Barcodes on way out?

A new product-tagging device has been revealed by Dr Ankit Mohan, a researcher at the Massachusetts Institute of Technology which may make the traditional barcode a thing of the past. The new device, being shown off at Siggraph, a conference in New Orleans next week has been called a 'bokode'.

The bokode has a diameter of 3mm and can hold thousands of times more information than a barcode. The powered device consists of a small LED behind a mask and a lens. The information is encoded into the light itself and can theoretically be read from distances of up 20m.

Developers say that the new device has many advantages over the standard barcode, including its small size, the ability to 'read' the light from many angles, and the fact that the information can be captured by a simple mobile phone camera.

The bokode will probably be introduced initially in an industrial warehouse setting, but could soon be hitting the high street where they could be used to encode nutritional information, or pricing offers.

There is also the potential for integration with applications such as Google Street View. If shops and restaurants had a bokode outside their premises, the Street View cameras would pick up the encoded information and this could then be displayed on Street View allowing users to see menus or special offers.

The tags are currently too expensive for widespread use at around $5 each, but developers hope to reduce the cost by eliminating the need for them to be powered by making them reflective. Previous attempts to replace the barcode have not succeeded, with radio-frequency tags only really taking off in library books and passports.

Ice to blame for pockmarked moon!

Everyone can see that the surface of the moon is scarred by craters and pits, but until now no one could say whether these were the result of rocky asteroid collisions or icy comet showers.

Although the earth and moon are both about 4.5 billion years old, these craters are only thought to date to the 'Late Heavy Bombardment' period, about 3.8 billion years ago. At this time it is thought that around 100 million billion tonnes of rock or ice crashed into the earth and sun. The earth has since recovered with plate tectonics removing any remaining surface damage.

Scientists have measured iridium levels in the oldest known rocks on earth to find out whether the Late Heavy Bombardment onslaught was indeed rock or ice. Iridium is rare on earth as it binds to iron, and long ago was mostly drawn into the earth's core. However, asteroids and comets are rich sources of iridium, with asteroids leaving more iridium on impact as comets lose more during space travel.

The amount of iridium found in the these ancient Greenland rocks is consistent with what would be expected from comet bombardments. And what's more, the amount of comet water that would have been expected to remain on the earth's surface following such an attack is equivalent to the total volume of the world's oceans, although no one really knows whether any water existed on our planet prior to the Late Heavy Bombardment period.

Intelligent Pills!

In the realm of pill-popping, a brave new world is today emerging with the news that scientists have developed intelligent tablets. Capsules have been created that have the ability to decide when and where to release their contents in the body.

Nanotechnology has been used to implant tiny nanoparticles into the drug capsules. These particles can be programmed to require two distinct conditions in order to release the capsule contents. Only when the two correct stimuli are detected do the particles generate the output signal required for 'payload' release.

Jeffrey Zink at the University of California hopes that this discovery may lead to more targeted treatments for cancer. The toxic anticancer drug could be delivered to a very precise site in the body, potentially sparing the patient from the devastating side effects and more effectively killing the cancer cells.

Previous attempts at 'smart' drug delivery have tried to create so-called logic gates from DNA, but this method is the first to create an AND logic gate that requires the presence of two specific stimuli for activation.

The drug molecules can be held in tiny pores on the surface of the nanoparticle, only being released in the presence of two specific conditions. One condition might unblock the pore, while the second condition causes movement within the pore to expel the drug contents. Both of these actions would be required for drug release.

Don't be tied down by electricity!

Scientists are today revealing to the world a new system for conducting electricity that does not rely on cables and wires. The new system allows electrical current to be passed from one object to another through the air, without any other object being affected.

Eric Giler, chief executive of US firm Witricity, showed mobile phones and televisions charging wirelessly at the TED Global conference in Oxford.

The system works by having a magnetic coil (housed in a ceiling or wall cavity) that is powered by mains electricity. This coil resonates at a specific frequency, transmitting electromagnetic waves through the air. These waves can then be picked up by another coil (for example inside a television or mobile phone) which is resonating at the same frequency. The electrical appliance can then run or recharge using this electrical energy which it has 'absorbed' from the air.

The device is safe because humans and most objects around us are not magnetic and the device uses low frequency, long wavelength energy, which is almost entirely magnetic.

Similar concepts have previously been explored by the nineteenth century American inventor Thomas Edison and physicist and engineer Nikola Tesla. The great thing about Witricity's concept though is that it does not require 'line-of-sight', unlike other companies attempts to achieve similar feats using lasers.

Don't Find Yourself in Hot Water!

