2011 – A look back (part 4)

Nanotechnology

2011 was another big (or should that be small?) year for nanotech. In January, a team of Swiss researchers published a groundbreaking study. This revealed that Molybdenite – a mineral abundant in nature – could be 100,000 times more energy efficient than silicon transistors. It was also discovered to have better electrical properties than graphene. This material, which is also less voluminous than silicon, could have major potential in the fabrication of nanoelectronics, LEDs and solar cells.

A major breakthrough in nanomedicine was achieved by scientists in Canada. Using a magnetic resonance imaging (MRI) system, they successfully guided microcarriers loaded with an anti-cancer drug through the bloodstream of a rabbit – directly to a targeted area in the liver, where the drug was successfully administered.

Progress was also made in developing “lab-on-a-chip” technology. In the future, this will enable rapid, portable and ultra-sensitive diagnosis of diseases and other conditions. It could also have uses in monitoring and testing of the environment. One such device, being developed at the University of California, can detect blood components at a concentration of around 1 part per 40 billion, within 10 minutes. Benjamin Ross, a study co-author, commented: “Imagine if you had something as cheap and easy to use as a pregnancy test, but could quickly diagnose HIV and TB. That would be a real game-changer. It could save millions of lives.”

At the University of Michigan, scientists made biodegradable polymers that could self-assemble into hollow, nanofibre spheres. These were filled with cells and injected into wounds – forming a support structure for the cells as they grew. Once the cells were held in place, the spheres dissolved harmlessly. During testing, the nanofibre group regenerated three to four times more tissue than the control group. In the future, this new method could dramatically improve the healing of cartilage and joints, by enabling complex and oddly-shaped tissue defects to be corrected.

At UCLA, scientists used nanoscale capsules to release a protein directly into lung cancer tumors, stimulating the immune system and causing it to recognise and attack the cancerous cells, inhibiting their growth. So far, the nanocapsules have only been tested in mice, but human trials are expected within three years. This new method, if successful, could allow cancers to be detected and treated at much earlier stages.

At the University of Southern California, researchers developed a carbon nanotube synapse circuit whose behavior in tests reproduced the function of a neuron, the building block of the human brain. In the future, this could be used in brain prostheses – or even combined into a massive network to create the first fully synthetic brain.

At the US Department of Energy (DOE)’s Lawrence Berkeley National Laboratory, researchers demonstrated the first true nano-scale waveguides for next generation optical communication systems. This holds potential for nano-scale photonic applications – such as intra-chip optical communication, signal modulation, nano-scale lasers and bio-medical sensing.

The DOE also funded a study with DARPA, in which scientists created a self-powering nano-device that harvested energy from vibrations (i.e. no batteries needed), while simultaneously transmitting data wirelessly over a range of 10 metres (33 ft). This technology could have major potential for devices ranging from airborne and stationary surveillance cameras, to wearable personal electronics, to implantable medical devices.

At Stanford University, researchers developed a new method of attaching nanowire electronics to the surface of any object, regardless of its shape or composition. The method could be used in making everything from wearable electronics and flexible displays to high-efficiency solar cells and ultra-sensitive biosensors.

Meanwhile, a new way of making battery electrodes was unveiled, based on nanostructured metal foams. In the future, this could lead to laptops that charge in a few minutes or cell phones that charge in 30 seconds.

At Tufts University in Massachusetts, researchers created the smallest electric motor ever devised – made from a single molecule. Electrons from a scanning tunnelling microscope were used to “drive” the directional motion of the molecule. A similar project – the world’s smallest electric car – was undertaken by Dutch scientists. Applications for molecular machines like these are probably some decades away, however.

British scientists made a nano-structure that multiplies stem cells used in therapies – a major step towards developing large-scale stem cell culture factories.

International researchers from the USA, Australia, Canada and South Korea used carbon nanotubes to create artificial muscles that could twist 1,000 times more than any similar material made in the past. This development could prove useful in future robotics and prosthetic limbs.

In Spain, researchers unveiled a process allowing complex shapes to be “carved” into nanoparticles, potentially revolutionising medical tests and drug treatments.

