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Comment: Re:Legitimate use for 3D printing (Score 1) 58

by smellsofbikes (#49147919) Attached to: Researchers Create World's First 3D-Printed Jet Engines

Jet engines are an awful candidate. The tolerances and material requirements to not tear themselves apart are tremendous. We're talking about turbine blades spinning at 5k-45k RPM, at temperatures of several hundred degrees, and pressures far above atmospheric, and an airstream a few hundred MPH in velocity.

The inspection process for the individual blades, and then then for their attachment to the mount, to ensure that an imbalance doesn't destroy the engine is tremendously demanding.

On the other hand, there is a case to be made for an aim-for-the-stars strategy. If you can build a turbine blade you can build anything. I would have thought compressor blades would be a much more likely candidate, but if they can get this to work, more power to them. And maybe 3d printing will give them options they would not otherwise have: internal bleed air cooling channels that follow the leading edge along its curvature, for instance. It's possible that given completely different design and manufacturing capabilities, they'll be able to make something that can do the same job with different tradeoffs.

Comment: Re:Black Mirror (Score 1) 257

by smellsofbikes (#49138579) Attached to: 5 White Collar Jobs Robots Already Have Taken

But at some point people will notice that their friends and neighbours are being burnt. The point is that you have to pacify the majority or else they turn on those in power.

In Brave New World, the proles had drugs and sex to keep them happy: it's a much better prediction of the future than 1984 in many ways.

As Martin Niemoller said, in a different context:
"First they came for the Socialists, and I did not speak out—
Because I was not a Socialist.
Then they came for the Trade Unionists, and I did not speak out—
Because I was not a Trade Unionist."
and so forth. If they first kill off the homeless, then they kill off the very poor, then they kill off the illegal immigrants, they never have to pacify the majority. They just have to keep them scared enough to not protest.

By the way, Neil Postman wrote an interesting book called "Amusing Ourselves To Death", where he compared the futures predicted by Brave New World and 1984 and talked about why he thought we were heading towards Brave New World. Some of his information is pretty dated -- he totally didn't expect the universal surveillance state we seem to be entering into -- but it's still an excellent exploration of what you're suggesting.

Comment: Does this make sense economically? (Score 1) 243

by smellsofbikes (#49132275) Attached to: The Peculiar Economics of Developing New Antibiotics

If it costs $1B to get a drug through the FDA approval process, and your prize is $2B, you will only play the game if you think you'll get your first or possibly second try through the approval process. If you have to start half a dozen and have them fail at various points through the approval process, you've already spent the potential prize money without winning it.

We might need to look at how safe drugs have to be before they can be FDA-certified. I've harped on this before but I know people who thought Vioxx was a lifesaver in treating their arthritis, and experienced a very significant change in health and happiness when it was taken off the market because of the harm it did to other people. If we insist on drugs that have statistically significant positive effects, with infinitesimal negative effects, we may run out of options and end up dying the way people did in the middle ages, while the drugs we need sit on a shelf somewhere, waiting for a different regulatory environment.

Comment: Re:Oops (Score 3, Informative) 132

by smellsofbikes (#49088889) Attached to: Resistant Bacterial Infection Outbreak At California Hospital

I'm seriously regretting any anti-bacterial soap I've used over the years right about now.

Don't be. We may breed triclosan-resistant bacteria by using antibacterial soap, but that doesn't mean we're breeding carbapenem-resistant bacteria -- the C in CRE -- by using triclosan. There is very little evidence that developed resistance to one type of antibiotic increases resistance to another completely unrelated antibiotic. Triclosan inhibits fatty acid synthesis, carbapenem inhibits synthesis of the peptidoglycans used in bacterial cell walls.

Comment: Re:A biological "race" condition? (Score 1) 96

by smellsofbikes (#49081561) Attached to: Researchers Block HIV Infection In Monkeys With Artificial Protein

My understanding of HIV is that when it infects human cells, it hijacks the tRNA (iirc) so that the human cells continue producing more HIV viruses. With the article describing synthetic antibodies binding to HIV, the virus is unable to infect human cells. So this would seem like a race condition where the antibody needs to get to the HIV *before* HIV has a chance to infect a human cell. How can this happen reliably?

