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Top Stories in Science
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| [D] Defence and security |  |
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UN Secretary-General Ban Ki-moon has urged the world to put the looming crisis over water shortages at the top of the global agenda in 2008 and to take action to prevent conflicts over scarce supplies. He reminded business and political leaders at the World Economic Forum that the conflict in the Darfur region of Sudan was touched off by drought. He said that a recent report has identified 46 countries with 2.7 billion people where climate change and water-related crises create "a high risk of violent conflict". At the "Major Economics Meeting on Energy Security and Climate Change" in Honolulu, representatives from 17 major economies plus the UN called for rapid progress in implementing the Bali roadmap. The Bush administration sponsored the meeting and said its purpose was to supplement the UN efforts in battling climate change. It denied allegations that it wanted to sidetrack the UN climate talks and push forward a US agenda instead. More than 200,000 crop varieties from Asia, Africa, Latin America and the Middle East - drawn from vast seed collections maintained by the Consultative Group on International Agricultural Research (CGIAR) - have been shipped to a remote island near the Arctic Circle to be stored in the Svalbard Global Seed Vault (SGSV), a facility in a mountain deep inside the Arctic permafrost that is capable of preserving their vitality for thousands of years. The cornucopia of rice, wheat, beans, sorghum, sweet potatoes, lentils, chick peas and a host of other food, forage and agroforestry plants is to be safeguarded in the facility, which was created as a repository of last resort for humanity?s agricultural heritage. Passport and ID card photos could be more effective if they were averages of several snapshots, according to researchers at the University of Glasgow. They have shown that this approach allows facial recognition software to spot familiar faces as well humans do. The averaging technique first identifies a face's landmarks, such as the corners of the eyes or the mouth, and uses these to align several photos. If photos show a person at different angles, the software stretches the image so that landmarks on different photos align with each other. Finally the photos are merged together. This averages out artefacts such as lighting and pose. Fighting an influenza epidemic has been made harder by the fact that almost all the dangerous type A influenza strains have become resistant to amantadine and rimantadine, two key drugs that make up one of only two classes used to treat flu. Amantadine halts influenza infection by blocking the flow of protons in a flu virus protein called M2. It fits like a cork in the M2 channel through which the protons flow. Researchers at Penn State have found that flu strains have developed resistance to amantadine because of a mutation of M2 that alters the shape of the channel so that amantadine no longer blocks it tightly. They also found there is a pocket in the channel next to the location where amantadine fits that is conserved in all influenza A viruses. This pocket could be the target for new blocking drugs. A vaccine against H5N1 influenza has been developed at the University of Pittsburgh. Unlike other avian flu vaccines, which are partially developed from live viruses, the Pittsburgh vaccine uses a virus-like particle that is recognized by the immune system as a real virus but lacks genetic information to reproduce, making it potentially safer. The vaccine also encoded proteins to protect against possible new strains of the virus. To test the vaccine, researchers administered it to mice in one-dose and two-dose regimens. Mice immunized twice with the vaccine developed protective antibodies against H5N1 and were protected from disease and death when directly exposed to the virus. MIT researchers have uncovered a critical difference between flu viruses that infect birds and humans, namely that the virus's ability to infect humans depends on whether it can bind to one specific shape of receptor on the surface of human respiratory cells. Until now, scientists had believed that a genetic switch that allows the virus to bind to alpha 2-6 glycan receptors instead of alpha 2-3 receptors is responsible for avian viruses' ability to jump to humans. However, the alpha 2-6 receptors come in two shapes, one resembling an umbrella and the other a cone. The MIT team found that to infect humans, flu viruses must bind to the umbrella-shaped receptor. This should help in monitor the evolution of avian flu strains and also help in developing a vaccine. Research to develop defence against Ebola is hampered because the virus is so dangerous that it can only be handled in category 4 containment facilities, which are scarce and highly expensive. Now, however, researchers from the University of Wisconsin-Madison have shown that the virus can be rendered safe by deleting one of its genes. The gene makes a protein called VP30 that the virus needs to replicate in host cells. This means the altered virus cannot grow in any normal cells. To study the virus, the researchers have engineered laboratory cells that themselves express the VP30 protein, and the altered virus can grow in these VP30 cells alone. In all other respects the virus is identical to the pathogen found in the wild, making it ideal for studies of basic biology, vaccine development and screening for antiviral compounds. A large national household survey conducted by the Iraqi government and the World Health Organisation (WHO) estimates that around 151 000 Iraqis died from violence between March 2003 and June 2006. This estimate is three times higher than the death toll detected through careful screening of media reports by the Iraq Body Count project and about four times lower than a smaller-scale household survey conducted earlier in 2006. More than half of the violent deaths occurred in Baghdad. |
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| [A] Aeronautics and space | |
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Virgin Galactic has unveiled models of SpaceShipTwo, the vehicle they hope will take passengers about 62 miles above Earth. The spacecraft, which will carry six passengers and two pilots, is made entirely of carbon composite materials. It will be about 18 metres long and has large, movable feather-shaped vertical fins at the back to make re-entry safer. At present the prototype is 60 percent completed and it is hoped that test flights can begin this year. The launch aircraft, White Knight Two, was also unveiled. This is a two-fuselage aircraft with a wingspan of about 43 metres. It will carry SpaceShipTwo under the centre of its wing, between the two hulls, to an altitude of around 15 km. From here, the spacecraft will rocket upward into space. The aim is to use it to cheaply launch small payloads and satellites into orbit as well as for carrying space tourists. Launched in 1990, the Hubble Space Telescope has become one of the most important instruments in the history of astronomy. To keep it operational for another decade or more, NASA is launching a Hubble-upgrade mission later in 2008. The upgrade will provide a massive boost to Hubble's capabilities, giving it 10 to 20 times greater sensitivity, much greater wavelength capabilities and a much larger field of view. Whereas Hubble could originally see only 10 galaxies at a time, the upgrade will be able it to see 900. On its first fly-by of Mercury, NASA's MESSENGER spacecraft has passed within 200 km of the planet, providing a close-up view of its surface, half of which has never before been seen close-up. Its wide angle camera has 11 narrow-band colour filters spanning the visible and infrared. Combining the colour images can reveal which features originate from the planet's thin crust and which have emerged from the mantle beneath. Laser altimetry provides high-resolution topography of the surface. MESSENGER will make two further fly-bys and then settle into a year-long orbit around Mercury beginning in March 2011. This will be followed by the ESA BepiColombo mission, due for launch in 2013, reaching Mercury in 2019. Mercury and