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Top Stories in Science
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April 2007 Issue |
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| [D] Defence and security |  |
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Security Council debates climate change The UN Security Council has held its first ever debate on climate change. The debate was initiated by Britain during its presidency of the Council. Some nations argued that climate change is not an appropriate issue for the Security Council. The UK maintained that the Security Council is the forum to discuss issues that threaten the peace and security of the international community. These threats now include the risk of conflict over water resources, major changes to the world's physical landmass during the 21st century resulting in border and maritime disputes, the possible submergence of entire small island states, dramatically receding coastlines, and the likelihood that 200 million people could be displaced by the middle of the century. The UK also argued that there could be conflicts over scarce energy resources, security of energy supply and the role energy resources play once conflict has broken out. The UN Secretary General Ban Ki-moon supported the debate saying that there are some "alarming scenarios" that could weaken the power of states to resolve conflicts. [D][E][P]
Precipitous climate change Sudden climate change is far more frequent than previously thought, according to researchers at University of Wisconsin-Madison researchers, who have identified 30 regions worldwide that endured precipitous climatic changes during the 20th century. The Sahel drought that struck West Africa in the late 1960s and lasted nearly two decades, killed more than one million people and affected 50 million more. [D][E][P][X]
Carbon governance Britain could become the first country to set legally binding carbon reduction targets under new government plans. The draft Climate Change Bill calls for an independent panel to set ministers a "carbon budget" every five years, in a bid to cut emissions by 60 percent by 2050. If future governments miss the targets they could be taken to court. [D][E][P]
Energy security The European Union has agreed policies to tackle climate change and to protect its energy supplies. Norway aims to do even better and to reduce its greenhouse gas emissions by 30 percent by 2020 and to be a zero-emission state by 2050. [D][E][P]
Emergency response A RAND expert report has recommended actions that local communities should take to be better prepared to deal with bioterrorist attacks, pandemic flu outbreak and other large-scale public health emergencies. The report calls for communities to have a coordinated rapid-response capability with well-defined roles and responsibilities for officials and the public, a clear command structure, strong public communications, the ability to provide emergency health care to large numbers of people, and the ability to monitor the spread of a public health emergency. Communities also need to develop and maintain adequate numbers of operations-ready public health workers and volunteers, and to engage in a continuous process of testing, improvement and maintenance of systems for tracking and reporting information on readiness to decision-makers and the public. [D][H][I][K][R][X]
Coping with nuclear casualties Researchers at Duke University have developed a blood test that can determine with 90 percent accuracy whether a person has been exposed to dangerous levels of radiation, and can do this fast enough to enable hospitals to give protective treatment. The researchers say the test could help hospitals cope with a massive influx of people worried about radiation exposure in the wake of a nuclear accident or "dirty bomb" explosion. The test analyses the pattern of activity in 25 genes linked to radiation exposure. [D][H]
Drug-resistant influenza Influenza is classified into three broad types - A, B and C. Type A, which includes bird flu, causes the most serious epidemics; type B is less severe but is still capable of producing an epidemic; type C is the least virulent and usually causes only mild respiratory infections similar to the common cold. It is known that some Type A strains are now developing resistance to the drug Tamiflu, which governments are stockpiling as the best weapon available to check a flu pandemic. Now Japanese researchers have reported evidence that Type B flu is also becoming resistant both to Tamiflu and to Relenza, the other most important anti-flu drug. [D][H] |
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| [A] Aeronautics and space | |
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Artificial muscle blimp Swiss researchers have developed a 6-metre-long blimp steered by artificial muscles - plastics that stretch when a high electrical voltage is applied.. This they hope is a step to producing blimps that are also propelled by artificial muscle, wiggling their tail like a trout. The researchers say that these could be used for wildlife or crowd observations in place of noisy helicopters. They could also be "parked" high in the stratosphere as platforms for surveillance and wireless communications. [A][D][I][M][P][R][U]
Aircraft swarm control Fighter pilots will one day be able to control entire squadrons of uncrewed combat aircraft as well as their own plane, following successful flight demonstrations of a multi-aircraft remote control system developed by QinetiQ. Using the system, the pilot of a Tornado fighter assumed remote control of a BAC 1-11 airliner carrying members of the press, and was also in control of three simulated Unmanned Combat Air Vehicles (UCAVs). In addition to cutting the number of pilots risked in military operations, the remote control system could one day also be used to auto-land hijacked planes or allow lone pilots to orchestrate complex search and rescue operations. [A][I][R][U]
National UFO website France has become the first country to open its files on UFOs. The national space agency has unveiled a website documenting more than 1600 sightings since 1954. Of these, nearly a quarter are classified as "type D", meaning that despite good or very good data and credible witnesses, the observations cannot be explained. [A]
Hinode mission Hinode has obtained never-before-seen images showing that the Sun's magnetic field is much more turbulent and dynamic than previously known. Its three primary instruments, the Solar Optical Telescope, the X-ray Telescope and the Extreme Ultraviolet Imaging Spectrometer, are observing the different layers of the Sun. This is revealing how changes in the structure of the magnetic field and the release of magnetic energy in the low atmosphere spread outward through the corona and into interplanetary space. Where astronomers expected to see a calm region called the chromosphere, the Hinode images have revealed a seething mass of swaying spikes. Another surprise sighting is that of giant magnetic field loops crashing down onto the Sun's surface. [A][R]
Loss of Mars Global Surveyor The loss of the Mars Global Surveyor spacecraft in November 2006 was the result of a series of events linked to a computer error made five months earlier, according to the preliminary report of the NASA board of enquiry. The spacecraft, launched in 1996, operated longer at Mars than any other spacecraft in history, and for more than four times as long as the prime mission originally planned. It finally succumbed to battery failure caused by a complex sequence of events involving the onboard computer memory and ground commands. The team controlling the spacecraft had followed the existing procedures, but these proved insufficient to catch the combination of errors that occurred. [A][W][X]
Astronomy at lunar base Astronomers are looking at how to capitalise on NASA's planned return to the Moon. Proposals have included a telescope that would record light from the deepest reaches of the cosmos using a liquid mirror bigger than a football field. The device would be housed inside a crater at the Moon's south pole so that it could stare at a constant direction despite the Moon's rotation. Another suggestion is to deploy an array of radio telescopes on the Moon's far side, shielded from Earth's radio signals. The array would search for radio emissions from neutral hydrogen that filled the universe from about 400,000 years after the Big Bang until the birth of stars. The stars quenched this early radio-wave activity, but because stars across the cosmos did not all turn on at once, different parts of the universe became radio quiet at different times. Tuned to low frequencies, the radio telescopes might be able to discern this variation and hence trace the star birth and the early large-scale structure of the universe. [A][F][R]
Dealing with lunar dust Among the challenges in returning to the Moon is how to handle lunar dust. About one percent by weight of lunar soil comprises particles less than one micron in size, which would stick in astronauts' lungs and could produce the equivalent of silicosis. A significant fraction is less than 100 nm in size and might be "levitated" electrostatically above the surface, affecting astronomy on the Moon as well as astronauts' health. Nanograins of iron could pass straight through the lungs into the bloodstream where the iron could "de-energise" the haemoglobin, producing the equivalent to carbon monoxide poisoning. One possibility is to extract the particles magnetically. Another is to melt the dust using microwaves since these couple very strongly to the iron nanoparticles. A way must be found to safely suck up lunar soil to extract oxygen and hydrogen from it and perhaps to use it for building materials. [A][H][N][P][R]