Mostly through concentration: making sure there are 100x or more antibodies against HIV present than the cells HIV is targeting.
But it's also helped by binding affinity. When a receptor and a substrate bind, it's generally reversible -- they can join or separate, and there is a measurable equilibrium between the bound and unbound states, which is a function of concentration of both receptor and substrate, and a constant that reflects how well they actually stick together. Generally, antibodies are _vastly_ better at sticking to things because they're designed to be. (Okay, the 'designed to be' is not actually true but for the purposes of this, it's an okay approximation) So if your antibody/HIV binding affinity is 100x better than the HIV/cell binding affinity, and you have 100x more antibodies than target cells, the number of viral/cell bindings is going to be much lower than the number of antibody/viral bindings.

Comment: Re:Okay, so... (Score 1) 378

by smellsofbikes (#49008063) Attached to: Woman Suffers Significant Weight Gain After Fecal Transplant

This is interesting, because my diet, such as it is, is almost exactly the opposite. I eat just over 1 gram per kilogram of body weight of protein, and about the same amount of fat, and then fill in the rest with carbs. But I'm a bike racer, so in the winter that may be 3000 calories of 70% carbs, where in mid-summer that sometimes stretches to 6500 calories a day, close to 85% carbs -- and I can't manage to get through the summer without losing 10 kilos, at which point I'm below 6% body fat and health issues start showing up and I have to start adding some fats.
Metabolism is weird.
One of my microbiology professors used to say that he felt humans were giant life support units for mobile ecosystems. He felt that much of what we think and feel is actually manipulated by our bacteria to benefit them and deter invasion from other bacteria.

Comment: civil or criminal recourse? (Score 4, Interesting) 297

by smellsofbikes (#48989943) Attached to: Mississippi - the Nation's Leader In Vaccination Rates

I have a friend who, in her thirties, just got measles from one of her son's friends, and now she's lost her hearing -- a fairly common, and often permanent, complication of measles. She's trying to sue the parents, on the basis of one of them posting about how they didn't vaccinate their child because they didn't believe in it. She figures that if a person who has AIDS and has unprotected sex with people can be charged with murder -- a criminal act -- she should be able to win a civil judgment for at least negligence.
If it works, it could be an interesting new chapter in the vaccination story, and does raise the question of why AIDS is handled differently than measles.

Comment: Re:More ambiguous cruft (Score 1) 514

Scenario: terminatored corn is widely succesful and replaces regular corn. Something bad happens to stop Monsanto from delivering more seends. What will the farmers plant? They can't use seeds from terminatored corn since they're infertile, and they can't plant regular corn seeds since they no longer have any. Mass starvation follows.

Scenario: the bad thing that happens is Monsanto realizes that they have more than 60% market share, and raises the price 20:1, because they'll make an enormous profit. There's nowhere nearly enough regular seed corn to plant, so everyone has to pay the piper. It's a monopoly in the making, and you know Monsanto and many other businesses have already thought of this and are just wriggling with anticipation.

Comment: Re:the problem with how nuclear works in the USA (Score 3) 176

The reason why power companies do not invest in reprocessing and consume fresh fissile material is because by federal law bans it. Remember Jimmy Carter's Non-proliferation deal? Yeah.


"In October 1976,[8] concern of nuclear weapons proliferation (especially after India demonstrated nuclear weapons capabilities using reprocessing technology) led President Gerald Ford to issue a Presidential directive to indefinitely suspend the commercial reprocessing and recycling of plutonium in the U.S. On 7 April 1977, President Jimmy Carter banned the reprocessing of commercial reactor spent nuclear fuel. ...
President Reagan lifted the ban in 1981, but did not provide the substantial subsidy that would have been necessary to start up commercial reprocessing."
"In March 1999, the U.S. Department of Energy (DOE) reversed its policy and signed a contract with a consortium of Duke Energy, COGEMA, and Stone & Webster (DCS) to design and operate a mixed oxide (MOX) fuel fabrication facility. ... the government has yet to find a single customer, despite offers of lucrative subsidies."

