Forever young

rhamphotheca:

Immortal Flatworms Defy Age

by PhysOrg staff

The discovery, published in the , may shed light on the possibilities of alleviating ageing and age-related characteristics in .

Planarian worms have amazed scientists with their apparently limitless ability to regenerate. Researchers have been studying their ability to replace aged or damaged tissues and cells in a bid to understand the mechanisms underlying their .

Dr Aziz Aboobaker from the University’s School of Biology, said: “We’ve been studying two types of planarian worms; those that reproduce sexually, like us, and those that reproduce asexually, simply dividing in two. Both appear to regenerate indefinitely by growing new muscles, skin, guts and even entire brains over and over again…

(read more: PhysOrg)     (image: Eduard Sola | Wikipedia)

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Provided by University of Nottingham (news : web)

minecanary:

Langston’s ant

Langton’s ant is a two-dimensional Turing machine with a very simple set of rules but complicated emergent behavior. It was invented by Chris Langton in 1986 and runs on a square lattice of black and white cells. The universality of Langton’s ant was proven in 2000. The idea has been generalized in several different ways, such as turmites which add more colors and more states.

Squares on a plane are colored variously either black or white. We arbitrarily identify one square as the “ant”. The ant can travel in any of the four cardinal directions at each step it takes. The ant moves according to the rules below:

1. At a white square, turn 90° right, flip the color of the square, move forward one unit

2. At a black square, turn 90° left, flip the color of the square, move forward one unit

These simple rules lead to surprisingly complex behavior: after an initial period of apparently chaotic behavior, that lasts for about 10,000 steps (in the simplest case), the ant starts building a recurrent “highway” pattern of 104 steps that repeat indefinitely. All finite initial configurations tested eventually converge to the same repetitive pattern suggesting that the “highway” is an attractor of Langton’s ant, but no one has been able to prove that this is true for all such initial configurations. It is only known that the ant’s trajectory is always unbounded regardless of the initial configuration.

Before I met you I was quite content

and happy with my life

But then you came and introduced

an extension of my world

which I thought didn’t exist

And every time I enter this extended world

I find myself intrigued, amazed, awed

This extended world somehow revolves

around you.

You’re the center of it all

Just as the four inner planets revolve

around our Sun, in the Sol star system

and so do the four Jovian planets

As Newton’s law of universal gravitation states

The force which attracts me to you is

inversely proportional to the square

of the distance between us

Which is why I prefer to be near you

so the force of attraction between us

will be so much stronger

and so I can gravitate more towards you

The locus of points equidistant to a single point

me being part of those points,

and you being the single point

Which is why you’re at the center,

and I find myself circling around you.