Water repellent clothing has long been known to have a crucial weakness - the fabric is only resistant to cold water, and is easily penetrated by hot liquids. A way has now been found to enhance the properties of superhydrophobic materials to make them 'scald-resistant' as well.

Inspiration for water repellent materials has been taken in the past from waxy leaves such as the lotus leaf. A combination of the waxy water-hating coating and a spiky surface texture means that water droplets landing on the leaf retain their spherical shape and just roll off. However, hot water melts the waxy coating and water pools on the leaf, making the spiky surface ineffective.

Scientists have now discovered that although artificial lotus leaves without the waxy coating remain resistant to water at higher temperatures, between 40-85 degrees they gradually become more hydrophilic, attracting the water rather than repelling it. There are two reasons for this. Firstly, the hot water expels air trapped beneath the droplet within the spiky surface of the leaf. Secondly, hot water droplets have a much lower surface tension and are therefore more easily coaxed out of their 'roll-off' spherical shape, allowing puddling to take place.

Recent research in Hong Kong suggests that the way forward seems to be a move away from borrowing plant technology and towards using carbon nanotubes. By coating material in a combination of carbon nanotubes and Teflon, scientists have come up with a fabric that can resist water and other liquids up to the temperature of 75 degrees. The Teflon resists the heat and the nanotubes trap tiny pockets of air under the fluid droplets so that they can roll off more easily.

It is hoped that this fabric may be used in helping to prevent the thousands of scald injuries that occur each year, particularly affecting children and the elderly.

See the light - see the dust!

The Herschel Space Observatory has been sending its first images back to Earth. Even though the instruments are still being set up and are not fully operational, some stunning pictures have been returned, giving hope of even better to come.

The aim of this giant telescope is to find out more about how stars and galaxies form and evolve in the wilds of space. "We have some excellent images; they're not calibrated, but they look spectacular," said Dr Göran Pilbratt, ESA's Herschel project scientist. So with even better images to come, we should be getting a really detailed look at stellar life.

However, scientists have warned that the pictures Herschel produces won't be pretty images of space like those produced by Hubble, because Herschel is sensitive to long wave lengths of light instead of short wavelengths like its predecessors. This means that although the images might not look as beautiful, they will contain details not visible by telescopes like Hubble.

The details that are visible with Herschel's images are not apparent in visible light, so these are things that have really never been seen before. The first pictures returned show dusty clouds of gas that give rise to stars. The images are especially rich thanks to Herschel's 3.5m mirror.

The telescope will begin its routine work towards the end of this year, and is fit to operate through until 2013, when it's cooling system will no longer be functional.

Hear more about this project from one of the Imperial Physicists working on the Herschel project, Dr Dave Clements. He will be a guest on Short Science in the next couple of weeks.

Who's Your Daddy - She Is?

Researchers in the north of England are this week hailing their breakthrough in stem cell research. They have published results of their work in the journal Stem Cells and Development which describes their success in creating a rudimentary sperm cell from embryonic stem cells.

The team, led by Professor Karim Nayernia at the Northeast England Stem Cell Institute are the first in the world to claim the creation of a sperm cell from stem cells. Professor Nayernia is quick to point out that while this sperm cell may look and act like a sperm cell - it has a head and wagging tail, it is far from being a functional spermatozoa that could go on to fertilise a human egg.

However, this breakthrough has stirred up much anxiety and controversy. If this work were to be followed up and a fully functional sperm cell were developed, any number of possibilities might become reality. It would be possible to create a sperm cell from stem cells taken from a female embryo. At the extremes of possibility, this could lead to a woman's egg being fertilised from sperm developed from embryonic stem cells taken from her own embryo.

In this work though, sperm cells were developed only from male stem cells. Although they might provide hope for future fertility treatment, in earlier fertilisation experiments using mice, all the baby mice died shortly after birth. This technique would also be illegal in the UK.

The next step in this work is to try to develop sperm cells from stem cells in the skin. This would allow scientists to grow sperm cells in men who are infertile to try to understand what the problem is, giving hope that their fertility could then be restored using further treatment.

Lofty Raft Floats Above Trees

Scientists wishing to study the leafy canopies in forests around the world have until now found themselves having to climb the trees from the bottom. Now a revolutionary inflatable tree raft may provide them with easier access to this lofty habitat.

Photo Cleyet-Marrel

Dany Cleyet-Marrel, a French pilot, came up with the idea of an inflatable raft that could be lifted above the canopy and then lowered onto the treetops by a hot air balloon. He then teamed up with Per Lindstrand, a Swedish aeronautical expert to bring this idea to production.