Earth are the only two terrestrial planets in the solar system with magnetospheres produced by an intrinsic magnetic field. The MESSENGER spacecraft in its first fly-by of Mercury has found that Mercury's magnetosphere is quite similar to Earth's but has no Van Allen radiation belts. Astronomers have found a newborn planet in a solar system that is still in the process of forming. The star is about 10 million years old. So the discovery confirms that planets can coalesce within 10 million years and should help to test models of how planets and solar systems form. The planet was detected indirectly by the radial velocity (RV) method, which looks for slight oscillation in the Doppler shift of the star's light each time the planet orbits the star. This Doppler shift is caused by the planet gravitationally pulling material from the star towards itself. Plate tectonics may be crucial to a planet's habitability: it enables complex chemistry and recycles substances like carbon dioxide, which stabilises surface temperature. Astronomers have now shown that Earth is only just large enough to support plate tectonics, whilst Venus with a mass of 0.815 Earths is too small. Plate tectonics will be much more vigorous on so-called "super-Earths" - planets up to 10 times more massive than Earth. So super-Earths may be more likely to support life, provided they are at the right distance from their star to have a habitable temperature. Exoplanet searches have so far discovered five super-Earths, although none has life-friendly temperatures. The Pilbara region in Western Australia has rock layers in the shape of cones, waves and "egg carton" domes that have been dated up to 3.4 billion years old. Some palaeogeologists believe these layers are fossilised remains of bacteria called stromatolites; others believe that the shapes are the result of chemical weathering. The likelihood of a biological origin has now been supported by nanospectroscopy of deep core samples from Pilbara that show minute crystals of aragonite, a calcite residue from dead micro-organisms. If microbial life existed on Earth so early in its history, this makes it more likely that life might also have existed on Mars, which probably had an atmosphere and seas at that time. Cosmological theory predicts that spiral galaxies like the Milky Way have evolved from low-mass galaxies. Astronomers at Rutgers and Penn State universities have now discovered such ancestral galaxies around 12 billion light years from Earth, meaning they are being observed at a time less than 2 billion years after the Big Bang. They are about one-tenth the size and one-twentieth the mass of the Milky Way. The researchers also observed how such galaxies, in groups sometimes of 10 or more, pull together over the ensuing few billion years to form a single spiral galaxy. |
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| [U] Unmanned vehicles and robotics | |
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In a demonstration relevant to neural prosthetic limbs and to controlling robots remotely, a humanoid robot in Kyoto has walked like a monkey by being controlled in real time by the cortical brain activity of a monkey walking on a treadmill at Duke University in North Carolina. The monkey's brain activity was relayed over the Internet from the US to the robot in Japan. |
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| [P] Propulsion and energy | |
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The world's first commercial cargo ship partially powered by a giant kite has set off on its maiden voyage to cross the Atlantic from Germany to Venezuela. The vessel is a 122 metre diesel-powered freighter equipped with a 160 square metre computer-controlled kite flying 183 metres above its bows. The kite resembles a paraglider and is shaped like an aircraft wing to enable it to take advantage of different wind directions. The designers estimate it should reduce the annual fuel costs by 10 to 35 percent, depending on the prevailing wind conditions. Harnessing the full power of the wind under optimal wind conditions, it can halve the ship's fuel consumption. Maritime shipping produces over 1 billion tonnes of carbon dioxide per year, about 5 percent of global emissions. Highly-porous, crystalline materials called metal-organic frameworks (MOFs) are promising materials for storing fuels such as methane. Researchers say they have now developed a MOF that has a methane-storage capacity 28 percent higher than the US DOE's target for methane-powered cars. A Canadian company has developed a prototype fuel cell small enough to fit comfortably inside a cell phone. The fuel cell can last twice as long between refuelling than phones powered with lithium ion batteries. However there are issues over safety and the availability of hydrogen for recharging the cell. Most hybrid vehicles use expensive nickel-metal hydride batteries. Now, researchers have developed a much cheaper alternative, called an UltraBattery, by combining a lead-acid battery with supercapacitors. The supercapacitors are actually built into the lead-acid battery, essentially by making the negative electrode of the battery half of lead and half of carbon. They can quickly absorb and release large bursts of energy over millions of cycles without significant degradation. In tests, a Honda Insight hybrid powered by the UltraBattery system has surpassed 100,000 miles on a UK test track with the batteries reported to be still in "perfect condition" at the end of the test. Construction work is beginning on the world's first zero-carbon city, which will house 50,000 people in a car-free environment. Masdar City in Abu Dhabi will run entirely on renewable energy including solar power. It is scheduled to be completed in 2013. Residents will be able to move around the six-square-kilometre city using a light railway line and a series of automated transport pods. The UK government has published a White Paper on the role of nuclear power in reducing UK carbon emissions and assuring energy security through a diversity of energy sources. The paper includes issues of safety, disposal and how to meet the shortage of required engineering and science skills and knowledge. The European Commission has adopted an ambitious package of proposals to help provide energy security and meet the EU's "20 / 20 / 20 by 2020" goals, namely by 2020 to reduce greenhouse gas emissions by 20 percent compared to 1990 levels, to boost energy efficiency by 20 percent, and to ensure renewables account for 20 percent of all energy consumption. The package includes an updated emissions trading system; specific, binding national targets for cutting greenhouse gas emissions; a new approach to setting renewable targets using a country-by-country approach; promoting carbon capture and storage technologies; and new state aid rules for environmental protection measures. The plan still proposes that at least 10 percent of transport fuels should be biofuels by 2020, despite the strong criticism of biofuels by environmentalists. The Royal Society has published a report on biofuels which looks at issues relating to feedstock, conversion and biorefining, end use and distributions, and how to evaluate the impact of biofuels. The report warns that, without the right policies to drive their development, biofuels will not bring about significant cuts in greenhouse gas emissions and could be environmentally damaging. It questions the EU's Biofuels Directive for focusing on supply-based targets, namely that 5 percent of transport fuel supply must come from biofuels by 2010 and 10 percent by 2020. It argues that a better approach would be to set greenhouse gas reduction targets that can stimulate wide-ranging innovations. The report also says that there are social, economic and environmental uncertainties associated with biofuels and that the precise greenhouse gas abatement potential of biofuels must be underpinned better by robust science. Many new studies have cast grave doubt on the viability of biofuels, particularly on biofuels produced from sugar and starches derived from food crops or from feedstock grown with land and water needed to produce food. The hope is that second generation biofuels made from cellulose and lignin may prove more sustainable. Encouragingly, the US Agricultural Research