Search found 31 matches

by Martin Parnham
Fri Sep 01, 2023 7:10 am
Forum: Morphology and Behavior
Topic: AC electric fields Paramecia
Replies: 0
Views: 15659

AC electric fields Paramecia

The effect of AC electric fields on cilia / Paramecia is less studied. I used the slide from the last posting but this time with an AC voltage supply. I built an astable circuit to drive it. The frequency can be varied between 1 and 2800 Hz. The peak-to-peak voltage is adjustable. The duty cycle is ...
by Martin Parnham
Fri Sep 01, 2023 7:05 am
Forum: Morphology and Behavior
Topic: DC electric fields - Paramecia
Replies: 0
Views: 711

DC electric fields - Paramecia

Hi folks The Ludloff phenomenon was named after the late Victorian scientist who was one of the first to observe the characteristic change in the motion of lo cilia in response to an applied electric field. In many organisms this results in a sudden change in direction. In order to look at this I cr...
by Martin Parnham
Thu Aug 24, 2023 6:59 am
Forum: Pictures and Videos
Topic: How to post photos
Replies: 5
Views: 738

Re: How to post photos

PS - That's a seriously cool photograph - Martin
by Martin Parnham
Thu Aug 24, 2023 6:57 am
Forum: Pictures and Videos
Topic: How to post photos
Replies: 5
Views: 738

Re: How to post photos

Thank you Chas for your excellent reply. I really don't think I would have got there without it!

Martin
by Martin Parnham
Wed Aug 23, 2023 3:46 pm
Forum: Pictures and Videos
Topic: How to post photos
Replies: 5
Views: 738

How to post photos

Hi folks - Had a look around the forum FAQ's but could do with a little more help with posting photo's and having them show as a picture (not a link) in a posting. I think it involves hosting the photos on a publicly accessible site (?) then using the 'img tag' in the post (?). Not clear about eithe...
by Martin Parnham
Fri Aug 04, 2023 4:35 pm
Forum: Morphology and Behavior
Topic: Vorticella long stalks
Replies: 3
Views: 1227

Re: Vorticella long stalks

Very interesting references - thank you. I would never have found them. 4150 ! I have never seen any remotely that length. I suspect stalk length is determined by a complex interplay of factors, genetics, food availability, water flow, local topography, predation rates etc. I have found techniques o...
by Martin Parnham
Mon Jul 31, 2023 4:28 pm
Forum: Morphology and Behavior
Topic: Vorticella long stalks
Replies: 3
Views: 1227

Vorticella long stalks

Hi folks - Not very original but hopefully of passing interest. My latest water sample from a new area contained Vorticella with notably long stalks. Initial mounts with my usual gentle cover slip squash, produced long headless stalks. I then made thicker water mounts (no squash, just the weight of ...
by Martin Parnham
Thu Mar 09, 2023 9:27 am
Forum: Pictures and Videos
Topic: Vorticella campanula
Replies: 4
Views: 579

Re: Vorticella campanula

Lovely video - nice to see the interpretation / labels - thank you.

Martin
by Martin Parnham
Thu Feb 23, 2023 6:46 pm
Forum: Pictures and Videos
Topic: Pompholyxophrys, another scaly amoeba
Replies: 4
Views: 578

Re: Pompholyxophrys, another scaly amoeba

Lovely image, I wonder how the perles are made, what holds them together, what are the advantages of this protection system - many questions - must get busy on the net.

Martin
by Martin Parnham
Tue Feb 14, 2023 9:18 am
Forum: Morphology and Behavior
Topic: Contractile vacuole pore
Replies: 1
Views: 1279

Contractile vacuole pore

Hi Folks - Winter is still depleting life in my usual water sources, so carrying on with observations on Paramecium from the jam jar on the windowsill. I thought it would be interesting to try observe and record/measure the contractile vacuole pore. The CV is the osmo-regulatory organelle which remo...
by Martin Parnham
Fri Feb 03, 2023 4:25 pm
Forum: Pictures and Videos
Topic: Predators: Actinosphaerium
Replies: 4
Views: 810

Re: Predators: Actinosphaerium

Terrific -very well done. Must try and find one!
Martin
by Martin Parnham
Tue Jan 24, 2023 6:44 pm
Forum: Pictures and Videos
Topic: Chilling out with a Paramecium !
Replies: 6
Views: 1084

Re: Chilling out with a Paramecium !

