You will hear a talk on research in nanotechnology.
First, you have some time to look at questions 31 to 40.
Now, listen carefully and answer questions 31 to 40.
Welcome to the second lecture in our series on modern technology.
Today, I'll be discussing the recent developments in nanotechnology, in addition to its applications in a number of environments, such as domestic and medical.
First of all, I'd like to begin with a short explanation of what nanotechnology is.
It is the manipulation of matter on an atomic, molecular and supermolecular scale.
Because of its limitless applications and uses, the government has invested billions of dollars into the research and development of nanotechnology in order to explore its potential.
It is only recently that we have been able to engage in the development of nanotechnology, since some particles are so minuscule that a new type of microscope had to be invented to enable us to see them.
Many of you may not realise that we all use nanotechnology in our homes as a part of our daily lives.
For example, a new dietary supplement uses nanotechnology in order to help our body to absorb iron from our diet more efficiently, which can help to prevent anaemia.
This technology also makes it easier and cheaper for factories to produce foods such as chocolates, as the nanomolecules help the food to meet our recommended daily intake of certain vitamins and minerals.
This may sound odd, but in fact it just means that the food is healthier and cheaper and has increased flavour.
Another application for nanotechnology is in the agriculture industry.
In the past, farmers have been using many artificial chemicals to fertilise the soil, which is extremely bad for the planet as it contaminates the water that we drink.
By using nanotechnology, scientists have been able to develop a spray, which increases the efficiency of fertilisers that occur naturally in the soil.
This means that a lot more food can now be produced per square hectare, making it cheaper and more efficient to grow without harming the planet.
One of the industries upon which nanotechnology has had the biggest impact is the production of pharmaceuticals.
One of the most commonly occurring illnesses is food poisoning, as many foods have naturally occurring contaminants that can be harmful if eaten without being thoroughly cooked.
Nanotechnology makes it possible for us to sterilise the food and make it safe to eat by killing these bacteria.
A major success in the use of nanotechnology in the medical field is in the treatment of cancer.
Researchers have found that they can attach medicine to nanoparticles, which are then injected into the body and enable the therapeutic drugs to be absorbed into the veins.
These drugs then travel throughout the blood system and target cancerous tumours.
Scientists have also discovered that certain metals contain nanoparticles that have antibacterial qualities with the ability to destroy over 650 types of bacteria.
These metals are used, for example, on fridges to prevent the growth of bacteria.
They can even be woven into materials to create clothing that is self-cleaning and has an attractive metallic appearance.
The most popular of these materials contains silver, which naturally has the strongest antibacterial qualities.
These clothes have a special tag on them to show that they use nanotechnology, so keep a look out for them next time you go shopping.
Another observation made by some researchers showed that certain types of nanoparticles called spliferines can destroy fat tissues and therefore stimulate fat loss without the need for dieting or exercise.
They are currently developing a supplement that can be ingested in order to help dieters with their weight loss programmes.
It is predicted that these supplements will be on the market by 2020.
I would like to finish today's lecture with a final example of a domestic application for nanotechnology – cosmetics.
Nanoparticles are used in many make-ups and body lotions, but they have the greatest effect in sun cream.
Ultraviolet rays given off by the sun are a serious cause of skin cancer, but the nanoparticles in sun cream protect the skin against the sun by blocking the ultraviolet radiation from entering the body.
This is why you must always wear suntan lotion on the beach.
Now I'd be happy to answer any questions you may have.
That is the end of section 4.
You now have half a minute to check your answers.
That is the end of the listening test.
In the IELTS test, you will now have 10 minutes to transfer your answers to the answer sheet.
