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Incidentally, anyone know what is going on with this image - “Cryo-EM map of a center slice of the ushikuvirus particle”: https://journals.asm.org/cms/10.1128/j

Incidentally, anyone know what is going on with this image - “Cryo-EM map of a center slice of the ushikuvirus particle”: https://journals.asm.org/cms/10.1128/jvi.01206-25/asset/1357dcfc-5856-4bd3-a7f6-f96db6c2bcd4/assets/images/large/jvi.01206-25.f011.jpg https://journals.asm.org/cms/10.1128/jvi.01206-25/asset/1357... It’s one quarter of an image flipped horizontally and then vertically, you can see the patterns. It’s a bit odd to do that? Shouldn’t it just be the original EM image?

jiggawatts 9mo ago
Rampant fraud in science papers has reached the point where hobbyists can point out obviously fake charts and graphics even in prestigious journals. Publish or perish needs to end.
- jibal 9mo ago
  This isn't fraud ... see the informative comments nearby.
RicoElectrico 9mo ago
According to this article the image is computed and not really directly captured https://www.chemistryworld.com/news/explainer-what-is-cryo-electron-microscopy/3008091.article https://www.chemistryworld.com/news/explainer-what-is-cryo-e...
observationist 9mo ago
https://www.sciencedirect.com/science/article/pii/S104784772100085X https://www.sciencedirect.com/science/article/pii/S104784772... - there are similar results in this paper, too. After a bit of digging - it looks like it's done to sharpen features as one of the standard steps in producing these images. Where there are rotational symmetries in the things they're looking at, they focus on the smallest unit, and then rotate accordingly. If you had a trilateral symmetry, or hexagonal structure, they'd rotate 3 or 6 times around the center. You're not getting a real image of the thing, but apparently it's got data from those other segments mixed in with the rotations, so you're getting a kind of idealized structure, to make the details being studied pop out, but if you have some sort of significant deviation, damage, or non symmetric feature it'll show up as well. It's called "imposed symmetry" https://discuss.cryosparc.com/t/what-is-actually-occuring-when-symmetry-is-imposed/11733 https://discuss.cryosparc.com/t/what-is-actually-occuring-wh... Neat stuff, cool thing to catch!
- Terr_ 9mo ago
  So kind of like taking a picture of a human, and then taking each half, flipping along the midline, and blending to get an idealized Symmetrical Human?
  - deleted 9mo ago
    [deleted]
  - hnlmorg 9mo ago
    Humans aren’t symmetrical though. This would more like zooming into one edge of a snowflake and then rotating it.
    - Terr_ 9mo ago
      > Humans aren’t symmetrical though. Perhaps you assumed a "radially" which wasn't part of my analogy? :p Land animals have a pretty consistent trend of exterior bilateral symmetry which is very noticeable. (Naturally, a completely normal Hunam such as myself cannot speak for how it may work in places other than my home planet Dirt.)
      - hnlmorg 9mo ago
        I understood you meant bilateral symmetry. And yes, there are similarities, but we are not bilaterally symmetric. At least not to the extent where you can flip an image and have that look normal. Even faces look weird when flipped that way (there have been studies on this effect too). And that’s before you get into the issue that it’s common to have differently shaped breasts, different sized hands or feet. Ears shaped differently. Non-uniform teeth. And so on and so forth.
      - yencabulator 9mo ago
        Only superficially. https://en.wikipedia.org/wiki/Axial_twist_theory https://en.wikipedia.org/wiki/Axial_twist_theory
Bjartr 9mo ago
I think that might just be the original and it simply is symmetrical to that degree. I found a few more examples of "cryo-em center slices" and I've yet to find one that doesn't have really strong symmetry down to the small dot patterns. A different paper, this figure shows a number of cryo-em images, including a simulation, and they all show the same degree of pattern symmetry https://www.researchgate.net/figure/Central-sections-through-cryo-EM-density-maps-of-Fab-labeled-and-control-HBV-capsids_fig2_10583392 https://www.researchgate.net/figure/Central-sections-through... First figure in this third paper also shows symmetry of small patterns https://journals.asm.org/doi/10.1128/jvi.00990-22 https://journals.asm.org/doi/10.1128/jvi.00990-22
- Chance-Device 9mo ago
  Thanks, those examples make it pretty clear. I still think it’s super weird that it looks exactly like an EM image, but is generated. Anyway, good to know!

