Video camera with 4.4 trillion FPS

[TonyStewart14]

http://www.iflscience.com/technology/wo ... mes-second

I wonder if we could soon have a recording of an actual protein folding?

[billford]

http://www.iflscience.com/technology/wo ... mes-second

I wonder if we could soon have a recording of an actual protein folding?

I posted that link in another forum I use, and someone commented:

And you still wouldn't be able to capture the moment that a political party u-turns on policy...

But being serious- as I understand it, it uses light in the (more or less) visible range, which has far too long a wavelength to be of any use for watching atoms move.

You'd need to go to X-rays or beyond, and promptly run into the brick wall of the observer effect, and anyway it's too slow by a couple of orders of magnitude (using the FAH step size of 2 femto-seconds as a guide)

[popandbob]

According to wikipedia....
1.3 fs – cycle time for 390 nanometer light, at the transition between violet visible light and ultraviolet[5]
2.57 fs – cycle time for 770 nanometer light, at the transition between red visible light and near-infrared[5]

and this camera does a frame every 2.2^-13 seconds (a fs is 10^-15 seconds)
so quite close but no cigar...

http://en.wikipedia.org/wiki/Femtosecond

Bob

[billford]

According to wikipedia....
1.3 fs – cycle time for 390 nanometer light, at the transition between violet visible light and ultraviolet[5]
2.57 fs – cycle time for 770 nanometer light, at the transition between red visible light and near-infrared[5]

The cycle time (reciprocal of frequency) isn't the problem- also from Wiki, bond lengths and atomic diameters are in the range 100-200 picometers so the spatial resolution is insufficient by a factor of at least 3,000, even for light at the blue end of the spectrum.

Someone from PG might be better qualified to comment than I am (it's not my area of expertise) but I doubt that, using visible light, it would be possible to resolve even a single giant protein molecule, let alone the small ones that FAH can handle. Those wishing to study molecular structure use X-ray crystallography for good reasons, and that's a technique about as unsuited to producing real-time movies as you can get

and this camera does a frame every 2.2^-13 seconds (a fs is 10^-15 seconds)
so quite close but no cigar...

http://en.wikipedia.org/wiki/Femtosecond

Yup, a factor of 110 more than FAH's step time. Opinions vary of course, but I don't call that "quite close"

I always hesitate to say that anything technological is truly impossible, but a movie of a protein folding seems pretty unlikely. That having been said, I've often wondered if PG have ever used their data to produce a "movie" of a trajectory from start to finish, it could be a useful "advert" for the FAH project.

[bruce]

"Start to finish" data has not yet been completed, even for relatively small proteins.

THe most popular video shows one full millisecond of folding of NTL9.
https://www.youtube.com/watch?v=gFcp2Xpd29I
The video was(produced a few years ago so you may have seen it. Work is still continuing at a relatively low priority.

Bond vibration takes place on the femtosecond time-scale. Many processes take place at pico- nano- micro- or milli-second time-scales, and some even take as much as a full second. That's a lot of steps to simulate.

[billford]

"Start to finish" data has not yet been completed, even for relatively small proteins.

That's certainly a valid enough objection

THe most popular video shows one full millisecond of folding of NTL9.
https://www.youtube.com/watch?v=gFcp2Xpd29I
The video was(produced a few years ago so you may have seen it. Work is still continuing at a relatively low priority.

I hadn't seen it before, thanks for the link. Exactly the sort of thing I was thinking of, and bookmarked for future reference.

Bond vibration takes place on the femtosecond time-scale. Many processes take place at pico- nano- micro- or milli-second time-scales, and some even take as much as a full second. That's a lot of steps to simulate.

And a lot of video frames to stick together… or, more realistically, deciding which 99.9999% to leave out! I'd guess that the trajectory can't just be sampled at fixed intervals as there may be long periods where little of interest (from a "publicity" point of view) happens interspersed with bursts of activity as parts of the molecule move into critical positions?

[bruce]

You're right. One of the primary problems that FAH had to solve before useful results were obtained was what you call "stick together" Folding has short periods of "events" when a lot happens but they get lost in long periods of "dwell" where bonds just oscillate back and forth making uninteresting motions.

We're desperately off-topic here.

[billford]

We're desperately off-topic here.

Yes, sorry about that. But you've told me what I wanted to know so I'm happy to leave it there.

[P5-133XL]

I have no doubt, that if the capability, precision and accuracy existed then someone would write some software to compare images and thereby have the ability to have a computer condense the unneeded and/or surplus information in the video to more usable levels.

My opinion: Really, are we that far topic? Perhaps it has strayed a bit but there is still a common string attached and it has become more pertinent to folding as it has morphed.

[Jesse_V]

How about this TED talk? http://www.ted.com/talks/ramesh_raskar_ ... per_second
Mirror video: https://www.youtube.com/watch?v=Y_9vd4HWlVA