• ImplicitCAD’s new CSG engine uses marching-cubes on an implicit signed-distance field (SDF) to generate cleaner meshes and can slice directly from the SDF, eliminating the polygon-mesh step; participants concluded that parametric, version-controlled scripts should remain the canonical design source, while interactive GUI tweaks are only for ideation.

• A debate on 3-D geometry representations highlighted that triangle meshes lose curvature data, subdivision surfaces give intuitive, repair-friendly models for game/print workflows, and implicit/F-rep representations excel at CSG operations.

• fltrz proposed a reagent-less DNA data-storage scheme in which UV-C creates pyrimidine-dimer “zeros” and photolyase + blue light repairs selected dimers to write “ones,” with nanopores providing random-access positioning and read-out.

• A portable UV-C LED (260–275 nm, ozone-free) air-disinfection reactor is being designed for personal use; the design uses a long, baffled aluminum cavity to prevent UV-C exposure and cites a 2020 IUVA fluence-dose PDF for pathogen-inactivation planning.

• Cost-hacking of UV-C LEDs was discussed: 40/50/60 mW parts may be identical dies with different zener diodes for price segmentation, and removing the zener could reclaim efficiency and allow junction-temperature monitoring for lifetime estimation.

• Historical UV-C LED pricing has fallen from >US$100 for 3 mW to ~US$7 for 40 mW through newer suppliers and bulk purchasing.

• Reusable-mask concepts include semi-inflated “bicycle-tire” silicone gaskets for custom face seals and hip-mounted battery-powered blowers feeding the mask, moving beyond single-use surgical masks.

• kanzure shared Dominic Cummings’ 2019 essay on genomics, prediction, and national strategy, plus a paper proposing Bitcoin bounties for demonstrating quantum attacks on cryptographic schemes.

• diyhpluswiki added transcripts from the 2020 Stanford Blockchain Conference covering formal verification, optimistic VMs, coded Merkle trees, and anti-frontrunning mechanisms.