Friday, August 31, 2012

Goby fish and Gondwanaland

My bookmark 
 An educational and interesting article on ancient fish and continental drift by Jonathan Ball BBC News 31 August 2012 

Eyeless goby fish 10.000 km apart share common ancestor

Wednesday, August 29, 2012

Military scientists learning from God

Dr Denis Spitzer from the military oriented Institut Franco-Allemand de Recherches de Saint-Louis calls it bioinspiration rathern than biomimicry!
...That's the vision of scientists who work on electronic noses, and now, thanks to the silkmoth, the world's most sensitive electronic nose for explosives was recently demonstrated in the lab. One thousand times more sensitive than comparable devices, it consists of a tiny, vibrating cantilever coated in a forest of titanium dioxide nanotubes that were inspired by similar structures on the antennae of silkmoths.

"For me, this is bioinspiration, not biomimicry," says Spitzer. The moth detects molecules through a "lock and key" system in which individual molecules are caught by smell sensor receptors, which then activate neurons connected to the animal's brain. Spitzer's system works by a very different mechanism, but this insight from the physical structure of the moth's antennae proved to be a crucial one.
Christopher Mims
Read the entire article in BBC Future - Technology 29.8.2012

Tuesday, August 21, 2012

DNA and family trees - Yan Wong

Bang Goes The Theory ! BBC Dr Yan Wong
Dr Yan Wong is an evolutionary biologist specialising in computer and mathematical modelling of evolutionary genetics. He is a presenter of the BBC One science programme Bang Goes The Theory and a contributor to More or Less.

Following excerpts are quoted from a highly interesting article on evolutionary genetics by Yan Wong.

Just like a surname, or the male lines of descent quoted in the Bible, these generate lineages that shrink or expand rather slowly. That's why we expect the proportion of Smiths in the phone-book to fluctuate only a little from decade to decade.

The surprise comes if we look at inheritance from both parents. Here, the numbers change drastically as the generations go by. For instance, we have two parents, four grandparents, eight great-grandparents, and so on.

Each generation back, we multiply the number by two. This leads to what is called an exponential increase: 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024 and so on.

It's not long before we hit huge numbers. Take the specific case of Jesus and King David.

The number of generations between them is at least 35. Luke lists 42 generations down the male line, and Matthew gives an incomplete list of 27.

These numbers agree reasonably well with an average time between generations of 25 or 30 years - an estimate taken from documented historical records from Iceland and Canada.

So back in the time of David, Jesus would have had at least 2 x 2 x 2 x 2 (35 times); in other words 2^35 - or more than 34 billion potential ancestors. That's far more than the total population of the world, of course.

This is a good illustration of what's been called the "genealogical paradox".

Adam and Eve again!
How far do we have to go back to find the most recent common ancestor of all humans alive today? Again, estimates are remarkably short. Even taking account of distant isolation and local inbreeding, the quoted figures are 100 or so generations in the past: a mere 3,000 years ago.

And one can, of course, project this model into the future, too. The maths tells us that in 3,000 years someone alive today will be the common ancestor of all humanity.

A few thousand years after that, 80% of us (those who leave children who in turn leave children, and so on) will be ancestors of all humanity. What an inheritance!

Yan Wong
Read the entire article in the BBC magazine

DNA wrapping - a WEHI movie

Uploaded to youTube by WEHImovies on 23 Nov 2010

"These DNA molecular visualizations were created for the multifaceted 'DNA' project, celebrating the 50th anniversary in 2003 of the discovery of the double helix. The 'DNA' project includes a five-part documentary series, museum film and 'DNAi' online resources for teachers and students."

"The dynamics and molecular shapes were based on X-ray crystallographic models and other published scientific data sets. Leading scientists, including many Nobel Laureates, critiqued the animations during their development. Particular effort was made to ensure the relative shapes, sizes and 'real-time' dynamics were as accurate as possible."

Walter and Eliza Hall Institute of Medical Research

Friday, August 17, 2012

DNA storage - Harvard learning from our Creator!

Harvard cracks DNA storage, crams 700 terabytes of data into a single gram

A bioengineer and geneticist at Harvard’s Wyss Institute have successfully stored 5.5 petabits of data — around 700 terabytes — in a single gram of DNA, smashing the previous DNA data density record by a thousand times.

The work, carried out by George Church and Sri Kosuri, basically treats DNA as just another digital storage device. Instead of binary data being encoded as magnetic regions on a hard drive platter, strands of DNA that store 96 bits are synthesized, with each of the bases (TGAC) representing a binary value (T and G = 1, A and C = 0).

To read the data stored in DNA, you simply sequence it — just as if you were sequencing the human genome — and convert each of the TGAC bases back into binary. To aid with sequencing, each strand of DNA has a 19-bit address block at the start (the red bits in the image below) — so a whole vat of DNA can be sequenced out of order, and then sorted into usable data using the addresses.
Read the entire article by Sebastian Anthony from Extreme Tech website

The DNA storage system described in the quoted article can put in one gram the amount of binary data that would weight 151 kilograms in standard hard disks!

This is a classic case of us humans learning from God's wisdom and applying His genious into our own devices and procedures. Note, however, that George Church and Sri Kosuri simplify the DNA system by reducing the extremely complicated TGAC coding to simple Boolean by TG=1 and AC=0.

One day we probably know how to handle mathematically and physically full four digit coding and come closer to the model set by God of Israel who designed DNA.