Surviving space radiation The bacterium Deinococcus radiodurans can survive doses of ionising radiation thousands of times stronger than would kill a human. Researchers have found that it survives because it has much better protection of cellular repair proteins. Even though radiation breaks up the cell's DNA, this is not a problem because its repair proteins can stitch the DNA together again accurately. The question is whether it may be possible to copy this in humans and so increase radiation resistance for long duration space travel. [A][D][G][H][P]
Simulated Mars mission A joint project between Russia and ESA will simulate a roundtrip to Mars to explore how the isolation and stresses may affect crew members on an actual mission. In late 2008 or early 2009, six people will enter a mock spacecraft in Russia consisting of a series of connected metal tanks. The 200-square-metre 'spacecraft' will include a medical area, a research area, a crew compartment and a kitchen. The day-to-day lives of crew members will be similar to that on the International Space Station, except for the presence of gravity. The simulation including a 30 day "Mars landing" will take 530 days, about half that of a real mission, which would take around 3 years. [A][B][C][H][I][X]
Field surfing spacecraft Future spacecraft might surf the magnetic fields of Earth and other planets, taking previously unfeasible routes around the solar system, according to a proposal funded by NASA's Institute for Advanced Concepts. The electrically charged craft would not need rockets or propellant of any kind. It would be gently pushed by Earth's rotating magnetic field, enabling it to change orbit and even escape to interplanetary space. The craft could charge itself up by firing a beam of charged particles into space, or by allowing a radioactive isotope to emit charged particles. To hold enough charge, many long filaments could be attached to the spacecraft, standing out likely newly brushed dry hair. [A][P] |
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| [U] Unmanned vehicles and robotics | |
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Ethical code for robots An ethical code to prevent humans abusing robots, and vice versa, is being drawn up by South Korea in anticipation that robots will start to acquire strong intelligence in the near future. The Robot Ethics Charter will cover standards for users and manufacturers and will be released later in 2007. [U][V][W]
Robotic salamander In animals, the mechanics of walking, swimming, running and crawling are all coordinated by clusters of neurons in the spinal cord. These produce patterns of neural pulses that drive different muscles to produce the right movement without needing to involve the brain. This approach may also work well for robots. Swiss and French researchers have developed a robotic version of a salamander, which uses an electric "spinal cord" to control both its walking and swimming. They hope it will be a forerunner of many types of robots with movements coordinated by artificial nervous systems. [U][B]
Robotic surgery Engineers at Johns Hopkins have developed a motor that can be safely used in the very high magnetic fields needed for magnetic resonance imaging. The motor is made entirely out of plastics, ceramics and rubber, and driven by light and air. It can power remote-controlled robotic medical devices and the computer-controlled movements are steadier and more precise than is possible with a human hand. The ability to guide robotic instruments with MRI means that biopsies and therapies can be performed much more accurately. [U][H][P][R]
Microrobot propulsion Finding a propulsion mechanism that works on the microscopic scale is one of the key challenges for developing microrobots that could move around in the blood stream. Another is to find a way to supply such a device with energy because there is so little room to carry on-board fuel or batteries. Researchers from North Carolina State and the University of Hull have found that a simple electronic diode could overcome both problems. Applying an external alternating electric field induces a current within the diode. This in turn set up an electric field between the diode's electrical contacts and created the propulsive force. The force occurs because the field accelerates ions in the water in one direction, pushing the diode in the other, a phenomenon known as electro-osmosis. [U][P] |
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| [P] Propulsion and energy | |
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Regulating vehicle emissions The US Supreme Court has ruled that the US government was wrong to say it did not have the power to regulate exhaust gases from new cars and trucks. In one of the most important environmental cases to reach the Supreme Court in decades, the justices were asked to rule whether carbon dioxide should be defined as a pollutant and therefore subject to a law regulating emissions. Their ruling says that unless the US Environmental Protection Agency can show that carbon dioxide is not involved in the warming seen around the world, it should regulate it. [P][E]
Superconducting ship propulsion Researchers from Siemens have developed a superconducting engine for electric ship propulsion. The engine generates four megawatts of power at a torque of over 300 kiloNewton-metres. The rotor windings are made of high temperature superconductor that carries a current density 100 times greater than that in conventional copper windings, making the engine significantly smaller and lighter. The engine has an enclosed, self-regulating system, that cools the superconducting windings to 27 degrees K. According to Siemens, this provides cheaper cooling with low maintenance. [P][D][E][M]
Gas turbine research A new Gas Turbine Research Centre has been set up at Cardiff University to increase research in areas including air quality and emissions, particulates and cloud formation, and alternative fuels. Two major combustion rigs have been donated by QinetiQ, and funding has been provided by the EU for work on improving the design of gas turbines and testing cleaner fuels for the aviation and power generation sectors. As part of the EU work, the new facilities will test alternative liquid and gas fuels produced from biomass and waste gases, including methane, hydrogen mixtures, coal gasification products, and biofuels. [P][A][E]
Termite technology Currently the primary feedstock for ethanol produced in the US is corn. In 2006, nearly 2 billion bushels, representing one-fifth of the US corn harvest, were converted into 18 billion litres of ethanol. This was enough to meet 4 percent of the US fuel demand. However, diverting so much corn from food use pushed up prices to levels that caused food riots in Mexico. Researchers are therefore exploring many ways to make biofuel instead from woody plant matter. Approaches vary from devising chemicals to break down cellulose to genetically engineering plants that can be turned more readily into sugar. Many researchers are trying to copy how termites do it. Termites have a cocktail of hundreds of species of fungi and bacteria in their guts, and the enzymes these secrete enable termites to break down the hard, fibrous cellulose, lignin, and other materials that give plants and trees their rigid structures. [P][E][G][M][T]
Hybrid hydrogen-carbon fuel Researchers at Purdue University suggest that the best way to provide sustainable fuel for transport might be through a hybrid approach combining biofuel and hydrogen. In current methods for converting biomass or coal to liquid fuels, 60 percent to 70 percent of the carbon atoms are lost as carbon dioxide. If hydrogen were supplied from some other source, all of the carbon in the biomass could be captured as hydrocarbon fuel. This would make it easier to produce enough biomaterial for the system to be sustainable without using land needed for food production. The hybrid biomass-hydrogen approach would also avoid the technology hurdles and massive investment involved in switching to hydrogen power. These hurdles mean that it will be 2025 before hydrogen powered vehicles could be commonly produced and sold, according to BMW. [P][E]
Enzyme-based fuel cell At Oxford University, researchers have developed a biofuel cell that produces electricity from a non-explosive mixture of air and hydrogen. The cell uses enzymes called hydrogenases from naturally occurring bacteria that use or oxidize hydrogen in their metabolism. The cell consists of two electrodes coated with the enzymes placed inside a container of ordinary air with 3 percent added hydrogen. The cell offers a cheaper alternative to platinum-based fuel cells. [P]
Sugar-powered fuel cell A new type of fuel cell has been developed that produces electricity from sugar. The cell uses enzymes commonly found in living cells. The key was finding a way to protect the enzymes with polymers so that they remain active for months. Enzymatic fuel cells developed by other research groups typically run on more conventional fuels, such as ethanol. Direct use of sugars as fuel would be more energy efficient than fermenting corn, sugarcane, or other crops to turn their sugars into ethanol. The US Department of Defense, which is funding the research, is also interested in using sugar as a densely packed energy source on the battlefield. [P]
