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A Worm's Mind In a Lego Body

teslar Re:No programming? (200 comments)

The behavior emerged through evolution and was encoded in the neurons by nature

What has been implemented in this robot has nothing to do with biological neurons of C. elegans.

The robot uses integrate-and-fire neurons. The "signal" sent from pre- to postsynaptic neuron is an integer equal to the number of connection between the neurons in the real worm. If the sum of input exceeds a threshold, the neuron "fires" (sidenote: right here's a bit of programming: how did the threshold values get chosen?).

C. elegans neurons do not "fire" (they are not spiking neurons and lack Na+ channels) but use calcium-based analog signals.

The body does matter too. C elegans has muscles on either side that it contracts alternately to move in a sinusoidal fashion. Not wheels. C elegans locomotion does not work like wheeled locomotion.

So, yes, you are right, C elegans neurons encode behaviour appropriate for a C elegans body given the biology of the neurons available here. None of this, however, makes it into this robot. An abstraction of the connectome does (C elegans has both electrical and chemical synapses; that distinction seems to be lost here too) and that's it.

It is kinda cool that the connectome does seem to naturally implement some basic response patterns; but given that muscles have been replaced by wheels, I'm not sure how meaningful that actually is.

about 2 months ago

First Movie of an Entire Brain's Neuronal Activity

teslar Re:Mapping the Nematode? (44 comments)

Could a complete mapping of the neural network be accomplished?

The C elegans brain has been completely mapped in terms of connectivity a long time ago. See for instance:

Would it be possible to artificially trigger a neuron to verify the mapping?

Interesting thought - I'm not aware of anyone having done that but it's been a while since I followed the C elegans literature closely.

C elegans is pressurised, so you can't easily stick an electrode (assuming you had one small enough) next to your neuron of choice to stimulate it. Maybe you could make a secific neuron become light-sensistive and use optical stimulation (the worm's transparent, so that helps) but again, not sure anyone has ever attempted that in C elegans.

The converse has been done repeatedly though: either ablate a neuron using a laser or design a mutant that won't have it in the first place (remember that the C elegans genome is completely mapped too) and see how it affects behaviour.

about 7 months ago

Lucasfilm Announces Break With Star Wars Expanded Universe

teslar I have a much neater solution. (157 comments)

Someone from the future travels to the past, changes something fundamental and the universe slips into an alternate reality from which it can never return and in which no event can be expected to unfold as it did in the original.

Not only will this by definition never be inconsistent with the EU, it will give the writers ways of amusingly rehashing old stories by subtly altering some key elements things, like who gets to die of radiation while saving the crew. Maybe, in Episode VII, Luke will hack off Vader's hand?


about 9 months ago

Mathematical Proof That the Cosmos Could Have Formed Spontaneously From Nothing

teslar Re:Not possible (612 comments)

Physics is not accessible to mathematics

This is very much still an active topic of discussion, actually, and certainly not as settled or clear-cut as you seem to think. You can start with Wigner's essay.

And just to provide the opposite viewpoint to yours, some people will of course argue that physical reality is mathematical.

about 9 months ago

Scientists/Actress Say They Were 'Tricked' Into Geocentric Universe Movie

teslar Re:Actually... (642 comments)

It's an ill-posed question since to say that something is at the center of everything requires some sort of absolute position system (a la Aristotle), which is a meaningless concept (an insight that goes at least as far back as Galileo).

about 10 months ago

Replicant OS Developers Find Backdoor In Samsung Galaxy Devices

teslar Re:OTA updates (126 comments)

I'm curious what functionality is affected, if any is, by rejecting any of these IPC_RFS_ I/O.

Remotely wiping a stolen mobile phone perhaps? It's just a guess - but by definition that would require the ability to do stuff to the phone's file system without the current user's knowledge or permission.

about 10 months ago

Facebook Mocks 'Infection' Study, Predicts Princeton's Demise

teslar Re:Obligatory XKCD (193 comments)

Better xkcd - at least this also uses data collected from Google.