Service has now reported that yields from farm-scale plantings of the switchgrass Panicum virgatum - a tall prairie grass native to North America - are a lot higher than expected. The results suggest that producing ethanol from the cellulose in these crops will be about twice as energy-efficient as previously estimated. The researchers measured the energy needed to grow the crops, including that used to make fertilisers and the diesel consumed by farmers' vehicles. From the biomass of grasses harvested, they calculated that ethanol derived from them should yield 5.4 times as much energy as all these inputs combined. The switchgrass can be grown on marginal land not suitable for food production. Butanol has advantages over ethanol as a biofuel. It packs more energy per gallon and it is less corrosive and does not mix with water, so it can be shipped easily in existing petroleum pipelines. Many teams are trying to genetically engineer bacteria to make butanol, but the process needs to be energy efficient and cost effective on an industrial scale. A significant step by scientists at UCLA has been to genetically engineer E.coli to turn sugar into isobutanol, a high octane form of butanol. E.coli is a relatively robust and unfastidious bacterium that should be easy to handle industrially and the biochemical pathway can also be applied to make other microbes produce butanol. Sugar is not a good feedstock because it is derived from food crops, but other researchers are showing that cocktails of microbes can produce butanol from lignocellulosic materials such as woody stems, agricultural waste and other waste materials. French researchers have created a device that converts the impact energy of falling raindrops directly into electricity that might be used to power remote sensors. It uses a 10 cm strip of a piezoelectric plastic, polyvinylidene fluoride (PVDF), 25 microns thick. This vibrates when struck by raindrops and some of the vibrational energy is converted into electricity. The researchers found that drizzle produces mm-wide droplets with an impact energy of around 2 microJoules, whilst a downpour produces 5 mm-wide drops with an impact energy of 1 milliJoule. In lab tests the device generated CW outputs ranging from 1 microWatt to 12 mW, depending on the droplet size. Dye-sensitized solar cells, based on dye molecules adsorbed onto titanium dioxide electrodes, are promising for solar power. They are cheap, easy to make, and can give efficiencies of over 11 percent. The snag has been that the high-efficiency cells use volatile organic solvents as electrolytes and must be kept cool - a big problem outside in sunshine. Now researchers in Lausanne have developed a solvent-free dye-sensitized solar cell based on a binary ionic liquid electrolyte. Under simulated sunlight conditions, this has given a light-conversion efficiency of 7.6 percent. |
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| [M] Materials, structures and surfaces | |
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In general, mechanical deformation tends to increase the number of dislocations in a material. But the reverse can happen for nano- and micron-scale structures, because being so small they have a much higher ratio of surface area to volume. By using a diamond punch to compress nanoscale pillars of nickel, researchers have observed that the compression drives the dislocations out through the surface of the material before they have time to interact and multiply, a process they have called mechanical annealing. With few active dislocations, the material cannot then deform until the compression is strong enough to create new dislocations. The researchers believe this "dislocation starvation" explains why structures made of metal become stronger as their dimensions approach the micron scale. This strengthening was first discovered in the 1950s in metal whiskers. Particles carrying isolated north or south magnetic poles, otherwise known as magnetic monopoles, are often conjured in theory but have never been seen in experiments. Now, physicists in the US, UK and Germany predict such monopoles should exist in magnetic materials called ?spin ices?. These are materials containing an array of magnetic spins arranged on a lattice of tetrahedra. Unlike free electrical charges, magnetic monopoles have limited movement. They could produce both steady and alternating magnetic currents and might also be useful for high-density magnetic memories. Simulations suggest that it is feasible to make negative refractive index metamaterials that work for sound waves. An acoustic superlens based on such acoustic metamaterials could produce ultra-sharp medical scans and more detailed seismic maps. The materials could also block sound waves and damp noise or vibrations. This could be on many scales - from tiny electronic or mechanical components up to large buildings that might be protected from earthquake shear waves using columns with the metamaterial inside. Hiding submarines from sonar is another possible application. High-performance piezoelectric materials, such as those in probes for medical ultrasound, are specially grown crystals of mixed composition known as ?solid solutions.? These are expensive to manufacture and difficult to study. Now US researchers report that pure crystals of lead titanate at high pressure show the same transitions seen in more complex materials; indeed, calculations suggest they could have the largest piezoelectric response of any material known. This raises the prospect of producing cheap piezoelectrics with extremely high performance. Researchers at the University of Minnesota have grown functioning hearts in the laboratory. They did this by taking a dead rat or pig heart, removing the cells to leave only the intracellular matrix as a scaffold on which to grow the new heart, and then reseeding this scaffold with a mixture of live progenitor cells that came from newborn rat hearts. Four days after seeding, contractions were observed; eight days later the hearts were pumping. The eventual goal is to be able to grow transplantable human hearts using patients? own stem cells. Engineers at the University of Massachusetts Amherst have found that a strong electric field can stabilize the surface of metals and other solids that conduct electricity, inhibiting the formation of cracks caused by stress. The researchers say that this innovation could improve the function and reliability of a wide variety of machines including aircraft, electronic devices and medical implants. The electric field causes atoms on the surface of the material to migrate, inhibiting the formation of cracks and healing cracks that have already started. A water-repellent coating developed at Dstl Porton Down is being used to produce waterproof cell phones, MP3 players and other portable electronics. The coating was originally developed for treating soldiers' uniforms so they would repel toxic vapours and liquids in a chemical or biological attack. It is transparent and is plasma bonded to the surface, repelling water and preventing it from seeping into the device. Water damage is one of the top reasons for insurance claims on mobile phones. Swiss researchers have developed miniature airbags that inflate explosively. The concept is that an array could spring into action like explosive bubble wrap to cushion impacts on the ground, particularly for landing small sensors on other planets. The balloons might also be used to flip sensors over if they are upside-down or to unfurl solar panels. Similar micro-balloons have also been developed at the University of Twente for pumping fluid. The pump cycle works by rapidly vaporising droplets of ethanol to inflate a micro-balloon in 1 to 2 microseconds. The vapour then rapidly condenses back to liquid again ready for the next pump cycle. The researchers say that the balloon delivers more than a thousand times the power of other similar-sized micro-devices. |
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| [E] Environment, transport and marine | |