Cheap solar cells Copying the ability of the sea sponge to produce layers of silicon at room temperature, researchers at UCSB have developed a chemical process for growing crystalline layers of zinc oxide from 100 to 300 nm thick on a glass substrate. With this material they have succeeded in building primitive working solar cells and the hope is that this could lead to a breakthrough in reducing solar cell cost. The process is very cheap and avoids the high temperature deposition that makes current silicon solar cells expensive. [P][J][M][N][O]
Cheap solar cells Researchers at Massey University in New Zealand say they have developed a new dye-sensitised solar cell technology that could generate electricity ten times cheaper than current silicon-based cells. They report that 10 cm x 10 cm demonstration cells using a synthetic chlorophyll dye generate enough electricity to run a small fan in low-light conditions. The dyes can also be incorporated into tinted windows to generate electricity. [P][M][N][O]
Solar battery European researchers have combined a thin-film organic solar cell with a new type of polymer battery to produce a battery that recharges itself when exposed to natural or indoor light. Prototypes of the solar battery weigh as little as two grams and are less than one millimetre thick. [P][J][M][N][O][V] |
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| [M] Materials, structures and surfaces | |
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Electrically conducting plastic The discovery of conducting polymers won a Nobel prize in 2000. However, most plastics are insulating. This is because the movement of charge is hindered by the structure of the material, particularly by the ends of the polymer chains, fractures in the chains, and the chaos in and along the chains. Dutch research has now shown that a polymer produced by German researchers with a relatively fixed, ladder-like structure has an electrical conductivity 1000 times higher than normal plastics, similar to that of a semiconductor. [M][J][V]
Observing critical transitions Turning a gas into a Bose-Einstein condensate requires confining it in a magnetic field and chilling it to near absolute zero. Theory predicts that the new state will not appear abruptly. Instead, starting just above the critical temperature, bubbles of condensate fleetingly form and disappear, increasing in size as the temperature falls. At the critical temperature, the bubbles merge and the entire system becomes a condensate. Physicists at the Swiss Federal Institute of Technology and the University of Cambridge have now been able for the first time to observe this process experimentally - howbeit in reverse - by warming a Bose-Einstein condensate through its critical temperature at an extremely slow rate of only four billionths of a degree per second. The technique opens new possibilities for studying not only Bose-Einstein condensates but also general properties of criticality. [M][F][X]
Nanotubes enhance superconductivity Magnesium diboride (MgB2) has great potential thanks to its high critical temperature of 39 degrees K, its low cost and its simple chemical composition. What is holding it back is its low upper critical field of 14 to 16 Tesla and its low critical current density. Now, Argentinean and US scientists have succeeded in simultaneously improving these two parameters by doping the superconductor with double-walled carbon nanotubes (DWNTs). They found that adding around 3.5 atomic percent of DWNTs produced the best improvement, increasing the upper critical magnetic field by a factor of 3 and the critical current density by a factor of 2.5. The improvement is due to carbon doping and vortex pinning by the nanotubes. [M][N][P][R][S]
Structure of turbulent flow A comprehensive description of turbulent fluid motion remains one of physics' major unsolved problems. Researchers have long suspected that there is a coherent underlying structure in turbulence, but there has been no objective way of identifying it. Now researchers at MIT have developed a new mathematical techniques that provides a systematic way to identify the structural building blocks of a turbulent flow. To picture the skeleton of turbulence, the MIT researchers analyzed experimental data obtained from co-workers at the University of Texas. In the Texas work, complex turbulent flows in water were revealed using miniscule polystyrene spheres and laser illumination, providing a high-quality map of the whole velocity field of the turbulent flow at each time instance. The surprising finding from the MIT work is that the complicated, constantly evolving flow patterns are driven by two competing armies of particles constantly being pulled together and pushed apart. The MIT researchers call their discovery the "Lagrangian skeleton" of turbulence. [M][A][C][E][F][O][P]
Noise absorbing windows Whilst double or triple glazing can absorb high frequency noise, it is much less effective against low-frequency noise such as that produced by aircraft, traffic or bass tones of disco music. To reduce this problem, Fraunhofer researchers have developed an active noise-cancellation system for use on windows and walls. Tests have shown the windows can lower noise levels by an average of six decibels at frequencies between 50 and 1000 Hertz. The researchers believe that it should be possible to achieve up to 10db reduction of passenger aircraft engine noise below 1000 Hz. [M][A][E][P][S][W]
Theory of clogging Scientists at the French national civil engineering laboratory, studying the pouring of concrete through steel reinforcement mesh, have developed and experimentally verified a theory that describes how filters become clogged. The theory is based on the probability for particles to arrive simultaneously and jam together based on the number of particles in the flow and their size relative to the holes. The researchers believe that extensions of the theory, taking into account interparticle forces for example, could apply to a wide variety of natural and artificial filters. [M][N] |
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| [E] Environment, transport and marine | |
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Earth's magnetic field New measurements suggest that the Earth's magnetic field was nearly as strong 3.2 billion years ago as it is today. The findings suggest that even in its earliest stages the Earth was already well protected from the solar wind, which can strip away a planet’s atmosphere and bathe its surface in lethal radiation, as probably happened on Mars. The measurements were made using the best preserved grains of feldspar and quartz out of 3.2 billion-year-old granite outcroppings in South Africa. Feldspar and quartz are good preservers of the palaeomagnetic record because their minute magnetic inclusions record the magnetic field as they cool from a molten state. [E][A][M]
Plate tectonics A sliver of ancient sea floor discovered in southwest Greenland indicates that plate tectonics and the same processes of sea-floor formation and spreading seen today were well established 3.8 billion years ago, soon after the Earth formed. Previously the earliest evidence of plate tectonics was from rocks 2.5 billion years old. [E][M]
Climate sensitivity to carbon dioxide New calculations by geologists at Yale and Wesleyan University indicate that the sensitivity of Earth's climate to changes in the greenhouse gas carbon dioxide has been consistent for at least the last 420 million years. [E][P]
Changing local climates Within a century, half of the world's local climates will have vanished as a result of global warming, taking thousands of species with them, according to researchers at the University of Wisconsin, who have carried out the first global assessment of how all of the Earth's local climates will be affected. Disappearing climates are likely to be concentrated in tropical mountain regions and towards the poles. New types of local climate will emerge primarily in the tropics and sub-tropics. [E][C][D][H][X]
Deforestation The world should invest 10 billion dollars annually to halve deforestation in the fight against global warming, according to Nicholas Stern. Forest covers about 30 percent of the world's land area. From 1990 to 2005, three percent of the total forest area was lost, according to the UN. Ten countries account for 80 percent of the world's primary forests, of which Indonesia, Mexico, Papua New Guinea and Brazil saw the highest losses in the five years from 2000 to 2005. [E][P][X]
Preserving rainforest In 2002, the World Bank agreed to provide $90 million of development aid to the Democratic Republic of the Congo provided the government did not issue any new logging concessions. The deal also prohibited the renewal of existing concessions and required that the remaining concessions would be taxed and 40 percent of the taxes paid to communities local to the logged areas. In this way, the World Bank hoped that limited legal logging could be used as a way to help local communities develop. According to a new report by Greenpeace, the DRC's government has totally failed to redistribute the taxes to local communities and has also granted 15 million hectares in new concessions to international logging companies, in breach of the moratorium. Most of the timber is exported to Europe, with France and Belgium being the largest importers. Predictions for future deforestation estimate that by 2050 activities in the DRC will release roughly the same amount of carbon dioxide as the UK has emitted over the past 60 years. [E][D][R]
