|
|
||||
|
|||||
|
|
|||||
Top Stories in Science
|
July 2007 Issue |
| [D] Defence and security |  |
|
|
|
|
|
Desertification threat to global stability About a third of the world's population is vulnerable to desertification and some 50 million people could be displaced within the next 10 years, a new UN report warns. The main problem areas are in sub-Saharan Africa, where people are moving to northern Africa or to Europe, and in the former Soviet republics of Central Asia. The displacement of tens of millions of people will put new strains on natural resources and on other societies nearby and could soon threaten international instability. The report recommends using technology, aid and international trade to provide threatened populations with alternative livelihoods that put less pressure on natural resources; for example, using the abundant solar energy in desert regions to create other economic activities. [D][E][X]
Environmental security Speaking in Washington on the urgent need for action on climate change, the UK Chief Scientific Advisor has said that wealthy and developing nations must reach an emissions-reduction agreement by 2009, to allow it to come into force by 2012. He added that there is a huge and growing global market for environmental goods and services, predicted to grow to $800 billion by 2015. He noted that, as part of the EU's Emissions Trading Scheme, London has become a leader in carbon trading, with a market worth more than 9 billion pounds. [D][E][P][X]
Extensively drug-resistant TB According to the WHO, extensively drug-resistant TB (XDR-TB) is now a threat to the security and stability of global health, with the potential to develop into an untreatable epidemic. So far, XDR-TB has been confirmed in 37 countries, and there are around 2500 new cases per month. An international task force has recommended how to contain both XDR-TB and the less grave but more widespread problem of multi-drug resistance TB (MDR-TB). Based on its findings, the WHO has now announced a 2-year plan to greatly improve detection of MDR-TB and XDR-TB cases and also improve the rapid provision and correct use of treatment drugs. [D][H]
Combating a flu pandemic Treatment with the oral antiviral Tamiflu (oseltamivir) and prophylaxis for people exposed to infected patients could be one of the most cost-effective strategies for reducing illness and death during an influenza pandemic, according to model-based research at the University of Toronto. The researchers estimate that Tamiflu sufficient to cover 65 percent of a country’s population could cut the number of deaths in a pandemic by half. [D][H] |
||
| [A] Aeronautics and space | |
|
|
|
|
|
787 Dreamliner Boeing has unveiled its 787 Dreamliner, which it says is far more fuel efficient than previous airliners and produces 20 percent less carbon dioxide emissions. Carbon fibre makes up about half of the plane's structure, including the fuselage and wings, and titanium makes up 15 percent. As well as giving fuel efficiency, using carbon fibre composite instead of aluminium allows the cabin air to be kept more humid and at higher pressure, which means that long-haul passengers should be less jetlagged. Most aircraft are designed to have a minimum cabin pressures equivalent to 8,000 feet altitude. The 787 cabin pressure will be equivalent to 6000 feet altitude, and new research shows this reduces various forms of discomfort on long haul flights. [A][E][M][P]
Low carbon planes Airbus has announced that it is committed to reducing carbon dioxide emissions from its planes by half between now and 2020. [A][E][M][P]
Travel and deep-vein thrombosis Phase I of the WHO Research Into Global Hazards of Travel (WRIGHT) project has reported that the risk of developing deep vein thrombosis on an air flight roughly doubles after travel lasting four hours or more, to about 1 in 6000. It is due to immobility and not specifically to air travel. One study found that those taking multiple air flights over a short period of time are also at higher risk. This is because the risk does not go away completely after a flight is over, but remains elevated for about four weeks. [A][H]
Space tourism EADS Astrium, which builds the Ariane rocket, plans to develop a space plane capable of carrying fare-paying passengers on a sub-orbital ride to an altitude of more than 100km. The vehicle will take off from a normal airport and give the tourists a three-to-five-minute experience of weightlessness at the top of its climb. The plane will use normal jet engines to take off and climb to 12km. From there, a rocket engine will take over. As the plane falls back to Earth, the pilot will use small thrusters to control its altitude, guiding the vehicle into the atmosphere from where it will use its jet engines to return to the airport. The total journey time will be about one-and-a-half hours. The company says that flights are likely to begin in 2012. [A][P]
Automatic transfer vehicle The European robotic craft for resupplying the International Space Station is being shipped to the Kourou launch site. It will be launched on a specially prepared Ariane 5 in early 2008 and is designed to dock with the ISS, delivering 7.5 tonnes of food, water, pressurised air, fuel and experiments. Its engines can also re-boost the station's orbit to overcome the effects of atmospheric drag. After six months, the vehicle will undock, bearing station waste, and then burn up in a controlled re-entry. Successive ATVs will resupply the ISS annually. Cutting the cost of transporting material and experiments to and from the ISS is very important to its future. At present, the high cost is deterring government agencies and private companies from using the ISS even though NASA is offering room on the station essentially for free. [A]
3D magnetic reconnection ESA's Cluster satellites have obtained the first ever 3-D picture of magnetic reconnection in the Earth's magnetosphere and have shown that it has the 3-D double structure that was theoretically predicted. In magnetic reconnection, magnetic field lines from different magnetic domains collide and reconnect, mixing previously separated plasma. It occurs in star formation, solar explosions and the entry of solar wind energy into the near-Earth environment. [A][P][R]
Evidence that Mars had oceans Canadian and US researchers have uncovered evidence that ragged, kilometre-high undulating features on the surface of Mars are shorelines of massive ancient oceans that once covered one-third of the planet in water. In the 1990s, NASA's Mars Global Surveyor spacecraft mapped the Martian topography and found that these features, which are 2 to 4 billion years old, vary in elevation by about half of mile to more than a mile and a half. Since old shorelines on Earth remain nearly flat relative to sea level, there was widespread scepticism that these features could really be ancient shorelines. However, the researchers have shown their topography can in fact be explained by a shift in the planet’s spin axis within the past 2 to 3 billion years that deformed the shorelines. [A]
Alien life The search for life elsewhere in the solar system and beyond should include efforts to detect life with an alternative biochemistry to that of life on Earth, according to a report from the US National Research Council. Water might not be necessary for life as liquids such as ammonia or formamide could also work as biosolvents that dissolve substances within an organism, albeit through a different biochemistry. DNA on Earth works through the pairing of four nucleotides, but experiments in synthetic biology have created structures with six or more nucleotides that can also encode genetic information and, potentially, support Darwinian evolution. Additionally, studies show that an organism could utilize energy from alternative sources, such as through a reaction of sodium hydroxide and hydrochloric acid, meaning that such an organism could have an entirely non-carbon-based metabolism. [A][E][G][R]
Life in the galaxy New technology has enabled astronomers to detect exceedingly faint radio emissions produced by molecules around a star called VY Canis Majoris. This star, about 5000 light year from Earth, is a dying red hypergiant estimated to be 25 times the Sun's mass and nearly half a million times the Sun's brightness, making it one of the most luminous stars in the galaxy. The radio emissions show that it is emitting a surprisingly large quantity of molecules, many important to life. This implies that the chemistry that leads to life may be more widespread in the universe and more robust than previous studies have suggested. [A][F][R]
Pioneer anomaly Launched in the early 1970s, NASA's Pioneer 10 and 11 spacecraft are now drifting out of the solar system in opposite directions, gradually slowing down as the Sun's gravity pulls back on them. They are slowing down slightly more than expected and this has led to the suggestion that the theory of gravity may need revising. However, a Norwegian physicist has now calculated that it is impossible to modify gravity in ways that would match the Pioneer anomaly without getting the wrong predictions for the orbital motion of Uranus and Pluto. This leaves the possibility that the anomaly might be caused by drag due to dust grains in space, or by anisotropy in the emission of heat from small nuclear generators on board the spacecraft. To test this, NASA is compiling additional data from Pioneer 10 and 11 that had been locked in archaic file formats and storage media. If this does not explain the anomaly, there remains the possibility that the spacecraft are experiencing gravity differently because they are moving away from the Sun rather than in orbit round it. This would mean that Einstein's equivalence principle needs revising. [A][F] |
||
| [U] Unmanned vehicles and robotics | |
|
|
|
|
|