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The Brazilian government has announced a huge rise in the rate of Amazon deforestation, months after celebrating its success in achieving a reduction. In the last five months of 2007, 3235 sq km of forest were lost. Officials say rising commodity prices are encouraging farmers to clear more land to plant crops such as soya. Researchers from the Fraunhofer Institute for Solar Energy Systems (ISE) have successfully tested small stand-alone solar-powered water treatment plants. The plant consists of six square metres of thermal solar collectors, a small photovoltaic module to power a pump, and the desalination module, which uses membrane distillation. The salty water is heated up and guided along a microporous, water repellent membrane. Cold drinking water flows through the other side of the membrane, and the temperature difference causes some salt water to evaporate and pass through the membrane leaving the salt behind. The advantage of this approach compared with methods such as reverse osmosis or solar water distillation is that it is robust and uncomplicated. In addition, the system recovers the heat after the distillation process, making it more energy-efficient. The Arctic is warming about twice as fast as the rest of the globe, but the reason for this remains a mystery. Melting sea ice means that less sunlight is reflected. But this does not seem to be a major factor in the warming so far, according to researchers at the University of Stockholm. From satellite data taken in the 1980s and 1990s, they found that most of the warming was happening far above the surface; at midsummer the air that had warmed the most was at an altitude of 2000 metres. Meteorological data suggests the warming may be due in large part to an increasing number of cyclones moving into the Arctic Circle, carrying warm air. Ice loss in Antarctica increased by 75 percent in the last 10 years due to a speed-up in the flow of its glaciers. The loss is now nearly as great as that observed in Greenland, according to a new, comprehensive study by NASA and university scientists. The El Ni?outhern Oscillation (ENSO) typically consists of an El Ni?hase followed by a La Ni?hase. During the El Ni?hase, eastern Pacific temperatures near the equator are warmer than normal, while during the La Ni?hase the same waters are colder than normal. These fluctuations in Pacific Ocean temperatures are accompanied with fluctuations in air pressure known as the Southern Oscillation. Modelling is increasingly revealing how ENSO affects climate and severe weather systems all over the globe, and also how the ENSO cycle is coupled to other atmosphere-ocean cycles. Although the North Atlantic has warmed overall during the past 50 years, the subpolar regions have in fact become cooler, while further south the ocean has warmed up, according to research at Liverpool University and Duke University. The study, which used five decades of ocean temperature data, indicates that the North Atlantic Oscillation (NAO) has a very big effect on temperature changes. Analysis of the data using computer models has helped to predict how wind and heat exchange with the atmosphere affects the ocean's heat content. It showed that over mid latitudes the ocean warming is due to winds directly redistributing heat, whilst the warming in the tropics and cooling at high latitudes is due to heat exchange between ocean and atmosphere, which is strongly affected by winds. The resulting local changes in heat storage are typically 10 times larger than any long term trend due to global warming. All this highlights the difficulties in measuring the underlying effects of global warming. Researchers at UCL have quantified the link between changes in sea surface temperature and increases in hurricane activity in the tropical North Atlantic, Caribbean and Gulf of Mexico ? the region that produced nearly 90 percent of the hurricanes that reached the US between 1950 and 2005. The researchers created a statistical model based on two environmental variables ? local sea surface temperature and atmospheric wind field. This replicated 75-80 percent of the variance in tropical Atlantic hurricane activity and frequency between 1965 and 2005. By removing the influence of winds from the model, the researchers assessed that local sea surface warming was responsible for about 40 percent of the increase in the hurricane activity between 1996 and 2005. They also assessed that a 0.5 degree C increase in sea surface temperature can be associated with around 40 percent increase in hurricane activity. It is not clear how far the recent higher sea temperatures are due to natural climate cycles and how far they might reflect global warming. More severe droughts and flooding could be a problem for nuclear power. Currently, the La Ni?n the eastern Pacific is producing cold wet weather in the US Northwest, frigid weather on the US Plains, and record dry conditions in the US Southeast. La Ni?vents can sometimes last several years and if this one continues into the summer, the drought in the US Southeast is likely to force a shut-down of nuclear power stations as water levels in lakes and rivers fall too low to safely cool the reactors. Satellite instruments are being used to monitor the La Ni?y measuring sea surface temperature, marine life, oceanic winds, rainfall and also the sea surface height, which falls because of the cooler ocean water associated with a La Ni?a href=http://iqnewsnet/imagineaway.asp?SID=11802 target="data"> |
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| [R] Remote sensing and sensor systems | |
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Synthetic Aperture Radar (SAR) instruments, such as the Advanced Synthetic Aperture Radar (ASAR) instrument on ESA?s Envisat, can image patterns of surface roughness that are linked to surface winds, waves and currents. However, interpreting the radar images to identify and quantify surface currents has proven very difficult. Researchers have now overcome this problem by also exploiting the Doppler shift of the radar signal from the water surface. A Scientific American article reviews current technologies for indoor positioning systems. These use radio, ultrasound or infrared signals to more precisely track locations in buildings where GPS signals are blocked. A team of European researchers has developed an innovative traffic control system that uses an array of small, inexpensive sensors to monitor the 'magnetic fingerprint' that planes' metallic bodies leave on the Earth's magnetic field. Tests at airports in Germany and Greece show the system detects all passing aircraft and in 75 percent of cases it can pinpoint the aircraft's location to within 7.5 metres - comparable to most existing systems. Its advantage is that it can see through obstacles, such as buildings and airport parking lots, and through the thickest fog or heaviest rain. Dark-field microscopy is used by biologists to improve contrast when imaging cells with a visible microscope. It achieves this by using only scattered light. Researchers have now shown that the same principle can be applied to x-ray images. For medical x-rays, the technique can reveal physical details that would normally be invisible. For example, since soft tissue and bone differ strongly in their ability to scatter x-rays, the dark-field technique could help a doctor spot small splinters of bone or cartilage after a bad fracture. The technique could also enable x-ray security screening to distinguish explosives from substances that would otherwise look identical. For example, some kinds of cheese absorb x-rays in a similar way to plastic explosive, but they scatter them differently. The US Air Force/Navy HAARP transmitter has been used at 7.4 and 9.4 MHz to make radar measurements of the lunar sub-surface topography, exploiting the ability of the low frequency radar to penetrate to varying depths below the visible surface of the Moon. The experiment has also allowed the researchers to study the interaction of the echo signal with the Earth?s ionosphere along its return path, because the ionosphere is only partially transparent at low frequencies. It may be possible to use telescopes carried by high altitude balloons to directly view planets in other solar systems. At altitudes 10 km or more above the Earth's surface, light from distant stars suffers very little distortion from atmospheric turbulence. Scientists were not sure, however, whether turbulence produced by a balloon might be a problem. Now a laser experiment carried on the Solar Bolometric Imager, a