Pollution and water supply Communities in semi-arid regions rely on the water from rain and snow that fall on mountains, sometimes hundreds of kilometres away. But the air pollution emitted by the same people means that the some of the moisture in clouds is evaporating before it ever reaches the ground. This is particularly serious in parts of south-western US, in the Middle East and in China. At the meteorological station on Mount Hua in central China, researchers have found that on very hazy days, when visibility is less than 8 km at the mountain top, precipitation in the hills is decreased by 30 to 50 percent. China's rivers are also becoming gravely polluted, according to the Chinese Academy of Sciences. More than 370 miles of the Yangtze river, which accounts for 35 percent of China's total fresh water resources, are in critical condition, and almost 30 percent of its major tributaries are seriously polluted. China is expected to overtake the US as the world's number one carbon emitter in 2007. [E][D][X]
Ice sheet movement Just as the water flowing off warm landmasses reaches the sea via rivers, most of the ice spilling off Antarctica and Greenland is carried by ice streams that flow much faster than nearby ice. Many factors influence how fast these streams move: the temperature of the ice, the roughness and grade of the terrain underlying the ice, lakes and rivers of liquid water at the base of the ice, and barriers of moraine where the ice meets the sea. Ocean tides can lift the ice reducing friction and these tides produce daily and weekly variations in flow speed at some locations. The draining and filling of subglacial lakes and the climate cycles, such as ice ages, appear to cause variations over decades, centuries, or millennia. Much more needs to be understood about these factors in order to model more accurately how rapidly the Antarctic and Greenland icecaps could melt as a result of global warming. [E][C][R][T][X]
Arctic sea ice A new NASA study has found that in 2005 the Arctic replaced very little of the thick sea ice it normally loses and replenishes each year. Replenishment of this thick, perennial sea ice each year is essential to the maintenance and stability of the Arctic summer ice cover. [E][R]
2007 hurricane season Forecasters in the US and Europe are predicting that 2007 could mark a return to the destructive hurricane seasons of 2004 and 2005. Four strong hurricanes hit Florida in 2004, and the record-breaking 2005 season produced 28 storms including Katrina. In 2006, the Atlantic hurricane activity was much lower. The El Niño warm-water conditions in the eastern Pacific led to conditions that steered Atlantic storms away from ocean regions with high surface water temperature, preventing them from growing into hurricanes. Dust in the atmosphere may also have reduced the initial formation of storms according to NASA research. However, in 2007, the El Niño conditions have dissipated rapidly, and because of this and the warm water in the Atlantic forecasters are predicting there will be 17 tropical storms for the Atlantic basin as a whole. Of these, nine are expected to be hurricanes with four or five being Category 3 or higher. [E][C][R][X]
Risk of storm surges If global warming causes more intense storms, this may not necessarily lead to more devastating storm surges. Ocean sensors in the path of hurricane Ivan in 2004 revealed that as the wind increased it dragged the ocean currents faster. But, once the wind's speed exceeded about 32 metres/second, it started to generate breaking waves, sea spray and foam. This decreased the ability of the wind to drag the sea surface along and the currents slowed down. [E][R] |
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| [R] Remote sensing and sensor systems | |
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Global mapping of greenhouse gases ESA has released the first films to map out the global atmospheric distribution of carbon dioxide and methane. The maps are based on three years of observations by SCIAMACHY (Scanning Imaging Absorption Spectrometer for Atmospheric Chartography), the first ever space sensor capable of measuring greenhouse gases directly down to the Earth's surface. Data from the sensor, which is carried on ESA's ENVISAT satellite, has enabled the scientists to distinguish between columns of manmade carbon dioxide, such as the burning of fossil fuels, and the naturally occurring gas. This will help scientists to carefully monitor governments' efforts to meet their emission targets. The maps should also reveal more about different methane sources and sinks. [R][E][M][P]
High-resolution deep Earth seismology Some 2900 km beneath the Earth surface lies the boundary where the liquid iron of the outer core meets the silicate rock of the lower mantle. Researchers at MIT have adapted technology developed for near-surface exploration of reservoirs of oil and gas to image this boundary with sufficient lateral resolution to be able to observe significant structural features. The techniques exploits the way deeply propagating waves generated by large earthquakes are reflected back at the core-mantle boundary. By combining data from thousands of earthquakes recorded at more than 1000 seismic observatories, the researchers are able to detect and interpret the signals produced by underground structures and hence to pinpoint the details of deep earth structures. This could lead to a new era in deep Earth science and could also improve the ability to look for oil in or beneath geologically complex structures such as the Gulf of Mexico salt domes. [R][E][M][P]
Next generation radio telescope At the ALMA Test Facility in New Mexico, two prototype antennas and an electronic correlator have linked up to track and observe an astronomical object for the first time. ALMA (the Atacama Large Millimetre/submillimetre Array) will use up to 64 antennas when it becomes operational in 2012. Each antenna dish is 12 metres diameter and the total collecting area of the array will make it the world's most sensitive telescope at wavelengths of 0.3 to 9.6 mm. It is designed to look through dust clouds to reveal star formation, image embryonic planets and probe the early universe. The dishes will be movable, allowing baselines from 150 metres to 18 kilometres, with the longest baseline and the shortest wavelength giving resolution as fine as 0.005 arcsecond, a factor of 10 better than that of the Hubble telescope. [R][A][C][F]
Long wavelength array Astronomers at the Naval Research Laboratory (NRL) have produced the first images of the sky from a prototype of the Long Wavelength Array (LWA), a revolutionary new radio telescope to be constructed in southwestern New Mexico. Once completed, the LWA will provide an entirely novel view of the sky, in the radio frequency range of 20–80 MHz, currently one of the most poorly explored regions of the electromagnetic spectrum in astronomy. The LWA will be able to make sensitive high-resolution images, and scan the sky rapidly for new and transient sources of radio waves. It will also generate richly detailed measurements of the ionosphere that will complement other ionospheric data sources. The antenna design, which resembles a ceiling fan with blades that have drooped down at an angle of 45 degrees, allows the array to see the full sky and cover a wide range of frequencies with a single antenna. It is planned that the LWA will have over 13,000 individual antennas, divided into 50 stations spread across New Mexico. [R][A][I]
Adaptive optics Astronomers at the European Southern Observatory's (ESO) Very Large Telescope (VLT) have obtained their first corrected pictures of space with the Multi-Conjugate Adaptive Optics Demonstrator (MAD). 'The aim of MAD is to prove the feasibility and performance of new adaptive optics techniques critical for future instruments, both for the Very Large Telescope and the Extremely Large Telescope. [R][O]
Bats, radar and wind farms Research at the University of Aberdeen has found that bats appear to avoid the vicinity of radars. The finding is based on studying bats at various distances from 10 radar installations across Scotland. It is not known how bats detect the presence of radar, and what features of radar deter them. But the discovery could solve the problem of how to keep bats away from wind turbines. Bat deaths caused by wind farms are thought to exceed those of birds, according to US reports. With the growth in the number of wind farms and domestic wind turbines, this poses a serious threat to endangered bats species. [R][P]
Multi-angle imaging Nearly every current imaging system, from eyes to cameras, uses light reflected from a single narrow range of angles to produce an image. However, by shining light on an object from different angles, and then combining the light from these multiple angles, a system could provide much more detailed understanding of an object and particularly of its surface texture, imperfections and scratches. An engineer at the Imperial College has now designed such a multi-angle scanner. It uses low-cost optics and is aimed at applications in quality control and surface inspection. [R][M][O][S][W] |
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| [S] Sensor devices | |
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3D visualisation of yeast cell Researchers at the European Molecular Biology Laboratory (EMBL) and the University of Colorado have obtained the first 3D visualization of a complete eukaryotic cell at a resolution high enough to resolve the precise architectural plan of the cell's cytoskeleton. Of particular interest is the structure and behaviour of microtubules, the long, tube-like filaments that form a key structure of the cytoskeleton. They are dynamic structures built of constantly growing and shrinking rows of elementary proteins called tubulins. To increase their rigidity microtubules associate in bundles and interact with stabilizing proteins in complex networks, which are essential for many cellular processes. In mammalian nerve cells, microtubule bundles similar to those observed in yeast by the researchers, are essential for the transmission of the signal from cell to cell. [S][B][G][N]
