Рет қаралды 248
How did I record this?
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Please enjoy this video made using my Razer Phone 2 and Nikon Eclipse E200 Student Microscope at 20x, 40x, 100x and 400x (2x, 4x, 10x, and 40x objectives). The Razer Phone 2 is recording at 2x magnification, 60fps at 4K resolution.
Darkfield
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The background in most of the video is black because I used a microscopy technique called "darkfield" (or dark-field/dark field). This was achieved with a 3D-printed darkfield conversion kit for the E200 purchased on eBay.ca. The kit consists of a cylindrical insert for the Nikon 1.25 Abbe Condenser and various filters. I used two of the supplied filters, one on the top of the insert, and one at the bottom and this was the result. I think it turned out great, don't you?
Contents of the video
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I used the following guide on collecting tardigrades (from lichen):
mymicroscopicw...
Here is another guide (with additional information and links):
serc.carleton....
More about tardigrades, from (blogs.nwic.edu/...) + (esdac.jrc.ec.e... page 100):
In 1773, a German pastor, Johann August Ephraim Goeze
(1731-1793), was the first to describe a new animal in the book
“Herrn Karl Bonnets Abhandlungen aus der Insektologie”: “…
strange because of its extraordinary anatomy and at first glance its
appearance has a strong resemblance to a little bear. It is because
of this I will name them small water bears…” Goeze also included
the first drawing of a tardigrade in this book (Fig. VI.I).
Six years after the publication of Goeze, the famous naturalist
Lazzaro Spallanzani (1729-1799) made the first scientific
description of the water bear. Since then they have been called
tardigrades. The name refers to the animal’s slow movements
(Lat. tardus - slow, grado - walker).
Sexual reproduction or mating takes place, but observations
are really rare. However, many species are parthenogentic
(i.e. the ovum does not require fertilisation to develop into a
new individual); therefore no males are known. This may be an
evolutionary advantage for colonisation of new habitats as a single
female is able to establish a new population. Many tardigrades
lay freely single eggs with a miscellaneous egg-shell morphology
(Fig. VI.V). But there are also species which lay egg clutches into
the exuvium after molting.
...
Due to their ability to enter a cryptobiotic state (similar to an
extreme form of hibernation whereby all metabolism stops) at
any developmental stage, tardigrades are capable of surviving
extreme conditions for very long periods of time and are able to
extend their lifespan significantly.
...
a form known as a tun (from the German word “Tönnchen”) (Fig.
VI.VI) during periods of desiccation. This is an ametabolic state;
a state without visible signs of life. In this state they are able to
survive exposures to extreme temperatures over 100°C, they
are freezing tolerant and can also survive ionizing radiation, and
high pressure. Tardigrades have even been shown to be able to
survive in the vacuum of open space.
...
Currently, the
longest known observation of an extended lifespan in the tun
state was 20 years.
Due to the fact that tardigrades show extraordinary tolerances
to a range of physical extremes they are now being used as a
new model organism to study mechanisms of preservation in
several fields of research and applied technologies. Tardigrades
may eventually tell us something fundamental about the nature
of life itself.
Tardigrade anatomy:
projects.ncsu....
askabiologist....
Tardigrade Eggs:
askabiologist....
www.eeob.iasta...
www2.palomar.e...
Ocular Micrometer Calibration
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The small ruler visible in the video is called an ocular micrometer. It is calibrated using a special slide called a "slide micrometer"--clever!
The calibration I performed on Sunday June 9, 2019 yielded the approximate values below. Between each whole number on the ocular micrometer (called an "ocular unit" divided into 10 "ocular divisions"), there are:
20x: 0.500 mm (approx.) per ocular unit
40x: 0.250 mm (approx.) per ocular unit
100x: 0.099 mm (approx.) per ocular unit
400x: 0.025 mm (approx.) per ocular unit
You can use these calibrations to give you a rough idea of how large any object you see in the videos is, you only need to use a little math! Cool right?
Music
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"Spin Spin Sugar" (Live) by Sneaker Pimps ( • Sneaker Pimps live - 0... )