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Comment Another good stream here (Score 5, Informative) 933


Major media helicopters have been forced out of the air by NYPD. Lots of fresh news on twitter:

NYPD Police scanner here:

NYPD switchboard isn't taking any more calls:

Comment Why phase-change materials are useful (Score 2) 74

This is the worst /. article *summary* that I've read this week. TFA addresses phase-change materials (PCM)-based memory only. This is the self-same stuff used in writable DVDs, and has some very cool properties. In the above summary, "Faster than other solutions currently available" refers specifically to PCM-based memory. The durability of PCM memory is one big plus -- all those sci-fi plot twists from cosmic ray induced bit-flips in charge-dependent memory? Yeah, not a problem here.

TFA itself is a really neat little paper. It's in Science, which indicates that some reviewers somewhere thought it both important and well-done. It's surprisingly readable, too, which is a little unusual for these sorts of papers. These folks were clearly thinking about Fab-type high volume / high yield questions. For example, the "quality" of the carbon nanotubes (CNTs) isn't important. They're just an easily-broken conductor. Clearly this isn't ready for prime-time, but they didn't just make 1 device, test it, and publish. They made at least 100, while varying conditions.

From TFA's Supporting Online Material:
" In order to create the CNT nanogaps, we performed electrical breakdown of CNTs both in ambient air and under Ar flow. We have also cut CNTs with AFM manipulation, but the elec- trical breakdowns offered a much faster route to obtain a wide range of nanogaps (Fig. 4). Of course, while the CNT breakdown method is extremely useful here, it would not be the preferred route for obtaining nanogaps in a more scalable manufacturing environment. Nevertheless, we believe it is useful to present some observations associated with this technique here.

First, we note that CNT breakdowns under Ar flow were done by flowing Ar (which is heavier than air) from a small nozzle over the entire test chip while probing. Thus, some dimi- nished amount of oxygen was still available for CNT breakdown, unlike the breakdowns per- formed in vacuum in the second panel of Fig. 2C of Ref. (1). There, the CNT break in vacuum could lead to SiO2 damage, which was not seen here either in ambient air or under Ar flow.

Second, we found that nanogaps formed in Ar are always smaller (always
We report additional statistics for all devices measured by AFM in Fig. S7. We find no clear dependence between nanogap size and CNT diameter (Fig. S7A). In a sense, this is encouraging because it suggests that tight control of CNT electrode diameter may not be necessary to make very low power devices. Our simulations (Figs. S3 and S4) also suggest this is the case, because the resistance of the GST bit always dominates that of the CNT (both in the a- and c-GST phase), thus rendering variability in the CNT of less importance. This fact could be important for mass production of such electronics where some amount of CNT variability could be tolerated."

Comment Re:What ever happened to VR? (Score 1) 164

It really does seem that the goggles just aren't there, which is probably a function of (lack of) demand, which in turn is a function of (lack of decent) goggles. It all goes back in part to the killer app question.

For the last 5-odd years, a pair of 240*320 res goggles have been available at the mall, ala Sharper Image and its ilk. For ~$500. Now you can buy a ginormous HD flatscreen TV or 2 nice monitors for the same price. Which would you prefer? Given lack of demand for said goggles, they stay expensive and crappy.

With 3D coming into play in hardware and ultimately game design, I hope there will be more impetus for hardware manufacturers to get onboard. Flatscreen prices didn't really tumble until a year or 2 into mass-market, when yields really got good at the fabs and volumes got high. Stereo microdisplays at HD? Sounds expensive at current fabs.

Form-factor is another unanswered question. The active 3D TV glasses look stupid, and aren't very comfortable. I wear glasses, and hate the whole "glasses on glasses" thing. If the 3D TV folks can figure this out, maybe the form factor can follow for goggles. For example, should goggles block out all ambient light? That plus bluetooth headsets sounds like the true beginning of the zombie apocalypse!

Comment Re:Figures (Score 1) 126

Now if only the doctors get on the bandwagon and start diagnosing people based on an individuals genome.

Sorry, that'll take 10+ years of basic research, 10+ years of clinical trials to provide practical applications for findings of said research, plus another 10+ years for a new generation of doctors to matriculate with knowledge of said applications. More likely, big pharma will be "farming" human genome data for drugs with rapid development platforms. The scary part here is that, without basic research, more unintended consequences are to be expected...

Comment Re:monopolies (Score 1) 722

The only thing it has going for it is chic-factor, name-recognition and the app store.

And safari? What other mp3 player can I check my email, wikipedia, and google on? Please, I'm curious. I'd happily use a ~$200 android device as my primary media player and pocket (contract-free, WiFi) internet portal.
I'm moderately anti-apple (and *very* anti-itunes). As much as I hate to say it, I've yet to see anything that comes marginally close to the Ipod in cost, convenience, and overall versatility. And no, an Adam Ink won't fit in my pocket.

Comment Re:Right (Score 1) 298

More from TFA

"From 1.0MHz to 3.0GHz, its effectiveness in attenuating RF signals was found to vary from 40dB to 73dB across the entire range of frequencies (Figure 1). Theoretically, an enclosure made of this material would reduce signal intensity by a factor of 104 to 107.3, blocking essentially all ambient RF energy, including the naturally occurring RF background."
"In both the mock-Faraday cage and the uncaged area, numerous stations were received in the AM and FM bands. A sweep of RF background at the site, June 6, 2009, using an Anritsu spectrum analyzer, showed that field intensity ranged from 117dBm to 87dBm at frequencies from 1 to 1,000MHz. Mean field intensity was 109dBm. "

She definitely did her homework.

As a society, we spent the 20th century establishing that the *energy* in various sources of radiation like lasers, microwave ovens, radioactive decay, etc. etc. can damage and kill living organisms. Yet much work remains to exactly how the information encoded within radiation effects and is processed by organisms.

Imagine living the first 5 years of your life awash in a constant 60-70 decible wash of white noise. It wouldn't cause organic "damage" by harming your ears, but it's not hard to see how it could hinder, say, language acquisition...

Comment Why the gulf stream goes North - Salinity Gradient (Score 5, Informative) 568

True, ocean currents will still move. They're definitely chaotic system and often behave "counterintuitively".

But all that warm water goes so far north largely because of (cold) water with high salinity. This water is dense and sinks. This is called North Atlantic Deep Water formation, and possibly drives deep ocean currents around the world.

This salinity gradient is the key energy source that "pulls" warm water so far north, more than the thermal or momentum gradients.

This gradient broke down during "the Younger Dryas cold episode, which chilled the North Atlantic region from 11,000 to 10,000 yr BP." "[This] is postulated to be a turnoff [...] of the North Atlantic's conveyor-belt circulation system which currently supplies an enormous amount of heat to the atmosphere over the North Atlantic region. This turnoff is attributed to a reduction in surface-water salinity, and hence also in density, of the waters in the region where North Atlantic Deep Water (NADW) now forms." Paleoclimate claims are supported by oxygen and carbon isotope studies on plankton.

see http://www.nature.com/nature/journal/v341/n6240/ab s/341318a0.html

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