Rapid detection of bacteria Scientists at Sheffield University have developed a way to rapidly detect the presence of bacteria. It uses specially designed molecules that change shape and emit fluorescent light when bound to bacteria. The technology could have wide applications in wound healing, counter-terrorism and screening patients for MRSA and other infections. [S][D][E][H][O]
Cheap biomolecule screening MIT researchers have created an inexpensive method to screen for millions of different biomolecules in a single sample. They say that the technology could lead to cheap clinical bedside diagnostics. The work, based on tiny customizable particles, could also be used for disease monitoring, drug discovery or genetic profiling. The particles are each equipped with a barcoded ID and one or more probe regions that turn fluorescent when they detect specific targets in a test sample. The particles flow through a microfluidic device that aligns the oblong, disk-like shape of the particles ensuring they are precisely aligned for accurate scanning. Each time a particle flows past a detector, its barcode is read and its fluorescence is measured. The researchers say that a virtually unlimited range of particles can be produced to test for DNA, RNA, proteins and other biomolecules. They can be produced efficiently in a single step making them inexpensive. [S][D][G][H][O]
Quartz Laser Photo-Acoustic Sensing Researchers at Pacific Northwest National Laboratory have produce a highly sensitive, compact, rugged sensor for detecting chemical warfare agents. In one test, using a chemical similar to sarin called diisopropyl methyl phosphonate (DIMP), the sensor was able to detect the DIMP at the sub-part-per-billion level in less than one minute. It is based on Laser Photo-Acoustic Sensing (LPAS) and infrared Quantum Cascade Lasers (QCLs). LPAS is an exquisitely sensitive form of optical absorption spectroscopy, where a pulsed laser beam creates a brief absorption in a sample gas, which in turn creates a very small acoustic signal. A miniature quartz tuning fork acts as a "microphone" to record the resulting sound wave. Using QCLs and the quartz tuning forks enables the instrument to be made much smaller than previously possible. [S][D][E][O][R] |
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| [O] Optoelectronics, optics and lasers | |
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Negative refractive index superlens Two US teams have independently created the first truly magnifying "superlenses" using metamaterials with a negative index of refraction. In a conventional lens, diffraction limits the resolution to around one wavelength. A superlens can beat the diffraction limit by making use of the evanescent waves from the object. These are the high angular frequency components of the light waves and contain the information about the small scale features of the object. In a normal material, these evanescent waves rapidly attenuate, but with a negative index they can propagate and brought to a focus. [O][M][N][S]
Double-negative metamaterial Researchers at Purdue have created a metamaterial that has both a negative magnetic permeability and negative electric permittivity for infrared light with a wavelength of 813 nm. The result is an important step towards creating double-negative negative-index metamaterials (DN-NIMs) that operate in the visible range. While metamaterials have been developed with negative permittivity for visible light, negative permeability is much more difficult to achieve because the magnetic interaction between light and a metamaterial is more than 100 times weaker than the electrical interaction. [O][M][N][S]
Optical cloak A design for an optical cloak has been proposed by researchers at Purdue. It uses an array of nanoscale needles radiating outward from a central spoke, resembling a round hairbrush. Simulations show these nanoneedles should bend light around the object being cloaked so that background objects would be visible but not the object inside the cloak. In principle, the cloak could be arbitrarily large, as large as a person or an aircraft. The present design works only for monochromatic light, but the researchers believe it should be possible in the future to produce a design that covers a wide range of colours. [O][D][M][N][R]
Near field beam steering Because of diffraction, the position of a light beam cannot normally be controlled to less than half its wavelength. However, the limit does not apply in the near field, where evanescent waves exist. German and Spanish researchers have exploited this to steer laser pulses with much higher precision. The researchers fitted a femtosecond laser with a polarization shaper that controls how the polarization of the femtosecond pulses changes with time. Firing the laser at a specially-designed nanostructure resulted in near-field interference effects that created a pattern of light and dark regions on the nanostructure. By varying the polarization of the laser pulses, the researchers were able to illuminate different regions of the nanostructure. The illuminated areas were less than 200 nm across, about one quarter the wavelength of the laser light. According to the team, the precise control of the laser light in time and space could be used in new spectroscopic methods, to steer nano-mechanical processes in optical traps, to control chemical reactions in large molecular aggregates, and in new schemes for quantum computing. [O][C][M][N][S]
Radiation pressure Scientists in France and the US have shown that radiation pressure from a laser beam can generate bulk flow in a fluid. The experimental liquid they used was a special mixture of water and oil that intensely reflected light. It is possible the technique might be useful for propelling fluid in a controlled way in microfluidic devices using radiation pressure. [O][J][M][S]
Einstein box Physicists at CNRS have created an Einstein box in which a single photon can be trapped and monitored from birth to death. The box comprises a cavity with walls made from ultra-reflective, superconducting mirrors able to trap a photon for about a seventh of a second. The photon can be monitored using a stream of rubidium atoms. When an atom crosses the photon's electrical field, this causes a tiny delay in the electrons that orbit the atom's nucleus, but without absorbing the photon. The delay is measurable by using the technique of modern atomic clocks, which use the electrons' orbit as a "pendulum" to provide a precise time. The result is of practical value for quantum computing as it demonstrates how a stream of atomic qubits can be controlled by the qubit state of a trapped photon. [O][C][M][R]
Few-atom nanolaser Dutch researchers have shown that, in theory, it should be possible to produce a nanolaser using just a few atoms, or even just two atoms. One atom is pumped and the other atoms nearby provide optical feedback through multiple scattering of light. If the atoms are in each other's near-field, the system exhibits large gain narrowing and spectral mode redistribution. This gain narrowing causes the laser to oscillate at just one frequency, removing the need for mirrors and a tuned cavity. [O][N]
LED lighting Osram has developed a small light-emitting diode spotlight that achieves an output of more than 1,000 lumens, brighter than a 50-watt halogen lamp. The Ostar Lighting LED, which will be launched on the market in mid-2007, can provide sufficient light for a desk from a height of two metres, and its small size also enables the creation of completely new lamp shapes. [O][E][J][P]
TeraHertz metamaterials Los Alamos scientists have shown how metamaterials can be designed to efficiently control THz waves. By using micro-fabrication processes to lay down an array of gold metamaterial structures over a semiconductor substrate, they produced a voltage-driven modulator that was able to modulate THz waves by up to 50 percent, better than any device previously demonstrated. [O][H][I][J][M][N][S]
TeraHertz filter Scientists at the University of Utah have found that they can transmit teraHertz light at selective wavelengths by shining it onto a metal film perforated in an aperiodic, "quasicrystal" pattern. As the THz waves pass through the perforations, they generate plasmon polaritons. These produce interference that blocks out some frequencies. The filters might be used for short-range wireless communications and might be tuned simply by being rotated. [O][I][R][S]
Very high bandwidth optical communications IBM has revealed a prototype optical transceiver chipset capable of reaching speeds of at least 160 Gbits/second. The chipset uses CMOS driver and receiver circuits coupled with III-V optical components, integrated into a package only 3.25 by 5.25 mm in area. [O][C][I][J] |
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| [I] IT, communications, networking and secure systems | |
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Skynet 5 The first of the Skynet 5 constellation of military communication satellites has been launched successfully. Skynet 5 has been funded through a Private Finance Initiative (PFI) between the UK MoD and Paradigm Secure Communications (PSC), a subsidiary of EADS Astrium. Under this agreement, Paradigm has built and launched Skynet 5 and has take over and operates the UK's military satcom network. Paradigm can also sell excess bandwidth - expected to be about 50 percent on each spacecraft - to NATO and other friendly countries. [I][A][D]
