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Submission + - Octopuses Can Rewire Their 'Brains' By Editing Their Own RNA On the Fly (sciencealert.com)

An anonymous reader writes: Octopuses have found an incredible way to protect the more delicate features of their nervous system against radically changing temperatures. When conditions fluctuate, they can rapidly recode key proteins in their nerve cells, ensuring critical neurological activities remain functional when temperatures drop dramatically. How do they do it? By deploying a rare superpower – editing their RNA on the fly, an ability found in some species of octopuses, squids and cuttlefish. It's an unusual strategy, but it appears to be an effective one, and scientists believe that it may be widely adopted throughout the world of cephalopods. [...]

Their subjects were California two-spot octopuses (Octopus bimaculoides), whose entire genome was first sequenced in 2005, making it a useful animal for understanding genetic changes. The researchers acclimated these octopuses to warm water at 22 degrees Celsius (71.6 Fahrenheit) or much chillier water at 13 degrees Celsius (55.4 Fahrenheit), then compared their genetic information against the database genome. They specifically looked at over 60,000 known editing sites, and what they found was astonishing. "Temperature-sensitive editing occurred at about one third of our sites – over 20,000 individual places – so this is not something that happens here or there; this is a global phenomenon," says physicist Eli Eisenberg of Tel-Aviv University, co-senior author of the paper. "But that being said, it does not happen equally: proteins that are edited tend to be neural proteins, and almost all sites that are temperature sensitive are more highly edited in the cold."

So the editing seemed to be in response to acclimating to cold, rather than warm water, affecting neural proteins that, specifically, are sensitive to cold temperatures. And tests of structural proteins critical for the function of the octopus nervous system – kinesin and synaptotagmin – found that the changes wrought would have an impact on their function. It was possible that what the team observed was the result of being in a lab, so they caught wild California two-spot octopuses and Verrill's two-spot octopuses (Octopus bimaculatus) in Summer and Winter and checked their genomes, too. These octopuses had similar patterns of RNA editing that suggested they were optimizing their function for the current temperature conditions.

The team also tested to see how quickly the changes take place. They tweaked the temperature of an octopus's tank from 14 degrees Celsius to 24 degrees Celsius or vice versa, tuning the temperature up or down by 0.5 degrees increments over the course of 20 hours. They tested the extent of RNA editing in each octopus just before starting the temperature change, just after, and four days later. It happens very quickly, the researchers found. "We had no real idea how quickly this can occur: whether it takes weeks or hours," explains [marine biologist Matthew Birk of the Marine Biological Laboratory and Saint Francis University]. "We could see significant changes in less than a day, and within four days, they were at the new steady-state levels that you find them in after a month."

Emulation (Games)

Submission + - JavaScript Gameboy emulator, detailed in 8 parts (imrannazar.com)

Two9A writes: JavaScript has shed its image of being a limited language, tied to DOM manipulation in a browser; in recent years, new engines and frameworks have given JS a reputation as a language capable of bigger things. Mix this in with the new elements of HTML 5, and you have the capacity to emulate a game console or other system, with full graphical output. This series of articles looks in detail at how an emulator is written in JavaScript, using the example of the Gameboy handheld: starting at the CPU, and (as of part 8) running a copy of Tetris.

Comment Re:C++? (Score 1) 546

Let's ignore that C doesn't even have "pass by reference"; there's either pass by value or pass by pointer-to-a-value, which is itself a value.

I never understood the animosity against C++. Sure, it's a larger language (you just need to look at the difference in sizes between K&R and Stroustrup to see that); and sure, g++ spits out utterly incomprehensible errors when you work with the Template Black Magic; but on the whole, I find it makes for a more structured program than the equivalent C.

Of course, the only way to fly is Brainfuck; don't let anyone tell you otherwise.

Comment Re:BTDT (Score 1) 582

That sounds very similar to what I did back in 2006, on the Nintendo DS. I tried to put together the smallest DS ROM that could actually do something (in this case, turn the screen red):

http://imrannazar.com/The-Smallest-NDS-File

I ended up embedding the code in the NDS header, which is 352 bytes long; I don't think it's possible to get a DS ROM smaller than that, but I'd be willing to be proved wrong.

Idle

Submission + - "Dead" Facebook User Gets Better (thulbourn.com)

Two9A writes: With the recent introduction of memorial accounts on Facebook, the potential arises for hilarity and abuse. Simon Thulbourn's Facebook page has been marked as "in memorial", on the word of a report submitted by one of his friends; unfortunately, the closest the report gets to Simon is that the funeral service in question was officiated by "Revd Simon Thorburn", which seems to be enough for Facebook to mark an unrelated user's profile as dead. Questions have previously been raised about the standard of proof required by Facebook for this service; it seems that those questions were pertinent, if the lax attention paid to these reports by Facebook staff continues.

Comment Re:Vaporware (Score 1) 1006

Your figures are very interesting, but bad.

You state that a million electric vehicles, charging all at the same time, will take 3TW of power for an hour. When was the last time you saw a million cars fuelling up at once?

If we assume that the car charging times are evenly distributed, and that the cars all need fully recharging once a day, we get 0.125TW of power for each hour of the day. That's worst case, with the stipulations I've just given; a long-range EV isn't going to need charging once a day, unless it's constantly going transcontinental. With 1.08TW of capacity, I don't think we'll have a problem.

Comment Re:Oblig xkcd reference (Score 1) 198

Of course, this neglects to mention the sterling work that members of the xkcd forums do to destroy and/or improve the comics, in the spirit of "Making xkcd Slightly Worse".

I'm currently building an archive of the xkcd/sw posts, and I'm looking to release a book of the "best" of the worsened comics. I will probably be buying Randall's book, if only to get ideas for layout and styling.

Comment Re:They missed the Apple ][ (6502) 16 bit index (Score 2, Informative) 731

I had a similar problem when I was writing an "extended text-mode" (80x25) software driver for the C64, recently. Since each character is encoded into 8 bytes, and there are 256 possible characters, the character definitions span over a wider space than the 8-bit index register can fetch.

Simple to fix: just self-modify the instructions that handle the font buffer, changing the base pointer as you enter a new page. Since the C64 has a 6510 chip, you'll probably understand the code quite well.

I wrote an article on the code a few months back, might be an interesting read.

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