In Switzerland, researchers developed magnetic nanoparticles to remove harmful substances from the bloodstream. If successful, this method could be used to easily treat people suffering from drug intoxication, bloodstream infections, and certain cancers.

Meanwhile, German researchers demonstrated a graphene-based transistor array that is compatible with living biological cells and records the electrical signals they generate. This could lead to implantable “bio-electronics” which compensate for neural damage in the brain, eye, or ear.

As mentioned in Part 2, Intel unveiled its next generation of microprocessor technology, Ivy Bridge. These upcoming chips will be the first to use a 22 nanometre manufacturing process.

This carbon nanotube yarn can twist 1,000 times more than any suitable material made in the past. Credit: University of Texas at Dallas

Society & demographics

Arguably the biggest demographic “event” of 2011 happened on 31st October. The UN selected this as a symbolic date when the global population officially reached seven billion. The actual date and time of this milestone can’t be known for sure, however. The US Census Bureau, for example, has forecasted it for March 2012. Whatever the case, it is clear that humanity’s population continues to mushroom and is on course to reach over 9 billion by 2050.

How many people the world can sustain in the future will depend on the willingness of nations to cooperate in the face of growing resource shortages and accelerating environmental decline. Though technological advances could provide solutions to many problems, they will not always be politically or financially possible.

The fastest growing countries remain those in parts of Africa and the Middle East. On current trends, Nigeria’s population will soar from 167 million in 2011 to almost 730 million by 2100. The slowest growing regions are Russia and Eastern Europe, where some populations are actually declining.

China is facing pressure to alter its one-child policy. Experts warn that the country’s population is becoming dangerously unbalanced, with too few adults of working age supporting too many elders. Japan is experiencing a similar trend.

The Muslim population continues to grow rapidly. A study published by the Pew Research Center revealed that, on current trends, it is expected to increase by around 35% in the next 20 years – rising from 1.6 billion in 2011 to 2.2 billion by 2030.

Life expectancy continues to climb – driven by medical advances and rising living standards. The latest available figures from the World Health Organisation show that global average life expectancy is around 66 for men and 71 for women. Japan continues to lead, with 80 for men and 86 for women. Some countries have significant regional divides. In the UK, for example, men in London live up to 14 years longer than those in Glasgow.

2011 saw the number of married adults in the US hit a record low, according to a Pew survey. Just 51% of adults over 18 are married, compared with 72% in 1960. The median age at first marriage has never been higher for brides (26.5 years) and grooms (28.7).

Another study by Pew highlights a substantial generational divide in economic well-being. During the last quarter-century, US adults over 65 saw their net worth rise by 42%, while those under 35 saw theirs plummet by 68%.

A record-low 11% of Americans are satisfied with the job Congress is doing, according to a Gallup poll. In Europe, a median of 36% across 27 EU member states are confident in their government. Confidence appears to be lowest in southern and eastern Europe. Unsurprisingly, Greeks are the least hopeful among all EU members, with just 2% saying their local economy is getting better.

2011 – A look back (part 3)

Home & Leisure

2011 saw countless innovations in the home and leisure markets. Among them was Android@Home, announced by Google. This offers a new way of controlling home appliances, lights and other utilities, via smartphones and tablet devices.

There was also Nest, a new “learning” thermostat by Nest Labs. This remembers temperature adjustments entered over time, creating the most efficient schedule possible. It eliminates the hassle of changing the temperature settings manually, as well as conserving energy and saving money. It can also be controlled remotely using a smartphone.

LG launched a new 12kg washing machine, the largest ever capacity in a standard size machine. In addition to its huge size, this also features smart technology allowing you to remotely control functions through your smartphone.

In an effort to appeal to environmentally-conscious users, Samsung promoted its Eco Bubble series of washing machines. These use a whopping 70% less energy than standard machines. Beko’s new dishwasher, the DFN 71046 X30 beat the world record for energy efficiency, with 194kWh/year of consumption.

Beko also launched its quietest ever “Silent Tech” washing machine – which claimed to be five times quieter than comparable models – and Bosch released its Pro Silence Plus vacuum cleaner – with a noise output of just 71 decibels.

