mistermack

I think for a given temperature, density is directly related to pressure, so if you want increased density, you have to increase pressure. In the Sun, the pressure is presumably pretty constant, so the density goes up and down with temperature, which stabilises the fusion rate. Wikipedia is interesting on that : "The fusion rate in the core is in a self-correcting equilibrium: a slightly higher rate of fusion would cause the core to heat up more and expand slightly against the weight of the outer layers, reducing the density and hence the fusion rate and correcting the perturbation; and a slightly lower rate would cause the core to cool and shrink slightly, increasing the density and increasing the fusion rate and again reverting it to its present rate."[88][89] Another interesting fact is that the Sun's core only produces as much heat per unit volume as the average reptile, or compost pit. On pressure and density, wiki says this about confinement : Confinement[edit] The key problem in achieving thermonuclear fusion is how to confine the hot plasma. Due to the high temperature, the plasma can not be in direct contact with any solid material, so it has to be located in a vacuum. Also, high temperatures imply high pressures. The plasma tends to expand immediately and some force is necessary to act against it. This force can take one of three forms: gravitation in stars, magnetic forces in magnetic confinement fusion reactors, or inertial as the fusion reaction may occur before the plasma starts to expand, so the plasma's inertia is keeping the material together.

I see pain as a method of persuading (or forcing) you to favour a damaged part of the body, until it has repaired itself. If the brain keeps getting the damage signals, then it will continue giving the pain sensation. Some things can't be repaired, so the signals don't go away. Or maybe something does get repaired, but the damage signal keeps getting sent in error. Or maybe even the damage signal gets sent in complete error for no good reason. I don't see any evolutionary benefit in the body "stress testing" body parts. I'm not aware that repair is stimulated by the pain sensation in the brain. I don't find it likely, although can't say that I know anything to the contrary.

They are for the same amount of gas. But if you have two reactors running at the same temperature, then the one that achieves a higher pressure would be more effective, because the plasma would be denser, meaning more frequent collisions, and a higher probability of a suitable collision. I just read that the critical factors are called the "triple product" of density of plasma, temperature and time, for a fusion reactor. https://en.wikipedia.org/wiki/Lawson_criterion

Nothing to do with breeding. There's an effect of diet and health of parents that can persist over two or three generations, leading to size and health difference of children. African lifestyles are not generally a match for the USA or the West Indies. But that's focusing on the power sports. Endurance sports like the Marathon and other distance running are dominated by Africans born in Africa. Edit : You've also got better training facilities in the US and better chemists and pill pushers. Makes a difference in strength disciplines.

Presumably you would monitor the temperature of the rock you are drilling, and stop when it got hot enough for your purposes, so you wouldn't be reaching liquid lava. Once you start injecting water, you would be tending to solidify the nearest lava, so it wouldn't be inherently dangerous. ( I think )

Without researching the matter, I'm suggesting that pressure comes into it as well as temperature. Inside the Sun, pressures are phenomenal due to the huge gravitational forces. When the nuclear fission trigger goes off in an H bomb, the pressures are presumably enormous too. It's very difficult to reproduce those kind of conditions in a fusion reactor, especially the pressures, so I'm guessing that they have to get the plasma to higher temperatures than in the Sun or an H bomb to compensate for lower pressures. They actually repel each other with electrostatic force, and need the high temperatures and pressures to overcome that. Once they get past that barrier, the nuclear force, which acts over shorter distances, takes over and they then want to fuse. When they fuse, the resultant mass is slightly less than originally, the missing mass is converted to heat and light in huge quantities.

As far as I'm concerned, this is another case of the USA having ludicrous law in place. How can a 13 year old child be considered to have given civil or criminal consent? It's making a joke of the law. He can't legally consent for criminal purposes, but he can for civil purposes. The law is a joke. If you are going to say that a 16 year old girl is under age for sex, then she can't consent either. If the legislators think that 13 and 16 year olds can be held responsible, then they should be lowering the age of consent. At present, the message is "you can't consent, unless it is going to cost us money, in which case, you did consent". Ludicrous.

I've often wondered why more use isn't made of volcanoes, but it's probably the unpredictability that puts off investment. The course of flows can change without warning, making it dangerous and financially risky. I don't think you'd have to pump water to the top, you could drill into the side till you struck a significant heat source. Iceland might be a good place to research, they have more geothermal per person than anywhere else, by a big margin.

My answer is "don't know" to all of the questions. I don't know of "the" definition of virtually anything. If I need one, I look it up, and don't always agree with what I find. When it comes to real and imaginary, I form an opinion in each case, if I need to.

They are. And on land, the elephant is also considered up there as one of the most intelligent. It's a bit hit and miss really. Why intelligence develops seems to be a bit haphazard. In a lot of cases, it seems linked to communal living, but not all, as the octopus illustrates.

In the sea, the most intelligent creatures ARE generally the bigger ones. Even with sharks, the great white is reckoned to be one of the most intelligent fishes. On land, the most intelligent creatures happened to evolve up in trees, which limits size. There was a giant ape that went extinct, but we don't know much about it, or it's intelligence level. Humans have increased in size a bit, since our ancestors left the trees. But it's skill with weapons that have made us a dominant predator, and that takes the evolutionary pressure off the physical strength characteristic.

I would like to see some evidence for that.

I quoted the world bank and the UN. You quoted someone's blog. It's not really on the same level.

If you look at the World Bank graph I posted earlier, you can see that there are five billion people on the planet who's population rise is extremely steep and even climbing. ( The two asias and sub saharan Africa, add them up ) I think the UN estimates that I posted are extremely optimistic.

