Discussion centered on light-switchable tattoos that use UV to toggle visibility. Several commenters praised the idea - phyzome called it "dope as heck" and suopspaces imagined a real-time calorie tracker on your belly - while Retroid and xgulfie pushed back on practicality and marketing: Retroid warned that regular daylight could make the ink disappear, and xgulfie accused the writeup of overhyping a UV‑reactive mechanism, noting the paper itself says ambient sunlight drives a photostationary state. Teucris urged exploring bistable displays akin to e‑ink instead of skin applications. accountrequired offered a tongue‑in‑cheek Johnny Mnemonic/Blade Runner movie pitch, underscoring the sci‑fi appeal.
Other commenters raised privacy and health angles. Razengan suggested invisible AR markers on clothing as a less invasive route to dynamic fashion, while sleepyguy flagged immune‑system concerns about tattooing and yahthatsart corrected the terminology, saying "auto‑immune" refers to self‑attacking immunity and that tattoos don’t necessarily imply impaired immune function. The discussion split between enthusiasm for playful, novel uses and skepticism about real‑world limitations, safety, and whether calling the chemistry "programmable" is justified.
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Navier-Stokes equations are fundamental in fluid dynamics and describe the motion of viscous fluids. Vi Hart's post explores their mathematical properties and significance in understanding fluid behavior. (patreon.com)
Swordfish washing up on British Columbia's coast indicates changes in ocean conditions and ecosystems. Scientists study these events to understand broader impacts of climate change on marine life. (phys.org)
Delegates will soon vote on whether to eliminate the leap second, which has been added irregularly to keep atomic clocks aligned with Earth's rotation. If approved, a leap hour could be observed in the distant future to replace the leap second. (abc.net.au)
Researchers have used a novel cell reprogramming technique to rejuvenate eye cells in a Phase 1 trial, showing early signs of improved vision in two patients. This approach, approved by the FDA, reverts diseased cells to a healthier state, potentially advancing treatments for eye diseases like glaucoma. (time.com)
Holography was once considered a promising imaging technology, but it has not become widespread or mainstream. Advances have been limited, and the field remains mostly in research and specialized applications. (americanscientist.org)
PubMed.gov has launched Linked Discoveries, an experimental tool that explores connections between research articles and related literature. It creates networks of related studies, highlighting shared conditions, genes, chemicals, and funding sources. (linkeddiscoveries.ncbi.nlm.nih.gov)
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