Tuesday, February 12, 2013
Thursday, February 7, 2013
DNA as Data Storage-A Reality
Researchers at the EMBL-European Bioinformatics Institute (EMBL-EBI) have created a way to store data in the form of DNA – a material that lasts for tens of thousands of years. The new method, published January 23 in the journal Nature, makes it possible to store at least 100 million hours of high-definition video in about a cup of DNA.
There is a lot of digital
information in the world – about three zettabytes’ worth (that’s 3000 billion
billion bytes) – and the constant influx of new digital content poses a real
challenge for archivists. Hard disks are expensive and require a constant supply
of electricity, while even the best ‘no-power’ archiving materials such as
magnetic tape degrade within a decade. This is a growing problem in the life
sciences, where massive volumes of data – including DNA sequences – make up the
fabric of the scientific record.
"We already know
that DNA is a robust way to store information because we can extract it from
bones of woolly mammoths, which date back tens of thousands of years, and make
sense of it,” explains Nick Goldman of EMBL-EBI. “It’s also incredibly small,
dense and does not need any power for storage, so shipping and keeping it is
easy.”
Reading DNA is fairly
straightforward, but writing it has until now been a major hurdle to making DNA
storage a reality. There are two challenges: first, using current methods it is
only possible to manufacture DNA in short strings. Secondly, both writing and
reading DNA are prone to errors, particularly when the same DNA letter is
repeated. Nick Goldman and co-author Ewan Birney, Associate Director of
EMBL-EBI, set out to create a code that overcomes both problems.
“We knew we needed to
make a code using only short strings of DNA, and to do it in such a way that
creating a run of the same letter would be impossible. So we figured, let’s
break up the code into lots of overlapping fragments going in both directions,
with indexing information showing where each fragment belongs in the overall
code, and make a coding scheme that doesn't allow repeats. That way, you would
have to have the same error on four different fragments for it to fail – and
that would be very rare," says Ewan Birney.
The new method requires
synthesising DNA from the encoded information: enter Agilent Technologies, Inc,
a California-based company that volunteered its services. Ewan Birney and Nick
Goldman sent them encoded versions of: an .mp3 of Martin Luther King’s speech,
“I Have a Dream”; a .jpg photo of EMBL-EBI; a .pdf of Watson and Crick’s
seminal paper, “Molecular structure of nucleic acids”; a .txt file of all of
Shakespeare's sonnets; and a file that describes the encoding.
“We downloaded the files
from the Web and used them to synthesise hundreds of thousands of pieces of DNA
– the result looks like a tiny piece of dust,” explains Emily Leproust of
Agilent. Agilent mailed the sample to EMBL-EBI, where the researchers were able
to sequence the DNA and decode the files without errors.
“We’ve created a code
that's error tolerant using a molecular form we know will last in the right
conditions for 10 000 years, or possibly longer,” says Nick Goldman. “As long
as someone knows what the code is, you will be able to read it back if you have
a machine that can read DNA.”
Although there are many
practical aspects to solve, the inherent density and longevity of DNA makes it
an attractive storage medium. The next step for the researchers is to perfect
the coding scheme and explore practical aspects, paving the way for a
commercially viable DNA storage model.
How much data can you get in one gram of DNA?
Scientists from the European Bioinformatics
Institute are squeezing unparalleled amounts of data in to synthetic DNA, and
now they’ve achieved something absolutely amazing: they can store 2.2 petabytes of information in a single
gram of DNA, and recover it with 100 per cent accuracy.
The researchers have encoded an MP3 of
Martin Luther King’s 1963 “I have a dream” speech, along with all 154 of
Shakespeare’s sonnets, into a string of DNA. Scaled up, that represents a
storage density of 2.2 petabytes per gram. What’s amazing, though, is that
they’ve managed to achieve that whilst also implementing error correction in
the complex chains of molecules, allowing them to retrieve content with 100 per
cent accuracy.
The technique uses the four bases of DNA —
A, T, C and G — to achieve the high information density. It is, understandably,
still incredibly expensive: creating synthetic DNA and then sequencing it to
read off the data is getting far easier, but it’s still a time- and
cash-consuming business. Keep hold of your hard drives for now, but DNA could
represent a viable storage solution in the future.
Monday, February 4, 2013
10 Most Famous Diamonds In The World.
1. The Hope Diamond
The Hope Diamond is not only one of the most famous gems in the world, but it is also one of the largest blue diamonds (4th largest). It’s physical value might be estimated but it’s historical importance is priceless. It is so old that no one knows exactly when it was discovered. However, it already had an owner in 1668, in the person of an Indian slave who claimed that the 112 carats stone (which he believed to be a sapphire) came from the eye of an idol. Jean Baptiste Tavernier, a traveler and a gem merchant bought it and sold it afterwards to King Louis XIV of France. Its price today is estimated at $250 million. The legend says that this diamond was cursed by the Hindu priests of the temple from where it was stolen.