Semi-automated vehicles IBM Researchers are conducting pioneering research into active safety and driver assist technologies in vehicles that exchange information with each other and with the road infrastructure, take corrective action where appropriate, and provide essential feedback to the drivers to help avoid dangerous situations. Such electronic "reflexes" are faster than human actions and will allow vehicles to be closer to one another on the road, improving the flow without compromising safety. Humans, however, will remain better than machines at analyzing complex situations. [U][E][I][K][R][V]
Motion control Flies are very adept fliers and have excellent flight control. Surprisingly, however, the flight control centre in the fly’s brain contains only 60 nerve cells. Understanding how the fly's brain achieves such complex tasks with so little resources may be useful for controlling movement in robots. Researchers have studied a subset of ten neurons that enable a fly to detect rotational axes. They found that an unusual but simple direct electrical connection exists between neighbouring nerve cells. This cleverly enables the network to detect rotational axes for difficult scenes that yield little or no information when rotated because they contain large areas with similar contrast, such as the sky. [U][A][B][R]
Brain's inertial navigation system Researchers have found that so-called Purkinje cells in the cerebellum performs inertial navigation calculations, elegantly combining rotational signals from the semicircular canal in the inner ear with gravity signals in order to figure out the overall 3-D movement. [U][B]
Air muscle hand A Japanese company has unveiled what it calls the world's first prototype of an artificial hand with "air muscles" that can do delicate work like picking up a raw egg. The hand, which has five human-sized fingers, weighs only 400gm. Compared with motor-driven hands, air muscle hands are not only much lighter but also less noisy. [U][V][W] |
||
| [P] Propulsion and energy | |
|
|
|
|
|
Superconducting turbofan engine According to scientists at Florida State, NASA and Georgia Tech, it should be possible to build a superconducting turbofan for an all-electric aircraft that could be quieter and more efficient than conventional aircraft, and would counter the increasing impact of air travel on global warming. They propose using liquid hydrogen to cool magnets made of high temperature superconductor such as YBCO, and also to power fuel cells to supply the electricity. A superconducting motor is not only lightweight but also efficient electrically, generating three times the torque of a conventional electric motor for the same energy input and weight. The researchers estimate that a YBCO turbine would generate as much power as a single-engine Cessna aircraft for roughly half the weight. [P][A][E][M]
Mach 10 scramjet A supersonic scramjet engine has successfully achieved 10 times the speed of sound during a test at the Woomera range, according to the Australian Defence Science and Technology Organisation (DSTO). [P][A]
VASIMR engine A revolutionary plasma rocket engine that could reduce travel times for space missions has been tested for a record time of more than four hours. The engine works by stripping electrons from hydrogen atoms and accelerating the resulting plasma in an electric field. Expelling the plasma out of the back of the engine generates thrust. The technique is known as Variable Specific-Impulse Magnetoplasma Rocket (VASIMR) technology, and was conceived in the 1970s. Hydrogen for fuel is common throughout the universe, and might be harvested by a spacecraft en route. [P][A]
Future of nuclear power A review article in the July issue of PhysicsWeb discusses the prospects for a revival in nuclear power, including the advantages of third and fourth generation nuclear reactors, and issues of reactor safety and waste disposal. [P][E][T][U][W][X]
Deep coal seam sequestration Worldwide, deep unmineable coal seams could potentially provide trillions of tonnes of storage capacity for permanently sequestering carbon dioxide. At the same time, the sequestered gas could displace methane from the coal beds, enabling it to be extracted for fuel. An initial US feasibility assessment based on 2000 coal samples taken from 250 coal beds across the US has found that some sources of coal hold vast quantities of methane. However, the deeper seams were found to contain less methane and to be more compacted, making them much less porous. The researchers say that this lower porosity is a potential problem that will have to be overcome if deep coal seam sequestration is to be widely used. [P][E]
Wave power Wave-power generators that work on the surface are very vulnerable to violent storms and can also interfere with shipping. An alternative idea is to harness wave energy using underwater buoys anchored to the sea bed and positioned 50 metres below the surface. The energy generation is driven by the changes in pressure that waves produce by increasing and decreasing the water column above the buoys. A small field of 5 buoys will be tested off Scotland in 2008. Waves of sufficient size to pump the buoys exist in the North Atlantic from Scotland to Portugal, along the Pacific US shoreline, along the coast of Chile, and in South Africa and New Zealand, according to the buoy's developers. [P][E]
Wave power and sea defences Partners in an EU-funded project have developed a new wave energy converter that they say can outperform other wave energy systems. They are building a full-scale prototype off the coast of Norway. Called the Seawave Slot-Cone generator (SSG), it works on the wave overtopping principle, using a total of three reservoirs built on top of each other. The water captured in the reservoirs then runs through a multi-stage turbine for electricity production. Having three reservoirs enables the generator to harness waves of various sizes and to operate continuously. The converter can be integrated into breakwater infrastructures, thus providing both energy and sea defences. The generator should prove sufficiently rugged and reliable as it has very few moving parts. [P][E]
New biofuel process A new environmentally benign process can turn plants into energy-dense fuel by combining fermentation and chemical reactions. It produces hydroxymethylfurfural (HMF), which can be used to create plastic polymers and other chemicals, and dimethylfuran (DMF), which could replace ethanol as a fuel. Compared with using fermentation to produce ethanol, the new process utilizes more of the carbohydrates in the plants and is much faster. Provided that DMF does not have any toxicological problems, it could prove a good alternative to ethanol. It provides more energy than ethanol and has a higher boiling point allowing it to be blended more easily with gasoline. Also, unlike ethanol, it does not absorb atmospheric water vapour. [P][E][M]
Extremophiles and biofuel More than a billion tons of biomass is estimated to be created each year in the timber and agricultural industries, as well as a variety of grasses and other potential energy crops. The challenge is to find cost effective industrial processes to turn a wide range of lignocellulosic material into biofuel and plastics. Research teams around the world are studying various biological organisms that are able to digest biomass in the hope of finding suitable enzymes or organisms. One possibility is to use extremophile microorganisms, such as can be found in sulphurous deep-sea vents, hot springs and gold mines. Extremophiles and their enzymes are well adapted to thrive in the conditions of high temperature and low pH likely to be needed for lignocellulosic processing. [P][E][G][M]
Growth of renewable energy sector Renewable energy and energy efficiency industries are seeing soaring investment, according to a trend analysis from the UN Environment Programme. While renewables are currently only 2 percent of the installed power mix, they now account for about 18 percent of world investment in power generation, with wind generation at the investment forefront. Solar and bio-fuel energy technologies grew even more quickly than wind, but from a smaller base. The report attributes the sector’s boom to a range of global concerns – climate change, increasing energy demand and energy security foremost among them. [P][D][E][M][T][W]
Carbon-neutral home The UK's first carbon-neutral home has been unveiled at the Offsite 2007 exhibition. It is the first design to achieve level six of the Code for Sustainable Homes - the carbon neutral standard that will be applied in 2016 to new UK homes. The two-bedroom house is insulated to lose 60 percent less heat than a normal home. It also features solar panels, a biomass boiler and water efficiency devices such as rainwater harvesting. The design meets zero-emission rules to be applied to new UK homes from 2016 onwards. [P][E][M][S] |
||
| [M] Materials, structures and surfaces | |
|
|
|
|
|
Multiferroic materials Multiferroic materials that are simultaneously ferromagnetic and ferroelectric could open up a new approach in electronics. A tiny magnetic field might control an electric current or a tiny electric signal might reverse the magnetic field of the material, or magnetically align electron spins in spintronic devices. Unfortunately, the usual mechanisms that produce ferroelectricity and ferromagnetism are incompatible at an atomic level, so they rarely occur together. However, recent research has shown that rare earth manganites become multiferroic at low temperatures. The materials form so-called spin-density waves, where the bar-magnet-like spins of the atoms organize into sheets alternately pointing in opposite directions. Now Dutch researchers have proposed a theory that explains this and also suggests looking for a permanent electric field in other materials that form spin-density waves, such as certain organic molecular crystals. [M][J][N][O][S]
