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Why Science Nerds Wear Glasses.

24 Oct

Ever wonder why science nerds wear glasses?
Recently, a contact lens wearing lass was infected by an amoeba which was infected by a virus which was infected by a virophage which was infected by a parasitic piece of DNA called a transpoviron. It’s like a microbial inception. (This article originally appeared on io9.com)

Woman with eye infection had an entire microbial ecosystem in her contact lens solution


by George Dvorsky

There’s a reason why optometrists say you should regularly replenish your contact lens solution and throw out your lenses after the expiry date. Last year, a young woman contracted an eye infection after using tap water to dilute her cleaning solution, and while wearing contact lenses that were two months past their expiry date. Subsequent analysis of her lens solution revealed an entire cornucopia of microorganisms that were spawned from a single amoeba, including a giant virus that was also infected with a virus — and a piece of DNA that was capable of infecting both of them.

Thankfully, the woman’s condition, keratitis, was not serious and was easily treatable — but the subsequent analysis of her contaminated lens solution was quite revealing, if not disturbing.

The research, which was conducted by Bernard La Scola and Christelle Desnues, was initially concerned with an amoeba they found in the fluid. But after looking at the amoeba more carefully, the researchers discovered that it hosted two different microorganisms, including a giant virus that had never been seen before (what is now called the Lentille virus).

This Lentille virus, after infecting the amoeba, created a kind of “virus factory” where its genetic material was copied, thus spawning new viruses that were architected from its genetic script.

Now, if this wasn’t surprising enough, the researchers also discovered that the Lentille virus was also infected with a virus, what’s called a virophage. This virus-within-a-virus, named Sputnik 2, is only capable of reproducing in cells infected by other viruses (in this case, the infected amoeba). Amoebas that are infected with this virus continue to release virophage particles, which means the virus can continue to infect other amoebas on their own.

But there’s still more: Both the giant Lentille virus and Sputnik 2 virophage contained even smaller parasites called transpovirons — highly mobile chunks of DNA that can relocate themselves into the genomes of viruses and tuck themselves away inside of virophages.

So, in summary, the researchers discovered that a transmissible DNA sequence managed to find its way into a virophage (and potentially the giant virus itself), which in turn latched onto a giant virus, which then infected an amoeba — an amoeba that eventually found its way into the eye of a 17-year old girl.
You can read the entire study at PNAS.

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Just When You Thought It Was Safe…

22 May

Adorable Dinosaurs

5 Apr

Hard evidence that giant tyrannosaurs were cuter than you ever thought possible


by Annalee Newitz of i09.

Imagine a tyrannosaur weighing one and a half tons, completely covered in soft, downy plumage. Even its tail is fluffy with feathers. Though we’ve known for a while that many dinosaurs were covered in feathers, a group of Chinese researchers have now provided direct evidence that gigantic, deadly tyrannosaurs might have looked a bit like wuffly birds. Three nearly complete, well-preserved fossils give us a glimpse of tyrannosaurs the way we’ve never seen them before.

The fossils were found in the Liaoning Province in China, in the “Yixian formation,” a package of rocks that is known to date to the early Cretaceous period. Described today in Nature magazine, the creatures are in the subgroup Tyrannosauroidea, which is part of the Therapod family that includes both the iconic T. Rex as well as winged dinosaurs who eventually evolved into today’s birds. The animals that paleontologist Xing Xu and colleagues dubbed Yutyrannus huali would have been quite large for tyrannosaurs (the largest, an adult, likely weighed almost 1.5 tons) and were probably the apex predators of their region.

The researchers write:

Most significantly, Y. huali bears long filamentous feathers, thus providing direct evidence for the presence of extensively feathered gigantic dinosaurs and offering new insights into early feather evolution.

Hard evidence that giant tyrannosaurs were cuter than you ever thought possible

In these fossils, you can see the long, flowing tail feathers that would have trailed out behind these huge beasts. The question that Xu and his team ask is why these large dinosaurs would have needed feathers. Usually feathers and fur are used for insulation, but creatures with large bodies often lose their hair because they generate enough body heat that insulation is unnecessary. Y. huali is by far the largest dinosaur known to have had feathers, and there is plenty of fossil evidence that other large tyrannosaurs had scaly skin.

The researchers speculate that these tyrannosaurs may have been adapted to extremely cold environments, while other tyrannosaurs lived in more tropical regions. Another possibility is thatY. huali didn’t have feathers all over its body — it might have had some areas of bright plumage for display, but scales elsewhere.

Read the whole scientific article in Nature

Microscopy Monday {No.4}

2 Apr

An antique microscope slide of a thin section of diseased ivory. (15x)

Stephen Nagy is a psychiatrist and amateur microscopist who took this image specifically for entry into the contest. It shows how a disease process can alter structure of ivory, creating strange and beautiful evocative shapes, which lead to people imagining that they see something else in the image. The image was taken using standard polarizing light techniques, with crossed polarizing filters, a first-order red plate, and an additional compensating plate made of ordinary cellophane. Image-stitching technology though Adobe Photoshop that created this composite of sixteen separate exposures or images, seamlessly merging them into one image which shows much more of the ivory’s structure.

Image by Stephen Nagy.


The Truth About Dinosaurs

1 Apr

Mr. T-Rex always did have a hard time with a shovel, due to their awkwardly short arms.
Poor T-Rex.

 

Happy April Fools Day!

1 Apr

Happy April Fools Day, Internet!
In celebration of the trickiest of days, I present to you random “science facts” floating around the internet, all of which are completely, completely untrue.


Now excuse me while I go plant some rice grains.
I’ll be sure to wash up with kitten saliva afterwards.
Speaking of which, where on earth does a person get “one glass of cat salvia?” Can I get that at the local Safeway, or do I have to special order it online?

Meryl Streep Is A Mimic Octopus

27 Mar

The mimic octopus, Thaumoctopus mimicus, can imitate 15 aquatic animals (that we know of), including sea snakes, lion fish, flatfish, giant crabs, stingrays, and jellyfish. It can even do giant seashells, because why should it limit itself to just animals?
There are mimics that it can do that we haven’t figured out what it’s trying to mimic. Robert Krulwich of NPR wonders if maybe it’s unknown mimics are a product of its imagination.

Octopi are so intelligent, it wouldn’t surprise me at all if they possess imagination. I love how Mr. Krulwich describes this creature as the Meryl Streep of the ocean.

I bet if the mimic octopus saw a picture of Meryl, it would instantly try to transform into her.

…Or what if Meryl Streep is a mimic octopus in disguise?!
The hair in this photo does look suspiciously like octopus arms. It would also explain her ability to morph into any role with apparent ease. It would make sense that the greatest living film actress is an octopus.
No human could be that awesome.

I’m on to you, Meryl!