Philips unveiled its Perfect Care steam generator iron. This has one “perfect” setting for all fabric types, and its base will never burn. Philips also launched the Sonicare AirFloss, which offers a new way of flossing and removes up to 99% more plaque.

Self-cleaning fabrics were developed by Chinese scientists, while fragranced clothing triggered by exposure to light was described in a thesis written by scientist Dr. Olga Hinze of Cologne University.

3D printing continued to gain in prominence during 2011 – but has yet to become a widespread consumer product. It will likely be a few more years before it’s considered mainstream.

Lighting technology saw development, with a concept LED bulb featuring vastly improved efficiency, and an LED bulb with a filament bulb appearance. A report by the UK’s Energy Saving Trust showed that LED technology could be widespread by 2015 and will greatly improve the brightness, colour and distribution of lighting in housing communal areas.

Military & War

In April 2011, WikiLeaks, along with independent news agencies, began publishing hundreds of formerly secret documents relating to detainees at the Guantánamo Bay camp. These documents consisted of classified assessments, interviews and internal memos, written by The Pentagon’s Joint Task Force Guantanamo, headquartered at the Guantanamo Bay Naval Base. They revealed that over 150 innocent Afghans and Pakistanis – including farmers, chefs and drivers – were held for years without charge. It was also revealed that some of the prison’s youngest and oldest detainees suffered from fragile mental and physical conditions. They also contained statements from Khalid Sheikh Mohammed, confessing to interrogators that Al-Qaeda possessed nuclear capacity.

Meanwhile, the Pentagon released a report showing that China is now on track to forge a modern military by 2020, a rapid buildup that could be potentially destabilising to the Asia-Pacific region. This comes at a time when the US military itself is being downsized due to the spiralling national debt. The Chengdu J-20 – China’s first high-tech stealth fighter – had its first test flight in January 2011.

Among the other countries with military budget problems is Britain. The nation could lack a fully operational aircraft carrier until 2030, according to a report published by a spending watchdog.

Military technology saw many developments in 2011. A report released by the JASON defense science advisory panel highlighted the plunging cost of genome sequencing and its potential applications for the military. Among the suggestions was the mapping of military personnel’s genomes – to pinpoint the genetic traits best suited to handling battlefield stress, sleep deprivation, prolonged bleeding and other conditions. This could help in selecting better personnel for specific missions.

At the Massachusetts Institute of Technology, researchers developed a radar system allowing soldiers to see through walls from over 60ft away.

At the University of Pittsburgh, scientists used pig cells to regrow soldiers’ destroyed muscles, including the nerves and tendons necessary to restore function. This form of regenerative medicine is seeing rapid development and may soon be “a standard of care for orthopedists and trauma surgeons.” Entire limbs could one day be fully replaceable. Soldiers with horrific injuries from IED blasts, for example, could have their lives returned to normal.

In August, the US Office of Naval Research successfully tested a revolutionary new type of explosive material. Damage is caused to the target not only by a high speed collision with dense material, but by further energy as chemicals react in the material. Known as “High-Density Reactive Material” (HDRM), it will replace steel in warhead casings and could dramatically increase weapons’ impacts. As a result, less ordnance and fewer sorties will be needed to get the same result. Because the material only reacts when involved in a high energy collision, there will be less collateral damage to innocent bystanders, too.

A German defence manufacturer demonstrated a new laser gun that could be fitted to vehicles – blasting everything from incoming mortar shells to roadside bombs.

In November, the Department of Defense announced the successful test of a hypersonic missile. Travelling at five times the speed of sound, this new weapon system is capable of striking targets 2,300 miles (3,700 km) away in less than 30 minutes. It is being developed as part of the Prompt Global Strike program.

Meanwhile, the US Air Force took delivery of the first GBU-57A/B (Massive Ordnance Penetrator) – a 30,000-pound (13,608 kg), precision-guided “super bunker buster”. This monstrous weapon can penetrate 200ft of reinforced concrete before it goes off, and is substantially larger than the deepest penetrating bomb previously available, the 5,000-pound (2,268 kg) GBU-28. It will be the largest non-nuclear bomb in the US arsenal.