Strength of nacre Mother-of-pearl, or nacre, is 3000 times more resistant to fracture than its components, and understanding this could lead to new types of engineering materials. Nacre is made mostly of tablets of a calcium carbonate crystal called aragonite, arranged in 500-nanometre-thick layers. The iridescence of mother-of-pearl comes from the interference of light as it reflects from the thin, crystalline layers. Using an x-ray technique, researchers have now determined the orientation of the crystalline structure. They found that adjacent tablets can have different crystal orientations, even though their faces are parallel and stack neatly together. Groups of up to 40 tablets with identically oriented structures tend to form ragged columns within the sample. Cracks are less likely to propagate through the structure because they run into crystal boundaries. [M]
Self-healing material Researchers at the University of Illinois have developed a polymer-based system that can heal itself when it becomes damaged. The material relies on an underlying network of vessels - similar to blood capillaries - that carry a healing agent to areas on the material's surface that become damaged. Previous self-healing systems have relied on capsules of agent buried in the polymer, which became depleted after one use. The new system can repeatedly repair damage up to seven times at the same spot. [M]
Laser-controlled mixing When fluids are confined to small volumes, they flow slowly and smoothly with little turbulence, so it is hard to mix them together. However, Dutch and US scientists have now shown that fluids travelling through microchannels can be mixed by being whipped into a laser-induced froth by nanosecond laser pulses. The pulses create bubbles that implode, creating shockwaves that produce the rapid mixing. The technique may provide a simple way to control chemical reactions in a lab-on-a-chip, doing away with the need for pumps, valves, or complicated channel patterning. [M][J][N][O][S]
Hydrogen storage Using computer simulation, scientists in Greece say they have found a way to make so-called carbon nanoscrolls store more hydrogen than any other material. The simulations show that by adding impurities to rolled sheets of carbon, it should be possible to control how tightly the scrolls wind up and, hence, how much hydrogen they adsorb. They predict that adding lithium ions should increase the uptake of hydrogen at atmospheric pressure and room temperature from 0.19 percent to 3.3 percent. [M][N][E][P]
Enzyme action Research at the University of Buffalo has unravelled part of what makes biological enzymes so much more effective than most synthetic catalysts. Enzymes are proteins with molecular weights ranging from 10,000 to greater than 1,000,000 Daltons. In comparison, a weight of 1000 would be quite large for a synthetic catalyst and this means that so-called “catalytic” recognition is limited in man-made catalysts to just several atoms that participate in the chemical reaction. The much larger size of enzyme catalysts means that they have domains that interact with non-reacting parts of the substrate as well as with the reacting region. A flexible loop on the enzyme wraps around the substrate, burying it in an environment that is favourable for catalysis. The researchers showed that these interactions are critical to making reactions faster. [M][G][N]
Recycling with microwaves A US company, Global Resource Corporation, has developed a machine that uses 1200 different microwave frequencies to recycle plastic waste back into oil and gas. Each frequency acts on a specific hydrocarbon material. An initial application of the machine is to process so-called autofluff left over after a scrapped car has been shredded and the steel extracted. Autofluff contains a mix of plastics, rubber, wood, paper, fabrics, glass, sand, dirt, and various bits of metal. [M][E] |
||
| [E] Environment, transport and marine | |
|
|
|
|
|
Ice nucleation Using scanning tunnelling microscopy and theoretical modelling, researchers in the UK and Germany have made a breakthrough in understanding how ice forms. They imaged the "cyclic water hexamer" – or so-called smallest piece of ice – in the most detail ever. The result provides information on ice nucleation at the molecular scale and could help in understanding how ice forms around dust particles to form clouds in the upper atmosphere. [E][M]
Ocean temperatures An apparent discrepancy between climate models and ocean temperatures measurements seems to have been resolved. The measurements showed substantial variability in ocean heat content on interannual-to-decadal time scales. Using 13 numerical climate models, researchers at Lawrence Livermore have now shown that the variability can be explained by accounting for changes in observational coverage and instrumentation and by including the effects of volcanic eruptions. [E][C][P]
Soot and Arctic melting Carbon dioxide is not the only important mechanism causing melting of the Arctic, according to researchers at UC Irvine. They calculate that the darkening of snow caused by soot released into the atmosphere from smokestacks, tailpipes and even forest fires and falling onto the ground could explain one third or more of the Arctic warming. In the past two centuries, the Arctic has warmed about 1.6 degrees. The researcher's model indicates that dirty snow has caused somewhere between 0.5 and 1.5 degrees of this warming. Previous studies have analyzed dirty snow’s effect on climate, but this model is the first to take into account realistic emissions from forest fires in the Northern Hemisphere and how warming affects the thickness of the snow pack. The results suggest that simple steps, such as fully burning fossil fuels in more efficient engines and using cleaner-burning cooking stoves, could help preserve the dwindling Arctic snow cover and ice. [E][P]
Water from icebergs As the world runs short of fresh water, icebergs could be one of the answers. There are ideas and blueprints for many ways to obtain drinking water from them. Two are claimed to be quite practicable. One envisages powerful tugboats getting smaller icebergs, up to 0.1 cu km, in tow. The catch must be wrapped in protective film for transportation to prevent the ice from thawing en route. The other method envisages icebergs broken up just where they are found, to deliver granulated ice to the consumer by tankers. [E][D]
Marine ecosystems Europe's seas are in serious decline from coastal development, overuse of fertilisers, chemical pollution and over-fishing, according to a new study. The Baltic Sea is projected to suffer most, in part because its enclosed nature means that there is little tidal flow to flush out harmful substances. Also, the sea is surrounded by some of Eastern Europe's fastest growing economies, which are exerting increased pressure on the environment. [E][X]
Climate change and China As it takes over from the US as the world's top carbon emitter, China has unveiled its first national plan for climate change, saying it is intent on tackling the problem but not at the expense of economic development. The 62-page report reiterated China's aim to reduce energy use by a fifth before 2010 and increase the amount of renewable energy it produces. It also repeated Beijing's view that responsibility for climate change rests with rich westernised countries. [E][P]
Nitrogen pollution and tree growth Nitrogen from human activities such as driving cars and farming is fertilising tree growth and boosting the amount of carbon being stored in forests, according to researchers at the University of Bologna. They studied 20 clusters of forests, from Alaska to Italy, and Siberia to New Zealand, to see how much carbon they are storing and what is driving their growth. After correcting for effects depending on tree age, they found that despite the large variability between the forests in tree type and climate, there is a surprisingly good correspondence between carbon storage and nitrogen deposition. On average for every kilogram of nitrogen that is deposited on the forest floor (by rainfall, for example), an extra 400 kg of carbon dioxide is absorbed. The findings do not apply to tropical forests, where other nutrients such as phosphorus may play more critical roles than nitrogen in limiting tree growth. [E][P]
Missing carbon sink Northern forests are less effective than tropical forests in reducing global warming, according to research by NCAR. The study analyzed air samples that had been collected by aircraft across the globe for decades but never before synthesized to study the global carbon cycle. The samples show that northern forests take up only 1.5 billion tons of carbon a year, which is almost 1 billion tons less than the computer models had estimated. Instead this carbon is being taken up in the tropics by intact tropical ecosystems. This finding emphasises the importance and urgency of preserving tropical forests. [E][P][R] |
||
| [R] Remote sensing and sensor systems | |
|
|
|
|
|
Monitoring tropical forests Using NASA satellite images, scientists have documented a sharp expansion in logging roads in the tropical forests of Central Africa. An estimated 30 percent (more than 600,000 square kilometres) of the Central African forest has now been apportioned for logging and only 12 percent is protected by conservation laws. The researchers say that their research demonstrates the utility of using satellites to monitor deforestation as it "provides a consistent approach to monitor both legal and illegal" logging activities. [R][E]
Human rights monitoring by satellite A pioneering AAAS programme that provides technical expertise to human rights groups is helping Amnesty International with a new online effort to monitor threatened settlements in the war-torn Darfur region of Sudan and to provide evidence of destroyed villages. The project is at the forefront of efforts by human rights groups to use satellite cameras to help protect vulnerable populations. It will allow computer users around the globe to visually track the status of settlements that Amnesty International thinks are possible targets of attack. [R][D][E][K]
