Innovation and Technology Weekly – No. 15, 2011

This is the online version of UNU-MERIT’s I&T Weekly which is sent out by email every Friday. If you wish to subscribe to this free service, please submit your email address in the box to the right.

Issue 15, 2011

This week's headlines:

Scientists manipulate mosquitoes in malaria fight
April 20, 2011

Scientists working on malaria have found a way of genetically manipulating large populations of mosquitoes that could eventually dramatically reduce the spread of the deadly disease.

Researchers from Imperial College London and the University of Washington found that after making specific genetic changes to a few mosquitoes and then allowing them to breed on, genetic alterations could be spread through large mosquito populations in a few generations. This is the first successful proof-of-principle experiment of its kind and suggests the method may in future be used to spread genetic changes in wild mosquito populations to make them less able to transmit malaria.

The scientists showed that a modified genetic element - a homing endonuclease gene called I-SceI - can efficiently spread through caged populations of mosquitoes. The genetic element 'homes' to a particular portion of the DNA where it becomes integrated into the broken chromosome. This process - known as genetic drive - could be used to transmit a genetic change through a population of mosquitoes that affects the insects' ability to carry malaria.

The team bred mosquitoes with a green fluorescent gene as a marker. They allowed these insects to mate with a small number of mosquitoes that carried a segment of DNA coding for an enzyme which can permanently inactivate the fluorescent gene. After each generation, they counted how many still had a green gene. The results showed that after starting with almost 99%t of fluorescent mosquitoes, more than half had lost their green genes in just 12 generations.

Full story: Reuters Back to top

Chance discovery may revolutionise hydrogen production
April 14, 2011

Producing hydrogen in a sustainable way is a challenge and production costs are too high. But now a team at Ecole Polytechnique Federale de Lausanne (EPFL) have discovered by chance that a molybdenum based catalyst can be produced cheaply and efficiently at room temperature.

Water can be broken down by applying an electrical current in a process known as electrolysis to produce hydrogen and oxygen. In order to improve this slow reaction, platinum is generally used as a catalyst. However, platinum is an expensive material that has tripled in price over the last decade. Now EPFL scientists have shown that amorphous molybdenum sulphides, abundantly available, make efficient catalysts and hydrogen production costs can be significantly lowered.

The new catalysts exhibit many advantageous technical characteristics. They are stable and compatible with acidic, neutral or basic conditions in water. Also, the rate of the hydrogen production is faster than other catalysts. The discovery opens up some interesting possibilities for industrial applications such as in the area of solar energy storage.

The next stage is to create a prototype that can help to improve sunlight-driven hydrogen production. But a better understanding of the observed phenomenon is also required in order to optimize the catalysts.

Full story: PhysOrg / EPFL Back to top

Apple iPhone stores data on users' whereabouts
April 20, 2011

The Apple iPhone might be storing detailed information about users' whereabouts and uploading it to their computers when they synchronize their digital devices, say two British security researchers. A program on the smartphone records geographic co-ordinates and a time stamp, which are then uploaded to a user's hard drive, meaning anyone with access to that drive could determine where a person has been and when.

Pete Warden and co-researcher Alasdair Allan, announced their discovery at the Where 2.0 technology conference in Santa Clara on Wednesday. Allan and Warden have set up a website detailing how the information is recorded, where it can be found and steps that can be taken to protect the information, including encrypting the data. In a blog post on Radar O'Reilly, a technology website, they said the data collection feature seems to have first appeared with the release of iOS 4 in June 2010.

Allan and Wardan say the data is not transmitted anywhere else but is normally stored in an unprotected format. It is also transferred to a new Apple phone when that device is synched up with the computer.

'We're not sure why Apple is gathering this data, but it's clearly intentional, as the database is being restored across backups and even device migrations,' they wrote. Attempts to contact Apple were not successful, and the company has not issued a statement about the claims.

Full story: CBC News Back to top

Self-healing plastic fixed with a laser's light touch
April 20, 2011

Researchers from the US Army Research Lab in Maryland, Case Western Reserve University in Cleveland and the University of Fribourg in Switzerland are reporting this week that they can fix cracks in materials with a flash of light.

Engineers have initially performed their trick using a special class of rubber called a metallo-supramolecular polymer. Unlike regular polymers like the polystyrene, or the clear polycarbonate that CDs are pressed with, the molecules in the new rubbery polymers are not linked by strong covalent bonds - which involve atoms sharing electrons. Instead, the spaghetti-like base units of the materials terminate in 'ligand' groups that like to link to free zinc based groups through ionic bonding. When UV light hits these zinc groups, they absorb energy and convert it into heat, which can be used for self-repair.

The team took a 0.4 mm-thick sheet of the polymer and gouged fissures between 0.2 and 0.3 mm deep in it. They then fired a 1 watt UV laser at each crack for 30 seconds - and found the fissure healed completely. They now want to try healing a wide range of different polymers using lasers - but they have to be careful about the mixture. 'Materials with higher metal content healed less well,' they reported.

Full story: New Scientist / Nature Back to top

Cooling with heat
April 19, 2011

A quantum system can be cooled with a blast of hot incoherent light. That is the surprising conclusion of theoretical physicists who have shown that the rate of cooling can sometimes be increased by putting a system in contact with a hot entity.

Since the 1980s physicists have been cooling gases of atoms using coherent laser light. This method works by having atoms absorbing and emitting photons such that the atoms gradually lose momentum. This technique only works if the light is coherent - if it is not coherent the light simply heats up the gas. But now researchers of the Freie Universitaet Berlin have come up with a way of using incoherent light to cool a quantum system. Their system is a mechanical quantum oscillator that is coupled to two optical modes - but can be applied to a wide range of three mode quantum systems.

The process begins with the mechanical oscillator in a high-energy or hot state. One of the optical modes is cold, which means that energy can potentially flow from the oscillator to the cold mode - cooling the oscillator. The second optical mode is hot, meaning that it contains a large number of incoherent photons and is subject to thermal fluctuations. According to the team's calculations, this hot mode has two effects on the temperature of the mechanical oscillator. One effect is obvious; the hot mode heats the oscillator. The second unexpected effect is that fluctuations in the hot mode increase the rate at which energy is transferred from the oscillator to the cold mode. The key to a practical application is to ensure that the latter effect is dominant.

Full story: PhysicsWorld Back to top

DARPA takes new look at electrical brain stimulation
April 21, 2011

New research going on in Albequerque, NM by a team of neuroscientists working for the Defense Advanced Research Projects Agency (DARPA) indicates that mild brain stimulation with electrical shocks, might in fact cause people to learn more easily.

The team has been applying electrodes to the scalps of volunteers, and then giving them very mild electrical shocks while they play a battle simulation video game designed to teach soldiers to react properly in stressful conditions. Called transcranial direct-current stimulation (tDCS), the procedure employs a nine volt battery and electrodes connected to wet sponges affixed to the temples of game players to send just a few milliamps of current through the skull and into the brain as they attempt to differentiate between friend and foe in dilapidated, potentially dangerous environmental conditions.

Two groups were tested, one received 2 milliamps while they played, the other just 0.1. The volunteers receiving the larger amount showed twice as much improvement as those that did not. Because the amount of current is so small, volunteers report no pain, just a slight tingling sensation during the procedure, and afterwards can offer no real explanations as to why they performed better than they might have otherwise.

Full story: Medicalxpress / PhysOrg Back to top