I should also call your mom.

This is my hole. It was made for me.
DRR… DRR… DRR…
no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no
Yes ( ͡° ͜ʖ ͡°)
In rationalist hell there is a special teapot for people who color SEM images
It also happens to be just big enough for Trump his penis.
Also why you don’t re-use needles:

That’s not the main reason why we don’t reuse needles.
One of the many
For even into the same patient…
Pfft I reckon we can reuse it once from that pic
Or from draw into injection
Insulin needles are used in this way, because they’re usually permanently attached to their syringe. Rather than using a drawing needle then an injection needle.
Oh does insulin have a thick rubber stopper? I’m a lemmy stereotype and so my only experience with injections is estrogen
Uhm… same! So I couldn’t tell you. I do have a friend that’s type 1, but she uses an insulin pump these days.
I’m a lemmy stereotype and so my only experience with injections is estrogen
This is peak Lemmy right there lmao
Aye, and besides drug users on the streets, that’s who the top picture was actually for. I can’t recall how many of those signs I’ve seen when I was picking up needles with my insulin. I also know my uncle reused his up to 10 times or so. Worst I’ve ever gone was like 5-6. It’s actually quite difficult to get needles when you’re not at home and forget some (and they’re annoyingly easy to forget).
Wait, what? I meant reused as in the vial and my body…
Yes, I get that. So what I was saying, in a continuation of your comment on insulin needles being used that way, was that the top picture here, showing what needles looked like after multiple times of use, was most often displayed near pharmacies, where insulin and needles were dispensed to diabetics. I saw them there more than I ever saw them in anti-drug areas/campaigns. I was further adding in the perspective that there was a good reason for doing that, as diabetics (and probably other users of injected drugs) were most definitely reusing needles, as evidenced by the stories from my uncle and my own experience.
It’s a little misleading in that the last photo is zoomed in a lot more than the previous ones. This one has that without the extra zoom in.

Could they be cleaned with isopropyl alcohol or an autoclave?
Autoclave will deform the needle even more. The edge of the tip is made from softer steel so that it is sharper while at the same time more deformable.
Needles were autoclaved and re-used once upon a time, so it should be possible. But disposable needles are probably made of softer material than reusable ones.
Those were made up harder steel which can’t be sharpened to the degree softer steel can be. Harder steel shatters if sharpened since harder it is brittle it becomes.
So reusable needle are blunt, so injections are painful. And as mentioned by @Natanox@discuss.tchncs.de they used to shatter inside the body after a few cycles of autoclaving.
Assumably also for manufacturing and safety reasons. You don’t want the tip of a needle to shatter inside you, softer steel won’t do that. And it’s a little bit easier to manufacture with softer steel as well.
It’s less about the dirt than the tip deforming.
When the needle is less pointy, it’ll hurt more.
Not only that but look how it forms a freaking fishing hook on the end like a barb. Yikes!!!
Comparing the pictures it looks like the exact same set of photos except like you said, more zoomed in.
Can we see the skin after that sixth use?

To shreds, you say.
Wow, I did not expect that.
So when nurse misses a vein and want to try again you should ask them to uae a new needle?
For good procedure, yes.
…hmmmmmm…
Skin kinda looks like dried up paint (I don’t paint). Is this dryer than normal, or?
Apparently electron microscopes work in a vacuum. So this is a needle hole in skin, in a vacuum.
the ‘paint flakes’ are what fall off and become what dust is, so yeah I think it’s kind of normal

Hard to believe. To prepare a sample for an electron microscope you need to freeze it to nitrogen temperatures or below. You can fix it using glutaraldehyde, but again, you need to cut it accurately immediately after the penetration. My bet is that either stabbed dead skin or some sort of graphics.
Also seems wildly overkill to use an electron microscope for this.
That’s an elephant in the room here
Yes! When I did electron microscopy, we had to cover the fix the samples and cover them with a very thin gold layer beforehand.
Yeah, and it’s impossible to catch color!
Any hole’s a goal
Most SEMs use a vacuum chamber to get their photos. Also, it’s not uncommon to sputter a conductive coating onto the surface you’re scanning.
How the hell did they get this photo?
Probably just a chunk of skin, not a whole person
It likely wasn’t done on an electron microscope, or at least there is no reason to. There is no scale bar, but quick look online tells me a very fine needle is about 0.016in. 500x magnification optical lens would give you more than enough resolution for a photo like that.
I’m more intrigued by the fact there’s no blood, they must’ve taken this milliseconds after the needle was removed? Or it’s a dead body.
Environmental SEMs do not require vacuum and can be used for nonconductive samples. The beam ionizes the air which prevents the sample from charging. Magnification is limited but it is more than enough for this.
You can tell it is SEM and not optical by the depth of field. An optical image at this magnification would have much less DoF so the peaks/valleys would be blurry.
That’s very cool. I had not heard of ESEMs till you commented. I’ll have to look into them more.
Put a needle in someone, freeze them solid with liquid nitrogen, then take a picture. Throw body out with rest of specimens.
Easy peasy.
They could have remained a portion of the skin.
But as another commenter notes, this is too large to need an electron microscope.Edit: then another comment says otherwise, and cites the collection it is from.
The pores on my face as seen by the naked eye.
That old familiar sting.
Wonder what it looks like after I scratch it for 50 minutes straight because my pain receptors are bad and I won’t stop till I see blood.




















