[-] [email protected] 1 points 8 hours ago

Congrats!! Is your trip still ongoing, or you are done for now?

4
submitted 8 hours ago* (last edited 8 hours ago) by [email protected] to c/[email protected]

This article is from earlier in the year but I missed until now!

Abstract

The emergence of Batrachochytrium salamandrivorans (Bsal) poses an imminent threat to caudate biodiversity worldwide, particularly through anthropogenic-mediated means such as the pet trade. Bsal is a fungal panzootic that has yet to reach the Americas, Africa, and Australia, presenting a significant biosecurity risk to naรฏve amphibian populations lacking the innate immune defenses necessary for combating invasive pathogens. We explored the capability of near-infrared spectroscopy (NIRS) coupled with predictive modeling as a rapid, non-invasive Bsal screening tool in live caudates. Using eastern newts (Notopthalmus viridescens) as a model species, NIR spectra were collected in tandem with dermal swabs used for confirmatory qPCR analysis. We identified that spectral profiles differed significantly by physical location (chin, cloaca, tail, and foot) as well as by Bsal pathogen status (control vs. exposed individuals; pโ€‰<โ€‰0.05). The support vector machine algorithm achieved a mean classification accuracy of 80% and a sensitivity of 92% for discriminating Bsal-control (-) from Bsal-exposed (+) individuals. This approach offers a promising method for identifying Bsal-compromised populations, potentially aiding in early detection and mitigation efforts alongside existing techniques.

[-] [email protected] 1 points 11 hours ago

Alright! Some other tips:

  • Your current microscope is a 160 mm system, so make sure that the objectives are 160 mm and not infinity.
  • Make sure the objectives have an RMS thread
  • Once you move into higher-end objectives, you will have objectives that are specialized. For example, 'phase contrast' objectives have a dark ring inside of them. For the olympus brand their name often ends in 'PL'. These work with bright-field too. My 40/1.30 objective is actually a phase-contrast objective because I did not know this and ChatGPT told me it meant something different ๐Ÿ˜‚ However, the objective does work well for me and I am now considering upgrading to a phase contrast-capable microscope (the BH2), so I made a good choice by accident.
[-] [email protected] 2 points 23 hours ago

I first purchased some Plan objectives from China (40x, 60x), and they are alright. More recently I have been looking into objectives with high numerical apertures to increase the resolution of my images, and I think that the best source of good high-quality used objectives is Ebay. The Olympus apochromatic objectives with high NA are listed for a fraction of their original price, but they are still in the $200 - $500 range, so not very cheap.

[-] [email protected] 3 points 23 hours ago

Wow, those spores are so bumpy, they are very interesting! Thanks for sharing :D

[-] [email protected] 1 points 1 day ago

Ah, I did miss this one! I am not sure that I was notified. This one would absolutely fit with the general theme, as it is a community about sharing useful math-based perspectives.

[-] [email protected] 2 points 2 days ago

Thanks for the idea! That looks very nice, I like how the collection is organized in those storage containers. They look very well preserved so far so your well water + sun protocol seems to be working well. Perhaps I will too start a lichen collection!

[-] [email protected] 8 points 4 days ago

Hello โœŒ๏ธ ๐Ÿ˜„

46
submitted 4 days ago by [email protected] to c/[email protected]

A new species of salamander from Costa Rica, Bolitoglossa chirripoensis, has been described!

Two photos of the newly described salamander, Bolitoglossa chirripoensis

KLANK, JEREMY, et al. "A new species of salamander of the genus Bolitoglossa (Caudata: Plethodontidae) from the highest massif of the Cordillera de Talamanca, Costa Rica." Zootaxa 5642.5 (2025): 427-450.

Research Gate Link

[-] [email protected] 5 points 5 days ago* (last edited 5 days ago)

Not sure how I managed to never hit this species with UV. I would describe the colour as a bright, hot, lipstick pink. I am unsure if this lichen is actually fluorescing or if something else to do with how the pigments show up under UV light - maybe @[email protected] would know. Picture doesnโ€™t quite do it justice.

You are pointing a UV lamp at it which probably sends out 365 nm or 395 nm photons. The lichen is shooting back photons with a broad range of wavelengths, and a lot of ~600 - 750 nm ones (red). So, the UV photons had to be "captured" by some molecular system, the system dissipated some energy, and then re-radiated some of these longer-wavelength photons.

