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Comment Re: Duh (Score 1) 462

The number of cases of measles in total might have been severely underreported, but deaths and hospitalizations? It's one thing if the parents keep home a kid sick with measles but not seriously ill and don't bother to file an official report. But if the kid dies, surely the coroner is most likely going to find out what killed him, and if he's taken to the hospital, the hospital staff will diagnose him and record it in the hospital records.

This was before ICD coding, among other things. If the proximate cause of death was pneumonia, then there was an excellent chance that the attending doc would have written it off to "pneumonia" rather than "measles" or "measles pneumonia." Things changed when measles became rarer and the reporting requirement had more teeth (IIRC, my parents knew that there was nothing the family doc could do for measles so when I got it they never even took me to him.)

Then there's the less-common sequelae such as subacute sclerosing panencephalitis. Likely not reported at all, thanks to the time delay. Similarly for the more common forms of encephalitis -- death by encephalitis was much more common for a lot of reasons and measles was just one of them.

Comment Re:The really sad thing is vaccines improving (Score 1) 462

There are no childhood vaccines that are not available without thimerosol, including the MMR vaccines that are the subject of this article.

And for full appreciation of the massive fail that the "EEP!!! thimerosol in MMR!" position represents: not only has thimerosol been removed from childhood vaccines in the USA, but (pay attention now) MMR never had thimerosol in the first place!

Comment Re:Duh (Score 3, Informative) 462

How does a baby get Hepatitis B?

From other babies. Those of us who've had them know from experience that "bodily fluids" get exchanged in lots of ways that don't involve sex or needles.

A friend's father (60-something) has chronic HepB, undoubtedly from a childhood infection. Fortunately, she doesn't -- but his liver is mostly gone, to the extent that she was considering donating a lobe of hers.

Comment Re: Duh (Score 1) 462

With effective modern medical care, the death rate from measles is about 0.1%. If proper care is not given, it can be as high as 10%

Mostly from pneumonia. The mortality from measles dropped pretty dramatically in the 30s with oxygen and other supportive treatment for pneumonia, and again in the 40s with antibiotics. I have a copy of a medical text from the 30s that cites the 10% number, BTW. There's a reason my mother was terrified when I got measles in the 50s.

Just prior to the introduction of the measles vaccine in the USA, approximately 450 people died each year of the disease, and 48,000 had complications severe enough to require hospitalization.

That's the reported number; there's good reason to suspect that the actual numbers were much higher. The reported incidence was less than 10% of the age cohort, and we know that (thanks to measles being extremely contagious) that the actual incidence was close to 100%.

Comment Whiskers (Score 1) 126

It's even worse than that. Tin whiskers - it's a characteristic of the metal. No one knows why, the only suspicion we have is Tin does it to relieve stress in the crystal.

Fullerenes aren't crystals, though. For the same reason that graphene and nanotubes don't have carbon wandering around all over the place, neither is tin likely to. In fact, given the higher mass of a tin atom compared to carbon, it could be a whole lot harder to get one to leave its place in the array.

Comment Doubtful (Score 2) 126

Whiskering is a phenomenon of crystalline metals under strain. This stuff isn't crystalline, and it's not really metallic in the usual sense. Fullerenes are strange things indeed, but if tin atoms are wandering around then the stuff would be too unstable to use for most things anyway.

Comment Re:It's all simulations! (Score 1) 126

Other questions:

1. If a sheet of 1 atom thickness can transport x A/m at no loss, (ampere per meter of sheet), then how close can you stack these sheets together before x becomes significantly less?

And the related question of whether the change is dramatic enough that it can be used for active devices. Hmmmm ...

Note that this is much less of an issue for power distribution on-chip because stacking layers can dramatically reduce field strength by coupling currents in opposite directions (and incidentally create bypass capacitance, of which there is never enough.)

2. If there is a (mutual) magnetic interference between two layers that destroys the superconducting effect, then will the superconductor actually work when immersed in an external magnetic field?

Unless the critical field is really low, which seems unlikely at room temperature, this isn't going to be a problem for anyone not building MRIs or particle accelerators.

Comment Re:It's all simulations! (Score 5, Informative) 126

What is the maximum current that can be transported through strips of various widths?

Mostly moot. The really nasty consequence of conductive losses in semiconductors is that it degrades signals traveling across the chip. We insert buffers along the route to restore signal amplitude and reduce delays (those RC delays are ugly). This would zero the resistance and reduce the capacitance, which is a big deal. Also, for reliability reasons, we'd probably build laminates with multiple layers separated by dielectrics.

How sensitive to defects is the process?

Depends on the width of the path. The usual solution is to add redundancy, multiple single-atom layers separated by dielectric. Vertical space on chips is relatively cheap, as long as you don't need to use extra mask layers or move the material from one process stage to another.

Tin is going to be a major problem for much semiconductor processing - as it means you basically now can't solder the chip, or do any even 'low' temperature processing after it's deposited - it has to be the last layer.

We don't solder the devices directly anyway -- the organic dielectrics used in advanced processes like the old metal-melting temperatures even less than tin does.

Comment Single layer (Score 5, Informative) 126

For those of you not in the semiconductor business, the fact that these conductive strips is pretty important too. Most of the capacitance (that has to be charged and discharged whenever a node switches, causing losses in the transistors driving the node) is sidewall capacitance: capacitance between adjacent lines on the same level. Single-layer conductors won't completely do away with lateral capacitance (fringing, for instance) and the vertical capacitance will still be there -- but there's going to be a big reduction in power if they can get this to work. My guess is that by the time it reaches production it won't exactly be one layer, either -- it'll be a laminate with multiple redundant layers.

Always assuming the predictions play out.

Comment Re:Governor Appointed (Score 1, Interesting) 640

So you're saying nobody anywhere ever, other than the government, would fund climate research? That just makes no sense at all.

Not only that, but there are glaring counterexamples. Koch money, for instance, funded BEST.

All sorts of comments possible on that one, but I'll leave them for another day.

Comment Rightly so (Score 1) 437

One thing I've noticed as a passenger is that the most dangerous-feeling aspect of flying right now seems to be the winding security line itself.

Hardly surprising. Thousands of people packed tighter than they will be on board, all it would take is one suicide bomber (you know how much explosive and shrapnel can be packed into a roller bag? Never mind nerve gas.) to wipe out more people than have died in the USA to air travel since commercial flight began.

But don't worry. If it ever happens, TSA will adopt new procedures that will have people go through a security examination checkpoint before getting into the security line.

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