637
top 50 comments
sorted by: hot top controversial new old
[-] jordanlund@lemmy.world 217 points 1 year ago

Also why you don't re-use needles:

[-] LodeMike@lemmy.today 168 points 1 year ago

That's not the main reason why we don't reuse needles.

[-] plantfanatic@sh.itjust.works 37 points 1 year ago

For even into the same patient…

[-] HonoraryMancunian@lemmy.world 20 points 1 year ago

Pfft I reckon we can reuse it once from that pic

[-] captainlezbian@lemmy.world 7 points 1 year ago

Or from draw into injection

[-] princessnorah 5 points 1 year ago

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.

[-] captainlezbian@lemmy.world 7 points 1 year ago

Oh does insulin have a thick rubber stopper? I'm a lemmy stereotype and so my only experience with injections is estrogen

load more comments (1 replies)
load more comments (4 replies)
[-] DaGeek247@fedia.io 130 points 1 year ago

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.

[-] jaybone@lemmy.zip 5 points 1 year ago

Could they be cleaned with isopropyl alcohol or an autoclave?

[-] CXORA@aussie.zone 49 points 1 year ago

It's less about the dirt than the tip deforming.

When the needle is less pointy, it'll hurt more.

[-] MonkeMischief@lemmy.today 21 points 1 year ago

Not only that but look how it forms a freaking fishing hook on the end like a barb. Yikes!!!

[-] reddit_sux@lemmy.world 9 points 1 year ago

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.

[-] Natanox@discuss.tchncs.de 17 points 1 year ago

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.

[-] emergencyfood@sh.itjust.works 8 points 1 year ago

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.

[-] reddit_sux@lemmy.world 11 points 1 year ago

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.

load more comments (1 replies)
[-] NoneOfUrBusiness@fedia.io 27 points 1 year ago

Wow, I did not expect that.

[-] someguy3@lemmy.world 20 points 1 year ago

Can we see the skin after that sixth use?

load more comments (2 replies)
[-] Zacryon@feddit.org 104 points 1 year ago

There was missing something...

[-] vivalapivo@lemmy.today 48 points 1 year ago

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.

[-] MBech@feddit.dk 20 points 1 year ago

Also seems wildly overkill to use an electron microscope for this.

load more comments (1 replies)
[-] flora_explora@beehaw.org 15 points 1 year ago

Yes! When I did electron microscopy, we had to cover the fix the samples and cover them with a very thin gold layer beforehand.

[-] vivalapivo@lemmy.today 12 points 1 year ago

Yeah, and it's impossible to catch color!

[-] alzymologist@sopuli.xyz 37 points 1 year ago

In rationalist hell there is a special teapot for people who color SEM images

[-] Phineaz@feddit.org 34 points 1 year ago

Thanks, I hate it. Not because of the hole, but because of how unhealthy the skin looks in this picture.

[-] cRazi_man@europe.pub 49 points 1 year ago

Were you expecting it to be smooth like plastic? The top layer is basically a bunch of dead skin cells that keep flaking away from the top layer and building up again from the lower layers.

[-] kautau@lemmy.world 8 points 1 year ago

Not if you moisturize

^/s,^ ^of^ ^course,^ ^though^ ^I’m^ ^sure^ ^you^ ^could^ ^put^ ^this^ ^photo^ ^on^ ^Instagram^ ^and^ ^be^ ^like^ ^“this^ ^is^ ^your^ ^skin^ ^without^ ^my^ ^brand^ ^of^ ^healing^ ^lotion^ ^made^ ^of^ ^baby^ ^foreskin”^ ^and^ ^make^ ^plenty^ ^of^ ^sales^

[-] nocturne@slrpnk.net 27 points 1 year ago
[-] tetris11@lemmy.ml 7 points 1 year ago

dehydrate dehydrate dehydrate...

load more comments (3 replies)
[-] sploosh@lemmy.world 11 points 1 year ago

Scanning electron microscopes image in a vacuum. Nothing looks 100% like it does at sea level when you suck all the air out.

load more comments (1 replies)
[-] JayDee@lemmy.sdf.org 21 points 1 year ago* (last edited 1 year ago)

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?

[-] Pulptastic@midwest.social 20 points 1 year ago

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.

load more comments (1 replies)
[-] ikidd@lemmy.world 19 points 1 year ago

Put a needle in someone, freeze them solid with liquid nitrogen, then take a picture. Throw body out with rest of specimens.

Easy peasy.

[-] Duckingold@lemmy.world 14 points 1 year ago

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.

[-] princessnorah 5 points 1 year ago

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.

load more comments (2 replies)
[-] lena@gregtech.eu 20 points 1 year ago

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

[-] far_university1990@reddthat.com 9 points 1 year ago

Yes ( ͡° ͜ʖ ͡°)

[-] kuhli@lemmy.dbzer0.com 18 points 1 year ago
[-] hazl 12 points 1 year ago

The pores on my face as seen by the naked eye.

[-] Siegfried@lemmy.world 9 points 1 year ago

Everything reminds me of her

[-] Allero@lemmy.today 7 points 1 year ago

Just about everything can seem big when you have an electron microscope

[-] socsa@piefed.social 7 points 1 year ago

I should also call your mom.

[-] vaultdweller013@sh.itjust.works 6 points 1 year ago

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.

[-] LordWiggle@lemmy.world 5 points 1 year ago

It also happens to be just big enough for Trump his penis.

[-] FerretyFever0@fedia.io 5 points 1 year ago

Skin kinda looks like dried up paint (I don't paint). Is this dryer than normal, or?

[-] DaGeek247@fedia.io 4 points 1 year ago

Apparently electron microscopes work in a vacuum. So this is a needle hole in skin, in a vacuum.

load more comments
view more: next ›
this post was submitted on 09 Aug 2025
637 points (100.0% liked)

Science Memes

21018 readers
1379 users here now

Welcome to c/science_memes @ Mander.xyz!

A place for majestic STEMLORD peacocking, as well as memes about the realities of working in a lab.



Rules

  1. Don't throw mud. Behave like an intellectual and remember the human.
  2. Keep it rooted (on topic).
  3. No spam.
  4. Infographics welcome, get schooled.


Research Committee

Other Mander Communities

Science and Research

Biology and Life Sciences

Physical Sciences

Humanities and Social Sciences

Practical and Applied Sciences

Memes

Miscellaneous

founded 3 years ago
MODERATORS