balloon-borne observatory that flies at an average altitude of 36 km, has shown that any distortions caused by the balloon are sufficiently slight that exoplanets could be imaged by a telescope with a mirror of 1 to 2 metres diameter. Astronomers have detected radio emissions coming from within 30 million kilometres of the dark object, thought to be a colossal black hole, that lies at the centre of the Milky Way. Previously, astronomers could see no closer than 100 million kilometres from the object, called Sagittarius A. The new observation zooms within three times the radius of the hole's event horizon. The radio waves were picked up in April 2007 using three separate observatories in the US states of Hawaii, Arizona and California that were linked together to form a very long baseline interferometer 4500 kilometres across. When Chile's Atacama Large Millimetre Array becomes operational in 2010, it will extend the global array of telescopes still further. That should make it possible to see detail on the same scale as the event horizon and observe how the hole is warping space-time. It is thought that the Milky Way's centre has a lot of dark matter. If this is composed of WIMPs (weakly interacting massive particles), their interaction should be producing neutrinos. Searching for these neutrinos using the Super-Kamiokande neutrino detector in Japan has so far found nothing. But a much larger neutrino detector called IceCube is due to be completed by 2011. This will use 80 strings of detectors buried within the ice at the South Pole to detect tracks of light from neutrinos interacting with the ice and producing muons. Because a million times more muons are produced in the Earth's atmosphere, IceCube looks for muons produced by upwards-going neutrinos that have passed right through the Earth, using the Earth to screen out the atmospheric muons. Unfortunately, the galactic centre lies in the constellation Sagittarius in the southern hemisphere, meaning that any WIMP-produced neutrinos will be downwards-going. It is now proposed these might be detected by putting a smaller neutrino detector inside IceCube and using IceCube to subtract the atmospheric muons. Using the Near-Infrared Multi-Object Spectrometer on the Hubble Space Telescope, astronomers at the Carnegie Institution have found first indications of highly complex organic molecules, called tholins, in the disk of red dust surrounding a young star. The star is only 8 million years old and is inferred to be in the late stages of planet formation. The presence of tholins suggests that the basic building blocks of life may be common in planetary systems. Tholins do not form naturally on present-day Earth because oxygen in the atmosphere would quickly destroy them. But they are hypothesized to have existed on the primitive Earth and may have been precursors to the biomolecules that make up living organisms. Tholins have been detected elsewhere in the solar system, such as in comets and on Saturn?s moon Titan, where they give the atmosphere a red tinge. This study is the first report of tholins outside the solar system. Astronomers using the Arecibo Observatory radio telescope have reported the detection, for the first time, of the molecules methanimine and hydrogen cyanide - building blocks of amino acids - in a galaxy some 250 million light years away. |
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| [S] Sensor devices | |
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Researchers at the Max Planck and Leibniz University have produced the world's lowest noise laser and have achieved a new world record in the control of photons by precisely placing the photons in a specific order, thereby reducing the photon noise by 90 percent. This extremely low noise "squeezed light" can be used in quantum key distribution and can also dramatically increase the sensitivity of gravitational wave detectors. This could extend the reach of gravitational wave detectors by a factor of three, making it feasible to observe black hole collisions at the edge of the universe. Lawrence Livermore and Sandia have jointly developed a compact detector that can measure the flux of antineutrinos from a nuclear reactor. In conjunction with knowledge of the input fuel load and core design, the measurement provides a direct measure of the reactor?s power and isotopic content, enabling international non-proliferation inspectors to monitor the reactor's operation and plutonium inventory. The detector operates unattended for long periods without significant maintenance, is self-calibrating, near impossible to spoof, and does not affect plant operations in any way. Scientists have found a way to quickly identify which DNA sequences are ideal for detecting a particular odour. By making a microarray of say 20,000 sensors, it should be possible to detect specific odours of interest from the individual sensors that respond. A DNA microarray (gene chip) is a collection of microscopic DNA spots, commonly representing single genes, attached to a solid surface, such as glass, plastic or a silicon chip. Thousands of these DNA segments, known as probes, are placed in known locations on the array, and can be used to examine thousands of genes at the same time. However, because the probes are pinned to the solid surface, it is hard for the target molecules to reach the right probes. Researchers at Arizona State have now shown that they can instead build DNA microarray probes from self-assembling DNA tiles. On the surface of each tile is a dangling single stranded piece of DNA that can bind to the RNA target of interest. The researchers say the technology can provide extremely high sensitivity and because the probe tiles are a water-soluble reagent, the sample volume can potentially be shrunk down to the volume of a single cell. This could enable gene expression to be measured at the single cell level. The optofluidic interactions that occur when a liquid flows through a tiny channel next to light in an optical waveguide could lead to new ?lab-on-a-chip? sensors, according to computer simulations by researchers at Cornell. Light in the waveguide creates a short range evanescent electric field and this field can trap tiny particles in the fluid. In this way, objects such as bacteria, DNA or quantum dots could be temporarily held by the light so that they could be analysed. The researchers have devised numerical criteria that describe the conditions under which it is possible to transport and trap an object optofluidically. They have also experimentally demonstrated optofluidic trapping and transport of polystyrene beads using polymer waveguides. Optofluidic sensors could be used in a wide range of areas including medicine and security. |
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| [O] Optoelectronics, optics and lasers | |
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A material with a reflectivity of only 0.045 percent, three times darker than the blackest material ever made previously, has been produced by physicists at the Rensselaer Polytechnic. It consists of an array of vertically aligned, low-density carbon nanotubes whose surface roughness was tuned to minimise its optical reflectance. The researchers say that periodic nanotube structures are ideal for creating superdark materials because their light absorption can be tailored by controlling the dimensions and periodicities of nanotubes in the structure. Superdark materials are valuable in astronomy and photography, and the material might also be used in solar cells to give very high absorption of the solar radiation. Using computer modelling and laser measurements, researchers are trying to establish the intrinsic vibration modes of capsids - the protein shells of virus particles that package the genetic material. The hope is that it might prove possible to kill pathogenic viruses mechanically by rupturing them with sound or light tuned to a suitable vibration mode. It may be possible to render human tissue transparent by using optical phase conjugation, according to researchers at Caltech, ?F Lausanne and MIT. They used a holographic crystal to record the scattered light pattern emerging from a 0.46-mm-thick piece of chicken breast. Then they holographically played the pattern back through the tissue section to recover the original light