West Herts Drive Time Science Correspondent 28/04/2014
Longest experiment yields ninth result
An experiment that has been running since 1927, recognised by the Guinness World Record as the longest-running laboratory experiment, has recorded its ninth data point. The experiment is a funnel full of a material known as pitch, which is a viscoelastic, semi-solid polymer. In the past, this material has been used to waterproof and seal seams on wooden boats and other wooden containers. As a highly viscous material, it is hard enough to be hit with a hammer causing it to shatter but under pressure it is able to flow like a liquid, even it is very slowly.
Scientists at the University of Queensland in Australia have been watching the experiment for 87 years. It was originally set up to show students that materials that appear solid can flow like liquids. Some pitch was put into a funnel and allowed to drip into a beaker below. In Dec 1938 the 1st drop fell; the 2nd drop was in February 1947; the 3rd was in April 1954; the 4th, in May 1962; the 5th, August 1970; the 6th, April 1979; the 7th, July 1988; and the 8th dropped in November 2000.
The most recent and ninth drop was on 17th April. Physicist John Mainstone dedicated his time to watching the experiment for drops to occur. He managed to miss all three drops that happened during his custodianship. In 1977, he spent the entire weekend watching it, but missed the drop when he went home exhausted. In 1988, he missed the drop when he went to make a cup of tea. In 2000, by when a webcam had been set up to monitor the experiment, he missed it due a 20 minute power cut due to a tropical storm. Sadly, Professor Mainstone died in August last year. This time due to recording footage of the experiment, the drop has been seen to occur for the first time.
Australia is moving north by six centimetres a year due to continental drift, this experiment moves 10 times slower than that. By the seventh drop, it was possible to calculate the viscosity of pitch as 230 billion times that of water. Common day-to-day viscous materials include toothpaste and tomato purée.
Laser eye surgery for the ears
Other species in the animal kingdom such as fish and birds can regenerate the hair cells in their inner ear over time, but mammals do not have this ability. Over time as we age hearing sensitivity can decrease; or other damage can occur to the inner and outer hair cells – loud noises, some antibiotics and diseases. At present we can only artificially mimic what the ear does to improve hearing loss. Hearing aids amplify sounds and cochlea implants transform sound waves into electrical frequencies so subtleties in voices and music can difficult to differentiate between.
A trial is about to go ahead to test whether results seen in mice can be replicated in humans without any long-term side effects. The mice, which had almost all of their ear hair cells destroyed, had a harmless virus injected into their cochlea and two months later they were able to hear significantly more, around 20 decibels. This is about equivalent to the difference in your hearing normally and holding your hands over your ears.
The team at the University of Kansas Medical Center, lead by Hinrich Staecker are hoping that the only side effect will be short-term dizziness and nausea, which are common after ear surgery anyway. This treatment, if successful, won’t be aiding hearing it will be repairing the ear and restoring the natural hearing processes. They will soon be recruiting volunteers for the study between the ages of 18 and 70; looking for people presently with severe hearing loss, as a risk is that residual hearing could be affected.
It is believed that the approach could help 1 to 2 % of people with hearing loss. The viral gene package will also be directly injected into the volunteers’ cochlea, and once the gene reaches the supporting cells, it instructs them to divide and form new hair cells, with results expected between two weeks and two months later. Tests have been performed to check whether the virus spreads to any other tissue, but it appears to be restricted to the site of injection.
As a laser is used in the process to allow access past the ear drum perhaps if this treatment is successful, we will be seeing adverts on TV for laser ear surgery in the future.
Scientist of the Month
Edward Jenner (1794 – 1823)
He contributed to the fields of medicine, surgery and natural history. He is most well known for his contribution to the development of vaccination and is known as the “father of immunology”.
He apprenticed in surgery and anatomy under surgeon John Hunter at St George’s Hospital in London. He eventually moved back to the countryside where he grew up and became a family doctor and surgeon.
In natural history, combining observation, experiment and dissection, he studied the cuckoo and found, contrary to belief that it is the cuckoo hatchlings that push the eggs and hatchling birds out of the nest, not the adult cuckoos. He discovered that the baby cuckoos have a depression in its back for the first 12 days of its life in order to cup the eggs and other chicks native to the nest and uses that to push them out.
He advanced the understanding of the heart condition angina.
Smallpox was a common disease at the time and Jenner noticed that milkmaids seemed to be more generally immune to smallpox and he hypothesed that they were protected from smallpox after having been infected and survived a bout of cowpox. Cowpox is similar, but much milder than the highly contagious and often lethal smallpox.
Jenner purposely infected the son of his gardener with cowpox, giving him symptoms including a fever and uneasiness, but not a full infection. He later injected him with smallpox but no disease followed. He injected the boy a second time, but again with no sign of infection. He had created an immunity to smallpox without people having to be inoculated with smallpox, which was the current method where material taken from someone who had recently had smallpox and hoping the person inoculated with that material only suffered a mild form of smallpox.
Jenner’s method proved much more effective and less dangerous than the previous method and has led to smallpox being declared an eradicated disease in 1979 by the World Health Organisation.
He has a crater named after him on the Moon.
Night Sky This Month
Jupiter is still high in the sky and makes for excellent observing, even though it is passed opposition. The Great Red Spot (a storm that has been raging for at least 300 years) has become more prominent and perhaps can even be viewed in a small telescope.
Mars has reached opposition this month so from now on will be getting smaller in angular size, making viewing surface features harder. With a small telescope and good seeing it should be possible to make out the northern polar cap and Syrtis Major – dark, triangular shaped region.
The crater named after Edward Jenner, the “father of immunology” is on the south eastern edge of the Moon as viewed from Earth in the region known as Mare Australe and can sometimes be seen when the Moon slightly wobbles on its axis in the right direction.
The constellation of Leo prominent in the night sky currently and has several Messier galaxies and at the base of the lion’s neck, a double star or binary system called Algieba which can be viewed with a telescope.