Tracking Earth's centre of mass Satellite measurements show that global sea levels are currently rising at about 3 mm a year, but the precise amount has been uncertain because of uncertainty about how much the Earth's centre of mass is moving. The Earth is constantly changing shape because of tectonic and climatic forces. A NASA study has now developed a new technique that can estimate Earth's centre of mass to within 1 mm a year by precisely positioning sites on Earth's surface using a combination of four space-based techniques. The results will not only enable sea levels to be measured more accurately but also be helpful for measuring post-glacial rebound and plate motions along fault zones, which will improve understanding of earthquake and volcanic processes. [R][A][E][P]
Better global timekeeping Highly accurate global timekeeping is critical to a number of important systems, including telecommunications, satellite navigation, navigation of space probes within the solar system, and radio astronomy using long-baseline interferometry. This timekeeping depends on caesium fountain atomic clocks. These suffer from frequency shifts caused by atomic collisions in the fountain, which have to be averaged out, and this averaging limits the rate at which time measurements can be made. Researchers at NPL, NIST and PTB have now discovered that the frequency shift can be either positive or negative depending on which of two states the atoms are in. This discovery means it should be possible to operate a caesium clock at the point of zero shift, enabling the time measurements to be made ten times faster. [R]
Lunar radio astronomy The far side of the Moon is one of the most radio quiet places in the solar system, because it is permanently shielded from the Earth's radio emissions. It would therefore be an idea place to locate a low frequency radio observatory that could work in the 1 to 10 MHz range, where radio astronomy is totally impossible on Earth. Working at these low frequencies, the observatory could map out structures prevalent in the early universe, probe the interiors of planets orbiting other stars, and possibly discover the mysterious sources of cosmic rays from their associated radio emissions. It is proposed that the observatory could be built by robots, laying out antenna-bearing strips on the Moon's surface. Ideally, astronomers would like an antenna 10 km or even 100 km across. [R][A]
Hunt for exoplanets Astronomers have demonstrated a new data-processing technique that exploits diffraction to retrieve the spectrum of stellar "companion" objects such as exoplanets from the glare of the parent star. It gives a hundred times finer spatial resolution than was previously possible. The idea, proposed in 2002, involves looking at how the Airy rings grow as images are taken at increasing wavelength. If a bright area remains in the same place as the wavelength is changed, this indicates a companion object, and by subtracting the part of the image containing the spreading rings an image of the companion object is left. The astronomers proved the technique on a four-star cluster by using the integral field spectrograph on ESO's ground-based Very Large Telescope. This can record a 2D map of a star's light at 1000 wavelengths. But to hunt for exoplanets, astronomers will have to wait until the next generation of "extreme adaptive optics" instruments are completed for existing ground-based telescopes. [R][A][C][O]
Gravitational waves and black hole mergers The Laser Interferometer Space Antenna (LISA) is designed to be sensitive to low-frequency gravitational waves with periods of between 100 and 1000 seconds, of the sort expected from colliding supermassive black holes. Such collisions should be quite common, according to new computer simulations. Most, if not all galaxies, probably contain supermassive black holes at their galactic centres. Galaxies often collide and merge - as the Milky Way will do with Andromeda in about 3 billion years time. But it is rare to find a galaxy with more than one supermassive black hole. So it is assumed that the black holes in colliding galaxies must also merge. The computer simulations suggest this is caused by drag from dense gas, which makes the two black holes spiral together. When they are close enough, their interaction generates gravitational waves that carry energy away and force the final merger. This finding is promising news for LISA, which could be launched as soon as 2015. [R][A][F] |
||
| [S] Sensor devices | |
|
|
|
|
|
VIRGO gravitational wave sensor The Franco-Italian VIRGO laser interferometer has started scientific operations searching for gravitational waves in the frequency range from 10 to 6,000 Hz. VIRGO is located in Pisa and consists of two perpendicular arms, each three kilometres long. Multiple reflections between a series of high quality mirrors extend the optical length of each arm to 120 kilometres. To reach the extreme sensitivity required and to avoid seismic noise, each optical component is isolated from ground motions at a height of 10 metres. Furthermore, as the presence of any residual gas would affect the measurements, the light beams travel in ultra high vacuum. [S][F][O][R]
T-wave imaging An article in IEEE Spectrum reviews progress towards tera-Hertz imagers. These would work at higher frequency than the mm-wave imagers of the sort made by companies such as QinetiQ, and would thereby provide higher resolution images. They may also be able to detect explosives and other suspicious material spectroscopically. Unfortunately, generating and detecting T-rays is difficult and T-waves are also strongly absorbed by the atmosphere except in a few narrow windows. One sensitive imaging approach exploits the way T-rays interfere with one another. Another converts the T-ray signal into the infrared, where it can be viewed with a digital camera. Microwatts of T-wave power tuned to an atmospheric window can be generated by mixing laser beams in an antenna-equipped semiconductor. And, in the near future, quantum cascade lasers may provide T-ray sources that are compact, cheap and bright enough for imagers to give good performance and detect explosives spectroscopically, at least at short range. [S][A][D][J][M][N][O][R][T]
Nanosample NMR Researchers in France have made a breakthrough in nuclear magnetic resonance (NMR) spectroscopy that allows the technique to be used effectively on nanolitre-sized solid samples for the first time. The new method, called magic-angle coil spinning, involves the use of two coils -- one stationary and one rotating at up to 70 kHz. It achieves much better signal to noise and could be used to study tiny biological samples such as cell cultures and forensic evidence. The researchers claim the approach could eventually be used to study chemical processes in a single biological cell. [S][B][G][H][N]
Photoacoustic imaging of inflamed cells Many research groups are investigating how to use nanoparticles to enhance imaging. One team at the University of Michigan has shown that gold nanorods can be used to observe inflamed cells in vitro using photoacoustic imaging. If demonstrated in vivo, the method could be used to monitor cell inflammation in a variety of diseases, including rheumatoid arthritis, and brain and heart disease. The technique works by attaching antibodies to the nanorods that bind to ICAM-1, a biomarker of inflammation on the surface of the inflamed cells. Near-IR laser light is able to penetrate quite deeply into tissue and is strongly absorbed by the gold nanorods. This causes local heating, which generates an acoustic pulse that can be imaged with the same resolution as ultrasonic imaging. The technique can image deeper inside tissue and at higher resolution than methods that just use light alone. It might also be used to image tumours by using nanorods with tumour antigens attached. [S][B][H][N][O][R]
Holographic imaging of molecules A breakthrough by Swiss scientists means it should soon be possible to make 3D holographic images of individual molecules, including proteins and other biological molecules whose structure is key to understanding their function. Current techniques rely largely on crystallography, which involves arranging many molecules to form a crystal structure and using high energy beams, such as x-rays, that can damage the molecules. Making holograms of individual molecules using a low-energy electron beam would avoid both problems, but attempts to do this have until now been plagued by a double-image problem in which the primary holographic image is obstructed by an out of focus secondary image. The researchers have overcome this with a computational technique that iteratively removes the secondary image. The technique has so far been tested using optical holograms, but it should also work for electron-beam and x-ray holograms. [S][C][G][H][R]
Fluorescent imaging Fluorescent imaging of single molecules in live cells is uncovering details of gene expression, structural proteins, and molecular motors. Single-molecule methods are well-established for in vitro measurements. But now scientists are using these tools to probe live cells, where they can see biological molecules in context. The most common biological single-molecule experiments involve attaching a fluorescent probe to the molecule of interest. Probes are being improved to make them it does not perturb the system, is bright and long-lived so it can be seen above the cell's background fluorescence for a long time, and is easily delivered to the molecule of interest in its natural environment. Unfortunately, no currently available probes meet all these criteria, so scientists are making do with what they have and improving probes for the future. [S][B][G][H][J][N][T]