beam. If this technique can be extended to thicker tissue, it could be used for photodynamic therapy in which a beam of light is highly focused on a tumour to activate light-sensitive cell-killing compounds. Currently this therapy works best in treating skin cancers, but by rendering the tissue transparent it could be used on deeper tumours. In experiments that could change how spectroscopy is done, physicists at NIST-Boulder have used an optical frequency comb to measure the full spectrum of a gas with a precision as fine as 1 Hz. This compares with tens of MHz precision typical with other spectroscopic techniques. The measurement is quick and involves no moving mechanical parts. Recent advances enable nanoresonators to be made small enough to reach the quantum regime, where the average thermal energy kT is less than the ground state energy of the resonator (equal to Planck's constant times the frequency of the resonator). A 1 GHz nanoresonator, for example, reaches the quantum regime when cooled to 48 milliKelvin. Studying such resonators has been hard because they are so tiny. Now, physicists in Italy and Australia have found a way to entangle a quantum nanomechanical resonator with microwaves by coupling the resonator to the microwaves via a capacitor. Apart from studying quantum nanomechanics, the entanglement could be used in quantum information processing and to detect ultra light masses and extremely weak forces, such as forces due to quantum effects or gravitational forces at micron distance scales (to look for departures from the inverse square law that might reveal the existence of extra dimensions predicted by string theory). The researchers say their device could also work as a nonlinear element in superconducting microwave circuits, as a substitute for Josephson junctions. Light in a conventional optical fibre is guided through the bulk of the glass or plastic of the fibre. But, in a hollow-core fibre it is instead guided down a hollow air core in the centre of the fibre, thereby avoiding dispersion and optical damage effects that occur in glass or plastic. Unfortunately, hollow-core fibres are difficult to fabricate and only work for a limited range of wavelengths. Now, scientists at Bath University have discovered a way of speeding up their production so that it takes only a day rather than a week. The resulting fibres are also superior in virtually every respect to current hollow-core fibre. |
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| [I] IT, communications, networking and secure systems | |
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Homes and businesses across Europe may soon receive ultra high-speed broadband over cheap and easy-to-install plastic optical fibres. A consortium developing the technology hopes to provide 80 percent of European homes with broadband up to 50 times faster than today's ADSL within 15 years. Twenty European partners from industry and academia are jointly developing a new global standard for gigabit home networks combining gigabit wireless and free-space optical links with power line communications. Services that might use such bandwidth include new generation entertainment services such as telepresence, 3D gaming, enhanced interactivity, virtual reality, high-definition video as well as e-health applications and services for the exchange of user-generated business or multimedia content. The 60-GHz band is an unlicensed wireless band offering large bandwidth and worldwide interoperability. It is attractive for wireless local networks where the short range of 60 GHz is an advantage in avoiding mutual interference. Applications include personal area networks, wireless home networks and HDTV, wireless laptop docking stations, wireless Gigabit Ethernet and wireless board level communications within computers. Transceivers at 60 GHz can be built in silicon, and there is also interest in using metal-insulator electronics. Metal-insulator devices are cheap, compatible with CMOS processing, and have achieved extremely high frequencies of up to 3.8 THz. They have a four-layer stack of metal-insulator-insulator-metal. The two metals and insulators are so tailored that they form a quantum well between the insulators, which allows only electrons above a threshold energy to tunnel through. When the applied voltage exceeds this threshold, ballistic quantum tunnelling occurs in femtoseconds, giving the extremely high speed. According to Scientific American, the US Navy is hoping to use expendable acoustic buoys to relay messages from communications satellites to and from submerged submarines located up to 175 miles away, depending on acoustic propagation conditions. Boeing's new 787 Dreamliner passenger jet may have a security vulnerability in its onboard computer networks that could allow a passenger to hack into the plane's control systems, according to the US FAA. The concern is that the computer network in the Dreamliner's passenger compartment, which is designed to give passengers in-flight internet access, is physically connected to the plane's control, navigation and communication systems. A more secure design would physically separate the two computer networks. Boeing has said that it has designed a solution and will be testing it shortly. |
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| [K] Knowledge, information and technology management | |
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Yahoo Go is a suite of downloadable tools that allow people to carry out every day internet tasks on a mobile phone. It enables them to search the net, send emails, upload photos, download maps and receive news updates. So far, users have been limited to browsing and using Yahoo content. Now Yahoo has announced that the latest edition, Go 3.0, will allow third party developers to create widgets that will suck content from other areas of the net. The Go 3.0 prototype allows users to import contacts from social networking sites such as MySpace, it automatically prioritises messages from across all networks, and it allows the user to drag a message on to a map tool to see quickly the location of places linked in the body of the message. Intel is predicting that over the next five years, mobile devices will deliver a more personal internet by using chips with the power of today's desktop PCs. Devices will augment reality by pulling data from the net in real time in a way that is proactive, predictive and context-aware, and will be capable of delivering the full internet, with no compromises. The first generation of mobile internet devices is likely to be pocket sized, but Intel expects the size will shrink by a factor of four within two years. According to BBC News, five information and communications technologies that could become big in 2008 are: mobile web, ultra-mobile PCs, Internet TV, Wimax and Mobile VoIP. A new computer-based text-searching tool automatically and quickly compares multiple documents in a database for similarities, providing a more efficient method to carry out literature searches. It is especially aimed at investigators who wish to analyze an unpublished abstract or project idea in order to find previous publications on the topic or identify possible collaborators working in the same field. It also offers a way to detect plagiarism or multiple publication of the same material. An analysis of more than seven million Medline abstracts turned up nearly 70,000 highly similar papers. More than a billion people have become connected to the World Wide Web, creating seemingly limitless opportunities for communication and collaboration. People are using the Internet and Web applications to communicate in previously impossible ways. Social networking has emerged rapidly as a cultural paradigm shift that is turning the internet into a hub of socialization, a social utility. An article in IEEE Computer reviews some of the major drivers: MySpace, Facebook, Wikipedia, YouTube and Google's open source framework aimed at standardising and integrating the social network movement into a social platform. The ties that people make and break through social sites are helping academics understand relationships. Facebook is particularly useful to sociologists because of the way members accurately record relationships. Friends can add applications to compare tastes in