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Comment: Re:And what good would it do? (Score 1) 447

by Reziac (#49388829) Attached to: Why the Final Moments Inside a Cockpit Are Heard But Not Seen

Too little or too much iodine can fuck up your thyroid (only because it uses iodine directly), but otherwise it's not real sensitive to lifestyle or diet... however it can influence what you want to do and eat (low thyroid causes sugar craving and lack of motivation/energy to do anything). TSH levels fluctuate depending on iron, selenium, and sugar intake, but there's no strong evidence that any of these will cause more than transient deficiency; indeed, low thyroid is a known cause of poor iron absorption, so it's rather the reverse -- eat well and you still won't get good use of it. At least one gene has been identified that causes poor T4-to-T3 conversion, IOW the DNA that controls the required enzyme is defective. Anyway, if you try treating hypothyroid with diet and exercise you won't get far. I can point at myself as a good example -- I'm more active than most folks (I've done physical work my whole life) and I eat almost entirely home-cooked, nutrient-dense food, but that doesn't do a thing for my Hashimoto's.

Comment: Re:And what good would it do? (Score 1) 447

by Reziac (#49373311) Attached to: Why the Final Moments Inside a Cockpit Are Heard But Not Seen

If I find that particular paper again I'll let you know. And depression as a consequence of subclinical hypothyroidism is very well established, but no longer generally acted upon. It used to be routinely treated as such, but when the TSH test came to prominence, most doctors started treating to make nice test results rather than treating the patients' symptoms.... despite that all the evidence is against using TSH as anything but a crude marker that something is wrong. False negatives are extremely common.

Here's a starter kit:

I have Hashimoto's thyroiditis, and I've had to take up reading the Journal of Endocrinology in sheer self-defense. It's quite shocking how much well-established endocrine research has never filtered down to GPs, never mind other specialty fields, despite that a malfunctioning endocrine system can fuck up just about anything else. I've concluded it should be the first line of inquiry (since fixing the thyroid will commonly cure a whole raft of apparently-unrelated physical and mental symptoms), but most doctors act like it's the last resort.

Comment: Re:Space debris (Score 1) 221

by DanielRavenNest (#49372199) Attached to: Chinese Scientists Plan Solar Power Station In Space

> I think a large problem is going to be space debris -

Nope. If you can build giant solar arrays in GEO, you can build small ones and attach ion thrusters to them. See the Dawn mission at Ceres and the Asteroid Redirect Mission NASA is proposing for examples. These space tugs can putter around and collect loose space debris. That however does not eliminate natural meteoroids. So your power satellite will need a maintenance program, or just accept a small amount of degradation as stuff hits it.

Solar arrays are thin, so most debris will just punch a small hole.

Comment: Re:The Chinese advantage (Score 1) 221

by DanielRavenNest (#49372135) Attached to: Chinese Scientists Plan Solar Power Station In Space

> The biggest unknown is the microwave link to send power to Earth.

We actually have tons of data about this, from all the GEO communications satellites, and rain fade that happens sometimes.

> The next-biggest unknown is availability of construction materials.

I was one of the people who worked on this issue while at Boeing. We found that 98% of the materials for a solar power satellite can be obtained from the Moon. A higher percentage are available if you use the Moon + Near Earth Asteroids. We didn't do the numbers for the NEO case back in the 1980's, since we had only discovered ~150 back then vs 12,500 today, and ion thrusters were not fully developed until about the year 2000. A modern study would account for both sources of materials.

Comment: Re:Sim City (Score 2) 221

by DanielRavenNest (#49372025) Attached to: Chinese Scientists Plan Solar Power Station In Space

We solved that problem early in the Solar Power Satellite studies at Boeing. The microwave transmitter in orbit is a phased array. The reference signal to adjust the phase is a transmitter in the center of the rectenna on the ground, powered by the rectenna. If the beam wanders off target, no reference signal, and the beam is no longer focused.

Comment: Re:No they don't (Score 1) 221

by DanielRavenNest (#49371915) Attached to: Chinese Scientists Plan Solar Power Station In Space

Hi Maury,

* Spectrolab rates their space solar panels for 20 years at GEO: Since they don't need to withstand weather, they can be much lighter than ground-mounted panels. 13 W/kg for a typical ground panel (not counting mounting and tracker) vs 177 W/kg for the space ones. That has implications for the energy payback time if you manufacture the panels in space.

* Your comparison of operating hours neglects that in space you have 36% higher insolation, because there is no atmospheric absorption. Therefore it takes fewer cells to produce the same output. Also the Nevada desert is an excellent location on Earth. The average location on Earth gets considerably worse hours of sunlight. Since we can't transmit power all over the Earth, cherry-picking a good location is unfair.

Comment: Re:And what good would it do? (Score 1) 447

by Reziac (#49371709) Attached to: Why the Final Moments Inside a Cockpit Are Heard But Not Seen

Probably the most common cause of depression is subclinical hypothyroidism, specifically with low T3. One psychiatrist found that he could cure 90% of his patients by prescribing T3 to bring their active thyroid hormone level up to normal. (Prescribing T4 alone didn't work, probably because poor T4-to-T3 conversion is part of the problem here.)

Comment: Re:DVD patents expiring (Score 2) 68

by evilviper (#49363805) Attached to: Another Patent Pool Forms For HEVC

At least the patents on DVDs are expiring if not already expired. The first DVD player was sold in 1996, and patents can be good for up to 20 years from the filing date, so it would seem that by late next year, all necessary patents should have expired.

This is HORRIBLE legal advice. Patent laws were different before 1996, that's why MP3 patents are still around (and will be until 2017) despite the fact that specifications were published back in 1991!

In the United States, "patents filed prior to 8 June 1995 expire 17 years after the publication date of the patent, but application extensions make it possible for a patent to issue" quite a few years after initial filing.

MP3 patents have mostly expired, though one US patent expires later this year.

I wish that was true, but it's certainly not:

Comment: Re:What if... (Score 1) 71

by DanielRavenNest (#49361225) Attached to: US Air Force Overstepped In SpaceX Certification

SpaceX couldn't get an export license then. Rockets fall under the "International Traffic in Arms Regulations" (ITAR) and need a license to export. We even had to follow those rules for the Space Station modules being built by Boeing. That's despite it being an international station occupied by lots of foreigners, Russians even.

Comment: Re:I'd put a 'may' there (Score 2) 42

by DanielRavenNest (#49361151) Attached to: Taxpayer Subsidies To ULA To End

> It does seem that the ULA has been mostly sitting on their laurels sucking at the government teat for a long while now.

Let me explain how this works. At the start of the Sea Launch program, which Boeing was a partner of, and I was working on, our program manager was an ex-Air Force officer who was a launch director from Vandenberg (where the Air Force launches polar satellites). He was a smart and competent guy, but the main reason Boeing hired him is *he knew all the right players on the Air Force side*. Another manager of mine was a former Marines officer who had done helicopter procurement.

When the people who make the buying decisions already know you, because they used to work with you, you have a much better chance than someone they never met before and have no idea how good they are, if they will get along, etc. This "revolving door" works in the other direction too, where someone in industry then goes to work in government, in the same field. The problem is you often can't find anyone else who is qualified to oversee such contracts.

Adding features does not necessarily increase functionality -- it just makes the manuals thicker.