Nanowire laser and near-field imaging Researchers at Lawrence Berkeley and UC Berkeley have devised a new type of microscopy that uses a nanowire laser to image objects with a resolution less than the wavelength of the probing light. They used the technique to image a glass plate covered with gold lines just nanometres in width, and say the technique could potentially be used to study biological samples in water. Their nanowire laser emits tuneable coherent light across the visible spectrum. The nanowires, several microns long and 50nm in diameter, are made of potassium niobate. A beam from an infrared laser is used as an optical pump and to create an optical trap in which individual nanowires can be manipulated. The nanowires can be used to touch an object as well as illuminate it in the near field, making it feasible to manipulate a specimen at the same time as visualising it at subwavelength resolution. The technology might also be used in nanophotonic circuits and cyber cryptography. [S][I][J][N][O][R]
Flexible hydrogen sensor Single-walled carbon nanotubes (SWNTs) make good sensors. This is because their electronic properties, such as capacitance and resistance, change significantly as they are exposed to small amounts of target molecules. Researchers have already made SWNT sensors that can detect nerve agents, explosives, environmental pollutants and hydrogen with high sensitivity. Now researchers at Argonne National Laboratory have made flexible SWNT hydrogen sensors. They are cheaper and perform better than their rigid counterparts, and will be particularly useful when sensors need to be wrapped around a surface, such as in vehicles and portable electronics driven by hydrogen fuel cells, and for detecting hydrogen leaks on rockets and spacecraft. [S][A][E][N][P] |
||
| [O] Optoelectronics, optics and lasers | |
|
|
|
|
|
Liquid optics The first liquid camera lens that has no moving parts and can switch between two levels of magnification, has been designed by a German research team. The design consists of four liquid lenses and three fixed plastic lenses. When the four liquid lenses are at their most curved, the optics gives a magnification of 2.5 times. When all four lenses are at their flattest there is no magnification. This is an important step towards liquid zoom lenses that can sweep through a range of magnifications. [O][I][M][S][U][V]
On-chip optical devices Researchers at Caltech have converted infrared light to visible light on chip with power levels of less than a milliwatt, much less than is normally needed for nonlinear conversion. They used a microresonator in the form of a tiny glass donut only tens of microns across. This accumulates infrared power so that an input of a milliwatt of infrared sustains an internal power of 300 watts. The infrared is trapped inside the resonator but power can escape as visible light when three infrared photons combine into a single photon of tripled frequency. The researchers say that the technique works over a wide frequency range and could provide a way to generate UV, and tuneable UV, on a chip. [O][J][S]
Photonic-crystal nanolaser Scientists at Yokohama National University have built a highly efficient room-temperature nano-scale laser that produces stable continuous output in the near-infrared. The laser's small size and efficiency were made possible by drilling a repeating pattern of holes through the GaInAsP laser material to make it into a photonic crystal. The researchers deliberately introduced an irregularity into the pattern, and the combination of the photonic crystal and the irregularity prevented light waves existing in the structure except within a small band of frequencies in the region near the irregularity. Operated in a high-Q mode, the nanolaser will be useful in optical integrated circuits. In a moderate-Q configuration, it needs only an extremely small amount of external power to bring it to the lasing threshold. In this near-thresholdless operation, it will permit the emission of very low light levels, even single photons. [O][J]
Acoustic surface plasmons Researchers at the University of New Hampshire have experimentally proved the existence of acoustic surface plasmons, a type of electron wave on metal surfaces (like waves on a pond) that was predicted theoretically but has proved very elusive experimentally. The discovery is relevant to nano-optics, high-temperature superconductors, and the fundamental understanding of chemical reactions on surfaces. Acoustic surface plasmons excited by light diffracted off nano-features may have applications in nano-microscopy and optical signal processing. The plasmons could carry optical signals along nanometre-wide channels for up to few microns, thereby allowing integration of optical signal propagation and processing devices on nanometre-length scales. Acoustic plasmons may also be involved in the electron-pairing in the two dimensional sheets inside high temperature superconductors, which produces their superconductivity. [O][C][J][M][N][S]
Femtosecond all-optical magnetic recording Dutch scientists have demonstrated all-optical magnetic recording. Instead of using the customary magnetic read head to flip the magnetic orientation of a tiny domain they use the magnetic field and heating from a 40 femtosecond (fs) pulse of circularly polarized light. The bit can be reversed with light of the opposite polarization. [O][C][J][M] |
||
| [I] IT, communications, networking and secure systems | |
|
|
|
|
|
Wireless power Induction is widely used at close range to charge mobile electronics, such as electric toothbrushes. Researchers at MIT have now developed a technique to do this at long enough range to charge something like a cell phone on the other side of a room. The trick is to design the radiating coil so that most of the oscillating electric field is trapped inside it and to use just the oscillating magnetic field to transfer power through resonant coupling. A magnetic field does not interact with most objects, including biological tissues, which is crucial for safety. [I][P]
Cellphone use approved in flight The European Aviation Safety Agency has given approval for airliners to be fitted with the OnAir technology to make cellphone calls in flight. The OnAir system overcomes the problem that during flight cellphones might emit their maximum limit of electromagnetic radiation as they attempt to communicate with distant towers on the ground. Instead, the cellphone connects to an OnAir system on board the aircraft. This then relays the link via satellite. [I][A]
Internet data neutrality As the Internet becomes more crowded with high-bandwidth applications and content, there is debate about whether to continue to treat all data identically or whether traffic that requires performance assurances, such as VoIP, should be serviced differently. The debate is wide-ranging and controversial, and involves both economic and technical issues. A new study by researchers at Rensselaer Polytechnic, AT&T Labs, and the University of Nevada has compared the current “best-effort” undifferentiated approach with a tiered model that differentiates information into two simple classes - one for most types of information and another for applications requiring service level assurance for high-bandwidth content like video games, telemedicine, and Voice over Internet Protocol (VoIP). The results suggest that even for modest loading the "required extra capacity" for an undifferentiated network could approach 60 percent, and at times of heavy demand it could amount to 100 percent or more of the total capacity required when differentiation is permitted. [I][K][V]
Anti-virus software Researchers at the University of Michigan report that tests on five leading anti-virus programs showed they could identify only between 50 and 80 percent of a large sample of malware and did not always agree on their identification. Identifying previously unknown malware is difficult, and keeping track of different variants of existing viruses makes this harder. For example, a virus called Agobot has split into more than 580 variants since its release in 2002. The researchers have developed an alternative approach that uses the "fingerprint" of virus activity to identify them, grouping those that may appear different but work in the same way. They claim that tests show this approach works better than conventional anti-virus software that looks for suspicious behaviour and for code from known viruses. [I]
The Athens affair The July issue of IEEE Spectrum includes a case study of how some extremely smart, and still unidentified, hackers broke into a GSM telephone network in Greece and subverted its built-in wiretapping features. This allowed them for many months to listen in to the telephone conversations of Greece's most senior ministers and officials, including the Greek Prime Minister. The article describes what is known about how this penetration was effected technically, how the hackers evaded detection for so long until they made a slip in updating their rogue software in January 2005, why they got away, and what lessons can be learned for better cyber security. [I][C][T] |
||
| [K] Knowledge, information and technology management | |
|
|
|
|
|
Map-based information Geocentric Web interfaces such as Microsoft Virtual Earth and Google Maps are useful for visualizing spatially and geographically related data such as driving directions, directory entries, and weather and traffic conditions, to name a few. An article in IEEE Computer describes work at Microsoft Research on its SensorMap portal - a new application that uses real-time sensor data and its mash-up with the geocentric Web to provide instantaneous environmental visibility and timely decision support. Collecting and presenting continuously changing and diverse types of data pushes the limits of current Web technologies, particularly in aggregating data from vastly different sensors and services on a shared Web portal, discovering available sensors on the web, managing such large amount of data and presenting the output to users. To realise its full value, the portal also needs to be easily extensible and mashed up with other applications and services. [K][C][D][E][I][R][V][W][X]
