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Comment Re:Off-Earth habitation (Score 1) 684

No, the rotating space station should be much cheaper. Note that it does not have to be a big doughnut as in "2001" - we could just separate the nuclear reactor from the manned part, connect them with a cable, and set them to rotating. Any deep space transit craft should be set up the same way (except there you'll have nice heavy fuel tanks for the counterweight), so the astronauts arrive healthy.

Comment Re:Worse than the space station? No. (Score 1) 684

You may find it convenient to get part of your power from solar panels, but it does entail a big capital investment. The batteries or grid-connected power for night time power would be another big capital investment. Currently many of the power companies are using gas-fired generators to minimize that investment (and to enable them to ramp up quickly when solar or wind power suddenly drops). You suggest backing up the solar with nuclear, and that can work. However, the current generation of nuclear power requires an even bigger investment in capital. Few owners want to let any significant amount of its capacity go unused. I think the ideal approach is to (1) invest today in enough research that the next generation of nuclear power (e.g., LFTR) will be much less expensive, (2) also invest in battery technology for grid-connected storage, (3) put a price on carbon dioxide emissions, (4) let the price of electricity float during the day, and (5) let the market decide what combination of solar panels, extra nuclear capacity, and grid-connected storage makes the most sense.

The real fantasy is that the 600M people in India without electricity could rely on solar power. They do not have the land or the money to invest that way.

Comment Re:Not so much outdoors (Score 1) 60

"Time spent with eyes focused on close objects (such as reading or computering) = myopia." RIGHT.

How it's supposed to work: Child is born farsighted -> much time spent outside looking at distant objects, but focusing muscles in the eye can still bring those objects into focus -> muscles get tired -> brain concludes "I'm still farsighted" -> eyes grow -> eyes can relax most of the time - i.e. while looking at distant objects = perfect vision.

How it's working in industrialized countries: Much time spent with eyes focused on close objects -> focusing muscles in the eyes get tired -> brain concludes "I'm still farsighted" -> eyes grow -> eyes can relax most of the time - i.e. while looking at CLOSE objects = myopia. If you get glasses that "correct" for myopia, and wear them while reading, then you go around the loop again and the myopia gets worse. That's what happened to me - I need a correction of -4 diopters or so.

Lesson #1: if you have myopia, so you need glasses for distant work, then take those glasses off if you're doing a lot of close work. Or else get bifocals.

Lesson #2: To prevent myopia in the first place, get kids to wear READING GLASSES (+1.5 or +2 diopters) while doing a lot of close work. That way their eyes are focused at infinity (therefore relaxed) even though they're doing close work. My daughter was willing to do this, because it was only while she was at home working on the computer or reading, and not when she was out with other kids. She graduated as an engineer, and still doesn't need glasses.

Comment prevention...cure...treatment...diagnosis (Score 2) 204

...in decreasing utility far as the patient is concerned. Unfortunately, as far as the medical-industrial complex is concerned, "expensive treatment for the duration of the patent" is the primary goal, with cures and vaccinations to be avoided if possible. We'll be stuck with that as long as medical research is paid for out of drug company profits. If, on the other hand, we had a "single payer" health care system, the federal government would have an incentive to fund research into cures and prevention.

Comment earthquakes are not necessarily bad (Score 1) 264

The notion that pumping water underground causes earthquakes has been around quite a while. What bothers me is the knee-jerk reaction that this is necessarily a bad thing. The choice is not between an earthquake or no earthquake. Rather, it's between an earthquake now, or a bigger earthquake later. Remember that the energy of the earthquake comes from strain in the rocks, which in general is continually building (due to shifting tectonic plates, moving magma, etc.). If it's not released now, then the strain will just build until it's released later - and you get a bigger earthquake.

I will grant there might be a few cases where I'd rather reduce the chances of an earthquake in the short term, even if it made the eventual earthquake worse (say, if I just discovered a weakness in a dam, and will be spending the next two years madly strengthening it). But in general I would rather have more, smaller earthquakes.

Comment Re:Chemical battery efficiency is quite poor (Score 1) 347

Li-ion batteries in laptops and cell phones don't last long, but for automotive use they're using a different electrode (lithium manganese oxide instead of lithium cobalt oxide - see http://www.technologyreview.com/printer_friendly_article.aspx?id=26832) which they think will last a lot longer. I'd like to know when I can get the longer-lasting kind for my laptop. Or would they rather design in a short product life?

The Effect of Internal Bacteria On the Human Body 227

meckdevil writes with this excerpt from the Miller-McCune magazine: "In a series of recent findings, researchers describe bacteria that communicate in sophisticated ways, take concerted action, influence human physiology, alter human thinking, bioengineer the environment and control their own evolution. ... The abilities of bacteria are interesting to understand in their own right, and knowing how bacteria function in the biosphere may lead to new sources of energy or ways to degrade toxic chemicals, for example. But emerging evidence on the role of bacteria in human physiology brings the wonder and promise — and the hazards of misunderstanding them — up close and personal. ... Because in a very real sense, bacteria are us. Recent research has shown that gut microbes control or influence nutrient supply to the human host, the development of mature intestinal cells and blood vessels, the stimulation and maturation of the immune system, and blood levels of lipids such as cholesterol. They are, therefore, intimately involved in the bodily functions that tend to be out of kilter in modern society: metabolism, cardiovascular processes and defense against disease. Many researchers are coming to view such diseases as manifestations of imbalance in the ecology of the microbes inhabiting the human body. If further evidence bears this out, medicine is about to undergo a profound paradigm shift, and medical treatment could regularly involve kindness to microbes."

West Virginia Is Geothermically Active 239

sciencehabit writes "Researchers have uncovered the largest geothermal hot spot in the eastern United States. According to a unique collaboration between Google and academic geologists, West Virginia sits atop several hot patches of Earth, some as warm as 200C and as shallow as 5 kilometers. If engineers are able to tap the heat, the state could become a producer of green energy for the region."

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