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ultra fast laser spectroscopy


fredreload

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Alright, there is a person standing there. I am intending to take a high resolution neuronal live cell imaging of the person non-invasively in real time.

I've looked through all types of microscopy techniques, which, you know, requires you to look through a microscope without the neurons being blocked by the skull. With the finest detail being an electron microscope that is, but to look through a sample, you would need to generate a 3D mesh, so I look into spectroscopy, which generates a hyperspectral data based on the Raman spectroscopy if you know what I am talking about.

So  simple laser spectroscopy, how detail does it get? There is Raman spectroscopy and all kinds but I eventually hit plasmonic resonance imaging, which is by far the most detailed laser imaging you can find that is without speed. The resolution detail gets to a few microns.

And then I found femtosecond spectroscopy, the group that belongs to ultra fast laser spectroscopy, and their neuronal images resolution is by far the most promising.

My question is why do you need a femtosecond speed laser for high resolution? Does a stand still laser impossible to generate a high resolution image?

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2 hours ago, fredreload said:

Alright, there is a person standing there. I am intending to take a high resolution neuronal live cell imaging of the person non-invasively in real time.

I've looked through all types of microscopy techniques, which, you know, requires you to look through a microscope without the neurons being blocked by the skull. With the finest detail being an electron microscope that is, but to look through a sample, you would need to generate a 3D mesh, so I look into spectroscopy, which generates a hyperspectral data based on the Raman spectroscopy if you know what I am talking about.

So  simple laser spectroscopy, how detail does it get? There is Raman spectroscopy and all kinds but I eventually hit plasmonic resonance imaging, which is by far the most detailed laser imaging you can find that is without speed. The resolution detail gets to a few microns.

And then I found femtosecond spectroscopy, the group that belongs to ultra fast laser spectroscopy, and their neuronal images resolution is by far the most promising.

My question is why do you need a femtosecond speed laser for high resolution? Does a stand still laser impossible to generate a high resolution image?

Laser spectroscopy precision is typically referring to the energy or time domain, not spatial resolution.

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It's not my field but...

If I shine a fast pulse of light at, for example, my hand and I look at it through a microscope focussed  on a bone somewhere in the tissue I will mainly see a blur.

But if I put a shutter on the microscope and only open it at the right time for photons to have left the laser, reached the bone + bounced straight back without scattering, then I will see a clearer image. Obviously that image won't be very bright, but I can repeat the process and sum the images.

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8 minutes ago, swansont said:

Laser spectroscopy precision is typically referring to the energy or time domain, not spatial resolution.

Ya you are correct, it is about the time domain in mainly capturing very fast processes like enzyme interactions. I am taking a liking on SEM and cryo-electron spectroscopy, pretty much all methods of electron microscopy as it generates a very detailed image.

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2 hours ago, fredreload said:

Ya you are correct, it is about the time domain in mainly capturing very fast processes like enzyme interactions. I am taking a liking on SEM and cryo-electron spectroscopy, pretty much all methods of electron microscopy as it generates a very detailed image.

With electrons you have a wavelength that is h/p, which can be quite small.

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On 8/30/2018 at 8:07 PM, swansont said:

With electrons you have a wavelength that is h/p, which can be quite small.

Alright, here is my conclusion, let me know if it is correct :D. For electromagnetic radiation(light photon) to penetrate tissue it needs to have a really high frequency, such as the x-rays. Like wise for electron spectroscopy to image the brain tissue in vivo it needs to have a high frequency too, else it would stop at the skin, or the skull.

To fix this. An ultrafast electron microscopy could be used, one at a femtosecond scale to generate a high frequency electron wave capable of penetrating the tissue. Just like how a femtosecond laser(photon) could be used to generate high frequency x-ray.

I am looking for the difference between a photon laser and an electron laser, I hope I made the correct speculation. Please feel free to correct my idea

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11 hours ago, swansont said:

Ultrafast refers to the pulse duration, not the energy. A short pulse does not mean you have a short wavelength.

i.e. You can have a femtosecond pulse at a visible or IR wavelegth 

Thanks for the clarification, I was wondering about that too pulse vs wavelength. In this case, is it possible to generate a high frequency electron wave to examine the tissue?

https://en.wikipedia.org/wiki/Electromagnetic_electron_wave

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1 hour ago, John Cuthber said:

What was the question?

I need a detailed image of someone's brain neurons and synapses in real time. It has to be in vivo and non-invasive so the standard microscopy technique where you need to open someone's brain and skull is out of the question, that leaves me with spectroscopy technique like Raman spectroscopy.

So I've studied(glance through) most spectroscopy technique that could map the neurons such as the infrared spectroscopy, but the image resolution is in the micro meter scale, so you cannot image the neurons clearly. The plasmonic resonance imaging is also in the micro meter scale. The methods stated above is using light photons as a medium(electromagnetic radiation).

So what could generate a super resolution image in the nanometer scale, I turned to electron microscope as it generates a very detailed image because of its wavelength property. And thus electron spectroscopy with high frequency alternating current to penetrate the tissue and image the neurons and synapses. This is my speculation of what could generate a nano scale image of the brain and neurons.