As mentioned in part 1, 2011 also witnessed the Arab Spring, the Libyan civil war and overthrow of Gaddafi, the death of bin Laden and the end of the Iraq War. Additionally, the Basque separatist militant organisation ETA declared a “definitive cessation of its armed activity”, after 43 years of political violence which had killed over 800 people since 1968.

The GBU-57A/B (massive ordnance penetrator)

2011 – A look back (part 2)

Computers & the Internet

2011 saw chipmaker Intel unveil its latest generation of microprocessor technology, codenamed Ivy Bridge. These chips – due for retail launch in April 2012 – will be the first to use a 22nm manufacturing process, packing transistors even more densely than the previous 32nm system. For comparison, the width of an average human hair is about 90,000nm.

Later in the year, the company showed off a new accelerator chip running at speeds of 1 teraflop (a trillion calculations per second). This device, dubbed Knights Corner, combined 50 individual processor cores onto a single chip.

British chipmaker ARM – whose designs are used in 95% of the world’s smartphones – revealed a new processor and graphics card, paving the way for cheaper, faster mobiles. The company believes that smartphones could be produced for under £60 ($100) by 2013 or 2014.

In the world of supercomputers, Japan achieved first place on the Top 500 list, ending China’s reign at the top after just six months. Capable of operating at 8.16 petaflops, the K computer was more powerful than the next five systems combined. It later received an upgrade and became the first computer to exceed 10 petaflops.

In Germany, a new physical phenomenon was found that could yield transistors with greatly enhanced capacitance — a measure of the voltage required to move a charge. This may lead to a revival of clock speed as the measure of a computer’s power.

Meanwhile, the first graphene integrated circuit was developed by scientists at IBM. If commercialised, this should continue the exponential trend of Moore’s Law for decades to come.

At the Massachusetts Institute of Technology, researchers designed a computer chip that mimics the way a human brain’s neurons adapt in response to new information.

At the University of Illinois, engineers developed self-healing electronics that restore conductivity to damaged circuits.

The first millimetre-scale computing system was developed in 2011 – in the form of a prototype, implantable eye pressure monitor for glaucoma patients. This ultra-compact device packs a microprocessor, pressure sensor, memory, solar cell, thin-film battery and wireless radio into just over a cubic millimetre. It is expected to be commercially available several years from now.

2011 saw breakthroughs in quantum computing. These included the successful controlled entanglement of 14 quantum bits (qubits) – the largest quantum register yet produced. A single chip holding a total of nine quantum devices was also developed.

D-Wave systems claimed to have developed a 128-qubit machine, which they labelled “the world’s first commercially available quantum computer”. However, this claim was disputed by others and received heavy criticism from a number of scientists.

The number of Internet users worldwide reached 2 billion in 2011, with mobile phone users reaching 5 billion. Most of this growth came from emerging economies such as China. The UN declared that Internet access should be a human right.

Facebook, Twitter and other social media continued to grow in popularity and reach. They played a significant role in the organisation and broadcast of protests, riots and other unrest – especially in the Middle East.

The tablet market surged in 2011, with almost 73 million units shipped globally, a staggering 256 percent increase over 2010. Tablets now account for 25.2 percent of the mobile PC market, with market share dominated by the iPad.

The tech world also mourned the loss of Apple pioneer Steve Jobs.

The first complete millimetre-scale computing system. Credit: Gyouho Kim

Energy & the Environment

Climate change received surprisingly little coverage in the mainstream media last year. This was despite the United States facing the most billion-dollar climate disasters ever, with at least 12 distinct disasters costing $52 billion to the economy. Texas, Arizona and New Mexico all experienced the biggest wildfires in recorded history, with Texas being ravaged by an “off the charts” drought and extreme heat.

2011 was an exceptionally destructive and deadly year for tornadoes with 522 fatalities in the US alone – the second highest figure on record. The worst affected city was Joplin, Missouri, which was devastated by winds peaking at 250 mph (402 km/h).

Meanwhile, torrential flooding along the Mississippi River resulted in many counties being declared federal disaster zones. Army Corps were forced to blow up a levee, sacrificing 130,000 acres of farmland to save a small town.

Hurricane Irene left extensive flood and wind damage along its path through the Caribbean, the US East Coast and as far north as Atlantic Canada.