everything from films to music to books. This can, for example, help researchers establish how far people tend to form relationships with others who are similar to themselves. The UK National Health Service (NHS) is the largest organisation in Europe and has been going through a decade of major change in its organisation and management. A study by McKinsey and LSE has examined the effectiveness of management practices within NHS hospitals. It has found that, overall, NHS hospitals still rank substantially lower than UK industrial companies in average management-practice scores. However, the direct involvement of doctors in the management of a hospital helps to improve its performance. In particular, the involvement of doctors in target setting, talent management, and business leadership correlate with lower rates of infection and readmission, more satisfied patients, more productive staffs, and higher financial margins. Hospitals are also better managed if they have a higher proportion of clinically trained managers. Finding and retaining talented employees is at least as challenging today as it was ten years ago, according to a McKinsey report. Demographic trends, globalization, and the growth of knowledge work have intensified the external pressures on companies. Many companies are also compounding the problem by failing to make talent management a strategic priority. The report identifies seven main obstacles that undermine talent-management. It recommends that executives need to act on their rhetoric about the importance of employees in creating competitive advantage, they must embed a robust talent strategy in the overall business strategy that focuses on all workforce segments and not just on the top performers. The report also warns that the scope to fill the talent gap with graduates from developing countries is limited because of poor English skills, dubious educational qualifications, and cultural differences. Other challenges are finding enough people willing to work internationally and coping with the different expectations of so-called generation Y graduates - those born after 1980. |
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| [C] Computing, supercomputing, modelling and simulation | |
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Researchers in Germany, China and Austria have created an experiment in which a quantum bit of information is transported across a distance of seven metres and briefly stored in memory. This is the first time that both quantum memory and quantum teleportation have been demonstrated in a single experiment, albeit that the quantum memory duration is very short and the probability that the photon will be teleported is low. Scientists at UCL have used a prototype of a 'Virtual Physiological Human' (VPH) to simulate the efficacy of an HIV drug in blocking a key protein used by the virus. The VPH concept involves linking networks of computers from around the world to simulate the inner workings of the human body. With it, scientists can study the effects of a drug and see what is happening at the organ, tissue, cell and molecular levels. Currently, the VPH is still in the early stages of development, but researchers hope that eventually doctors will be able to use it to develop personalised treatments for their patients. Researchers at Caltech have shown it is possible to program the interactions between DNA molecules to implement different dynamic functions using the same components. Their system is based on hairpin-shaped strands of DNA each about 10 nm long with three specific binding sites. The hairpins can snap together in specific ways and behave like interconnected logic gates. When a hairpin is closed, for example, two out of its three binding sites are unavailable. But, if a suitable strand of DNA docks with it, the hairpin springs open. A reaction between two DNA strands can also free up the exposed site on an attached hairpin, causing it to close once more. The researchers have developed a graphical way to represent the state of these molecular building blocks and the step-by-step interactions between them. These "reaction graphs" allow them to map out the assembly and disassembly steps needed to produce a desired sequence of reactions. As an example, they used their system to construct a piece of DNA that walks along another strip of DNA. |
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| [W] Whole life engineering, manufacture and testing | |
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Tools may soon allow users to build virtual worlds simply by using a markup language, style sheets, modules, and a scripting language just as for any other type of website. Programming has come a long way from the era of writing instructions in machine code. But it still involves the need to write down a program as a symbolic, textual, or graphical artefact, to specify requirements (the what) separately from the program (the how), to test one against the other, and to structure behaviour according to the system's structure. An article in IEEE Computer paints a vision of how, as future systems become more human-like and reactive, it may become possible to program them instead by a walkthrough process of guiding, teaching, coaching, and constraining. Similar to the way a child learns, the process would be playfully interactive, carried out directly and visually with the system's external or internal interface, and combining the what and the how. This play-in process would be a sort of formal language that the computer knows how to record, execute and consistently verify. Recent progress in scenario-based programming provides some evidence that this approach is feasible. Chemical engineers at Princeton have developed a method for shooting stable jets of electrically charged liquids from a wide nozzle. The technique, which uses a half-millimetre diameter nozzle to produce lines just 100 nm wide, offers at least 10 times better resolution than ink-jet printing and far more speed and ease than conventional nanotechnology. The ability to print such fine lines quickly over wide areas could lead to larger, less expensive and more versatile electronic displays as well new medical devices, sensors and other technologies. |
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| [X] Systems, complexity and risk | |
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A report published by the UK government compares productivity performance between France, Germany, UK and US. It does this sector by sector in finer detail than has been attempted before. At detailed sector level, there are some remarkably large differences in productivity between countries, some of which are hard to understand. In general, the differences mainly relate to capital-intensity, which increases the added-value per hour worked. In 2002, the German capital-labour ratio was roughly 75 percent above the UK while the US was 37 percent higher and France 33 percent higher. Since then differences in Europe have narrowed but the US advantage has increased. The UK weakness is partially offset by the fact that it makes more efficient use of its capital equipment and also of its skilled labour. In labour quality, the aggregate difference between countries is 4 percent or less, and closing. But at sector level there are large differences in labour quality between countries. A UK government report looks at what government can do to improve national productivity and competitiveness. It looks at ways of improving corporate governance, leadership and management skills, user knowledge and user-driven innovation, and the productivity of small and medium sized enterprises (SMEs employ 59 percent of those working in the UK private sector). It also examines regional disparities and the economics of growth in cities, regions and pan-regional working. The growing complexity of world markets makes the global financial system increasingly vulnerable to being rocked by modest aberrations, according to MIT. In August 2007, when a large equity fund decided to unwind its portfolio for reasons possibly linked to subprime mortgage issues, this triggered a small crash in which many similar funds lost money. Now, on a wider scale, the unwinding by Societe General of the rogue trades discovered on 19 January 2008 may have triggered the global sell-off shortly afterwards. The greater and greater complexity of financial systems means that such systemic shocks are increasingly likely and can be quickly amplified. To counter this, a way is needed to provide greater transparency about what is happening. The first global accounting taking into account environmental cost shows that rich nations have inflicted ecological damage on poor countries that is estimated at around $2.5 trillion over the past 4 decades. This is more than the $1.8 trillion total that poor nations have borrowed from rich countries. It took at least 30 million years for ecosystems to fully recover from the Permian mass extinction that occurred 250 million years ago, according to a new study from the University of Bristol. The Permian extinction wiped out over 90 percent of all species. The present loss of biodiversity is nowhere near this level, but the findings show that recovering from a major ecological crisis takes much longer than previously supposed. |