Real time action at a distance A reliable way to compensate for communication delays is needed for performing telesurgery over the internet and also for synchronising sophisticated virtual worlds that involve very detailed simulations. Researchers at the University of Manchester and the University of North Carolina have developed a technique to deal with this. Their system uses a "rollback" technique whereby, when a delayed message is received, the software calculates how things would have turned out if it had arrived on time and then alters the virtual world as subtly as possible so that these effects are expressed in the "true", real-time situation. The system also employs peer-to-peer networking to remove the delay in waiting for a response from a central server when a movement is made. The system proved successful in tests in which two users, on either side of the Atlantic, had to cooperate using haptic interfaces to fit a virtual fuel control box onto an aircraft engine. [I][C][D][H][U][V][W]
Wireless quantum cryptography Wireless transmission of quantum code over a distance of 144 kilometres between two Canary Islands has been demonstrated by European researchers. For additional security, the researchers not only used single photons but also entangled the outgoing particles of light with photons kept at the transmitting station. [I][O]
Bot network According to security firm Symantec, the number of computers hijacked by malicious hackers to send out spam and viruses has grown almost 30 percent in 2006. More than six million computers world wide are now part of a "bot network". [I][C]
Authentication of TSDs Although in the past memory devices such as floppy disks did not require authentication before a host read or wrote to them, security is now a much greater issue, e-commerce using mobile devices has blossomed, and transient storage devices (TSDs) such as USBs have much higher capacities. Therefore, enterprises want to authenticate TSDs before they permit a host to mount them. The IEEE 1667 standard, to be published in June 2007, has been developed to meet this need. IEEE 1667 defines bidirectional TSD authentication: the host can authenticate the TSD's identity, and the TSD can also authenticate the host's identity. [I][C] |
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| [K] Knowledge, information and technology management | |
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Smarter web Technology Review in March has published a two part review of approaches and progress towards developing a smarter web. [K][I][T][V][X]
Holding personal information The UK Royal Academy of Engineering has published a report examining the implications of new technologies for holding personal information, such as RFIDs, biometric passports, Web-2.0 and medical record databases. The report argues that although collection, storage and processing of personal data can be of great benefit to citizens, it could also do great harm if there is insufficient care and forethought about protecting privacy. Organisations should not seek to identify individuals if all they need is authentication of rightful access, the report says. More research is needed into ways that identity management technologies can fail, and effective contingency plans need to be devised. Systems should be designed so that there is transparency about the kinds of data collected and the intended use. Citizens need to be better informed about the capabilities of technologies that could have an impact on privacy. [K][D][I][J][T][V][X]
Strategy for RFIDs The European Commission has published the results of a public consultation on the strategy for RFID technology. The consultation covered issues of RFID use, privacy, data protection and security, standardisation and interoperability, radio spectrum, and research priorities. Privacy emerges as the top issue, with the need to extend data protection legislation to encompass RFID usage, especially as regards personal data. [K][I][J][T][W]
Personalisation Computer scientists at the University of Pittsburgh have developed a way to make e-mails, instant messaging, and texts more personal by allowing senders to use images of their own faces to communicate their mood. By automatically warping their facial features, they can use a photo of themselves to depict a range of different animated emotional expressions. [K][V]
Location-based information services Vehicle navigation and information systems could provide more pertinent and valuable location-based services to drivers as they travel around if the system could work out for itself where the driver is going and for what likely purpose. A "Predestination" algorithm developed by Microsoft can predict a driver's destination based on both general trends, such as the likelihood that people will choose various types of destinations, and personalized data such as a list of previously visited locations. It runs on a vehicle's navigation system and learns a driver's habits based on logged GPS measurements. [K][C][I][R][V]
Air quality forecasting service The city of London has launched an innovative service, funded by ESA, which delivers air pollution alerts and health advice via text messages to those who suffer from asthma and other conditions vulnerable to poor air quality. The Cambridge Environmental Research Consultants (CERC) developed the service using information from ESA’s PROMOTE project, which aims to improve air-quality forecasting using satellite technology. [K][A][E][H][R] |
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| [C] Computing, supercomputing, modelling and simulation | |
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Computational simplification The way that something seemingly obvious can go unnoticed for decades is well illustrated by the recent discovery at Lawrence Berkeley that the enormous computation time needed to simulate interactions between relativistic objects can be cut by a factor of a hundred or more by considering the interactions in the frame of reference of the moving particle rather than the stationary observer and accelerator. In a particle accelerator, a centimetre-wide pulse of particles can cover distances of many kilometres. This huge disparity in length scales makes computer simulations very time consuming. But in the frame of the particles, Lorentz contraction greatly shrinks this difference in scale. The simplification applies to free electron lasers and laser-plasma accelerators as well as to conventional particle accelerators. [C][O][P]
AI games As automated planning, machine learning and other AI techniques used in games become more sophisticated, game characters will be able to have deeper social interactions with the player. This could lead to new types of games and virtual living, depending less on violence and more on social and intellectual relationships. [C][K][T][U][V]
Massively multiplayer online games The market for massively multiplayer online games (MMOGs) in the West is now worth more than $1bn. New MMOG genres are emerging. These include: virtual world building games, such as Second Life; virtual pet rearing games, such as Neo pets; more casual MMO puzzle games; and eSports games in which players have to buy items and build up their character. It is predicted that more than 10 million people will subscribe to MMOGs by 2011, and many millions more will play online games driven by other payment schemes, such as advertising and virtual purchases. [C][D][E][K][R][T][V]
Networking world Sony has unveiled a 3D virtual networking world for the PlayStation 3 games console in which users can operate 3D characters and explore virtual settings. They have also previewed a game called "LittleBigPlanet" in which players need to collaborate to solve puzzles and can make modifications to the game to share with friends and other PS3 users worldwide. Both build on concepts from virtual worlds such as Second Life and from social-networking-sharing sites like MySpace. [C][I][K][V]
Intelligent swarm technology Nature-inspired intelligent swarm software deals with complex problems that might be impossible to solve using traditional technologies and approaches. An article in April IEEE Computer reviews some of the wide range of applications in bio-tracking, insect colonies, computer animation, data manipulation, unmanned underwater vehicles, micro-robots and pico-spacecraft. [C][A][E][K][T][U][X]
Architecture-adaptable system on a chip UCS and Raytheon have developed what they say is a revolutionary processor package that can continuously optimise its architecture to adapt in real time to the demands of different computing tasks. Called MONARCH (Morphable Networked Micro-Architecture), the system is aimed initially at applications such as space radar and video processing that require small size and low power. In preliminary tests, a prototype system consisting of just one of the new devices, provided sustained throughput of 64 gigaflops with more than 60 gigabytes per second of memory bandwidth and more than 43 gigabytes per second of off-chip data bandwidth. The researchers believe that the MONARCH computer is the most power-efficient processor available, outperforming the Intel quad-core Xeon chip by a factor of 10. [C][J][R]