In Africa, extreme drought caused a severe food crisis across Somalia, Ethiopia and Kenya – affecting 13 million people. The UN described it as “the worst humanitarian disaster in the world”.

Europe’s second largest river, the Danube, was reduced to a trickle in places, with shrinking water levels exposing bombs and debris from the Second World War. The UK had its second warmest year on record, parts of Norway in November were 5.3°C (9.5°F) above normal, and much of northern Europe had the driest end to a year since records began in 1881.

In Australia, there were record floods, with freak weather causing six inches of rain to fall in just 30 minutes in places.

Thailand suffered major floods – with 12.8 million people affected and nearly 800 fatalities. Thailand is the 2nd largest producer of computer disk drives, accounting for 25% of global production; the resulting disruption to industry led to a worldwide supply shortage and rocketing prices.

In the Philippines, Tropical Storm Washi caused 1,257 fatalities and left over 300,000 homeless.

In the Arctic, sea ice reached its second-lowest extent on record – both for the daily minimum extent and the monthly average. Arctic ice may be thinning up to four times faster than the IPCC’s earlier predictions, according to a new study by MIT’s Department of Earth, Atmosphere, and Planetary Sciences.

Global CO2 emissions jumped by a record amount, more than in the worst-case scenario outlined by climate experts. Atmospheric concentrations of CO2 now stand at 392 parts per million, or about 40% higher than pre-industrial levels.

2011 also brought worrying news from Siberia, where scientists reported seeing vast plumes of methane bubbling upward.

The Earth’s surface is undeniably warming – according to a detailed new analysis called the Berkeley Earth Project (which was, ironically, funded by the Koch brothers).

Furthermore, new research suggests that at least three-quarters of the rise in average global temperatures since the 1950s is due to human industrial activity.

According to an American Physical Society report, technologies for removing carbon dioxide from the atmosphere are unlikely to offer an economically feasible way to slow human-driven climate change for several decades.

2011 was also notable for continuing high food prices, though they declined slightly towards the end of the year.

Aside from climate change, 2011 was also an exceptional year for earthquakes. By far the most damaging was the 9.0 magnitude quake in Japan, triggering a tsunami which caused the worst nuclear disaster since Chernobyl. 15,844 were confirmed dead, with 125,000 buildings damaged or destroyed, around 4.4 million households left without electricity and 1.5 million without water. The World Bank put the economic cost at $235 billion, making it the most expensive natural disaster in world history.

All in all, 2011 was an extremely bad year for the environment. There were reasons to be positive, however, as global deployment of solar PV continued to grow exponentially. In fact, solar is now the fastest growing industry in America. One prominent futurist, Ray Kurzweil, has even gone so far as to claim that solar will continue on this exponential path and could solve all our energy and environmental needs by 2028. Whether this bold and almost utopian prediction has any merit remains to be seen.

2011 – A look back (part 1)

To kick off 2012, here’s a look back at some of the events, trends, scientific and technological advances that shaped 2011.

These have been divided into categories for ease of reference.

AI & Robots

2011 witnessed a major milestone in artificial intelligence, as the Watson supercomputer defeated two human champions on the Jeopardy! quiz show. This computer proved capable of answering questions posed in natural language on a wide range of subjects. Though some are skeptical over whether it displayed “intelligence”, its performance was undoubtedly impressive.

Advances in robotics technology this year were also significant. They included PETMAN, a humanoid machine from Boston Dynamics with eerily realistic movements. There were also quadro-copters, able to hit a ball to-and-fro while hovering in the air (and even construct a tower), a revamped Asimo with enhanced capabilities, a new version of the NAO robot, and a major step towards microscopic, remote-controlled robots that could one day travel inside the human body. One of the more bizarre developments came from Japan, in the form of a flexible bionic mouth able to replicate human singing.

The number of robots worldwide continued to grow rapidly and is now on course to reach 100 million by 2020.

Biology & Medicine

2011 saw a multitude of breakthroughs and discoveries in medicine. Among the most notable was an HIV vaccine trial that received the go-ahead from the FDA, following two decades of research by Canadian scientists. Gene therapy was also shown to protect mice from HIV transmission.

Meanwhile, a new leukaemia treatment was described by some as “the biggest advance in cancer research in decades”.