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| [V] Virtuality and human-machine interface | |
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Although the sales of video games still continue to grow strongly, the cost of developing new games has grown much faster. So also has the sophistication and skills needed both in the programming and in the artwork design, which now exceeds programming in cost. Games consoles are now so powerful that most have to be sold below their manufacturing costs with the loss being recovered through console fees on each game. Reducing costs, for example through automating some content creation such as animation, and through direct selling to consumers, is one way to improve profitability. Finding new revenue streams, notably through massively multiplayer online role-playing games, is another. Additional growth is coming through developing specialized interface peripherals that let the player interact with the game in engaging new ways, such as through dancing or other body movement. Selling virtual goods and small chunks of additional game content are other revenue-enhancing trends. The way people interact with computers is going to dramatically change in the next five years, according to Bill Gates. He predicts that the keyboard and mouse will gradually give way to more intuitive and natural technologies, particularly based on touch, vision and speech. A consortium of five European research institutes has developed a tactile haptic technology that allows people to touch, stretch and pull virtual fabrics that feel like the real thing. It uses two models: one tracks the overall properties of the material and the second is fine-grained and maps the actual sensation on skin. This is then combined with a detailed visual representation of the textile. There is very wide potential for shopping, design and human-machine interaction. Holograms were invented by Gabor in 1947 and have become very widely used for authentication tags. Now they are also starting to provide cheap and powerful diagnostic tools. These so-called smart holograms are recorded in a polymer matrix whose optical properties change in response to desired physical, chemical or biological stimuli. If the matrix is exposed to the specific stimulus, the hologram changes. This can be engineered to happen in a way that gives a visual output that is easy to interpret. A first application has been an easy-to-use water contamination detector for aviation fuel. The hologram instantly generates an easily discernible red cross if the water content of the fuel is above the safe limit. The ability to detect the presence of ions, metabolites and enzyme activity also makes holographic sensors attractive for monitoring disease-specific markers in blood and for other medical diagnostics. The direct visual output can make it easier for such tests to be done on the ground by lay staff rather than involving the cost and delay of sending samples away for lab testing. Researchers at Children?s Hospital Boston have devised a way to get tiny superparamagnetic beads, 30 nm in diameter, to bind to receptor molecules on a cell surface. When exposed to a magnetic field, the beads become magnets and pull together, dragging the cell?s receptors into large clusters. This clustering mimics what happens when drugs or other molecules bind to the receptors. It activates them, triggering a cascade of biochemical signals that influence different cell functions. This is the first time that magnetism has been used to harness specific cellular signalling systems normally used by hormones or other natural molecules. The researchers say this allows the behaviour of living cells to be controlled through magnetic forces rather than chemicals or hormones. It may also provide a way to interface neurons and other cells magnetically to computers and other machines. |
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| [B] Brain research and human science | |
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While attempting to treat a morbidly obese man through deep brain stimulation (DBS), doctors in Canada discovered that electrical stimulation of the hypothalamus caused the patient to experience vivid memories from his distant past. If the findings are repeated on other patients, it is possible that DBS might help people with memory loss. Researchers at MIT report that they have created a way to see, for the first time, the effect of blocking and unblocking a single neural circuit in a living animal. They used their new technique to study how bypassing one of the two main information-carrying routes in the hippocampus, called the tri-synaptic pathway (TSP), affected learning and memory in mice. The results indicated this pathway plays a crucial role in quickly forming memories when encountering new events and episodes in day-to-day life. The body's central circadian clock is located in the brain's hypothalamus and synchronises with the 24-hour day-night cycle via light receptors in the eye. Each cell of the body also has an internal "clock" that involves certain genes turning on and off in sequence. The central clock synchronises these cellular clocks by causing a gene called Bmal1 to be more active in cells during the daytime. Swiss and German researchers have now shown that this cellular clock can be monitored using skin cells. They used a virus to equip skin cells taken from 11 early-rising people dubbed "larks" and 17 late-rising "owls" with a firefly gene that would produce a visible glow whenever Bmal1 was active. This revealed a 24-hour rhythm in the cells. In most cases its timing corresponded to whether the skin cells came from owls or larks. There were discrepancies, however, most notably in three individuals with seasonal affective disorder. This suggested that skin biopsies might be useful for diagnosing sleep and circadian disorders. Researchers at the University of Pennsylvania have shown both in round worms and various mammals that sleep is associated with synaptic changes, suggesting that sleep is a downtime in which change to neural circuits can be made offline. New research at the University of Wisconsin supports the hypothesis that people sleep so that their synapses can downsize and prepare for a new day and the next round of learning and synaptic strengthening. The human brain expends up to 80 percent of its energy on synaptic activity, constantly adding and strengthening connections in response to all kinds of stimulation. The researchers found in experiments on rodents that, for the same levels of stimulation, synaptic responses were strong following a long period of waking and weak after sleep. Research in Israel and Canada has shown that a short nap during the daytime improves the consolidation of long term memory and protects against memories being interfered with by new learning. A study at Ben Gurion University has shown mathematically that any system is more efficient when it focuses on one task at a time, rather than trying to multitask. This model may lead to a more precise biological explanation for why sleep and other biological cycles evolved. With a sleep-wake cycle, the brain collects information when it is available - for most animals this is during daylight - and processes it offline during sleep at times when there is much less inform | |||
