
Color-changing ink turns clothes into giant chemical sensors - prostoalex
https://www.scientificamerican.com/article/color-changing-ink-turns-clothes-into-giant-chemical-sensors/
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VLM
If you want to see state of the art 40 years ago there's Army M9 detector
paper which is this concept applied to tape instead of fabric, and detecting
multiple chemical agents instead of lactate.

Using pH to determine intensity is ingenious.

My experience in the Army was

1) Supply is enough of a hassle under normal circumstances such that having to
replace after it detects is a pain.

2) It was always unclear if a faint color change meant a minor exposure or
some kind of contaminant laundry malfunction type thing.

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kingkawn
In the early 90s hypercolor shirts would change color depending on the
temperature.

[https://en.m.wikipedia.org/wiki/Hypercolor](https://en.m.wikipedia.org/wiki/Hypercolor)

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jwilk
Non-mobile link:
[https://en.wikipedia.org/wiki/Hypercolor](https://en.wikipedia.org/wiki/Hypercolor)

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rapnie
And with the slightest, tiniest scroll movement accidentally made with my
thumb on my mobile, the cookie popup disappeared. Since I'm scrolling that
must mean I consent to being tracked, right?

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dsukhin
Not to disagree with your premise, but if you scrolled back to the top, the
cookie consent box reappears. It just hides so you can read the article when
you scroll which by itself isn't bad. It's not clear it assumes consent but
it's also not clear it doesn't.

IMHO the cookie consent box is a flawed premise from the start, it's annoying
to the user (especially on mobile where it takes half the screen) and there is
no way to verify it is actually implemented correctly and doesn't just track
you anyway regardless of what you do - hence your comment above.

If one really decides a first party cookie is a privilege rather than a simple
data storage primitive on the web because it's been abused by google analytics
etc, this is something you can set your browser to ask for permission each
time or a content blocker to avoid from sources like Google. Keep in mind,
that does affect the site's ability to understand which of it's content is
most popular which is not bad on its own - but yes there are workarounds to
this too like server logs which are probably more reliable anyway.

This cookie box is the most annoying side effect of GDPR with almost no
benefit as it's riddled with dark patterns and "compliant" sites that don't
respect the spirit of the law, just the letter.

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b0rsuk
My mom told me a few times that, as a little girl, she wished she could see
peoples' farts. Their color would depend on what they ate. I hope they hurry
so my mother's childhood dream comes true.