At a medical conference in Chicago, two new drugs for skin cancer were unveiled and received similar praise as “the biggest breakthrough in melanoma treatment for more than 30 years”.

A trial involving heart failure patients – treated with stem cells to repair their severely damaged hearts – resulted in triple the improvement researchers had predicted. It was the first time this had been done in humans and was described as “the biggest breakthrough in treating heart attacks for a generation”.

In Sweden, the first synthetic organ transplant – using an artificial windpipe coated with stem cells – saved the life of a man diagnosed with terminal cancer.

The world’s first tissue-engineered urethras were also developed using patients’ own cells.

Other advances included a universal flu vaccine that could potentially kill all strains, a pill preventing Type 2 diabetes in 72% of patients, trials of a pancreatic cancer vaccine, a breakthrough in the treatment of sickle cell anaemia, the beginning of human trials for a malaria vaccine, another step towards an obesity drug, a new dye to illuminate hard-to-spot tumours, and prostate cancer being cured in mice.

Researchers found three more genes linked to the most common form of breast cancer, as well as five genes linked to Alzheimer’s.

Progress was made in identifying the root molecular cause of aging (triggered by a gene called p53) and a telomerase activator known as T-65 was shown to increase telomere length and prolong the lifespan of adult/old mice, without cancerous side effects. Researchers also identified a new group of mitochondrial proteins, the absence of which allows other protein groups to stabilise the genome and could delay the onset of age-related diseases.

A new way of delivering drugs to the brain was discovered, using the body’s own exosomes.

Meanwhile, genome editing was achieved for the first time in mice, to cure a life-threatening blood disease. This method, which repairs flaws in the genetic code of a living animal, could one day be applied to humans.

India almost completely eradicated polio in 2011, through an extensive vaccination program. Only a single case of polio was reported during the whole of the year – compared with 42 in 2010, and 741 in 2009.

Also in 2011, the United Nations declared that a once-widespread cattle disease, rinderpest, had been globally eradicated.

The world's first synthetic organ transplant

Business & Politics

2011 was of course dominated by the eurozone crisis, which saw Greece in the spotlight for much of the year. Embroiled in economic, political and social turmoil, the Greek Prime Minister, George Papandreou, and the main opposition leader agreed to form a “national unity” coalition government. This was needed to pass highly unpopular austerity plans, secure bailout funds and prevent the country from defaulting on its debt. As part of this deal, Papandreou agreed to resign.

Italy faced major problems too. Its cost of borrowing on 10-year bonds reached more than 7%, the highest since the euro was founded in 1999. This prompted the European Central Bank to intervene and was followed by Silvio Berlusconi’s resignation.

Europe as a whole remains highly vulnerable going into 2012, with no end in sight to the ongoing crisis. According to a BBC poll of leading economists, the continent will fall back into recession. Funding needs are estimated at over €800 billion for this year, with €215 billion euros for Italy alone. French banks have €310 billion of exposure to Italy, while German banks have €155 billion of exposure to France. The FTSE 100 finished 2011 almost 10% lower than at the start of the year.

America’s debt continued to rise, passing 100% of GDP and reaching $15 trillion by December. The last time it rose this high was during World War II. Its triple-A credit rating was also downgraded for the first time. There was some good news, however, as unemployment fell, from 9.4 down to 8.6% (the lowest since March 2009).

China continued to have strong economic growth in 2011 and surpassed the United States as the leading manufacturer. However, more signs emerged of a looming real estate bubble, and the IMF also warned that government-controlled banks could be storing up imbalances potentially hampering future growth.

2011 also witnessed the Arab Spring (interactive timeline here), the Libyan civil war and overthrow of Gaddafi, the death of Osama bin Laden, the birth of a new country, widespread looting and fires in England, the Occupy movement and the end of the Iraq War.

The year ended with tension between Iran and the US over the Strait of Hormuz – a strategically vital waterway, through which almost 20 percent of the world’s oil passes.

Two highly controversial bills – SOPA and NDAA – were debated in the US (the latter being signed into law on 31st December).

