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Comment Some questions about gene expression (Score 1) 34

Heyo -- thanks for the heads-up on Twitter. I'm the sysadmin at a small university department, and I work with scientsts studying gene expression. They're good and patient people, but sometimes I feel a bit like I'm questioning the foundations of their work...which feels either rude or ignorant.

First off, I'd always been under the impression that DNA was only/mainly used during reproduction -- a cell divides under DNA direction, some bit of the cell is the machinery that makes whatever protein is needed during its life, and DNA isn't involved much after that. However, I'm starting to understand (I think...) that I've got it all wrong. My understanding now that gene expression can basically turn on a dime, and that *this* is the usual way a cell makes a protein: something happens to a cell, it says "Whoah, I need protein X", and it starts transcribing the DNA so it can manufacture it (modulo things like gene regulation). This process can take very little time (hours or less). Have I got that right?

Second: one of the things they study is datasets of gene expression in post-mortem brains. (Well, technically I guess I've got that wrong, since genes aren't expressed post-mortem... :-) As I understand it, someone dies -- say, someone with schizophrenia -- their brains are donated to science, and at some point someone does microarray sequencing of blendered neurons. This is compared to brains of control subjects, gene X is found to be over/under-expressed in schizophrenic brains, and so gene X is involved somehow in schizophrenia. (This is a gross simplification, especially in the case of schizophrenia; my understanding is that these signatures cover many, many genes, they're subtle at best, and there's nothing like "a gene for schizophrenia".)

What I don't understand:

a) Since time passes between death and sequencing, how much fidelity does/can this have do what was going on at the point of death?

b) Even if it is a good indication of what was going on at death, how does that relate to a long-term illness like schizophrenia when (assuming I've got this bit right) gene expression can turn on and off in a very short time? I realize there are (ahem) ethical problems with doing brain biopsies on living subjects, and that post-mortem is the best that can be done -- but how good can it be?

Many, many thanks for your time. Any questions about system administration, let me know. :-)

Comment Sorry, what? (Score 1) 334

  1. What's their methodology? How exactly did they get this info? I see nothing here like a link to a full paper.
  2. Who are they and why should I trust them? Disclaimer: I could turn out to be woefully ignorant, and maybe I should just get my head out of my ass. But their main web page appears to be amazingly content-free, and there are two posts on the blog -- this is one of them. (To be fair, the
  3. They only present two data points here -- Jan 18 and Jan 19. What's happened since? Why the breathless summary (Slashdot's and the blog post) saying file sharing is all going to Europe now?
  4. The post-Jan 19 diagram says the hosting provider breakdown changed, which is presumably why they're breathless about Europe. But there's no data presented on where those new providers are located -- no corporate info, no datacentre locations, nothing.

If there's something to see here, I'm missing it.

Comment Radia Perlman's Ephemerizer (Score 2) 209

I think that what you want is The Ephemerizer, by Radia Perlman (she of OSPF fame). I heard about this a few years ago at the LISA conference, and a bit of digging turned it up. From the abstract:

This paper is about how to keep data for a finite time, and then make it unrecoverable after that. It is difficult to ensure that data is completely destroyed. To be available before expiration it is desirable to create backup copies. Then absolute deletion becomes difficult, because even after explicitly deleting it, copies might remain on backup media, or in swap space, or be forensically recoverable. The obvious solution is to store the data encrypted, and then delete the key after expiration.

Google turns up this copy in PDF.

Hope that helps!

Comment Safety deposit box (Score 1) 402

You could try something like:

  • Keep a list of passwords (I use Emacs + GPG, but there's bound to be something out there that'll work for you if that's not your style)
  • Print out the list monthly (if that really is how often you change passwords)
  • Seal it and put it in a safety deposit box at your local bank
  • Tell everyone "In case of my death, go here for passwords"

(Alternately, this could be something a lawyer could help with -- something like holding passwords in trust, only to be given up in the event of X, Y, Z...)

