Specimen suggestions to show growth over time

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jimduk
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Joined: Wed Mar 03, 2021 7:16 pm

Specimen suggestions to show growth over time

#1 Post by jimduk » Wed Mar 03, 2021 7:28 pm

Hi,
I'm building a prototype XY stage, where the intention is to be able to have a repeatable positioning accuracy at the submicrometre level ( maybe 200 nanometres or below)

I'm looking for suggestions of specimens/ slides where if i revisit a a set of points over time, we will be able to show we have gone back to the same point, but also show the change at that point

e.g. one example may be crystal growth - go back to 5 or 10 positions over time, see how the crystal has grown there

I'm using a pretty basic microscope (Swift380T, 40x or 10x, 6Mp or 20MP camera, illuminated from above or below) and have some simple stains but am fairly new to this

Do you have suggestions of good/ interesting specimens I can prepare which will 'change' over time. timescale is preferably seconds minutes or hours, not days

Things I'm thinking of include maybe some crystallisation, or some decay or maybe something organic clustering on something inorganic or ..... Something that takes a decent clear picture and is fairly easy to set up on a slide with cover slip. Useful real world example would be great, but anything that proves the concept we can go back to a place with micron accuracy and something has changed ( kind of focus stacking over time)

MichaelG.
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Location: North Wales

Re: Specimen suggestions to show growth over time

#2 Post by MichaelG. » Wed Mar 03, 2021 9:35 pm

Your project sounds very interesting ... and it brought a memory back from 1969

Have a look at magazine page 199 [which is pdf page 41] here:
https://worldradiohistory.com/UK/Practi ... 969-03.pdf

The little ‘Random Pulse Noise Cell’ was a work of genius ... and similar ideas are discussed in recent literature.

Wow ... I have lived to see History made and rediscovered !!


MichaelG.
Too many 'projects'

jimduk
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Re: Specimen suggestions to show growth over time

#3 Post by jimduk » Wed Mar 03, 2021 10:13 pm

Wow, thank you. So I think you are talking about the silver nitrate cell, the idea that I could try and grow some silver nitrate strands.

As for the magazine, very interesting. Liked the Sinclair radio adverts, and also the Emma article, I spent a few months building behaviour based robots at Edinburgh, but not as analog or interesting as the Emma
Thanks again

MikeBradley
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Location: Sunshine Coast, BC, Canada

Re: Specimen suggestions to show growth over time

#4 Post by MikeBradley » Thu Mar 04, 2021 5:22 am

EMMA - I still have my "evolved" version all these years later, I replaced the discrete components of the original design with a Rug Warrior MC68H system and changed the motors too but usually included the AgNO3 cell. I always turned my nose up at the "pseudo-random" digital generators in other robotic designs when I had a truly random system in mine. I'm glad to hear that these electro-chemical systems are enjoying a resurgence. EMMA was a superb introduction for this nerdy teenager to the potential of implementing simple logic alongside other semiconductor techniques, all using discrete components of course!
Michael
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MicroBob
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Re: Specimen suggestions to show growth over time

#5 Post by MicroBob » Thu Mar 04, 2021 7:09 am

MichaelG. wrote:
Wed Mar 03, 2021 9:35 pm
Have a look at magazine page 199 [which is pdf page 41] here:
https://worldradiohistory.com/UK/Practi ... 969-03.pdf
Electronics really was a popular hobby in these decades with shops and kits and magazines in many languages. When I became a teenager electonics as a hobby was more and more replaced by home computing and RC models were also very popular.
Until a few years ago I had a Commodore PET 2001 in working condition. It's basic interpreter had a random numer generator too - but only going through a list of ever same numbers!

Bob

MichaelG.
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Re: Specimen suggestions to show growth over time

#6 Post by MichaelG. » Thu Mar 04, 2021 9:27 am

Glad this ‘sparked’ some interest

Here are a couple of more recent references:
https://www.sciencealert.com/scientists ... -chemistry
https://phys.org/news/2020-02-crystals-random.html

and a nod to EMMA here:
https://forum.arduino.cc/index.php?topic=3627.0

A flattened version of this little cell would, I think, make an excellent subject on jimduk’s stage

MichaelG.
Too many 'projects'

jimduk
Posts: 4
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Re: Specimen suggestions to show growth over time

#7 Post by jimduk » Thu Mar 04, 2021 10:16 am

Thanks for the discussion, I've ordered some silver nitrate, may try it with small scraps of copper on a slide, or with a voltage

Any other suggestions for microscope slides which may 'grow' or change over time, but with some permanent re-visitable features?

Is there any kind of mold which keeps growing under a cover slip, or something which decays (I've seen the onion cells and salt water on the site, that may be worth trying) or some sort of diffusion
Cheers

MichaelG.
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Location: North Wales

Re: Specimen suggestions to show growth over time

#8 Post by MichaelG. » Thu Mar 04, 2021 11:04 am

jimduk wrote:
Thu Mar 04, 2021 10:16 am
Any other suggestions for microscope slides which may 'grow' or change over time, but with some permanent re-visitable features?
.

This attracted no comment, but might be ‘right up your street’

https://www.microbehunter.com/microscop ... old#p98747

MichaelG.
Too many 'projects'

MicroBob
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Re: Specimen suggestions to show growth over time

#9 Post by MicroBob » Thu Mar 04, 2021 11:38 am

You might consider a micro-aquarium slide. Some rotifiers and ciliares move around quickly, but hydras, stentors and desmids are more or less fixed and catch prey or divide.

jimduk
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Re: Specimen suggestions to show growth over time

#10 Post by jimduk » Thu Mar 04, 2021 2:17 pm

Thanks chaps, will post some examples back up here in a week or so when I've got something working,
much appreciated

PeteM
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Re: Specimen suggestions to show growth over time

#11 Post by PeteM » Thu Mar 04, 2021 3:31 pm

Jim - Electrophoresis is another option.

Rust or another oxidation reaction (rotting?) might proceed rapidly enough.

Chemical crystals under polarization evolve as the solvent dries over time.

Given that they're fast-growing and used to show cell mitosis, if you find a way to grow onion root tips under a cover slip that might be cool.

And you'll become an Internet sensation if you become the guy who actually watches paint dry. Like_watching_paint_dry.com? You could cheat and use a heat gun or hair dryer.

Keep us posted with images.

MichaelG.
Posts: 3976
Joined: Mon Apr 10, 2017 8:24 am
Location: North Wales

Re: Specimen suggestions to show growth over time

#12 Post by MichaelG. » Sat Mar 13, 2021 10:39 am

jimduk

I saw this, today ... and thought of you !
https://theconversation.com/the-secret- ... und-156610

MichaelG.
Too many 'projects'

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