Social networking Some social networking sites now use satellite positioning to track users' whereabouts so that friends, colleagues or relatives can see where they are. Social networking is also showing evidence of class divide, at least in the US where a recent study found that those using Facebook come from wealthier homes and are more likely to attend college compared with MySpace users. In the UK, the scale and age range of social networking is continuing to expand. According to an independent net monitoring firm, MySpace had 6.5 million unique UK visitors in May 2007 and Facebook and Bebo are both rapidly catching up. [K][I][V]
Growth of on-line advertising The annual value of pan-European online advertising is set to reach around 16bn euros ($22bn; £11bn) by 2012, more than double that of 2006, according to a report by research body Forrester. European internet users now spend 14.3 hours a week online, compared with 11.3 hours watching TV, and 4.4 hours reading newspapers or magazines. The report said search engines would continue to dominate online advertising spend, followed by display advertisements and e-mails. [K][I][V]
Predicting insurgency According to research at the University of Maryland, computers can be programmed to automatically and quickly extract relevant data from thousands of news reports on a topic and offer a probability estimate that a particular action might happen. The research, funded by the US DOD, is part of an effort to understand better the potential cultural, religious and social impact of insurgency and military actions in combat zones. Such computer tools could help analysts to assess the emergence of insurgent groups, how they interact with the local population and how they might respond to military or economic interventions. [K][C][D][X]
Public information strategy The UK Prime Minister's Strategy Unit has published an independent review of the way information is used, the power that it has, the role of the internet, and what this means for government. The review examines the social and economic benefits from new ways of making and sharing information, whether involving government, citizens or both. It argues that government could now grasp more vigorously the opportunities that are emerging in terms of the creation, consumption and re-use of information. It makes recommendations on exploring opportunities, improving access to public sector information, and protecting the public interest. [K][T]
European R&D A European Commission report comparing R&D in the EU with that of its competitors notes that Europe still suffers from the problem that it is good at producing knowledge but has a serious weakness in exploiting knowledge and in the impact and flow of knowledge to business. The EU is still failing to increase spending on research as a percentage of GDP, particularly by companies. The changes in economic activities in countries such as China and South Korea mean that US companies are now targeting Asia and other regions for outward R&D investment. As a result, the EU's share of America's outward R&D spend has been declining since the mid-nineties. In the UK, however, which is a choice location for R&D activities, R&D rose by over 11 percent in 2006. [K][T][W] |
||
| [C] Computing, supercomputing, modelling and simulation | |
|
|
|
|
|
Petaflop supercomputer The world's first supercomputer with petaflop performance has been announced by IBM. Called Blue Gene/P, it will be capable of a peak performance of 3 petaflops (3000 million million floating point operations per second), and its sustained performance is expected to level out at around 1 petaflop. The first Blue Gene/P machine will be installed at Argonne National Laboratory later in 2007 and will be used primarily to perform nuclear weapons simulations. Other systems will then be installed in Germany, the UK and elsewhere in the US. Blue Gene/P is the third of the planned series of four Blue Gene computers. The last, Blue Gene/Q, is aimed to reach 10 petaflops in the 2010-2012 time frame. The Blue Gene computers are being used chiefly in weapons research, radio astronomy, protein folding, climate research, cosmology, and drug development. [C][D][E][G][X]
Massively parallel PCs Researchers at the University of Maryland have developed a prototype highly parallel personal computer that is capable of computing speeds 100 times faster than current desktops. It uses 64 parallel processors, the sort of capability that will be available on future single chip multi-core processors. To control those processors, they have developed a parallel computer organization that they claim allows the processors to work together and makes programming practical and simple for software developers. [C][J][W]
Superconducting qubit gate There are many quantum computing candidates, with differing advantages and disadvantages. In order for a system to be a good candidate, it should be a scalable physical system with well-defined qubits, be initialisable, have long decoherence times, have a universal set of quantum gates, and permit qubit-specific measurements for readout. One promising approach involves superconducting electrodes coupled through Josephson junctions. This approach is very easy to initialise, should in theory have a long coherence time, and, being solid state, should be scaleable to large numbers of qubits and allow mass fabrication. An important issue has been how to couple superconducting qubits together. Researchers at Delft have now taken an important step forward by linking two superconducting rings to work as a ‘controlled-NOT’ gate. [C][J][N]
Optical lattice Researchers at Pennsylvania State University have made an important step towards building a quantum computer with a large number of qubits. Using three lasers arranged at right angles they created a 3D lattice in which they were able to trap and individually observe 250 atoms of caesium. [C][O]
Optical quantum computing One way to produce a quantum computer could involve entangled photons moving from node to node in an optical system – with the nodes performing logical operations on the photons. This requires a way of transferring quantum information from the entangled photons to the nodes and vice versa, and also a way of generating entangled photon pairs and sending them off in the appropriate directions. Researchers at Max Planck and Oxford University have made an important step towards this by developing a way to entangle photon pairs using a single atom. The team first fired a laser pulse at a rubidium atom trapped in an optical cavity, causing the atom to emit a single photon. As a result of this process, the atom and the photon were entangled. A microsecond or so later, a second laser pulse was fired at the atom, causing it to emit a second photon and also causing the entanglement to be transferred from the atom to the second photon, thereby creating the entangled pair. [C][I][O]
Cosmic simulation An international team has for the first time incorporated the physics of black holes into a computer simulation of cosmic evolution. Astronomical observations show that black holes are important regulators of galaxy formation and, ultimately, of the structure of the universe. But previous simulations did not take black holes into account because the computing demand was prohibitive. The new simulation resolves spatial scales that range from structures inside a single galaxy to the filamentary structures that the galaxies inhabit, which are tens of millions of light years long. As well as showing how the galaxies and clusters develop and how supermassive black holes evolve, the simulation can also help astronomers by predicting what next-generation telescopes should see as they peer back 13 billion years to the time just after the Big Bang. [C][A][F][R] |
||
| [W] Whole life engineering, manufacture and testing | |
|
|
|
|
|
Software and security standards Two articles in July IEEE Computer discuss the use of computing standards. One looks at the process of creating, using and harmonising standards. The other looks at the balance in the case of security standards between mandating standards strictly and retaining flexibility to keep down costs and to respond quickly to changing threats. [W][C][D][I][K][T]
Change tolerant systems As software systems continue to become bigger and more complex, they are progressively more difficult to understand and evolve. Their complexity often exceeds human comprehension. Traditionally, software engineers handle complexity by decomposing systems into manageable parts to accommodate the sheer number of elements and their structure. However, the Internet and the emergence of software as services have led to a new kind of complexity that arises from an increase in both the number and intricacy of system interactions, and likewise the trend towards autonomic and self-healing systems. So software must be change tolerant. Automated support for analyzing and visualizing software impacts and navigating software artefacts are no longer a luxury. Understanding software impacts makes it easier to design, implement, and change software: tradeoffs become clear, ripple effects become more certain, and estimates become more accurate. [W][C][I][K][U][V][X]
Improving field service productivity In recent years, much thinking has focused on ways organisations can improve the productivity of their invisible employees, who work in the field, remotely, out of view, often at their own pace, in industries such as telecommunications and courier services. Productivity metrics and reports that tell executives only what happened in the past, miss the opportunity to make improvements. Now, however, according to McKinsey, some companies are using new technology to get a more timely and accurate view of the field force, so managers can make decisions as events unfold. This approach uses real-time information flows from the field, combined with the statistical analysis of consumer demand for services. These changes can dramatically improve productivity by raising the number of assignments that field technicians can undertake in a typical day, reducing wait times, and improving customer service. [W][D][E][I][K][X] |