Brain-like computers It may be easier to produce computers with human-like intelligence by copying the structure of the human brain rather than trying to use existing computer architectures that are very different. An article in IEEE Spectrum describes an approach called Hierarchical Temporal Memory (HTM). This mimics closely the structure and working of the brain's neocortex: strong use of hierarchy, the ability to recognise temporal sequences of data and to hierarchically handle sequences of sequences, and the ability to dynamically decide what to learn based on past and present experience. HTM builds on and extends several existing techniques, including Hierarchical Hidden Markov Models and Bayesian networks. It uses a very accurate mapping to the detailed anatomy of the neocortex. The model is particularly well suited to analysing and discovering patterns in large amounts of data especially where this has a hierarchical structure. [C][B][K][R][T][U][V][W]
Human and computer vision Computers can usually out-compute the human brain, but there are some tasks, such as visual object recognition, that the brain performs easily yet are very challenging for computers. During normal everyday vision, the eye moves around a scene, giving the brain time to focus attention on relevant cues. However, evolution has also equipped the brain with the ability to extract vital information in one glance in order to react instantly to danger. Researchers at MIT have developed a computer model that can match human performance on such rapid visual tasks. The model mimics very closely the organization of the brain's visual system and even tends to make similar errors as humans. The results showed no significant difference between humans and the model. Both had a similar pattern of performance, with well above 90 percent accuracy for the close views dropping to 74 percent for distant views. This drop is thought to represents a limitation of the single feed-forward visual sweep in dealing with clutter. [C][B][V] |
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| [W] Whole life engineering, manufacture and testing | |
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Interplanetary logistics Logistics planning software that works out how to schedule the delivery of supplies to several distant space bases has been developed by US researchers. It works in a similar way to systems used by international courier firms to co-ordinate deliveries. It uses the requirements of different bases, the capabilities of different vehicles, and changes in the relative position of bases and the gravitational pull of planets. It can juggle supplies to bases on the surface of planets, in orbit around them, and at Lagrange points - where the gravity between different bodies cancels out. It is currently being used to study the delivery challenges involved in building long-term bases on the Moon and Mars. [W][A][C]
Product anti-counterfeiting Counterfeit medicines can be harmful or fatal to users. They also undermine disease control in countries which are already stretched thin with limited resources for health care. To tackle this problem, the International Medical Products Anti-Counterfeiting Taskforce (IMPACT) was set up in 2006. Various technological approaches are possible, but as yet there is no easy answer. Overt verification tools, including holograms or colour-shift inks, are cheap but relatively easily copied. Covert tools, such as invisible printing and digital watermarks, are more expensive and require special devices to check. Chemical or biological tags built into medicines packaging are even more secure against copying but significantly more costly and provide no visible reassurance to customers. Serialization or track/trace systems, using bar codes and radio frequency identification (RFID), help provide authentication by allowing a medicine to be tracked through the supply chain, but these require an expensive technical infrastructure and are not completely immune to “hacking”. [W][D][H][I][J][K][V]
Production efficiency Artificial intelligence software that provides expert advice on improving the efficiency of a complex production line has been created by researchers in the UK. The software analyses the relationship between an end product and the many variables in the production process. Companies that cast metal parts, including Rolls Royce, have already begun using the software to reduce waste. Called X1 Recall, the program can learn what affects the quality of a final piece of metal and suggest ways to improve production. [W][C][K] |
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| [X] Systems, complexity and risk | |
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Impacts of climate change The IPCC has published the second part of its four part report on climate change. This part concerns the relationship between observed climate change and recent observed changes in the natural and human environment. The report says that more specific information is now available across a wide range of systems and sectors and the magnitudes of impact can be estimated more systematically for a range of possible increases in global average temperature. Even the most stringent efforts to mitigate carbon emissions cannot avoid further impacts of climate change in the next few decades, and much more attention to adaptation is essential, particularly in addressing near-term impacts. The impacts will be worst in the poorest countries, and the need for action may be less compelling in rich northern countries. Some areas, including northern Europe, Canada and parts of the US, may actually benefit from a modest amount of warming. [X][A][C][D][E][H][P][R][W]
Carbon trading Since its launch in January 2005, the EU carbon trading system has grown into a market totalling nearly US $20 billion, providing a model for countries seeking to limit carbon dioxide emissions. It has also exposed some of the pitfalls in establishing such trading systems. The price for the right to emit a metric ton of carbon has fluctuated from a high of 30 euros per tonne in early 2006 to a low of 3.40 euros per tonne in January 2007, amid much controversy about the system’s basic design and regulation. The big problem has been from the Clean Development Mechanism, an institutional element of the Kyoto programme under which entities in industrialized countries can purchase carbon emissions credits by investing in approved emissions reductions projects in developing countries that are not subject to Kyoto emissions targets. [X][D][E][P][W]
Climate risk The western US may be heading towards the dustbowl landscape that devastated the prairies of the 1930s, according to climatologists at Columbia University. The team employed 19 major climate models used by the IPCC. The models show that sea surface temperatures up to 40 degrees north and south of the equator will continue to rise. Storms will follow the warming waters into the higher latitudes, dragging behind them the dry air that currently settles over the world's deserts. The models predict almost permanent drought conditions in western US, with rainfall reducing by about 3.6 centimetres each year until 2150. If the models are accurate, other semi-arid areas like those in eastern Australia, southern Africa, and the Mediterranean are similarly at risk. Los Angeles is going through its longest dry spell in at least 130 years. In Australia, the Murray-Darling Basin, which accounts for three-quarters of the total area of irrigated crops and pastures and around 70 percent of all water used for agriculture in Australia is now close to running out of water for irrigation. [X][C][D][E]
Coastal risk from climate change Thanks to a massive effort to gather 2002 population censuses from around the world, the Institute for Environment and Development in London has produced the first global map of populations at serious risk of flooding and storms exacerbated by climate change. The map shows that a tenth of the world's population, including one in eight city-dwellers, lives in the "at risk" zone less than 10 metres above sea-level and near the coast. The ten countries with the largest population at risk are: China, India, Bangladesh, Vietnam, Indonesia, Japan, Egypt, the US, Thailand, and the Philippines. [X][D][E][R]
Crowd behaviour The physics of pedestrian flows could help prevent stampedes such as the one that killed hundreds during a pilgrimage to Mecca in 2006. In normal conditions, pedestrians tend to spontaneously fall into ordered patterns, such as lanes going in opposite directions. As crowds get denser, stop-and-go patterns begin to propagate in waves, as is typical for cars on heavily trafficked highways. But in critical situations, people can break out in panics that result in random patterns of motion, similar to the turbulence of water in the wake of a boat. Crowd members can get squeezed and asphyxiated or fall and be trampled. [X][B][C][D][T] |
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| [V] Virtuality and human-machine interface | |
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Mini-projectors Several companies are aiming to incorporate mini-projectors into mobile phones. Various forms of small projectors, as integrated or separate units, could be available by early to mid 2008. [V][I][K]
Parallel ink-jet printing Typical inkjet printers use a nozzle that passes back and forth along a horizontal axis, spraying ink along the surface of the paper. An Australian company, Silverbrook Research, has now demonstrated a printer that instead uses an array of ink jet nozzles that spans the width of the paper. The company plans to sell A4 colour inkjet printers by the end of 2008 that will cost less than $200 and print 60 pages a minute. If successful, this technology could transform many printing applications. [V][I][K]