2. The Golden Jubilee
The Golden Jubilee is holding the title of the world’s largest faceted diamond in the world, measuring 545,67 carats. It was discovered in 1985, in the Premier mine of South Africa. At first, it was considered an ugly brown diamond. Gabriel Tolkowsky received the diamond, which was supposed to be used at testing some new tools and cutting methods. The result astonished everyone. It turned out that the “Unnamed Brown” was actually a very beautiful yellow-brown diamond. It remained unnamed until it was presented to the king of Thailand in 1997, for the 50th anniversary of his coronation (thus, its name).
3. The Cullinan I
One of the most famous diamonds in the world, Cullingam I was justly considered the largest diamond in the world up to the discovery of the Golden Jubilee. Also known as “The star of Africa”, the pear-shaped stone is the largest of the 9 diamonds cut from the largest rough diamond ever, the Cullinan diamond(3106,75 carats). Currently, it is the head of St. Edward’s scepter, one of the British Crown Jewels but it can be removed and worn as a brooch.
4. The Idol’s Eye
The idol’s eye is one of the most mysterious diamonds in the world. Its entire history is unknown; we have no idea where it came from, when it was discovered or who owned it. The only clue is its name, “The Idol’s Eye”. It appeared in a note, at Christie’s when it was described as a flawless large diamond. It was bought by an anonymous buyer and disappeared again for some years. Its owners changed several times afterwards and was bought in 1979 by Mr. Laurence Graff, who sold it again in 1983, to an anonymous buyer who is believed to own the diamond today.
5. The Spirit of de Grisogono
This is one of the famous diamonds in the world. It is also known as the largest cut black diamond, and it measures 312, 24carats. This beautiful diamond was named after the Swiss jeweler who cut it, using the old Mogul style. The result was the jewel you see in the picture and it is the work of an entire year. Currently, it is owned by a private client, who must be a very fortunate person.
6. Koh-I-Noor /Mountain of light
Apparently, this is one of the oldest diamonds known to man. According to the legend, this diamond is more than 2000 years old, from before the birth of Christ. However, a much more documented hypothesis is that it was discovered in the early 1300s. The earliest recorded mention of the diamond is in the memories of Babur (Baburnama), the first Mogul ruler of India. It then passed through many hands and its long, complex history cannot be told here.
It suffices to say that the diamond arrived to England in the 19th century and entered the possession of Queen Victoria. Not satisfied with its cutting, which caused it to shine less than it should have, the queen had it recut, which meant a loss of weight of almost 43%. It was then set in the queen’s crown,in frontal position. India did not give up one of its most precious gems easily. The Indian government continued to ask the return of the diamond, with no success.
It suffices to say that the diamond arrived to England in the 19th century and entered the possession of Queen Victoria. Not satisfied with its cutting, which caused it to shine less than it should have, the queen had it recut, which meant a loss of weight of almost 43%. It was then set in the queen’s crown,in frontal position. India did not give up one of its most precious gems easily. The Indian government continued to ask the return of the diamond, with no success.
7. The Orlov
The Orlov is one of the most intriguing diamonds in the world. It has a blurry past and it is said that it was stolen from an idol, where the stone stood as one of the eyes of the statue. However, many questions remain: First, if this is true, what happened to the other eye? Could it have been the above mentioned Koh-i-Noor? Another theory is that the Orlov diamond is actually the legendary stone called the Great Mogul, which was only described by Jean Baptiste Tavernier and it was lost forever centuries ago.
Whatever the truth, The Orlov diamond is now in the possession of the Russian government and it is set in the Imperial scepter. It is estimated at 189 carats but its historical value cannot be priced.
Whatever the truth, The Orlov diamond is now in the possession of the Russian government and it is set in the Imperial scepter. It is estimated at 189 carats but its historical value cannot be priced.
8. The Florentine
The Florentine is an enigmatic diamond which is believed to have a light yellow color, with a green overtone and an estimated 137 carats. Its known history starts with the duke of Burgundy in the 15th century. Apparently, he died in battle while wearing the diamond. The stone was stolen from him by a peasant who sold it for a florin, because he thought it was mere glass. It then changed owners several times, for small amounts of money. In the 17th century, we find the Florentine in the possession of the Medici familly. When the last Medici died, the diamond arrived in Vienna, and became one of the Habsburg Crown Jewels. After the World War I, it was stolen and never found again, though a particular diamond was believed to be the lost one, because of its similarities with the Florentine.
9. The Heart of Eternity
The diamond which bears such a romantic name is measuring 27,64 carats . It was found in a mine in South Africa and it has a “fancy vivid blue color”, making it an extremely rare diamond. Apparently, the blue color is given by impurities of boron and most of the gems are not entirely blue. The stone was an impressive 777 carats when found and caused a rush among diggers, who started to dig like crazy, trying to find another one. However, experts estimate that such a discovery is not likely to occur in the next several hundred years.
10. The Moussaieff Red
This gem is of an amazing beauty and it is estimated at 5, 11 carats. It has a triangular brilliant cut (it features numerous facets, which offer it great brilliance). Its amazing color was established to be “fancy red” by the Gemological Institute of America. One of the most famous diamonds in the world, the Moussaieff Red was first discovered by a Brazilian digger in the Abaetezinho River in 1990 and it is believed to have had 13.9 carats.
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