Wednesday, 4 September 2013

Stem-Cell Science


Stem cells are cells which can become any cell type, like bone, muscle or hair. There are two types of stem cells, embryonic stem cells and adult stem cells1. Embryonic stem cells come from a fertilized egg, whereas adult stem cells are only found in some tissues to repair damage, like bone marrow1. Because stem cells can become any cell type, they are very important to science and medicine. For example, growing organs for transplant from the individual’s cells, this would resolve the problem of organ rejection2, however this is quite difficult. Furthermore, embryonic stem cells have ethical considerations, because they derive from fertilised human eggs3. Even though the egg would never develop in to a living person, many people oppose this research because they believe in life beginning at fertilization. So, while adult stem cells pose more challenges in producing a specific tissue, it is favourable to embryonic stem cells, but has only just become a feasible alternative4.


It has recently been announced that the first beating heart has been produced from adult stem cells5. This was achieved by using a mouse heart, removing the cells and using the remaining framework as a scaffold for the human stem cells to adhere. The cells are induced to develop into heart cells and after a few weeks it began to beat. This technology is a huge step forward, because the cells began to beat on their own. This technology could revolutionize heart transplants and replace pace makers by using a patch of healthy beating heart cells to repair the damage in the heart.



Being able to grow structured human tissue in this way is likely to revolutionize not just medicine but research as well, allowing for the accurate modelling of tissues for rare diseases. The latest advance was seen in the formation of brain tissue from stem cells6. Brain tissue is particularly difficult to obtain for some rare conditions as it cannot be removed before death and then often required the consent of the grieving family. Being able to successfully model the brain for specific diseases in this way means that drugs and treatments can be initially tested in culture to determine if they are targeting the desired cell types.


Stem cells can also resolve other problems, for example the ethical treatment of animals and producing animals for food. This month a burger was made solely from cow stem cells induced to become muscle tissue, this could hail the future of the meat industry7. Not only would it be ethical, as no cows would need to be slaughteres, but also it would address the environmental impact that meat production has, such as production of methane gas and increased demands for meat with reduced areas of countryside available for agriculture. Overall, it looks that stem cell technology is likely to revolutionize every aspect of our lives, with even the pope recognising the value and importance of adult stem cells in the future of our world3.


1. http://en.wikipedia.org/wiki/Stem_cell
2. http://www.bloomberg.com/news/2012-03-07/stem-cells-let-kidney-transplant-patients-skip-rejection-drugs-study-says.html
3.  http://www.abc.net.au/radionational/programs/scienceshow/vatican-award-for-stem-cell-research/4817348
4. http://www.sciencemag.org/content/316/5830/1422.2
5. http://www.newscientist.com/article/dn24042-mouse-heart-beats-again-thanks-to-human-stem-cells.html#.UiU2Xpyt9h0
6. http://www.nature.com/news/stem-cells-mimic-human-brain-1.13617
7. http://www.theguardian.com/science/2013/aug/05/lab-grown-hamburger-synthetic-meat

Tuesday, 27 August 2013

Pitch Patience


The pitch drop experiment is a long-term experiment measuring the flow of pitch over many years. The most famous version of the experiment was started in 1927 by Professor Thomas Parnell of the University of Queensland in Brisbane, Australia, demonstrating that some substances that appear to be solid are in fact very-high-viscosity fluids1. Pitch was heated and poured into a sealed funnel and allowed to settle. In 1930, the seal was cut to allow the pitch to start flowing. The duration of time between drops allows scientists to determine the viscosity of pitch is approximately 230 billion (2.3×1011) times that of water2.


This is recorded in Guinness World Records as the world's longest continuously running laboratory experiment, it is predicted that there is enough pitch in the funnel to allow it to continue for at least another hundred years3. This experiment is predated by only two other still-active scientific devices, the Oxford Electric Bell (1840) and the Beverly Clock (1864), but both have experienced interruptions. The experiment is monitored by a webcam (a livefeed can be viewed here) but technical problems prevented the November 2000 drop from being recorded. Professor John Mainstone died on 23 August 2013 following a stroke4. He was 78. A similar experiment started at Trinity College, Dublin in October 1944 dripped on July 11th, 2013, marking the first time a pitch drop was successfully filmed5.


This experiment has become so well known that it has even been an influence to art, where artist Julie Mecoli creates sculptures from substances similar to pitch like bitumen, which initially seems to act like a solid, but then can begin to slowly flow, transforming the sculpture. 

1. http://smp.uq.edu.au/content/pitch-drop-experiment
2. http://www.physics.uq.edu.au/physics_museum/pitchdrop.shtml
3. http://www.guinnessworldrecords.com/records-2000/longest-running-laboratory-experiment/
4. http://www.uq.edu.au/news/index.html?article=26612
5. http://www.tcd.ie/Physics/tar-experiment/

Wednesday, 3 July 2013

Magic Memorisation


Memorisation is a difficult thing, espceially when the items to be memorized are abstract, like a list of numbers or playing cards1. These are not things we find easy to relate to and are not very distinctive, however, we have a great memory for stories and for the world around us. For example, we can remember all of the destinctive landmarks and features on our journey home, but are unable to remember someone telephone number. But by linking the number, by making each number a distinct image, we can then build a memory palace by playing each object in order along the route and just go over it in our mind and recite the number back2. The trickiest part of this method is establishing a set of visual images that work for you and are strange and outragious enough to remember. Another way to do this is just make each image very distinctive and then link them together with the next image in the sequence, known as the mnemonic liking system3. Here is an example of one way to do it4


So to memories the phone number 0831577910 you could make up a story like.... 'floating around in outer space, a special race takes place, the octopus is standing on a stool, since he came 1st and was awarded a gold medal, the 7 dwarves came both second and 3rd, the cat also took part, but lost interest and instead went bowling.' it works on a very visual part of our memory which we find easier to recall than thinking of the numbers themselves. while we often use rote learning for things like telephone numbers, it takes a great deal of time to learn them and we only tend to remember a few that are most used. However, something like rote learning cannot be used to memorise something like the order of a pack of cards, simply because our short term memorie can only cope with around 7 items1, and this is trickier when it comes to cards, because its hard to visulise each one indervidualy and keep them distinct. Using the mnemonic liking system and each card has a distinct image and a story can be created. 


However, if you are more of a people person and interested in celebraties, then maybe the alternative system might work better for you5. This system, you take the card number and transform it into a letter of the alphabet (mostly in alphabetic order with a few exceptions) and then take the first letter of the suit. This would form the initials of a famous person. Then all you would need to do is remember that person and then use this to remember the card.



So, for the 7 of Clubs, it would be G.C, George Cloony. 8 of Spades, H.S, Homer Simpson. Maybe this could be George Cloony talking to Homer Simpson at a party or just watching the simpsons. Easy. 


1. http://en.wikipedia.org/wiki/Memory
2. http://en.wikipedia.org/wiki/Method_of_loci
3. http://en.wikipedia.org/wiki/Mnemonic_link_system
4. http://www.wikihow.com/Remember-Lists-of-Words-with-the-Memory-Trick
5. http://climbformemory.com/2010/06/08/how-to-memorize-a-deck-of-cards/