Re: Physicists discover a new switch for superconducti...

Apparently one of the things that happens when a material transitions into a superconducting state is it stretches (by an infinitesimal amount) in the conducting direction. This stretching is not like usual stretching where there’s a change in the actual structure of the material. Rather, it is the bonds between each atom that stretch - pulling them into a slightly different state, one that happens to let electrons flow completely freely (ie superconducting). This “infinitesimal stretching” is usually caused by magnetic alignment, which is induced by super cold temperatures.

But there are a few odd materials, like iron selenide, that don’t seem to show any kind of magnetic alignment despite being able to become superconducting. That’s where the absolute geniuses behind this paper come in. They took a thread of iron selenide and stuck it to a strip of titanium, then physically stretched the titanium. This induced that “infinitesimal stretching” in the iron selenide sample. By examining the sample with X-rays while artificially inducing the stretch, they could detect the mechanism that would usually be the cause of the stretch. Essentially it is sort of like manually spinning the wheels on a car and watching the engine cycle, in order to understand how vehicles work.

Very clever stuff, and it seems like a real advance in understanding superconductivity. The article doesn’t really go into it, but this does suggest there might be a third axis (“super precise tension”), alongside the usual two of “super low temperature” and “super high pressure”, that we can search along to find new superconductors.

fwlr, 1 day ago

Ну прям уж «любое» декантировать не стала бы, но вот после бочки - вполне. Аналогия про форточку - шикарна

Дружинники на проспекте Славы, начало 1980-х.

Re: macOS command-line tools you might not know about

You can use sips together with iconutil to generate a complete .icns file for your app from a single 1024 by 1024 PNG without any third party software:



mkdir MyIcon.iconset
cp Icon1024.png MyIcon.iconset/icon_512x512@2x.png
sips -z 16 16 Icon1024.png --out MyIcon.iconset/icon_16x16.png
sips -z 32 32 Icon1024.png --out MyIcon.iconset/icon_16x16@2x.png
sips -z 32 32 Icon1024.png --out MyIcon.iconset/icon_32x32.png
sips -z 64 64 Icon1024.png --out MyIcon.iconset/icon_32x32@2x.png
sips -z 128 128 Icon1024.png --out MyIcon.iconset/icon_128x128.png
sips -z 256 256 Icon1024.png --out MyIcon.iconset/icon_128x128@2x.png
sips -z 256 256 Icon1024.png --out MyIcon.iconset/icon_256x256.png
sips -z 512 512 Icon1024.png --out MyIcon.iconset/icon_256x256@2x.png
sips -z 512 512 Icon1024.png --out MyIcon.iconset/icon_512x512.png
iconutil -c icns MyIcon.iconset


As a bonus, generate .ico with ffmpeg:

ffmpeg -i MyIcon.iconset/icon_256x256.png icon.ico


Incidentally, does anyone know enough about the way sips scales PNGs to confirm that it makes sense to create the 16px version straight from 1024px, as opposed to basing it off 32px (and all the way up)? I.e., is it better to downscale in fewer steps (as currently) or in smaller steps?

strogonoff, 15 hours ago

Re: The hidden cost of air quality monitoring

Achim from AirGradient here. Nice to see my blog post getting some attention.

I think the underlying picture here really is that I and my co-founder are both heavily affected by air pollution in Northern Thailand and are seeing how it affects the health of thousands of people.

We believe strongly that air quality monitoring should be affordable so that people from poorer regions and countries can afford air quality monitoring and thus protect their health by knowing when the air quality turns bad. This is one of the reasons why we open-sourced our air quality designs [1] and are working with many NGOs and Universities to bring accurate low-cost air quality monitoring to underserved communities around the world.

Since we are a self-funded company we do not have pressure to maximize profit but can work under the mantra "Impact first (and profit will follow if we do a good job)."

By the way, if you work in air quality research, we are currently running a global co-location test program and are interested in additional partners [2].

[1] https://www.airgradient.com/kits/

[2] https://www.airgradient.com/research/

ahaucnx, 7 hours ago

Re: Canada plans brain drain of H-1B visa holders, wit...

We should shift our perspective on our native-born citizens. Because they're such a massive economic drain we should _stop_ investing in them completely. I know it sounds radical but hear me out. We can realize higher economic utility for our society if A) we stop all investments in non-skilled, non-working-age citizens and B) export those people who are a burden on our society (children, the elderly, the sick, people who enjoy EDM, you get it).

In this way Canada can achieve higher economic utility for itself. I'm imagining a system where everyone in the society is brought in on a temporary basis. They are imported after their post-secondary education and exported maybe 10 years before their retirement. In this way we avoid all the costs associated with having "people" in our country and instead we reap the economic reward of their labor!

I guess I shouldn't say "our" country. I would be exported fairly quickly... But! To those glorious (and brave) few on the executive committee entrusted to leading Canada Inc. through these difficult times, the society they get to inhabit will undoubtedly be the economic envy of the world!

stickyricky, 6 hours ago