It's nothing to do with the ban on reprocessing that was only in place from 1977 to 1981, and everything to do with reprocessing being completely uneconomical. If we're going to reprocess, the government has to pay for it, as companies won't, but there are no technical or legislative barriers to doing so, as multiple other countries that are already reprocessing their waste demonstrate.

Comment: Re:Apparently it works, but it can be dangerous (Score 1) 154

This podcast seems to be about tDCS, while Thync is appearantly "using transcranial pulsed ultrasound (tPU), transcranial direct current stimulation (tDCS) and other transcranial electrical stimulation (tES) methods".

I dated a woman who was involved in transcranial magnetic stimulation projects. She said it was like someone was flicking the inside of her brain, and similarly to tdcs, it had significant effects on her mental abilities: she'd sometimes be measurably better at math, or measurably worse at coming up with words during conversations. I hadn't heard of tpu before.

Comment: Re:Blind experiment (Score 4, Interesting) 154

by smellsofbikes (#48760095) Attached to: Thync, a Wearable That Zaps Your Brain To Calm You Down or Amp You Up

Have a patch that doesn't actually apply voltage, but vibrates or something like that. User still feels like he/she is getting some sort of effect, but there's no brain-zapping involved.

In the Radiolab discussion, they were doing tests with the woman who was doing the sniper training, both with and without the system running. She thought her performance was about the same, but the people analyzing it said it was dramatically different, because among the things affected was her perception of time. She felt like she was playing the game until she got killed, which was maybe a matter of a minute or two, but when she was playing really well, she was playing for much longer periods of time and didn't realize it.
As I recall, they specifically compared it to programmers who talk about The Zone, where they're coding very effectively and have reduced perception of the passage of time, and making the claim that the two effects, of heightened efficiency and reduced perception of time passage, may be related.

Comment: Apparently it works, but it can be dangerous (Score 5, Informative) 154

by smellsofbikes (#48757809) Attached to: Thync, a Wearable That Zaps Your Brain To Calm You Down or Amp You Up

There was a recent Radiolab about this general technique, that's totally worth listening to:
(It's also a lot better-written than the summary.)

The idea is that by applying DC voltages to different parts of your skull, you can affect how your brain works. The theory is that the current passing across part of your brain changes how your brain learns from mistakes, messing with the pattern-acquisition feedback. In the story, they specifically concentrated on a woman training in a sniper video game, who was having to identify attackers vs. civilians, and how much it changed her ability to do that, but they also discussed a big underground scene of people trying this out at home for other purposes or just to learn about what happens. They were moving the contact patches around and then trying things to see what they were or weren't good at. One guy doing this found a spot that left him largely blind for several hours afterwards, so it's not all roses, but the people trying language acquisition and finding it much easier both to acquire and, later, post-treatment, to recall, new languages, really got me interested.

Comment: Re:Speaking of Radio Shack (Score 4, Interesting) 61

by smellsofbikes (#48749835) Attached to: DuinoKit Helps Teach Students About Electronics (Video)

I seriously wonder why RS hasn't embraced the maker culture. It seems to me that they can only last another year trying to compete in consumer products and batteries.

Do you remember TechAmerica, RadioShack's last attempt to embrace the maker culture, in 1996? They opened five stores in major metro areas.
They were wonderful. I could go in and decide which 10-bit A/D I preferred. The guy behind the counter knew what a 74141 was.
They lasted five years. Over the three year lifetime of the Denver store, the electronics section got smaller, the toys and gadget section got larger, and they still didn't manage to make their rent.

After that, is it any surprise that their current maker section consists of half a dozen arduino boards and shields and a shelf of TH resistors in the back? How do you compete with Digikey, if you have to pay rent?

The universe does not have laws -- it has habits, and habits can be broken.