jiaxi Cui, the lead researcher, said in a statement.
The friction-reducing and antimicrobial properties of the new material enable it to sustain more wear, stay clean longer, and reduce the chance of microorganism growth more effectively than other materials. The researchers envision many potential applications in both industry and medicine or anywhere a device needs to glide smoothly through something solid. —Julie Borg