"The current world population of 7.6 billion is expected to reach 8.6 billion in 2030, 9.8 billion in 2050 and 11.2 billion in 2100, according to a new United Nations report being launched today. With roughly 83 million people being added to the world’s population every year, the upward trend in population size is expected to continue, even assuming that fertility levels will continue to decline." The UN. https://www.un.org/development/desa/en/news/population/world-population-prospects-2017.html

Yes, by which time population will be nearly double. ( I predict ) AND, along with tackling poverty etc comes more demand for energy.

That's rather silly. In any case, it's not a question of speeding up a decrease. We haven't got a decrease. And by the time we do get any decrease, the population levels will probably be double what we've go now. : World bank data : Brazil has shown that population rises are not inevitable, but that was a local freak, nothing to do with deliberate actions.

It's not worth the name of climate prediction. A fifty fifty coin toss that I could do sat on my arse. In any case, there is no official climate prediction. There are thousands of stabs in the dark. That way, someone is bound to get it right. IF they had predicted nearly twenty years of no rise in temperatures, I would have been impressed. But they didn't. They predicted huge rises in temperatures that never happened. That was before they started fiddling the figures. Now, what's really happening is anybody's guess because figures are being manipulated. I used to trust the reported figures, now I don't. It's open season.

I said climate science as a movement. I don't work in climate science. Nobody in their right mind would go into climate science as a sceptic. Predicting a RISE isn't a climate prediction. It's no better than a coin toss. Actually they are. They are burning jungle, and making babies, who will one day demand cars and air conditioners and plane journeys. In the developed world, CO2 output is generally falling and populations would be too, without immigration from the developing world.

It's pretentious to present the argument as wise scientists against moronic sceptics. The fact is that climate science as a movement isn't an unbiased clinical body, it's a world of activists. All dissent has been eliminated. And the other fact is that it's a brand new science with NO record of successfully forecasting the world climate. Absolutely nil. Zero. They are overclaiming their expertise by a huge margin. In fact most of the dire predictions have been wrong, so far. And the way that the theorised results of warming are always portrayed as negative is a joke. There are huge areas of the planet that might well benefit, or remain unaffected. But anyway, I personally don't give a toss about GW, while no effort is being made to tackle the real cause, which is overpopulation. The carbon footprint for the whole population of the Earth is about 5 tons per year per person. About 350 tons in a lifetime. That's what one condom could save. Forget windmills, start with free condoms, if you want to make a difference. Birth control methods free to everyone on Earth would save far more carbon than windmills and solar panels, and the effect would multiply down the generations. In the medieval warm period, around the year 1,000, there were about 370 million people on Earth. Now there are over 7,000 million. Or to put it another way, in my lifetime, it's gone from 2,500 million to 7,000 million and rising fast. There's your problem.

No. So what? Since Darwin's tree is an explanation of the past 3,000 plus million years of evolution, and applied biology is all about the present, then it's not surprising. I don't work in "applied biology" so that's not likely to happen anyway, and you are asking for a "practical" use. Darwin's tree is self evident once anyone with half a brain is given the outline of how evolution works. It's all about THEORY and UNDERSTANDING of the past. I can't think of a practical use for the big bang theory in applied physics. It's nowhere near as bleeding obvious as Darwin's tree, but it's still accepted Theory in physics. And like I said, it's a pointless observation. These things explain the past in a coherent logical and evidence based manner. We no longer have to invent superstitious stories about big ghostly men in the sky making everything in seven days. Increasing understanding IS a practical use, in my book, and to me, all of biology is applied biology, because biology's main application has always been to understand the living world. And there's been nothing in the history of biology to remotely match Darwin's origin of species in explaining and understanding that. Of course, Darwin's tree can't explain talking snakes and women made from ribs. Or people living to 1,000 years old, or how eating one apple curses the human race for the next six thousand years. It DOES explain why we find simpler fossils in older layers of the Earth though. Explains it all perfectly well. To anyone who actually WANTS to know.

Probably from eating fish, I would say. I wonder if they found any in the stools from vegans?

In Australia and other hot sunny countries, there is a bonus, in that the times that you want most energy for air conditioning coincides with the times that you can generate electricity from solar panels. You don't get the same bonus in more mixed climates, when you want power for heating, but the Sun isn't giving much. Wind can help to a certain extent to cover some of the gaps, but you still need nuclear or gas or the like to cover all of the gaps. Efficient economic storage is still the holy grail. I don't really understand the resistance to land-based wind turbines by residents. I like them. I like the look, and the noise is negligible. I think people in the UK automatically object because they are obsessed with their house prices. Even if THEY don't mind them, they think it will reduce the value of their property to others.

I wouldn't use plastic for any hot drinks. Not because I have information of chemical leakage, but because glass is easier to clean thoroughly and doesn't go soft. I re-use plastic cold water bottles filling them with tap or spring water. I don't think you get long term leakage of chemicals, it's probably first use that leaks, and that is tiny. Tap water is usually ok, it depends mainly on the pipes. The tap water where I live used to be bad till they replaced the pipes, now it seems good. I got used to drinking spring water from Malvern (famous springs) years ago when the pipes were bad, and still do out of habit. I get about 130 litres at a time from a stand pipe for free.

This is my recollection of the system. It's bound to be far more complicated than what I remember. 1) The energy route is fat - glycerol - glucose via the liver. It's then circulated to the body's cells via the blood. So no is the answer. 2) The glucose blood sugar is regulated with insulin, and is reacted with blood oxygen via haemoglobin in the body's cells giving off CO2 and H2O 3) CO2 and H2O as above 4) No 5) No. Not under healthy circumstances