Earthquake near a major city with death toll 'unprecedented in human history' a matter of time: Professor Iain Stewart

by: Anthony Marx / The Courier-Mail

• Mega-cities built on fault lines
• More people living in danger areas
• Amazing map: A century of earthquakes

IT'S only a matter of time before a huge earthquake strikes a major city and results in a death toll "unprecedented in human history".

Well-known Scottish scientist Iain Stewart delivered that grim prediction yesterday in Brisbane during an address to a global geology conference.

Professor Stewart, a geologist and academic who has gained fame for multiple BBC television series on the planet, said the risk of disaster has grown because a growing number of mega-cities are built on or near major earthquake faults.

Large settlements since antiquity have been based on these fault lines because they also help provide water and are usually located near flat plains ideally suited for growing crops.

This "fatal attraction" to dangerous areas was "actually a good thing", because historically the trade-off was worth it since earthquakes were rare and most cities were not that large, he said.

While earthquakes today were often less destructive because of improved building codes, more people were affected because cities were larger, Prof Stewart told delegates at the 34th International Geological Congress.

Despite the danger of such hazards, people were still drawn to earthquake-prone California and the US gulf states, which were routinely hit by hurricanes.

Although it might seem that the number of natural disasters around the world is increasing, there are simply more people living in harm's way, and that fact creates the illusion. "We create the template that brings these disasters," Prof Stewart said.

Similarly, people want to live only 20m from the beach, even in regions liable to be struck by tsunamis. Even after properties have been destroyed, many owners vow to rebuild.

Further research was needed to understand why people continued to have such a high threshold for living in danger zones and why they often chose to ignore the science that could save their lives, he said.

Scientists create robotic skin so sensitive that it can feel the gentle patter of ladybirds walking across its surface

By Eddie Wrenn

Artificial skin could soon be created which could be sensitive enough to feel the steps of a lady-bird, or for the cruel-hearted, the stretching and tearing of a Chinese burn.

Engineers at Seoul National University are working on a prototype 'flexible electronic sensor', which uses interlocks hairs which can sense objects through static attraction.

The breakthrough - which was based on research into natural hairs on a beetle's back - could mean artificial limbs could be made to be more sensitive.

The artificial hairs are created from polymer fibres - tiny sheets of material is just 100 nanometres in diametre and a micrometre (one millionth of a metre) in length.

While invisible to the human hair, their tiny size and shape, and their metallic covering which makes them conductive to electricity, all combine to allow highly-sensitive readings.

Some of the potential uses for the skin includes using it as a heart monitor, which can be strapped to the wrist to detect your pulse.

Indeed the artificial skin can pick up brief touches which would not be detectable to humans - touches with a force of just five pascals can be 'felt' by the hairs.

The hairs can detect 'pressure', for instance a weight landing on the on the sheet, 'shear', such as an object sliding across the surface, and the twisting motion, like you might associate with that cruel and childish Chinese burn.

These final two movements are traditionally hard for mechanical objects to detect, but thanks to the electrical, microscopic hairs, the different signals can now be decoded.

The team has tested the pads by bouncing water droplets on the surface and testing out pule detection.
And in perhaps the cutest experiment in the history of science, they got a pair of ladybirds to walk across its surface.

VIDEO: Watch parts of the experiment, including the water droplet test!... 

Artifical jellyfish created in lab from rat cells

An artificial jellyfish which is able to swim with the help of beating heart muscle cells has been created by scientists.

By Nick Collins, Science Correspondent

The tentacled artificial creature, made from silicon, has been dubbed "Medusoid" because of its resemblance to the snake-haired character from Greek mythology whose gaze turned people to stone.

It is able to mimic the swimming movement of a jellyfish thanks to muscle cells from rat hearts which were implanted onto its silicon frame and grown into a pattern similar to the muscles of a real jellyfish.

By applying an electric current to a container of conducting liquid, the scientists demonstrated they could "shock" the muscles into contracting so that it began to move through the water.

The "reverse-engineering" project by researchers from the California Institute of Technology and Harvard University was published on the website of the Nature Biotechnology journal.

Janna Nawroth, lead author of the study, said that most researchers working in tissue engineering have attempted to copy tissue or organs by simply recreating its major components, regardless of what their function is and whether they could be replaced by something simpler.

She said: "A big goal of our study was to advance tissue engineering. Our idea was that we would make jellyfish functions — swimming and creating feeding currents — as our target and then build a structure based on that information."

Her colleague Prof John Dabiri added: "I'm pleasantly surprised at how close we are getting to matching the natural biological performance, but also that we're seeing ways in which we can probably improve on that natural performance. The process of evolution missed a lot of good solutions."

Jellyfish use a pumping muscle to propel themselves through the water, meaning their movement is based on a mechanism similar to a human heart.

This makes them a useful model for tissue engineering, technology which could one day be used to create synthetic hearts or other organs for human patients.

Prof Kevin Kit Parker, one of the study's authors, said: "I saw a jellyfish at the New England Aquarium, and I immediately noted both similarities and differences between how the jellyfish pumps and the human heart. The similarities help reveal what you need to do to design a bio-inspired pump.

"The jellyfish provides a design algorithm for reverse engineering an organ's function."

Prof Dabiri added: "A lot of work these days is done to engineer molecules, but there is much less effort to engineer organisms.

"I think this is a good glimpse into the future of re-engineering entire organisms for the purposes of advancing biomedical technology."