Thanks for the camera tips I will definitely look at those other Samsung phones. One of the main reasons I post my system specs is to hopefully show people that you can get fairly respectable results with quite modest equipment. My scope is a good quality but 'ordinary' bright field device. My phone...
by Martin Parnham
Sun Jan 22, 2023 4:23 pm
Forum: Pictures and Videos
Topic: Chilling out with a Paramecium !
Replies: 6
Views: 1084

Re: Chilling out with a Paramecium !

Thank you - This might be heresy, but in many respects I find my phone better than my dedicated 5 megapixel USB 'microscope camera' ! It can shoot HD at 30 fps. Its light sensitivity and colour response is excellent, its contrast is also excellent. Its focus is precise. I suppose its main limitation...
by Martin Parnham
Sun Jan 22, 2023 9:47 am
Forum: Pictures and Videos
Topic: Chilling out with a Paramecium !
Replies: 6
Views: 1084

Chilling out with a Paramecium !

Hi folks - I created this video to show food vacuole formation and cytoplasmic streaming in Paramecium. Without slowing them down this is very difficult to see. In order to do this I used a 3% Methyl-Cellulose solution. One drop on a slide, one drop alongside of the sample water and mixed with a mou...
by Martin Parnham
Tue Jan 17, 2023 5:33 pm
Forum: Morphology and Behavior
Topic: Paramecia self defense
Replies: 3
Views: 3716

Paramecia self defense

Hi Folks - My in-house (literally!) Paramecium jar is thriving so I thought I would try some classic experiments / observations on them. Paramecia like many Ciliates have organelles called Trichocysts. The filamentous ones found in Paramecia are thought to be used largely for self defense mostly aga...
by Martin Parnham
Sat Jan 07, 2023 4:14 pm
Forum: Miscellaneous
Topic: Database of 200,000 3D cell images for understanding cellular building blocks
Replies: 2
Views: 1105

Re: Database of 200,000 3D cell images for understanding cellular building blocks

Thanks for posting this - very interesting. Quite a feat of data gathering and analysis.I wonder if this level of information will ever be available for free living single cell ciliates? I would be very interesting to see their cytoskeletons at this level of detail.

Martin
by Martin Parnham
Wed Dec 28, 2022 5:55 pm
Forum: Pictures and Videos
Topic: Wandering around a drop of fresh water with oil immersion
Replies: 8
Views: 907

Re: Wandering around a drop of fresh water with oil immersion

Thank you - a very informative reply.
Martin
by Martin Parnham
Tue Dec 27, 2022 5:29 pm
Forum: Pictures and Videos
Topic: Wandering around a drop of fresh water with oil immersion
Replies: 8
Views: 907

Re: Wandering around a drop of fresh water with oil immersion

Very nice, clear and no hint of halo's. I was wondering what set up you are using.?
thank you
Martin
by Martin Parnham
Sun Dec 25, 2022 12:11 pm
Forum: Pictures and Videos
Topic: Frontonia Contractile Vacuole formation.
Replies: 4
Views: 673

Re: Frontonia Contractile Vacuole formation.

Thank you Bruce - In truth I was clutching at straws! I filmed it a few weeks ago and hesitated to post it as I was not sure what I had seen.
You live and learn
Martin
by Martin Parnham
Thu Dec 22, 2022 1:14 pm
Forum: Pictures and Videos
Topic: Frontonia Contractile Vacuole formation.
Replies: 4
Views: 673

Re: Frontonia Contractile Vacuole formation.

Thanks Dom - As I am sure you have found you need a lot of luck to find the little critters in the right position, and still enough to actually film internal activity.

Martin
by Martin Parnham
Wed Dec 21, 2022 5:51 pm
Forum: Pictures and Videos
Topic: Frontonia Contractile Vacuole formation.
Replies: 4
Views: 673

Frontonia Contractile Vacuole formation.

