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Comment: Re:The lights... (Score 1) 403 403

There's a lot of wear on the turbine systems. They require weekly to monthly checks of bearings and regular lubrication and maintenance. I doubt that Hoover Dam would operate without maintenance for 50 years just as you could not run a car for a decade without ever changing the oil.

Comment: Re:Atomic clocks don't rely on nuclear decay..... (Score 1) 403 403

Atomic clocks won't work without electrical power, and would be subject to all the same physical rust and breakdown as other electronic devices over the years.

Indeed. I used to work at the Time and Frequency division at NIST, where they keep the master atomic clocks for the US. They had a big room full of 12-volt car batteries to provide backup power to the clocks in case of a power outage.

Comment: RTGs in lighthouses (Score 3, Interesting) 403 403

The former Soviet Union built hundreds of automated lighthouses in remote locations powered by radioisotope thermoelectric generators. Those use 90Sr, which has a half-life of 30 years so they can go for many decades. They were installed in the 1970s-90s, so most of them are around one half-life out. They could well continue operating for several decades, but some small solar-powered devices might well outlast them if they aren't damaged too badly by weather over the years.

Comment: Re:K-12 Teacher (Score 1) 420 420

right now most of us are going to have many careers in our lifetime.

The idea that people are going to have many careers, and that people are changing jobs more frequently than in the past appears to be an urban myth that is not supported by actual data.

job stability hasn't changed all that much in the U.S. since the late 1990s ... the typical American worker's tenure with his or her current employer was 3.8 years in 1996, 3.5 years in 2000 and 4.1 years in 2008, the latest available data.

Comment: Re:She has a point. (Score 1) 628 628

Also, if we look at real tenure track hirings, as opposed to hypothetical ones in a research study, we find that women are 35% of tenure-track hirings in biology, 30% in chemistry, 30% in civil engineering, 30% in electrical engineering, 30% in math, and 20% in physics.

This is hardly evidence that women "utterly dominate virtually every measure of academic success and achievement we have at pretty much every level."

Comment: Re:She has a point. (Score 1) 628 628

And here is another study, which finds the opposite: When men and women perform equally well at mathematical tasks, the man has a two-to-one advantage over the woman at getting hired.

We studied the effect of such stereotypes in an experimental market, where subjects were hired to perform an arithmetic task that, on average, both genders perform equally well. We find that without any information other than a candidate’s appearance (which makes sex clear), both male and female subjects are twice more likely to hire a man than a woman.

Comment: Re:She has a point. (Score 1) 628 628

Women currently have a 2:1 advantage in STEM fields

This is nonsense. According to the latest numbers Women get 49% of all bachelors degrees in STEM fields and 40% of doctoral degrees, but if you look at individual disciplines there are very big disparities: Women are 18% of computer science majors, 19% of engineering majors, 38% of geosciences majors, 39% of physical science majors, 42% of math majors, and 58% of agricultural and biological science majors.

Moreover, this report shows that the fraction of women in STEM fields has gone down over the last decade, most sharply in computer science.

But nowhere in this report do we see that women have an overall two-to-one advantage in STEM disciplines.

Comment: Re:uhhh (Score 3, Interesting) 138 138

Just because a fossil looks similar does not mean it hasn't evolved. Most evolution happens on the molecular scale, if you looked at the genomes I guarantee they would be different.

The paper in PNAS discusses this at length. It clearly states that it would be very nice to be able to check DNA, but that defining species in microbes is about phenotypes, not genotypes, and the important thing is that there is no sign of speciation (that is, two separate populations, separated in space, did not diverge.

The morphology-based “concept of hypobradytely does not necessarily imply genomic, biochemical, or physiological identity between modern and fossil taxa," a claim of extreme evolutionary stasis—a lack of speciation over billions of years—would be strengthened not only by discovery of additional fossil communities but by firm evidence of their molecular biology. Although speciation-based evolution occurs at the phenotypic rather than genotypic level of biologicenvironmental interaction, the biomolecules underlying such change are not preserved in the rock record in which such assessment can be based only on indirect proxies and inferences of physiology based on isotopic analyses

However, the article noted, it's possible that this interpretation is wrong and that what they saw was two separate populations that underwent convergent evolution rather than one population that was separated and remained static or that there might have been significant biochemical evolution that did not change the morphology.