Occupy Wall Street protesters. Credit: Thomas Good / NLN

Self-healing electronics could work longer and reduce waste

When one tiny circuit within an integrated chip cracks or fails, the whole chip – or even the whole device – is a loss. But what if it could fix itself, and fix itself so fast that the user never even knew there was a problem?

Engineers at the University of Illinois have developed a self-healing system that restores electrical conductivity to a cracked circuit in less time than it takes to blink. Led by aerospace engineering professor Scott White and materials science and engineering professor Nancy Sottos, the researchers published their results in the journal Advanced Materials.

“It simplifies the system,” said chemistry professor Jeffrey Moore, a co-author of the paper. “Rather than having to build in redundancies or to build in a sensory diagnostics system, this material is designed to take care of the problem itself.”

As electronic devices are evolving to perform more sophisticated tasks, manufacturers are packing as much density onto a chip as possible. However, such density compounds reliability problems, such as failure stemming from fluctuating temperature cycles as the device operates or fatigue. A failure at any point in the circuit can shut down the whole device.

“In general there’s not much avenue for manual repair,” Sottos said. “Sometimes you just can’t get to the inside. In a multilayer integrated circuit, there’s no opening it up. Normally you just replace the whole chip. It’s true for a battery too. You can’t pull a battery apart and try to find the source of the failure.”

Most consumer devices are meant to be replaced fairly regularly, adding to electronic waste issues, but in many important applications – such as instruments or vehicles for space or military functions – electrical failures can’t be replaced or repaired.

The Illinois team previously developed a system for self-healing polymer materials and decided to adapt their technique for conductive systems. They dispersed tiny microcapsules, as small as 10 microns in diameter, on top of a gold line functioning as a circuit. As a crack propagates, the microcapsules break open and release the liquid metal contained inside. The liquid metal fills in the gap in the circuit, restoring electrical flow.

Click to enlarge.

“What’s really cool about this paper is it’s the first example of taking the microcapsule-based healing approach and applying it to a new function,” White said. “Everything prior to this has been on structural repair. This is on conductivity restoration. It shows the concept translates to other things as well.”

A failure interrupts current for mere microseconds as the liquid metal immediately fills the crack. The researchers demonstrated that 90 percent of their samples healed to 99 percent of original conductivity, even with a small amount of microcapsules.

The self-healing system also has the advantages of being localised and autonomous. Only the microcapsules that a crack intercepts are opened, so repair only takes place at the point of damage. Furthermore, it requires no human intervention or diagnostics, a boon for applications where accessing a break for repair is impossible, such as a battery, or finding the source of a failure is difficult, such as an air- or spacecraft.

“In an aircraft, especially a defense-based aircraft, there are miles and miles of conductive wire,” Sottos said. “You don’t often know where the break occurs. The autonomous part is nice – it knows where it broke, even if we don’t.”

Next, the researchers plan to further refine their system and explore other possibilities for using microcapsules to control conductivity. They are particularly interested in applying the microcapsule-based self-healing system to batteries, improving their safety and longevity.

Paint-on solar cells developed

Imagine if the next coat of paint you put on the outside of your home generated electricity from light — electricity that could be used to power the appliances and equipment on the inside.

Researchers at the University of Notre Dame have taken a major step towards this vision by creating inexpensive “solar paint” that uses semiconducting nano-particles to produce energy.

“We want to do something transformative, to move beyond current silicon-based solar technology,” says Professor Prashant V. Kamat, an investigator in Notre Dame’s Center for Nano Science and Technology (NDnano), who leads the research.

“By incorporating power-producing nanoparticles, called quantum dots, into a spreadable compound, we’ve made a one-coat solar paint that can be applied to any conductive surface without special equipment.”

Photo Credit: ACS Nano

The team’s search for the new material, described in the journal ACS Nano, centered on nano-sized particles of titanium dioxide, which were coated with either cadmium sulfide or cadmium selenide. The particles were then suspended in a water-alcohol mixture to create a paste.

When the paste was brushed onto a transparent conducting material and exposed to light, it created electricity.

“The best light-to-energy conversion efficiency we’ve reached so far is 1 percent, which is well behind the usual 10 to 15 percent efficiency of commercial silicon solar cells,” explains Kamat.