||
| [X] Systems, complexity and risk | |
|
|
|
|
|
Predicting hurricane risk In 2005, three "hurricane-hunter" planes, one equipped with Doppler radar, flew repeated missions into the cores of hurricanes Katrina, Ophelia and Rita and collected unprecedented data on the structure, configuration, and interaction of clouds in the storms. The data was combined in real time with simultaneous satellite observation, and high resolution simulations of the hurricane were then used to direct the pilots toward parts of the storm where interesting features were present or likely to appear. This enabled an aircraft for the first time ever to directly observe a ring of intense thunderstorms just outside the storm's eyewall. Such secondary eyewalls, which appear to have significant effects on hurricanes' strengths, had often been detected by satellites and radar but had never before been seen in the fine detail. The hope is that the increasing understanding of hurricanes from these and future missions will make it possible to predict more accurately the peak strength of each hurricane and the risk that it poses. [X][A][C][D][E][R][T]
Environmental risks The World Health Organization (WHO) has released the first ever country-by-country analysis of the impact environmental factors have on health. The data show huge inequalities but also demonstrate that in every country, people's health could be improved by reducing environmental risks including pollution, hazards in the work environment, UV radiation, noise, agricultural risks, climate and ecosystem change. [X][E][H][P][W]
Synthetic biosystems Synthetic biosystems have considerable technological and industrial potential. They might, for example, be used to produce pharmaceuticals or to create synthetic prosthetic networks of cells to replace damaged natural networks in the human body. A key aspect in designing such systems is their communication mechanism. Natural multicellular organisms use hormones to communicate. Bacteria use other signalling chemicals, called pheromones by analogy with insect pheromones, that enable large numbers of bacteria to act in a co-ordinated fashion - to form a biofilm for example. Researchers at the Swiss Federal Institute of Technology are experimenting with different communication mechanisms. They have engineered an airborne communication system that relies on mammalian cells to convert ethanol to acetaldehyde. The acetaldehyde evaporates at 21 degrees C and travels to receiver cells, where it triggers various cellular processes. The system can work either for cells in culture or in vivo in actual mice. [X][B][G][H][M][N][V]
Altruism versus egoism Understanding why people do things for the common good and how to foster such altruism are relevant to tackling major problems such as climate change that require collective human action as well as for taxation policy and encouraging the voluntary sector. Using fMRI to monitor the brains of people playing games designed to explore altruism, researchers have discovered that people have similar brain activity - and feel rewarded - no matter how they fund the public good, whether giving to charity or paying taxes. This runs counter to most economic theories, which are based on the notion that people almost always act out of self-interest and not out of concern for the welfare of others. The researchers showed they could reliably predict just from their brain activity how subjects were going to behave. Altruistic subjects showed more pleasure-related brain activity when they were forced to pay taxes than when they received random financial "payoffs.' For egoists it was the reverse. [X][B][D][E][H]
Altruism and co-operation A new study has shown that chimpanzees, as well as 18-month-old children, will assist strangers even when getting no personal reward. In several different experiments, the chimpanzees assisted experimenters and other chimpanzees that they neither knew nor were related to, without any offer or receipt of reward and when, in one experiment, giving assistance required them to go to the effort of climbing a 2.5-metre-high platform. Whilst the results may come as no surprise to field workers familiar with chimpanzees in the wild, they suggest that human altruism has deep evolutionary roots. [X][B][D][E][G][W] |
||
| [V] Virtuality and human-machine interface | |
|
|
|
|
|
Talking paper Swedish researchers have developed an interactive paper billboard that emits recorded sound in response to a user's touch. It uses a layer of digital paper that is embedded with electronics and is printed with pressure-sensitive conductive inks. These detect the user's touch and also form the printed speakers, which are made from layers of conductive inks that sit over an empty cavity to form a diaphragm. The researchers envisage that the technology could be used to make interactive advertisements and signs, and possibly eventually used for product packaging. [V][M][S]
Virtual contact A system that makes three dimensional images solid enough to grasp has been unveiled by Japanese firm NTT. It combines a 3D display with a haptic glove and could let people shake hands from across the globe or allow museum visitors to feel precious exhibits that are normally out of reach. [V]
Exploiting immersive virtual reality In some applications of immersive virtual reality (IVR), experiencing a computer-generated world as if it were real (presence) is all important. These include military or medical training, where the goal is to cause the trainee to do the right thing when faced with situations in the real world, and treating phobias, where the goal is to trigger the brain's fear structures. In other applications, presence is not important, but IVR gives a fuller understanding of a situation. An example is the way that the oil and gas industry uses IVR to visualize and plan underground oil well paths. IVR makes it easier to view and understand complex 3D structures to make correct decisions. Immersion can reduce information clutter, increase the useful information bandwidth to the brain, and raise peripheral awareness and spatial understanding. This can result in greater effectiveness for many applications such as scientific visualization, design review, and virtual prototyping. Current research is investigating which components of immersion are most beneficial for which applications. [V][C][D][E][G][H][K][T][W][X]
Bionic hearing Around 100,000 people world wide have been fitted with cochlear implants to restore hearing. The implants work by sending electrical signals to a set of electrodes coiled into the cochlea – the spiral organ in the ear that senses sound. However, it is difficult to insert the electrode array beyond the outer turns of the cochlea - the part that picks up the high frequencies - and therefore the implants work poorly at low frequencies, and the signals are also blurred by having to travel through liquid in the cochlea and then through its bony wall to the nerves outside. Now, researchers have developed a new type of implant that bypasses the cochlea and instead connects directly to the nerves. Tests on cats show that the new device dramatically improves the range of tones that can be heard. [V][B]
Neuro-memory Researchers at Tel Aviv University have demonstrated that neurons cultured outside the brain can be imprinted with multiple rudimentary memories that persist for days without interfering with or wiping out others. This brings closer the creation of "cyborg" computer chips that combine electronic circuits with human cells. Previous attempts to develop memories on brain cell cultures have often involved stimulating the synapses. However, this upsets the existing firing patterns in the network causing the existing memory to be corrupted. Instead, the Israeli researchers stored the memory patterns by disabling inhibitory neurons. These inhibitory neurons make up about 20 percent of the neurons and dampen the activity of the so-called excitatory neurons that make up the remaining 80 percent. The researchers were able to establish patterns of neural firings that repeated for more than a day, and by disabling different inhibitory neurons they could superimpose new long-lasting firing patterns that, surprisingly, did not disrupt the previous patterns. [V][B][C][J] |
||
| [B] Brain research and human science | |
|
|
|
|
|
Brain's speech receiver A particular resonance pattern in the brain’s auditory processing region appears to be key to its ability to discriminate speech, according to researchers at the University of Maryland. In their experiments, the researchers asked volunteers to listen to spoken sentences whilst their brains were scanned using magnetoencephalography - an imaging technique that measures magnetic fields produced by electrical activity in brain regions. The researchers found that the inherent rhythm of neural activity called “theta band” specifically reacts to spoken sentences by changing its phase. They also noted that the natural oscillation of this frequency provides further evidence that the brain samples speech segments about the length of a syllable from any language. [B][V]
Short term memory Short term memory is neurologically distinct from the storage and retrieval of longer-term memories. It lasts only about 30 seconds and its basis lies in the ability of specific neurons to maintain a persistent level of activity in the absence of input. This activity is finely coordinated across related groups of cells. By studying how goldfish use short-term memory to control their eye moments, researchers have elucidated how this coordination is achieved. They found that two groups of cells are involved, one in each half of the brain. Each group contains two types of neurons - inhibitory cells and excitatory cells. The excitatory cells produce the sustained firing that working memory requires.