Moreover, large-diameter (“giant”) sulfur bacteria of differing phylogenetic lineages can exhibit similar morphologies and patterns of behavior suggesting convergent evolution of morphologic “look-alikes” adapted to a same or similar function. Although it remains to be established whether such morphological “mimicry” is exhibited also by the more narrow 10-m-diameter sulfur bacteria described here—the two modern sulfur bacterial taxa of similar dimensions being aerobes rather than anaerobes like the Duck Creek and Turee Creek fossils—it remains conceivable that the marked similarities between the two mid-Precambrian communities and their modern counterparts could be an example of the so-called Volkswagen Syndrome, a lack of change in organismal form that masks the evolution of internal biochemical machinery

Comment: Re:Professors now make big bucks teaching (Score 1) 94 94

You're exaggerating the salaries: Median salaries for tenured Associate Professors is a bit under $70K. Median salaries for tenured Full Professors is a bit under $100K. Not bad, but not the "$100k-200k" that you describe.

Few universities have pensions these days. They mostly have 403(b) retirement plans, which are basically the same as 401(k)s: Faculty contribute their own money and get matching up to some maximum (usually around 5 to 10 percent). How is that unmatched in the private sector?

Comment: Re:Windows (Score 1) 203 203

The biggest missing solution: - Windows server support. There are some expensive solutions, not sure how well they work.

I've been using the Bitvise sshd server on Windows for about 10 years with no problems. It's free for noncommercial personal use and $100 (plus $20 per year for upgrades) per host for a full license if you're using it for business or commercial purposes. This doesn't seem "expensive" to me, but YMMV of course.

Comment: Re:Sure... (Score 1) 343 343

Climate models may one day mature to something beyond the basket of hypotheses they are now, but none of them have yet been successful in predicting climate data, except where the null hypothesis also predicted that data.

Wrong. Manabe and Wetherald predicted in the 1960s that greenhouse warming would cause the stratosphere to cool when the troposphere warmed, whereas increasing solar intensity (the null hypothesis) would cause both the stratosphere and the troposphere to warm simultaneously.

The observed temperature trends agree with the greenhouse warming predictions and disagree with the brightening sun predictions.

Subsequent modeling work predicted dozens of ways in which the greenhouse warming and brightening sun would produce different patterns (e.g., greenhouse gases would cause nighttime temperatures to warm more than daytime temperatures, whereas increasing the brightness of the sun with no change in the greenhouse effect would cause days to warm more than nights). And today when we look at the patterns of observed warming, they overwhelmingly agree with the greenhouse warming predictions and disagree with the brightening sun predictions.

Comment: Re:Sure... (Score 1) 343 343

I don't think I understand what you mean by "air gapping."

Are you saying that employees should not be able to send email to computers located outside the company's headquarters, receive email from computers outside the company's headquarters, and or read their email without physically going to the corporate headquarters (e.g., no checking business email from the road, branch offices, or home)? If that's what you mean by "air gapping" it doesn't sound practical.

Comment: Re:Numbers: How many trees would it take (Score 1) 363 363

I notice they leave out the part where it returns to the atmosphere through tree rot.

You can preserve the wood in dry or anaerobic conditions to prevent rot after the tree is harvested, but that would take extra effort and energy.

However, it's not unreasonable to imagine that in 100 years the energy for doing that sort of thing might be available from renewable or nuclear sources.

Also, if you replant a new tree where the old tree stood, the new tree could absorb the CO2 emitted by the old tree's rot. But you would have to understand that the replacement tree is just preserving the sequestration that the older tree accomplished, not adding any new sequestration if the old tree is allowed to rot. Thus, if we were to go on using fossil fuels there would be a tradeoff between the energy and effort required to preserve old wood and the land required to keep expanding the forests.

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