| Subscribe via itunes,yahoo or google |
< Previous Show | Next Show > |
28th Jan 2007
Extreme Organisms and Hydrothermal Vents
|
|
This week we take a look at extreme environments and the organisms that live in them. Dr Crispin Little from the University of Leeds talks about hydrothermal vents and the fastest fossilisation on the planet, Professor Steve Scott from the University of Toronto explains why mining companies are interested in hydrothermal vents, and Dr Lisa Pratt from the University of Indiana describes how bacteria find energy three kilometres beneath the surface of the earth, and how similar strategies could be used by life on other planets. From the extremes of the Earth to the extremes of the kitchen, Derek Thorne and Hugh Hunt find out what's hot and what's not in the dishwasher...
|
|
|
|
|
|
|
News
Researchers in Australia are hopping with excitement having uncovered some of the most pristine fossils ever found in Australia, including 8 new species of kangaroo. The finds also tell a very different story of Australia in the past. Writing in this week's Nature, researcher Gavin Prideaux and his ...
This week, I published a paper based on research I did for my PhD, which looked at the growing trend for eating fish that have been collected from coral reefs all around the world and are flown to major Asian cities and cooked alive in luxury restaurants selling for extremely high prices. I found ou...

Scientists in the US have identified a coin-sized region of the brain responsible for nicotine addiction. Writing in this week's edition of Science, University of Iowa researcher Nasir Naqvi and his colleagues studied quit-rates amongst 69 smokers who had suffered strokes. 19 of the subjects had dam...
When the Wright Brothers flew the first ever aeroplane in 1903 it was seen as a masterful invention that would take humans into the skies, but in fact the idea of using biplane wings might have already been around for millions of years. Dinosaurs called microraptors lived in the Cretaceous Period ar...
Kitchen Science
If you've ever wondered why some plates dry quicker than others - this kitchen science is for you. This week Derek and Hugh Hunt are with Ali and Sandy, trying to investigate how we can purchase plates that speed up our washing cycle!
|
Interviews
Crispin Little has been studying the fastest fossilisation in the world at the bottom of the ocean
We look at bacteria found in the bottom of gold mines in South Africa
Steve Scott looks at mining useful mineral from the bottom of the ocean.
Questions

Why does 27 degree air feel hot but water of the same temperature feels cold?
That's to do with conduction. Water conducts heat much more readily than air so it's simply sucking heat out of your body, which makes you feel cold. If you think about wind chill, you can go out in the Antarctic and on a very still day which is minus 30 degrees you won't actually feel that cold. It's the movement of the wind past you that makes you cold. Those air molecules passing over you are each stealing a little bit of energy from the surface of your body and then moving on so you cool down much quicker. If you're wearing a wetsuit in water you have a single layer of water around you that warms up. Without a wetsuit the water is moving around you and robbing your body of energy all the time and cooling you down. This is why if you fall into cold water you should keep your clothes on and stay still and not swim around.

What causes my manure heap to heat up and steam?
It's all about bacteria breaking down organic waste into compost, that stuff you can put on your roses to make them grow nicely. Basically breaking down organic compounds generates heat in the process. It's similar to when our bodies metabolise things, these chemical reactions that are going on create heat. Mainly in our liver, which is a huge source of energy production in the body. A manure heap is a thriving community of microbes all producing heat and similar things happen in farmers hay bales which can get so hot they cause fires!

Why does stress cause palpitations and then anxiety or chest tightness?
When you're stressed, it initiates your body's fight or flight reaction, which is when you're preparing to do battle or run away from somebody. This pumps out loads of adrenaline, which causes your blood vessels and your heart to react. In order to get more blood to the rest of the body, the heart increases how hard it pumps and how fast it pumps, and what people are talking about when they say 'palpitation' is the feeling of your heart beating abnormally fast or hard. So it's all down to adrenaline, and it's also what causes panic attacks.

Is there a way that I can train myself in advance to avoid the risk of altitude sickness? I'm going to Tibet early in the year and I don't know how my body is going to react.
When you go up a mountain, there's less oxygen, and because there's less oxygen your body recognises this and starts to breathe a lot harder, so your rate of breathing goes up. Whilst this does increase the amount of oxygen in the blood, it decreases the amount of carbon dioxide stored in the blood. Carbon dioxide is a weak acid, and what this does is make your blood more alkaline, which is what makes you feel unwell. So that's why hyperventilating makes you feel dizzy because you lose carbon dioxide. There's a drug called acetazolamide, which is a carbonic anhydride inhibitor. How that works is that it stops your body converting the stored acid back into carbon dioxide, so it keeps your blood a little bit more acidic and you feel better. People in the Andes swear by cocaine or coca tea.

How do laptop mousepads and iPod scroll wheels work?
The pads are electrically sensitive to capacitance, or how much charge you can store in a certain area of the pad. When you put your finger on you need to have good electrical contact between your finger and the pad. Then it works out effectively how much charge is stored on that spot. It's got a matrix or array of wires running in one direction, and then the other direction. So it can literally use the x and y to work out where your finger must be. As you move your finger it's sensing how the stored charge moves across the pad. It resolves that into a direction and translates it into movement of the pointer on the screen.
|
|
|