The inhibitory neurons allow the two groups to interact and ensure that only one group is generating persistent excitation at a time, so that there is no conflict. [B][H]
The dentate gyrus and déjà-vu The hippocampus is well-characterized as the seat of episodic memory that records times, places and events. Researchers at MIT and Bristol University have now shown that a section of the hippocampus called the dentate gyrus is responsible for distinguishing between similar but different places or experiences. Failure to do this, because the present situations is too similar to something in the past, produces the sense of déjà-vu. The researchers say that the finding may pave the way for new ways to prevent or reverse deficits in episodic memory that are caused by ageing or neurodegenerative diseases such as Alzheimer's. [B][G][H]
Brain controllers Scientists exploring the upper reaches of the brain's command hierarchy have found not one but two independent brain networks in charge. Starting with a group of several brain regions implicated in top-down control, they used a new brain-scanning technique to identify which of those regions work with each other. This revealed that the regions grouped into two networks. The regions in each network talked to each other often but never talked to brain regions in the other network. One network, dubbed the cingulo-opercular network, was linked to a "sustain" signal that is constantly active while a task is being done. The other, dubbed the fronto-parietal network was consistently active at the start of mental tasks and during the correction of errors. The researchers think that the fronto-parietal network may be the more online, rapidly adapting controller, while the cingulo-opercular network is the more stable, set, in-the-background controller. [B][C]
The brain's ancient core Hormones control growth, metabolism, reproduction and many other important biological processes. In humans, and all other vertebrates, the chemical signals are produced by specialised brain centres such as the hypothalamus and are secreted into the blood stream that distributes them around the body. It was thought that the hormone-secreting brain centres evolved after the evolutionary trees of vertebrates and invertebrates had split apart. However, new research at EMBL has revealed that they are much more ancient. The finding suggest that the brain originated as a clustering together of multifunctional sensory cells that sensed cues from the ancient marine environment and translated these into changes in the animal’s body. The researchers say that the findings change the way one should view the brain - less as a processing unit handling sensory data and more as a sensory organ itself. [B][G][X]
Evolution of the nervous system The first neurons and synapses appeared over 600 million years ago in “cnidarians,” creatures known today as hydra, sea anemones, and jellyfish. By contrast, sponges, the oldest known animal group with living representatives, have no neurons or synapses. They are very simple animals with no internal organs. However, researchers at UCSB have found that many genes that are needed to make a nervous system are also present in the sponge. Even more surprising is the finding that the sponge proteins have ‘signatures’ indicating they probably interact with each other in a similar way to the proteins in synapses of humans and mice. This suggests that the nervous system has its roots in a much more ancient structure and that evolution was able to convert this entire structure to a new function. [B][G]
Expressing emotions Brain scans show that when people see a photograph of an angry or fearful face, they have increased activity in a region of the brain called the amygdala, which serves as an alarm that activates a cascade of biological systems to protect the body in times of danger. A robust amygdala response occurs even when such emotional photographs are shown so fast that the person cannot see them. A new brain imaging study by UCLA psychologists has now shown that verbalising a feeling of anger or fear decreased the response in the amygdala. This may reveal why putting feelings into words can make sadness, anger, fear and pain less intense. The imaging also showed that a specific part of the brain - the right ventrolateral prefrontal cortex - seems to be involved in the labelling of emotion. [B][H]
Benefits of brain stimulation A study of more than 700 people in Chicago with an average age of 80, who underwent yearly cognitive testing for up to five years, has shown that those who were cognitively active were 2.6 times less likely to develop dementia and Alzheimer’s disease than those who were cognitively inactive. This association remained after controlling for past cognitive activity, lifetime socioeconomic status, and current social and physical activity. [B][H] |
||
| [H] Healthcare and medicine | |
|
|
|
|
|
Prions and Alzheimer's disease In variant Creutzfeldt-Jakob disease (vCJD), the human version of BSE, the normal version of the prion protein present in brain cells is corrupted by infectious prions causing it to change shape, resulting in brain damage and death. Researchers at the University of Leeds have now found that the normal version of the prion protein may have a role in regulating the production of beta-amyloid and may therefore protect against Alzheimer's disease. The similarities between Alzheimer's and diseases such as variant CJD has been well known, but this is the first research that has shown a clear link between prions and Alzheimer's. The hope is that if a treatment could be designed to mimic the effect of the prions it might halt the progression of the disease. [H][B]
Brain injury, stress and Alzheimer's People who suffer severe blows to the head, or a stroke or succession of transient ischemic attacks, are more likely to develop Alzheimer's disease. Researchers at Massachusetts General Hospital have now found a possible explanation. Through experiments in vitro and on rats, they discovered that caspases produced by injury to brain cells interfere with the normal disposal of a protein known as beta-secretase (BACE). BACE is a protein-cleaving enzyme that snips apart amyloid precursor protein to form A beta peptide - the building block for the amyloid plaques that are a hallmark of Alzheimer's disease. Researchers at Salk Institute have also found a possible mechanistic link between chronic mild stress and the development of the tau tangles, which are the other defining symptom of Alzheimer's. A long-term study of about 800 members of religious orders previously found that the people who were most prone to stress were twice as likely to develop Alzheimer’s. [H][B]
Towards an Alzheimer vaccine One of the main goals in developing treatments for Alzheimer's disease is to find ways to destroy the beta amyloid plaques. Antibodies produced by vaccination have been shown to be effective at removing these plaques, but how they do this has been unclear. Researchers have now clarified that the antibodies work by first connecting to amyloid precursor protein (APP) on the cell surface and being taken into the cell with the APP. Inside the cell, the APP is broken down into pieces, some of which are the amyloid beta peptide that would normally start clustering into plaque. The experiments showed that the presence of the antibodies prevents this from happening by reducing accumulation of the amyloid beta peptide in cell vesicles called endosomes. The researchers also found that the antibodies helped to restore communication between nerve cells by clearing external plaque that was interfering with the synapses. [H][B]
Vaccines against drug addiction A pair of new vaccines designed to combat cocaine and methamphetamine dependencies not only relieve addiction but also minimize withdrawal symptoms, according to new research. The vaccines stimulate the body to produce antibodies that then attack the drug while it is in the blood stream. This prevents the drug from reaching the brain and creating the reactions that contribute to dependency. [H][B][G]
Crossing the blood-brain barrier With the help of a molecule from the rabies virus, scientists have for the first time selectively ferried a drug across the blood-brain barrier to treat a neurological disease in mice. The walls of capillaries that carry blood into the brain control whether molecules larger than a few hundred atoms, such as antibodies and proteins, can pass into the spaces between neurons. This capillary barrier prevents most drugs from reaching the brain. However, some viruses, including rabies, have molecules that trick the barrier into allowing them to pass. Researchers attached a molecule from the rabies virus to a drug and found that the coupled molecules got through the capillary walls and into the brain. In trials, a drug delivered in this way kept 80 percent of mice infected with Japanese encephalitis alive for at least 30 days, while all of the untreated mice died. [H][B][G]
Destroying airborne superbugs In the 1990s, scientists at the Porton Down chemical and biological defence laboratory established that microbes in the open air are killed by hydroxyl radicals, highly reactive agents constantly produced through natural reactions between airborne ozone and organic scented chemicals from plants such as pine trees. This discovery has now led to a device that generates hydroxyl radicals in large quantities and can be used to quickly purge hospital wards of superbugs, including MRSA and Clostridium difficile. The device is being tested in UK hospitals and at 17 veterans’ hospitals in the US. [H][D]
Infectious money Flu viruses can persist on banknotes much longer than expected, according to Swiss research. Some strains lasted only two hours, but the most common flu, H3N2, lasted up to 72 hours. And, all strains lasted longer when they were dripped onto the banknotes along with human nasal mucus. Some lasted as long as 17 days. This means that banknotes could be a way that flu epidemics can spread. [H][D]
Artificial skin A long-lasting artificial skin which is fully and consistently integrated into the human body is reported to have shown promising results in early clinical trials. The skin appears to work better than other skin substitutes tried in the past, which have biodegraded in situ after a few weeks. Tests show the new membrane integrated fully by 28 days, producing a closed and healed wound site. The skin is made up of a matrix of fibrin, which is a protein found in healing wounds. Fibroblasts, the cells that produce collagen in natural skin, are integrated into the fibrin matrix. The skin will now be tested on larger wounds and burns. [H][M]
Making mosquitoes harmless An international team has identified the genes behind the immune system of the mosquito Aedes aegypti, which is responsible for transmitting the viruses which cause dengue fever and yellow fever. Between them, these diseases infect over 50 million people worldwide every year. US researchers have also discovered why some mosquitoes are resistant to malaria. The scientists hope that understanding the genetics behind pathogen/immune system interactions in disease vector mosquitoes may explain why some types of mosquitoes can transmit a particular human pathogen while others cannot. If those that cannot have evolved an effective immune system that fights off the pathogen, it may be possible to enhance specific reactions of the immune systems in other mosquitoes to control the spread of disease. [H][G] |
||