Shape memory clothes Philips has come up with a way to change the size, shape and style of clothes by weaving "muscle wires" into the fabric. The wires are made of shape-memory alloys that change length according to the small current passed through them. [V][M]
Smart fabric A New Zealand company has developed a smart fabric that gathers information on heart beat, skin temperature, posture, activity and breathing rate when against the skin. The technology is aimed at military, health and sports applications. [V][D][H][I][S]
GPS aid for the blind A satellite navigation system is being tested in northern Italy to help blind people find their way. The system uses a mobile phone, a small Bluetooth GPS receiver, text to speech software and an always-available call centre. It requires just two dedicated keys on the mobile phone - one, when pressed, tells the user their exact location including the house or building number; the other one alerts the call centre that the person needs assistance with navigation. [V][R] |
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| [B] Brain research and human science | |
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Controlling neurons with light US and German researchers have demonstrated a technique to directly control brain cell activity with light. The technique involves inserting two genes for producing light-sensitive proteins into cells of interest. One gene ChR2, derived from an algae, makes affected neurons more active when exposed to blue light. The other gene NpHR, taken from a microbe, can make neurons less active in the presence of yellow light. In experiments in living mouse brain tissues, the researchers made neurons signal when exposed to blue light or stop when exposed to yellow light on a millisecond timescale, just as they do naturally. Cells appear to suffer no ill effects from exposure to the light, and resume their normal function once the exposure ends. The results are a key step towards mapping neural circuit dynamics on a millisecond timescale in order to see if impairments in these dynamics underlie psychiatric symptoms. [B][G][H][O][V]
Mapping the brain in 3D Austrian researchers have developed a method called "ultramicroscopy" that renders brain tissue transparent. Using rodents genetically engineered to produce fluorescent molecules in their nerve cells, the team extracted whole mouse brains, submerged them in alcohol to flush the water out of the tissues, and then placed the dehydrated brains in a medium that had exactly the same refractive index as protein. This enables light to pass right through the brain without distortion. By shining a thin sheet of light, 6 microns thick, through the brain, they caused all the neurons in the sheet to fluoresce. By repeating this, they produced cross-section images through the whole brain, to give a 3D computer-based image of how all the nerves connect. [B][C][O][R][V]
Sleep-deprived performance Some people are “larks” and generally go to bed early, while others are “owls” and typically stay up late. Previous research has found that larks generally carry a long version of a gene PER3 whereas owls carry a short version. A new study has found that the PER3 gene also affects how people perform when deprived of sleep. After staying awake all night, individuals with long PER3 only scored half as well on cognitive tests as subjects with short PER3. The greatest differences were in the early hours of the morning, the time when most tiredness-related accidents happen. The study also suggests that people with short PER3 may have less need for deep sleep. Although both groups normally slept for about the same amount of time, subjects with the long PER3 gene spent roughly 22 percent of this time in restorative deep sleep whereas those with short PER3 spent around 15 percent. [B][D][G][H][W][X]
Sleep cycles and mental health Mice with a gene mutation that disrupts their sleep cycles show signs of hyperactivity and addictive tendencies, a new study reveals. Researchers say that such "manic" behaviour displayed by the animals bolsters the theory that glitches in the body's internal clock can cause psychiatric illnesses such as bipolar disorder. Mice that received injections of DNA to compensate for the mutated gene regained regular sleep cycles and showed normal behaviour. [B][A][D][G][H]
Erasing traumatic memories When memories are first made, they are sensitive to disruption for a certain time until they are stored in a stable, long-term state. However, when events are recalled from long-term memory, they become sensitive again to disruption and may be updated before being stabilised again for long-term storage. Scientists have now shown in experiments on rats that it is possible to take advantage of this sensitivity to erase the memory of a traumatic event, while leaving other associated memories intact. The researchers hope their findings will lead to treatments for post-traumatic stress in humans. [B][D][H]
Moral judgement Research at the University of Southern California shows that people with damage to a key emotion-processing region of the brain also make moral decisions based on the greater good of the community, unclouded by concerns over harming an individual. The study demonstrated how emotion impacts moral judgement and sheds light on why people often act out of respect for an individual rather than choosing to act in a more logical, utilitarian way. The findings could cause a rethink in how society determines a "moral good", and challenge the 18th-century philosophies of Immanuel Kant and David Hume. [B][D][E][K][X]
Alzheimer vaccine Japanese scientists report that they have developed an oral vaccine for Alzheimer's disease that has proven effective and safe in mice. The vaccine is made by inserting amyloid-producing genes into a non-harmful virus. The virus stimulates the immune system to attack and break down the amyloid proteins in the brain. This successfully reduced the amount of amyloid plaque in mice that had an Alzheimer condition, and improved their mental function. [B][G][H] |
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| [H] Healthcare and medicine | |
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Heart valve grown from stem cells UK scientists have succeeded in growing a human heart valve from stem cells. They extracted the cells from bone marrow, cultivated them into heart valve cells, and placed them in scaffolds formed from collagen. The cells grew into discs of heart valve tissue 3 cm wide. Later in 2007 these will be implanted into animals such as sheep or pigs to see how well they fare. The researchers believe that within the next decade it should be possible to grow a whole human heart from stem cells. [H][G][M]
Disc transplants Spinal discs from dead donors have been successfully transplanted into five people suffering neck problems, doctors in China report. Spinal discs are made up of cartilage and fibrous tissue and have a jelly-like centre that acts as a shock absorber between vertebrae. The centre has no blood supply, and no immunosuppressant drugs were needed. This success could lead to innovative treatments for debilitating back disorders, such as severe degenerative disc disease. [H]
Artificial immune system An artificial lymph node has been transplanted into mice, where it successfully produced immune cells. The researchers started with a "bioscaffold" made of collagen impregnated with stromal and dendritic cells extracted from the thymus of newborn mice. They implanted this into healthy mice where it attracted T and B immune cells (lymphocytes) that were already circulating in the healthy mouse, then organised them into compartments segregated from one another, just as they appear in natural lymph nodes. After the artificial node had filled with antigen-specific T and B cells, it was transplanted into a mouse with no functioning immune system. In the future, this technique might lead to transplanting an entire immune system into patients with AIDS, cancer or other diseases. [H][G][M]
Stem cell therapy for diabetes Brazilian and US scientists have used transfusions of patients' own stem cells to reverse type 1 diabetes. The results are encouraging that stem cells might provide a cure for type 1 diabetes, but the mechanism involved is not clear. It is possible that by generating new immune cells or some other means, the stem cells may have rebuilt the patient's immune system and thereby helped to safeguard what residual insulin-producing beta cells the patient had left in the pancreas. It is also possible that the stems cells may have led to the growth of new beta cells. [H][G]
Universal blood The A and B antigens, which give blood groups their name, are sugars carried on the surface of red blood cells. Human red blood cells can carry one of these antigens, both, or neither; giving four blood groups: A, B, AB and O, respectively. Danish and French researchers have found two bacterial enzymes that can remove the sugars responsible for the A and B antigens and thereby convert A, B and AB blood to blood Group O. Blood also contains antibodies in the serum against the other antigens. So type A has anti-B antibodies, type B has anti-A antibodies, type O has both and type AB has neither. This means that scrubbed type A, B or AB blood is even more universal than normal type O, because it lacks some or all of the antibodies as well as all of the antigens. [H][D] Combating TB According to the WHO, the global tuberculosis (TB) epidemic has levelled off for the first time since TB w | |||