The general term that covers the many different possibilities is "photoluminescence". In this case we can say for sure that the lichen exhibits "UV-induced photoluminescence", because it is re-emitting lower energy (longer-wavelength) photons. It is common to make the connection "photoluminescence" = "fluorescence", but technically fluorescence makes specific claims about how the light is re-emitted (singlet -> singlet emission), and it is not the only luminescence process. Other examples of luminescence are phosphorescence from a triplet state and luminescence via charge-recombination. So, to call it "fluorescence" in the strict sense we need know what the exact pathway is.

That said, when it comes to biological pigments fluorescence is generally the most common pathway. Triplets that live long enough to produce light are generally undesirable as they can react indiscriminately with molecules inside of the cell as well as produce reactive oxygen species, and good phosphorescent materials often combine metals and heavy atoms that are not as abundant in living tissue.

So, knowing nothing else, and seeing that red light comes out when you shine UV/blue light on a lichen, it is generally fair to call it "fluorescence".

Now, if we discuss this specific lichen... I have looked it up and it does get interesting! Do you have it with you? I suspect that its fluorescence might be different during the day than during the night.

I can find online two significant fluorescent components: parietin, which produces the fluorescent yellow pigment, and Chlorophyll a/b, which produces red fluorescence. There is an interesting paper exploring the idea that one functional purpose of parietin's fluorescence is that it can transfer energy to the algae to boost their photosynthesis. Their conclusions in the paper is that the idea is not supported by the evidence, so, a "negative result". It is a fun example of the type of research that is performed in photobiology and also an example to show that even negative results can be interesting enough to be published!

As for the difference between day and night - if what you see is a combination of the fluorescence of parietin and chlorophyll, then the color might change with the day/night cycle. Photosynthetic organisms regulate the flow of excess photon energy towards a safe non-radiative dissipation pathway in response to light. This is called the non-photochemical quenching pathway, and during the day this pathway tends to be active. During the night there is little light, and so this protective pathway shuts-off. This allows more of the absorbed photon energy to flow into the radiative fluorescence pathway, increasing the red fluorescence. You can actually see this easily with plants - you can dark adapt a leaf and then compare its fluorescence with that of a leaf that is being exposed to a bright light. The dark-adapted one will usually show significantly more red fluorescence.

This time you did ask, so I won't apologize for my essay ๐Ÿ˜† But I am a bit sorry I didn't have the time to make it shorter.

[-] [email protected] 7 points 6 days ago

No. I think they both lose more than they gain here. It doesn't make sense as a strategy. Ego clash is a simple explanation.

[-] [email protected] 6 points 6 days ago

Enjoy your holidays!! ๐Ÿ•Š๏ธ

10
submitted 1 week ago by [email protected] to c/[email protected]

cross-posted from: https://mander.xyz/post/31227704

This weekend I did some experiments with turmeric powder. Here are some images of the results, and the description of how to create these microscopic chemical landscapes is given below.

Turmeric powder is a fantastic material to play with. The powder has a high concentration of colored and fluorescent curcuminoids and volatile turmerone oils.

When you use a polar solvent to extract these compounds, what you get is a kind of fluorescent oily resin called a turmeric 'oleoresin'.

The curcuminoids are yellow at acidic and neutral pH, but they become bright red at high pH due to keto-enol tautomerization. There is a lot of cool things you can do with the curcuminoids in terms of photo/electrochemistry.

I have been playing with very simple chemistry under the microscope, and I have noticed that you can create some cool-looking micro-landscapes. During this process you can also see different types of physico-chemical processes happening in real time.

Procedure to do this:

  • Place a few grams of turmeric powder into a glass container
  • Add enough isopropanol to cover the material, and a bit more
  • Mix
  • Wait for the solids to settle
  • Collect a bit of the isopropanol liquid from the top and place on a glass coverslip
  • Wait for the isopropanol to evaporate.

At this time, you can see under the microscope that golden oil droplets have been deposited, and that the surroundings are also yellow. The drops are oleoresins, which consist of curcuminoids suspended in turmerones and other oily compounds. Thin curcuminoid films might also be forming in between these droplets.

  • Add a sprinkle of baking soda crystals (sodium bicarbonate) on top of the coverslip. You can blow on the coverslip if you accidentally add too much.

  • Add a small drop of water, and wait a bit.