jiggawatts 9mo ago

Rampant fraud in science papers has reached the point where hobbyists can point out obviously fake charts and graphics even in prestigious journals. Publish or perish needs to end.

jibal 9mo ago
This isn't fraud ... see the informative comments nearby.

RicoElectrico 9mo ago

According to this article the image is computed and not really directly captured https://www.chemistryworld.com/news/explainer-what-is-cryo-electron-microscopy/3008091.article https://www.chemistryworld.com/news/explainer-what-is-cryo-e...

observationist 9mo ago

https://www.sciencedirect.com/science/article/pii/S104784772100085X https://www.sciencedirect.com/science/article/pii/S104784772... - there are similar results in this paper, too. After a bit of digging - it looks like it's done to sharpen features as one of the standard steps in producing these images. Where there are rotational symmetries in the things they're looking at, they focus on the smallest unit, and then rotate accordingly. If you had a trilateral symmetry, or hexagonal structure, they'd rotate 3 or 6 times around the center. You're not getting a real image of the thing, but apparently it's got data from those other segments mixed in with the rotations, so you're getting a kind of idealized structure, to make the details being studied pop out, but if you have some sort of significant deviation, damage, or non symmetric feature it'll show up as well. It's called "imposed symmetry" https://discuss.cryosparc.com/t/what-is-actually-occuring-when-symmetry-is-imposed/11733 https://discuss.cryosparc.com/t/what-is-actually-occuring-wh... Neat stuff, cool thing to catch!

Terr_ 9mo ago
So kind of like taking a picture of a human, and then taking each half, flipping along the midline, and blending to get an idealized Symmetrical Human?
- deleted 9mo ago
  [deleted]
- hnlmorg 9mo ago
  Humans aren’t symmetrical though. This would more like zooming into one edge of a snowflake and then rotating it.
  - Terr_ 9mo ago
    > Humans aren’t symmetrical though. Perhaps you assumed a "radially" which wasn't part of my analogy? :p Land animals have a pretty consistent trend of exterior bilateral symmetry which is very noticeable. (Naturally, a completely normal Hunam such as myself cannot speak for how it may work in places other than my home planet Dirt.)
    - hnlmorg 9mo ago
      I understood you meant bilateral symmetry. And yes, there are similarities, but we are not bilaterally symmetric. At least not to the extent where you can flip an image and have that look normal. Even faces look weird when flipped that way (there have been studies on this effect too). And that’s before you get into the issue that it’s common to have differently shaped breasts, different sized hands or feet. Ears shaped differently. Non-uniform teeth. And so on and so forth.
    - yencabulator 9mo ago
      Only superficially. https://en.wikipedia.org/wiki/Axial_twist_theory https://en.wikipedia.org/wiki/Axial_twist_theory

Bjartr 9mo ago

I think that might just be the original and it simply is symmetrical to that degree. I found a few more examples of "cryo-em center slices" and I've yet to find one that doesn't have really strong symmetry down to the small dot patterns. A different paper, this figure shows a number of cryo-em images, including a simulation, and they all show the same degree of pattern symmetry https://www.researchgate.net/figure/Central-sections-through-cryo-EM-density-maps-of-Fab-labeled-and-control-HBV-capsids_fig2_10583392 https://www.researchgate.net/figure/Central-sections-through... First figure in this third paper also shows symmetry of small patterns https://journals.asm.org/doi/10.1128/jvi.00990-22 https://journals.asm.org/doi/10.1128/jvi.00990-22

Chance-Device 9mo ago
Thanks, those examples make it pretty clear. I still think it’s super weird that it looks exactly like an EM image, but is generated. Anyway, good to know!