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Comment Re:Examples of Global Agreement. (Score 1) 104

Even so in the parts of Alaska outside of the Arctic Circle there's summers where the sun rises at 3AM and sets at 9PM, then in the winter it's sunrise at 9AM with sunset at 3PM.

In Fairbanks at the winter solstice the sun rises at 10:58 and sets at about 14:40.

At the summer solstice it's 02:57 and 00:47. Even though the sun officially sets year round it never really gets dark between mid April and mid August because the night periods never leave the twilight stage.

Comment Re:Short term gains for long term pain (Score 1) 148

That *should* mean there are more males at the bottom end where people really need help

More at the top and more at the bottom, and the effects on earnings are not symmetrical. Once somebody is cognitively deficient enough to be considered a ward of the state the amount of resources they require to survive remains more or less constant with diminishing IQ but on the other end of the curve income potential does not have an corresponding cap.

Comment Re:Short term gains for long term pain (Score 1) 148

I watched a guy from Scandinavia doing a interview recently, and talking about these topics. One fact that blew me away was that on average men are overall contributors to the welfare state over their lives, and women, on average, receive 1.3 million (he said dollars - not sure what currency precisely) from the welfare state over their lifetime.

In Scandinavia you see sex-based differences in group averages and in the US those same measurements show both sex-based and race-based differences in group averages.

Comment Re:Hoping it works (Score 1) 109

Building a 10 GW or even 100 GW nuclear reactor is no big deal. There are no special engineering challenges and reactors of that size would substantially more cost effective to build because construction and operation costs scale less than linearly.

The only problem is finding practical ways to consume all energy. Nobody wants a 100 GW point source of electricity on the grid because even if you build the transmission lines to distribute all that power one plant would be such a large fraction of the supply that if it went down you'd instantly get a blackout.

Comment Re:Hoping it works (Score 1) 109

Traditionally we tried to keep neutron absorbers away from the reactions unless you want to halt the reactions.

One of the advantages of a liquid fuel design is that the two most significant fission product poisons (iodine and xenon) can easily be removed from the solution since they are gasses at those temperatures. This frees up a large fraction of the neutron budget which can then be used to transmute thorium into uranium.

Comment Re:The USA will follow in about three years (Score 3, Interesting) 109

What is likely a much larger concern is producing Pu-239.

A reactor burning pure U-233 would produce very little in the way of transuranics.

The thing about a liquid fuel reactor though is that since you don't need to disassemble it or even shut it down to add more fuel you have an unprecedented flexibility in terms of what you can burn. Within certain limits you can use almost any fuel mixture.

The most obvious way to scale up a MSR industry is to start out burning a traditional U-235 / U-238 fuel mix while you breed U-233 from thorium. Then once U-233 production is sufficient you can quit enriching to obtain U-235 and just replace it with U-233 while still using U-238 (natural unprocessed uranium) for the bulk of the fuel. If for example your MSR design can tolerate 10% U-233 (U-235) / 90% U-238 then you can scale up the industry ten times faster than if you tried to start out using 100% U-233 from the very beginning.

At some point in the future when you are no longer increasing the reactor count at a rate that exceeds the achievable breeding rate of U-233 you can start increasing the U-233 / U-238 ratio until eventually you no longer need U-238 at all.

Along the way you can decide how to allocate your spare neutron budget. When you no longer need to breed U-233 as rapidly as possible some of those spare neutrons can be used to dispose of problematic isotopes, decommissioned nuclear weapons, etc, but in the early stages you are running reactors that use a substantial amount of U-238 so they would produce as many transuranics as traditional reactors produce.

Submission + - California squirrels show carnivorous behavior for the first time (cnn.com)

Hmmmmmm writes: Traditionally known for stuffing their cheeks with nuts, squirrels can be carnivorous — though recorded instances of the rodents hunting and killing other live vertebrates are rare, with few species known to have done so. Now, scientists have found unprecedented evidence of another type of squirrel exhibiting carnivorous behaviors, including hunting, killing and eating voles, according to a new study.

The research, published Wednesday in the Journal of Ethology, is part of the Long-Term Behavioral Ecology of California Ground Squirrels Project at Briones Regional Park in Contra Costa County. The project examines how California ground squirrels — native to the state’s grasslands — adapt their behavior in response to environmental changes, in this case an increase in the local vole population.

In parts of Northern California, vole infestations have been observed. At the research site, the study’s authors noted a significantly higher number of voles than average over the past decade. California ground squirrels have typically been considered herbivores or granivores, eating mostly plants and seeds. The new findings offer the first documentation of the species actively preying on other live vertebrates — underscoring its ability to respond to changes in the ecosystem.

  “Voles (have come to) recognize the squirrels as predators,” said John Koprowski, dean of the Haub School of Environment and Natural Resources at the University of Wyoming, who was not involved in the study. “There’s likely some really neat interplay between the two species because being eaten is usually not a great way to continue passing on your genes.”

The study’s findings suggest squirrels might be best classified as opportunistic omnivores based on their willingness to hunt and consume live prey, particularly when there is an abundant supply. Protein is a limited yet necessary resource for squirrels to thrive, and hunting voles likely provides them with a faster, more accessible nutrition boost than seeds, Koprowski explained.

“It’s a wonderful way for them to capitalize on a very abundant resource to provide enough sustenance for many (squirrels) to use,” he said.

This phenomenon in which an animal capitalizes on a necessary resource when it’s made available to them is known as dietary plasticity, according to Koprowski. If an animal doesn’t adapt to utilize the resource, it’s likely another species will take advantage of it.

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