At this time you can see that the crystals are dissolving under the microscope, but the colors are not changing. The water and oils are not mixing, and so you get this film of alkaline water surrounding the oil droplets, but nothing is yet really changing.

  • After waiting a few minutes, add a drop of isopropanol.

Now the isopropanol will re-dissolve the oleoresin and mix with the alkaline water. The carbonate ions are now able to react with the curcuminoids, and when they do, they go into the ketone form and instantly turn red. Under the microscope you can see quite dramatic movements of yellow and rad streaking as well as turbulent movements of the baking soda crystals.

  • Wait some time for the liquids to evaporate again

  • You will end up with a landscape that combines yellow resins, red resins, sodium bicarbonate crystals, and several different patterns.


You can vary the parameters - the amount of sodium bicarbonate, the position and size of the drops, you can pre-mix the water and isopropanol, etc. Small changes can drastically affect the resulting landscape.

16
submitted 1 week ago* (last edited 1 week ago) by [email protected] to c/[email protected]

This weekend I did some experiments with turmeric powder. Here are some images of the results, and the description of how to create these microscopic chemical landscapes is given below.

Turmeric powder is a fantastic material to play with. The powder has a high concentration of colored and fluorescent curcuminoids and volatile turmerone oils.

When you use a polar solvent to extract these compounds, what you get is a kind of fluorescent oily resin called a turmeric 'oleoresin'.

The curcuminoids are yellow at acidic and neutral pH, but they become bright red at high pH due to keto-enol tautomerization. There is a lot of cool things you can do with the curcuminoids in terms of photo/electrochemistry.

I have been playing with very simple chemistry under the microscope, and I have noticed that you can create some cool-looking micro-landscapes. During this process you can also see different types of physico-chemical processes happening in real time.

Procedure to do this:

  • Place a few grams of turmeric powder into a glass container
  • Add enough isopropanol to cover the material, and a bit more
  • Mix
  • Wait for the solids to settle
  • Collect a bit of the isopropanol liquid from the top and place on a glass coverslip
  • Wait for the isopropanol to evaporate.

At this time, you can see under the microscope that golden oil droplets have been deposited, and that the surroundings are also yellow. The drops are oleoresins, which consist of curcuminoids suspended in turmerones and other oily compounds. Thin curcuminoid films might also be forming in between these droplets.

  • Add a sprinkle of baking soda crystals (sodium bicarbonate) on top of the coverslip. You can blow on the coverslip if you accidentally add too much.

  • Add a small drop of water, and wait a bit.

At this time you can see that the crystals are dissolving under the microscope, but the colors are not changing. The water and oils are not mixing, and so you get this film of alkaline water surrounding the oil droplets, but nothing is yet really changing.

  • After waiting a few minutes, add a drop of isopropanol.

Now the isopropanol will re-dissolve the oleoresin and mix with the alkaline water. The carbonate ions are now able to react with the curcuminoids, and when they do, they go into the ketone form and instantly turn red. Under the microscope you can see quite dramatic movements of yellow and rad streaking as well as turbulent movements of the baking soda crystals.

  • Wait some time for the liquids to evaporate again

  • You will end up with a landscape that combines yellow resins, red resins, sodium bicarbonate crystals, and several different patterns.


You can vary the parameters - the amount of sodium bicarbonate, the position and size of the drops, you can pre-mix the water and isopropanol, etc. Small changes can drastically affect the resulting landscape.

7
submitted 1 week ago by [email protected] to c/[email protected]

I just learned about hobby and read through some discussions about space weather in the spaceweatherlive forum.

It is not clear to me from those discussions where the data they discuss is coming from.

Are there tools that one can have at home to track space weather events? Through hobby-grade telescopes can one observe solar activity? Are diagnostic radio signals detectable with an SDR? Can an X-ray/gamma burst produce a strong enough diagnostic signal to detect with a radiation detector? Or are there some other type of detectors?

Is the main source of data used for interpreting solar activity patterns as a hobby the data that can be found here: https://www.spaceweatherlive.com/ ?

47
submitted 1 week ago* (last edited 1 week ago) by [email protected] to c/[email protected]

This is a stack of 7 images, you can click on the image to see the full resolution and guess what the subject is :D

The photos were taken using a Nikon D7500 camera connected through a T2 adapter tube with 2X magnification (NDPL-1(2X)). Microscope is the Swift SW380T. The objective is a 4x Plan objective.

