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Sunday, February 14, 2010

Do rockets punch holes in the ozone layer?


Do rockets punch holes in the ozone layer?

we know that the major culprit for making holes in the ozone layer are chemicals called CFCs — chloro-fluoro carbons. These are things that were used in aerosols, even in aspirin inhalers, but also in fridges as refrigerants, and they were used in huge amounts until the Montreal Treaty came in, in the late 80s to try and ban them. What provoked that was that a group of scientists including Brian Gardner had actually noticed this massive hole opening up over Antarctica in the mid-to-late 80s and this hole actually grew to be the size of Australia at its peak. It stopped growing; it’s actually beginning to shrink a little bit now and that’s because we have stopped using these chemicals. The reason that they concentrate down in the Antarctic is because the Antarctic is an isolated continent. It’s completely surrounded by ocean and this creates something called a circumpolar current, and this has a sort of whirlpool-like effect in terms of air; and it draws in and concentrates these molecules over the Antarctic over winter when it’s very dark. They then accumulate in high clouds over the Antarctic and when the sun comes out the following spring the sun breaks down the CFCs and they get turned into reactive chemicals that would then react with the ozone and deplete it. They are, by far, in a way the worst culprit. We don’t send enough rockets and spaceships up into space to make a huge difference, I wouldn’t have thought, in grand scheme of things. So I think although we have to be environmentally conscious, I think the benefit of sending rockets into space in terms of what they can do for satellites and furthering research is far greater than the small bit of damage they might make to the ozone layer. So I think on the whole, probably not, it’s probably more a man made, anthropogenic problem.


If you don't cut and /or wash your hair, does it grow any slower?


If you don't cut and /or wash your hair, does it grow any slower?

Unlike most other mammals, we have a very specific personal care and hygiene regime. Washing doesn't affect the hair growth itself except for some effect you may get from massaging the scalp as you are washing the hair by ensuring optimal blood circulation in the scalp, which may have some positive benefits for the hair follicle itself. Shaving does not impact on the quality of the actual hair fibre produced in that the hair is a dead entity above the surface of the skin.

There is a perception of thickened hair re-growth because if you were to cut it with a sharp instrument like a razor you would end up getting a sharpened end of the hair at its thickest point rather than that more fine, tapered end. Hair growth is very important for the success of the mammal and nature has provided enormous back-up systems to ensure that the hair continues to grow. In the wild you can imagine the loss of a coat would really be disastrous for a mammal in terms of regulations or camouflage etcetera. As a result the skin has invested enormous power into maintaining the hair follicle. That's why it's hard to grow when you want it to grow or stop growing when you want it to stop growing. That's because the principal driver for hair growth is hormonal, especially in those areas of the body with changed hair pattern after puberty.

There's a lot of clinical evidence to suggest that if you have abnormalities of the endocrine system or the hormone system you can have altered patterns of hair growth: either too much or too little.