1 year,2 days

Voynich Manuscript May Have Originated In the New World

teslar Re:I deciphered it last month. (170 comments)

I'm certain that "words" in the manuscript do not represent words in the original language. They are merely chunks of ciphered text, which explains the unusually homogeneous word lengths, for one thing. I believe the length of the ciphered words is thus arbitrary and chosen by the person doing the ciphering. That also explains how word length and spacing can be perfectly justified and fit along the varied shape of images

Now that you mention it... it's obviously an early entry to the IOCCC.

1 year,4 days

Elsevier Going After Authors Sharing Their Own Papers

teslar Re: wait (259 comments)

It isn't clear here whether the papers in question were the pre- or post-editing versions

They are going after the final, published versions (including Elsevier formatting and all), commercial use of accepted manuscripts, systematic distribution and the like (some of which applies to academia.edu). In other words, what you said was fair game still is - you are allowed to share the accepted manuscript with others (including on your website where Google Scholar will pick it up and render it discoverable in a matter of days, so it's not like this restricts you), you (or anyone else) just can't make money off it and you can't use their typesetting.

For the accepted manuscript version, let me just quote from Elsevier's author rights:

Elsevier believes that individual authors should be able to distribute their AAMs for their personal voluntary needs and interests, e.g. posting to their websites or their institutionâ(TM)s repository, e-mailing to colleagues. However, our policies differ regarding the systematic aggregation or distribution of AAMs to ensure the sustainability of the journals to which AAMs are submitted. Therefore, deposit in, or posting to, subject-oriented or centralized repositories (such as PubMed Central), or institutional repositories with systematic posting mandates is permitted only under specific agreements between Elsevier and the repository, agency or institution, and only consistent with the publisherâ(TM)s policies concerning such repositories. Voluntary posting of AAMs in the arXiv subject repository is permitted.

So you can see how academia.edu falls foul of this while your right to share your work does not.

(Some of my papers are published in Elsevier journals - they are however also all open access. In case you're wondering.)

about a year ago

How long before most automobile driving is done by computers?

teslar Re: Never gonna happen. (472 comments)

Having the automated car set up in a manner that it won't drive into situations it gauges to be high risk, and it offers control to the driver or pulls over to the next safe location and stops isn't hard.

Hi, some of my research is in human/car interaction and work closely with people who spend a lot of time thinking about just the problem you dismiss as not hard. It is incredibly hard. Imagine you have an unforeseen emergency (only considering foreseeable risks and avoiding them like you seemed to imply isn't very useful) arising from a complex situation and, let's be generous, 10 seconds before everyone dies to hand control back to the human who, at this moment is maybe asleep or reading the newspaper while sipping his tea. He has no clue at this point what is going on. How exactly do you not only get him in control but make sure he has the complete overview of the situation, including where and what the danger is exactly, so that he can react appropriately in the time remaining? Until there is an answer to that, until we can be sure that a human can always retake control if needed, no matter what, automated vehicles are going nowhere. And if that means the driver will continue to have to pay attention throughout, then so be it. And this is why handing control back to the driver is one of the really big research areas in automated vehicles right now.

about a year ago

How long before most automobile driving is done by computers?

teslar Re: Never gonna happen. (472 comments)

Your brain is a computer.

Fun fact: computers were human long before they were machines.

about a year ago

Should the Next 'Doctor Who' Be a Woman?

teslar Re:and how do you resolve the paradox (772 comments)

Unless you are going to make the time lords all capable of changing sex

Meet the Corsair Also, Romana was at least once capable of choosing what she would regenerate into (though I don't think that got mentioned again since) - so I guess that if the Doctor wanted to regenerate as a woman, he could.

about a year and a half ago

Matt Smith Leaves "Doctor Who"

teslar Re:No way (375 comments)

we know (unless they changed it since he's the last timelord), timelords only get 12 regens (making 13 total lives)

Not anymore, the Doctor has had infinitely many regenerations for a while now.

about a year and a half ago

Facebook "Trusted Contacts" Lets You Pester Friends To Recover Account Access

teslar Re:Security (114 comments)