Lindstrand Technologies first needed to create an airship big enough to lift the mighty 750kg raft and came up with the AS 300, which at 8,500 cubic metres is said to be the biggest airship in the world. The airship has also been used to carry the 'sledge' - a sort of inflatable gondola that can carry three people up to the canopy to collect samples and specimens.

The success of this invention has been marred by governmental intervention in some countries. It is thought that some governments may be unhappy that the airship will get very clear views of areas of potentially illicit deforestation.

Science for Starters: MRSA (Methicillin-Resistant Staphylococcus Aureus)

This hospital superbug is a strain of the common Staphylococcus aureus bacterium. It often lives on the human body without causing harm but when the body’s defences are
weakened, it may cause an infection.

Individually, the bacteria appear spherical (-coccus from the Greek kokkos, meaning ‘berry’ or ‘grain’), but they can arrange themselves in groups or colonies shaped like bunches of grapes (staphylo- from the Greek word staphyle, meaning ‘bunch of grapes’) and in laboratory culture appear yellowish (aureus from Latin meaning ‘golden’).

MRSA has developed a defence against penicillin-type antibiotics (it is methicillin-resistant). It produces an enzyme (called β-lactamase), which breaks down the crucial central structure of the drug, preventing it from killing the bacteria.

Hand wash only - our sheep are shrinking!

Research fresh out of Imperial College, London and published in the Science journal has confirmed that sheep are paradoxically shrinking in size. Classic evolutionary theory would suggest that sheep should actually increase in size over successive generations, as only the larger and stronger sheep survive and mature to reproductive age. However, wild Scottish Soay sheep on the island of Hirta in the St Kilda archipelago have been found to be shrinking over the years.



Soay sheep are the only living example of the small, primitive sheep which inhabited the British Isles before the coming of the Norsemen and Romans. Their name is derived from the island of Soay off the coast of Scotland.

The shrinking phenomenon was first reported in 2007, but has attracted much controversy. The Imperial researchers have used the island as a 'wild' laboratory - as there are only sheep and plants on the island. The team used data collected over 20 years, along with the 'Price Equation' which is used to predict evolutionary change in a single characteristic over time. By knowing how the sheep would have changed if they had followed this equation, they were able to rearrange the equation to show how different factors have influenced the actual size of the sheep. They found that the natural environment had a stronger effect on the sheep than evolutionary influence.



The team propose that climate change can, in part, explain why the sheep are getting smaller. Evolution would suggest that only the biggest, healthiest sheep would survive their first winter, when grass is scarce on the ground. With milder winters, there has been much more grass available to the sheep and therefore the smaller sheep are also able to survive their first winter.

In addition, it is known that younger sheep tend to give birth to smaller sheep. These two factors seem have to have overridden the effects of natural selection. Researchers are at the moment hesitant to turn their theory into a predictive tool for the future, so don't pin your hopes on pocket-sized sheep just yet!

Big Cat Tragically Larger Than Life

The Amur tiger, or Siberian Tiger as it is more commonly known has today been reported to be on the very cusp of extinction. This tiger is the largest of all species of big cat, and used to roam free across Northern China, the Korean Peninsula and southern Russia.

At the beginning of the last century there were more than nine subspecies of wild tigers with a total population of over 100 000 around the world. Since then the Javan, Bali and Caspian tigers have all become extinct as a direct result of human activity.

Over the last hundred years the Amur tiger has become endangered by expanding human settlements causing the loss of up to 90% of the tiger's natural habitat and poaching. The 1940s were a critical time for this species, with a mere 20-30 animals reported to be surviving in the wild.

Hollingsworth, John and Karen/USFWS
Since then a massive conservation programme and a strict ban on hunting have seen the species pull back from the brink of extinction. Over 500 of the tigers survive in the wild and in excess of 400 are living in captivity. But this isn't the good news that it seems.

Although numerically, the tiger species has made a remarkable comeback, the genetic health of the species is still in dire straits. A

new study published in Molecular Ecology has revealed that following analysis of DNA material in scat from the wild tigers, the genetic diversity of the whole population of over 500 tigers actually represents what would be expected in a population of just 35 animals. This is the lowest diversity ever recorded for a population of wild tigers.

The tigers appear to have two genetically distinct populations, and the analysis suggests that perhaps as few as three tigers have crossed from one population to the other. The two populations are physically separated by a corridor of development, and the only way to save the smaller of the two populations is to open up a corridor for the two groups to intermingle.

However, on a brighter note, the scientists did find evidence that genetic traits that have since been lost in the wild tigers have been preserved in the captive populations, meaning that the conservation effort may have actively preserved these traits from extinction.