For stacking the images together I use three tools: ImageMagick's mogrify to transform from the raw NEF files to .tif, Hugin's align_image_stack function to align the images, and enfuse to blend the images together.

The output .tif file was post-processed using rawtherapee in order to increase local contrast and tune some other parameters.

The process of focus stacking a set of images is rather simple in Linux. The programs above can be installed via the package manager. Then, you copy the raw files to focus-stack into a folder, and run the following sequence of commands:

(1) Convert from RAW to TIF:

mogrify -format tif *NEF

(2) Align images

align_image_stack -a aligned_ -v -m -g 10 -C *.tif

(3) Focus stack

enfuse -o result.tiff --exposure-weight=0 --saturation-weight=0 --contrast-weight=1 --hard-mask aligned_*

Below are the images used for the stack after alignment, for reference:

10
submitted 2 weeks ago by [email protected] to c/[email protected]

The linked video is about the open source 3D printable "Portable Upgradeable Modular and Affordable" (PUMA) microscope. The channel has several videos explaining fundamental concepts in microscopy and showing practical examples.

The github is here: https://github.com/TadPath/PUMA

The microscope can already perform many types of advanced techniques, and it is still being actively developed. The git states that the author is currently working on a motorized XYZ precision CNC stage. These precision stages are usually quite expensive, and they are very interesting because they enable some scanning microscopy techniques.

I am not associated with this in any way, I just watched a few videos and found them interesting enough to share.

46
Cyanobacteria (mander.xyz)
submitted 2 weeks ago* (last edited 2 weeks ago) by [email protected] to c/[email protected]

This specimen came from a slimy film of algae that grew in one of my algal cultures. I think that it is a Nostoc. Objective is 40x/0.65

50
Plant stomata (mander.xyz)
submitted 2 weeks ago* (last edited 2 weeks ago) by [email protected] to c/[email protected]

This image was taken through the 100x oil objective and a 2x camera adapter projecting the image into a Nikon D7500. The sample is a leaf from one of my plants (Dioscorea elephantipes, but I don't think this picture would look very different for other plant species)

The edges of he leaf were already yellowish brown. Here is a photo of that area with much less chlorophyll:

And here is a photo through the 40x objective using oblique illumination:

If you want to see some really fantastic photos of plant stomata I recommend having a look at Rolf Vossen's photographs here: https://microscopyofnature.com/stomata

I am looking through his documentation trying to understand how he managed to get those images. They are spectacular.

48
Emerging trichome (mander.xyz)
submitted 2 weeks ago by [email protected] to c/[email protected]

This is a photograph of a small trichome on the surface of a seedling through the 40x objective. Not sure if it is a happy trichome looking up at what it will become or a sad trichome looking down ๐Ÿ˜† I liked the colors and the scene, reminds me of a painting.

Here is a photo through the 10x:

33
submitted 2 weeks ago* (last edited 2 weeks ago) by [email protected] to c/[email protected]

I prepared a 1:200 dilution of red blood cells using a ~1% NaCl solution. The imaged region contains 4 nano liters of the diluted sample. This image was taken using a 40x objective.

A count is performed by counting the number of red blood cells in a few of these sections, averaging the result, and then converting back to red blood cells per microliter by multiplying times 200 (dilution) and dividing by 0.004 (sampled volume in micoliters).

For this particular sample I estimated 3.8 million red blood cells per micro liter of blood.

I tested a few different types of hemocytometer/Neubauer chambers from China and I can recommend this specific one:

There are some even cheaper alternatives but the lines are very difficult to see.

14
Epithelial cells (mander.xyz)
submitted 2 weeks ago* (last edited 2 weeks ago) by [email protected] to c/[email protected]

I followed the Gram Staining tutorial from this video to prepare a sample of my cheek cells: https://www.youtube.com/watch?v=lMoT-FmhS6A

For preparing the staining solutions I purchased crystal violet, ethanol, potassium iodide, iodine, and an already prepared safranin solution from laboratorium discounter.

The slight 3D effect is achieved by displacing the filter holder to block the light coming from one direction and achieve oblique illumination to cast a shadow (https://www.youtube.com/watch?v=9btIpf5mjyA).

The image is post-processed using Rawtherapee to increase the contrast.

Here is another photo without using the oblique illumination trick, also post-processed with rawtherapee:

view more: next โ€บ

Sal

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