“But this paint can be made cheaply and in large quantities. If we can improve the efficiency somewhat, we may be able to make a real difference in meeting energy needs in the future.”

“That’s why we’ve christened the new paint, Sun-Believable,” he adds.

Kamat and his team also plan to study ways to improve the stability of the new material.

Self-cleaning clothes

Chinese scientists have developed a special nano-particle coating. When applied to cotton, it causes the fabric to clean itself and remove odours if exposed to sunlight.

The alcohol-based compound is made with titanium dioxide. This is known to be an “excellent catalyst in the degradation of organic pollutants.” It breaks down dirt and kills microbes when exposed to some types of light.

Self-cleaning fabrics have been made in the past, but they only worked if exposed to ultraviolet rays. This new fabric cleans itself in the presence of ordinary sunlight.

The researchers say the method is cheap, non-toxic and ecologically friendly. Retail experts say the innovation could prove popular with retailers due to rising demand for “functional clothing”. The nano-particles remain embedded after washing and drying.

More information can be found in Applied Materials and Interfaces.

LEDs offer brighter future

Light-emitting diodes (LEDs) have for many years been used as indicators such as red standby dots on TVs. At first, they were available only as a red light source, and their output was too low for general illumination. As the technology developed, other colours became available and the lamps became brighter, so LEDs found other roles in a wide range of appliances and equipment.

Now, a new study by the UK’s Energy Saving Trust has shown that LED technology can dramatically improve the brightness, colour and distribution of lighting in social housing communal areas.

Not only that, but it can deliver huge energy savings (up to 90%), and reduce long-term costs and maintenance, while making residents feel safer.

Credit: The Energy Saving Trust

The study measured the performance of 4,250 LED light fittings installed at 35 sites. The authors of the report calculated that the LED fittings saved over 3.4 million kilowatt hours (kWh) each year when compared with the previous systems – equivalent to lighting 5,800 average UK homes for a year with traditional lighting.

Residents commented that their buildings felt safer, more secure and more pleasant because they were better illuminated. The light was fresher, brighter and more like daylight.

With spiralling energy prices, the high efficiency of LED lamps will make them a very attractive investment in the future. It is predicted that the technology will dominate the commercial and domestic lighting markets by 2015.

You can download the full report at the Energy Saving Trust website here: http://www.energysavingtrust.org.uk (PDF).

Credit: The Energy Saving Trust

Global warming news

Worrying news from the Arctic, where a team of Russian scientists have been conducting a survey of the East Siberian Arctic Shelf. They report seeing plumes of methane – “continuous, powerful and impressive seeping structures, more than 1,000 metres in diameter” – bubbling to the surface.

There are hundreds of millions of tons of methane gas locked away beneath the Arctic permafrost and seabed. This particular greenhouse gas is over 20 times more effective at trapping heat than carbon dioxide.

As global average temperatures continue to rise, more and more ice is disappearing from the Arctic, which is the fastest warming area of the planet. If the Siberian permafrost continues to melt, vast amounts of trapped methane could be suddenly belched into the atmosphere – leading to abrupt, severe and possibly irreversible climate change.

Read more in The Independent.

Capturing the speed of light on camera: 1 trillion frames per second

By using optical equipment in a new and totally unexpected way, MIT researchers have created an imaging system that makes light appear slow. The system acquires visual data at the rate of one trillion exposures per second, or about 40 billion times faster than a typical video camera. That’s fast enough to produce a slow-motion film of a light beam passing through a one-litre bottle, bouncing off the cap and reflecting back to the bottle’s bottom.

Direct recording of light is impossible at that speed, so the camera takes millions of repeated scans to recreate each image. Because the imaging system requires multiple passes to produce its videos, this means it can only record events that are precisely repeatable.

Despite this drawback, the team hopes the technique could be used to understand a range of ultra-fast processes, to analyse faults and material properties, or in medical imaging, e.g. ultrasound with light. In addition, the photon path analysis will allow new forms of computational photography, such as rendering and re-lighting photos using computer graphics techniques.

One of the system’s developers, Andreas Velten, calls it the “ultimate” in slow motion: “There’s nothing in the universe that looks fast to this camera,” he says.

For more info about this process – known as “femto photography” – see the MIT website.