Yes, it's a pain in the ass. But it would work, and it would mean your executor/spouse/etc would only have one set of people to convince that you're dead.

Comment That's it. (Score 5, Interesting) 658

I'm a Canadian sysadmin. I love -- LOVE -- the LISA conference (http://www.usenix.org/lisa11/). It's wonderful, informative, and fun; I've made great friends there, learned an incredible amount and generally enjoyed myself enormously.

Last year was the third time I went. The conference was in San Jose. I took a bus and a train -- which took over 24 hours -- from Vancouver to San Jose, rather than fly and go through a naked body scanner. I figured if I'm going to talk the talk, I should walk the walk.

I'd already decided to skip this year's conference; it's in Boston, which is a long way to go by train or bus. I didn't want to be away from my family for that long. But I had been thinking about going next year, when it's going to be in San Diego.

I'm not going now. Not if this crap keeps up. I'll watch the video on my workstation, I'll listen to the MP3s on the bus, and I'll stay here in Canada. We have problems of our own -- but random searches and "papers, please" for the crime of taking the goddamned train are not one of them.

I'll miss y'all.

Submission + - Samsung plants keyloggers on laptops it makes (networkworld.com)

Saint Aardvark writes: "Mohammed Hassan writes in Network World that he found a keylogger program installed on his brand-new laptop — not once, but twice. After initial denials, Samsung has admitted they did this, saying it was to "monitor the performance of the machine and to find out how it is being used." As Hassan says, "In other words, Samsung wanted to gather usage data without obtaining consent from laptop owners." Three PR officers from Samsung have so far refused comment."

Comment The FSF got it right (Score 5, Insightful) 259

Still, I can't help but think: digital rights management, sure! Where are my rights, as a consumer, and who is managing them?"

And that is why the Free Software Foundation insists on calling this technology "Digital Restrictions Management (http://www.defectivebydesign.org/what_is_drm): it points out that this is meant to keep YOU, the paying customer, from doing useful things with the stuff you buy.

Transportation

Electronics In Flight — Danger Or Distraction? 532

another similar writes "IEEE Spectrum has a blog post revisiting the debate on whether electronic devices pose a risk to flight avionics spurred by a NY Post article about Arianna Huffington's refusal to power down her Blackberry during takeoff. The post points out the EU's removal of their own ban on cell phone use in 2007 and the likelihood of significant non-compliance daily in the US — and curiously, planes haven't been falling from the sky at a similar rate. While the potential exists for there to be a problem, it would appear the risk is low. Ever bent the rules? Is an app for landing commercial jets somewhere in our future?"
Technology

Using Technology To Enforce Good Behavior 249

Ismellpoop writes "With the new year upon us and resolutions being made to change unwanted behavior, many tools are now available to help people stay in line, such as a GPS-enabled app that locks down texting once a car gets rolling and a program that cuts off credit-card spending. Another device monitors your workout and offers real-time voice feedback. Have we entered an era in which electronics serve as mother, cop and coach because we can't manage our own desires?"
Sci-Fi

Stargate Universe Cancelled 762

Torino writes "SGU has finally been cancelled, with the remaining 10 episodes to air in Spring. Apparently, the cast wasn't told ahead of time, and some of them learned of the cancellation via Twitter. SGU has had its share of problems, even spawning a community of people who dislike the show. Can it be saved via fan support, given the steadily declining viewership numbers? Do you think the show had the potential to improve?"
The Internet

Web Bugs the New Norm For Businesses? 108

An anonymous reader writes "What ever happened to the good old days, when underhanded email practices were only used by shady email marketing companies and spammers? Today, it seems, the mainstream corporate world has begun to employ the same tactics as spammers to track their customers' email. Jonathan Zdziarski noted in a blog entry that AT&T is using web bugs to track email sent to customers. Could this be used for nefarious purposes?"

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