I suppose the one worry is that if someone has the ability to impersonate your e-mail and has access to your friends list, he could then impersonate you and ask *all* your friends for codes. The attacker doesn't need to know who the trusted friends are since your circle of friends would not easily be able to detect that everyone's been contacted. The attacker may mine the publicly available info on the friends to personalise the message a bit, if not, keep it short and very simple. It's not like this request would come in a long personal message anyway. It IS likely that it will come by e-mail though since you'll already be at the computer, trusted friends may be around the globe and so on. In short, you need your friends to be capable of detecting an impersonation attempt, even if brief and potentially conveying a sense of urgency. Remember, your trusted friends may be the same people who click on links that appear to be from you *because* they trust you. So in summary, while I do think this is pretty neat, I also wonder if this is not rather vulnerable to social engineering (perhaps not so much among the /. crowd - but generally)?

about a year and a half ago

How often do friends/family call you for tech support?

teslar Never (255 comments)

It used to be all the time. I was running windows and so was everyone else. I eventually switched completely to Linux (and started using the "I don't use windows anymore, no clue"... excuse) but that didn't stop the tech support calls.

Moving the family to OSX however did. That was 3 years ago and there has not been a single tech support issue since then.

about a year and a half ago

Sexism In Science

teslar Additional conditions (467 comments)

Not to disagree with anything in the paper and certainly not with the message, but personally, I would definitely have wanted to see at least one more condition: same resumes with no names at all. That should give nice baseline against which to compare both conditions (e.g. are female salaries marked down or are male salaries marked up).

Also, I wonder what would happen if one were to replace the names with simply an indication of gender (male/female). Unlike the neutral condition, I don't think this would improve the study... I'm just curious if the gender is enough or if there's something specific about reading male vs female names.

more than 2 years ago

Data Breach Reveals 100k IEEE.org Members' Plaintext Passwords

teslar Re:For God's Sake (160 comments)

I'm a scientist. I write papers that are published in academic journals and I review such papers for journals. Journals use editorial managers to, well, manage, the entire process and you'd be surprised how often those send out automated e-mails that, helpfully, contain my login and password IN PLAINTEXT, just in case I might have forgotten (even if I did not request the password).

In general terms, if you use a website that is able to remind you of your password if you forgot, consider that password known to the world and all other accounts that use the same or a similar password at high risk of being compromised.

Oh and I have an Obligatory XKCD too.

more than 2 years ago

If I could print 1 replacement organ ...

teslar Re:Comments in here are one of three categories (544 comments)

I see your 1 and 1b and raise you:

1c Heart: to be implanted alongside my existing one so I can go to Dr Who conventions and freak the crap out of them (alt: get laid by the Amy / Rose lookalikes).

(and for other the /. angle: I do wonder what hooking up a second heart would actually do to a human - assuming it was hooked up correctly (for whatever definition of "correctly" makes sense here) and space wasn't an issue.)

more than 2 years ago



Selling used software licenses legal in Europe, even if downloaded

teslar teslar writes  |  more than 2 years ago

teslar (706653) writes "The Court of justice of the European Union has ruled that An author of software cannot oppose the resale of his "used" licences allowing the use of his programs downloaded from the internet (PDF). This follows a legal battle between German company UsedSoft (which does just that) and Oracle. From the press release: "By its judgment delivered today, the Court explains that the principle of exhaustion of the distribution right applies not only where the copyright holder markets copies of his software on a material medium (CD-ROM or DVD) but also where he distributes them by means of downloads from his website" (the principle of exhaustion of the distribution right means that "A rightholder who has marketed a copy in the territory of a Member State of the EU loses the right to rely on his monopoly of exploitation in order to oppose the resale of that copy")."

teslar teslar writes  |  more than 7 years ago

teslar (706653) writes "Researchers at the Computational Neuroscience Group of the UPF in Barcelona have analysed a year's worth of Slashdot activity. Their results (PDF): Both the distribution of comments per post and the distribution of individual people's comments on posts can be fitted by a lognormal distribution and can thus be described by only two parameters. Daily and weekly activity cycles are also observed, revealing an American-centric usage of the site and a user who seems to almost exclusively visit Slashdot during his working hours ;)"


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