Hi folks - A slow moving Frontonia in a good position to video. Its contractile vacuole formation is very clear. They pump out excess water. The lower water potential of the cytoplasm compared to the surrounding water causes a continuous net flow into the cell, this must be removed or the cell will ...
by Martin Parnham
Sun Dec 11, 2022 12:06 pm
Forum: Pictures and Videos
Topic: Vorticella slowed by a strobe light
Replies: 9
Views: 1184

Re: Vorticella slowed by a strobe light

Sorry to here that Chas - Never the less that video was spot on. You have inspired me to have a go, and I now have some idea of the required frequency range for the strobe.

Thank you
Martin
by Martin Parnham
Sat Dec 10, 2022 5:47 pm
Forum: Pictures and Videos
Topic: Vorticella slowed by a strobe light
Replies: 9
Views: 1184

Re: Vorticella slowed by a strobe light

Hi Chas
Excellent video - fascinating, would you know what frequency your light was strobing at?
Martin
by Martin Parnham
Fri Dec 09, 2022 5:57 pm
Forum: Pictures and Videos
Topic: Feeding in Rotifer and Paramecium
Replies: 0
Views: 408

Feeding in Rotifer and Paramecium

Hi folks - I thought it might be interesting to attempt a comparison between the feeding vortices produced by a Metazoan Rotifer with a Protozoan Paramecium. I Used the same technique I outlined in the posting below - https://www.microbehunter.com/microscopy-forum/viewtopic.php?f=6&t=17439 After som...
by Martin Parnham
Mon Dec 05, 2022 6:45 pm
Forum: Specimens, samples and slides
Topic: Pond sample question
Replies: 12
Views: 4191

Re: Pond sample question

Hi - For a while I maintained a reasonably successful indoor 'pond' in a large glass vase on an east facing windowsill. I was conscious of trying to avoid solute accumulation. As the water evaporated I topped up with rain water. In addition every couple of weeks I removed about a fifth of the old wa...
by Martin Parnham
Thu Dec 01, 2022 7:48 pm
Forum: Pictures and Videos
Topic: feeding vortices
Replies: 3
Views: 695

Re: feeding vortices

Hi Chas - thanks for that. I think you are spot on with the viscosity issue. I think that generating vortices such as many ciliates produce must be a tremendously energetic process. I suspect that a very significant portion of their ATP generation is dedicated to it. Its one of those evolutionary' c...
by Martin Parnham
Wed Nov 30, 2022 4:37 pm
Forum: Pictures and Videos
Topic: feeding vortices
Replies: 3
Views: 695

feeding vortices

Hi folks - You often get glimpses of the vortices generated by Ciliates whilst moving / feeding. You need a bit of luck and enough 'small bits' to be swept up to see the motion of the water. I have been experimenting with adding particles that would make observation clearer. I have tried various pow...
by Martin Parnham
Mon Nov 28, 2022 7:57 pm
Forum: About the website, the magazine and this forum
Topic: Embedding Youtube videos
Replies: 4
Views: 2780

Re: Embedding Youtube videos

Thank you both very much - I will give it a go. Very new to this forum.

Martin
by Martin Parnham
Sun Nov 27, 2022 7:45 pm
Forum: About the website, the magazine and this forum
Topic: Embedding Youtube videos
Replies: 4
Views: 2780

Embedding Youtube videos

Hi - I was wondering how to embed Youtube videos. I followed the instructions on using this forum. It asked me to follow the instructions in an image which I can't seem to load?

Thank you

Martin
by Martin Parnham
Sun Oct 16, 2022 4:32 pm
Forum: Morphology and Behavior
Topic: Biocrystallization
Replies: 2
Views: 2305

Biocrystallization

Hi Folks - I am sure many of us have seen microbes lit up like Christmas trees under polarized light, often Ciliates. For example I took this snap this morning of a Paramecium (sorry for the glare!) - This article provides some fascinating insights into why this occurs. After reading this I suspect ...