So the question is, what spectroscopy technique (photon/electron) could generate a clear image of the neurons and synapses (in nano scale resolution) and nerve signals running in real time in vivo non-invasively?

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3 hours ago, John Cuthber said:

I'm fairly sure that's an impossible goal.

A pulse with a duration of a few femtoseconds is longer than a micron anyway.

Oh ya? How does this guy gets it to work then = =. Difference between two high frequency alternating current to generate atomic resolution microscopy.

https://aip.scitation.org/doi/abs/10.1063/1.1149922

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3 hours ago, fredreload said:

I need a detailed image of someone's brain neurons and synapses in real time. It has to be in vivo and non-invasive so the standard microscopy technique where you need to open someone's brain and skull is out of the question, that leaves me with spectroscopy technique like Raman spectroscopy.

So I've studied(glance through) most spectroscopy technique that could map the neurons such as the infrared spectroscopy, but the image resolution is in the micro meter scale, so you cannot image the neurons clearly. The plasmonic resonance imaging is also in the micro meter scale. The methods stated above is using light photons as a medium(electromagnetic radiation).

So what could generate a super resolution image in the nanometer scale, I turned to electron microscope as it generates a very detailed image because of its wavelength property. And thus electron spectroscopy with high frequency alternating current to penetrate the tissue and image the neurons and synapses. This is my speculation of what could generate a nano scale image of the brain and neurons.

So the question is, what spectroscopy technique (photon/electron) could generate a clear image of the neurons and synapses (in nano scale resolution) and nerve signals running in real time in vivo non-invasively?

I hope you realize that electron microscopes require their sample to be in a vacuum, and (from my limited experience) the procedure is to coat them with a  thin layer (a few atoms thick, at most) of metal.

And you only image the surface, because electrons are easily deflected when passing through bulk material.

Sub-surface optical imaging is going to be a problem with an opaque target.

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7 minutes ago, swansont said:

I hope you realize that electron microscopes require their sample to be in a vacuum, and (from my limited experience) the procedure is to coat them with a  thin layer (a few atoms thick, at most) of metal.

And you only image the surface, because electrons are easily deflected when passing through bulk material.

Yes I know, that's why I am trying to find a way to have the electron pass through the sample(tissue) in which I compared it to light(photon) at high frequency becomes x-ray which pass through the tissue. Thereby increasing the frequency of electron as an alternating current of high frequency to pass through the skin, lock on the brain's neurons and synapses and generate an image. Sounds ridiculous I know, this is based on my speculation.

 

P.S Alternating current of high frequency does go through tissue, like the Tesla coil

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5 minutes ago, fredreload said:

Yes I know, that's why I am trying to find a way to have the electron pass through the sample(tissue) in which

You will not find a way to do that.

Electrons don't go through solid material (they barely go through air).

6 minutes ago, fredreload said:

P.S Alternating current of high frequency does go through tissue

Actually it goes  through the surface, rather than the bulk

https://en.wikipedia.org/wiki/Skin_effect

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8 minutes ago, John Cuthber said:

You will not find a way to do that.

Electrons don't go through solid material (they barely go through air).

Actually it goes  through the surface, rather than the bulk

https://en.wikipedia.org/wiki/Skin_effect

You're right, I guess it's back to square one. Probably a really strong electric field or magnetic field.  So you propose that it is not possible to get a nano scale resolution of the brain in vivo?

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1 hour ago, fredreload said:

Yes I know, that's why I am trying to find a way to have the electron pass through the sample(tissue) in which I compared it to light(photon) at high frequency becomes x-ray which pass through the tissue. Thereby increasing the frequency of electron as an alternating current of high frequency to pass through the skin, lock on the brain's neurons and synapses and generate an image. Sounds ridiculous I know, this is based on my speculation.

 

P.S Alternating current of high frequency does go through tissue, like the Tesla coil

Electrons are charged, which make them behave quite differently than photons in many regards.

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11 hours ago, swansont said:

Electrons are charged, which make them behave quite differently than photons in many regards.

Ya, these things are overrated, it doesn't feel like my consciousness would go anywhere except that one time. Most of the time it just produce headache and brain damage. But you can't get to the consciousness without entering the head first lol

 

P.S Slap the money

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23 hours ago, swansont said:

Electrons are charged, which make them behave quite differently than photons in many regards.

Alright I cracked it. I found this article here from Harvard. The article says that pretty much a high resolution image could be generated from having a nanometer magnet close to the desired source.

My idea is to mimick a nanometer magnet with electromagntic radiation because an electromagnetic radiation is composed of a magnetic field and an electric field. When this electromagnetic radiation pass through the body, bang you got nanometer magnet pass through the body. This magnetic field would create a magnetic gradient and generate a nanometer resolution image based on the MRI principle :D. Haven't worked on the receiver part

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3 hours ago, fredreload said:

Alright I cracked it. I found this article here from Harvard. The article says that pretty much a high resolution image could be generated from having a nanometer magnet close to the desired source.

My idea is to mimick a nanometer magnet with electromagntic radiation because an electromagnetic radiation is composed of a magnetic field and an electric field. 

How? 

NMR/MRI requires a strong magnetic field gradient. How are you going to do that with photons?

"magnet can produce a magnetic field gradient 100 000 times larger than even the most powerful conventional systems."

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