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Top Stories in Science
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February 2007 Issue |
| [D] Defence and security |  |
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What is stopping a pandemic? It was thought in 2006 that what is stopping bird flu from causing a pandemic is that it does not infect the nose and throat in humans, only the deep lung. New research now shows this explanation is too simple. It is true that bird flu haemagglutinin prefers to binds to a sugar called 2,3-sialic acid that mammals have deep in their lungs, whereas flu adapted to mammals attaches better to 2,6-sialic acid, which mammals have in their nose and throat. However, scientists in Hong Kong have now found that bird flu is in fact able to infect the nose and throat in humans, and scientists at the US Center for Disease Control have shown that this infection does not by itself make the virus transmissible. Something else is needed. The CDC team believes this must involve the ability to bind to 2,6 sugars. But what this 2,6 binding does is not clear. Some evidence suggests it may cause sneezing and this may be what is crucial for transmission. To be able to bind to 2,6 sugars, the existing H5N1 bird flu virus needs just two amino acid changes in its haemagglutinin. It is these mutations that need to be watched for. [D][G][H]
Lethality of Spanish and H5N1 flu In a study of non-human primates infected with the H1N1 Spanish influenza virus that killed 50 million people in 1918, an international team of scientists has found that the infection prompts an immune response that seems to derail the body's typical reaction to viral infection and instead unleashes an attack by the immune system on the lungs. The same excessive immune reaction is also seen with the current H5N1 bird flu virus. The virus appears to do something early in the infection that enables it to grow very rapidly and to derail the immune response. But what this is remains unclear. [D][H]
Pandemic contingency planning During an influenza pandemic, workplaces are likely to experience high levels of absenteeism. Some companies are developing detailed contingency plans, including having key staff living isolated at work. Security will be a big issue if food and energy supplies are scarce. Many companies do not have the option of shutting facilities down: energy supply, food distribution and IT services all need to be kept operational. The UK Financial Services Authority has published the results of the world’s largest pandemic simulation. More than 70 organisations and 3,500 people took part in the six-week exercise run during autumn 2006. Participating companies were presented with absenteeism rates rising from 15 percent up to 49 percent with clusters briefly touching 60 percent. One finding was that home working is a good approach for some business activities, but tasks that depend on powerful mainframe applications and very low levels of application latency are likely to be problematic from a home base. The broadband infrastructure may also not hold up to a major increase in demand for teleworking. [D][H][I][K][P][W][X]
Rainforest war Ruthless illegal loggers are destroying the tropical forests of Southeast Asia, according to the UN. The Indonesian government says that illegal logging is now ravaging 37 of the country's 41 national parks, and accounts for three-quarters of all logging in Indonesia. Without urgent action, 98 percent of remaining forestation on the islands of Sumatra and Borneo could be gone by 2022. The Indonesian army is being defeated by the loggers, who are backed by a shadowy network of multinational companies and are often protected by heavily armed militia commanded by foreign mercenaries. Economic action may be the only hope, and the Indonesian government has appealed to the conscience of the whole world not to buy uncertified wood. [D][E][R][X]
Psychological effects of terrorism Terrorist attacks have widespread effects on people's mental health even when they are not directly involved or are far away at the time, according to researchers at University College London. They found that after an attack in an urban area, 11 to 13 percent of the general population may suffer post-traumatic stress (PTSD) during the following six weeks. Of those directly affected by terrorist action, 30-40 percent are likely to develop PTSD and at least 20 percent still experience symptoms two years later. These include intrusive memories and nightmares, sleep disturbance, and irritability. [D][B][H]
Non-lethal weapons Among the non-lethal weapons being developed by the US Department of Defense is a microwave heat-beam weapon that could be used to control mobs or repel foes in conflicts like Iraq and Afghanistan. This so-called Active Denial System causes an intense burning sensation, forcing people to run for cover, but does not cause lasting harm, according to the DOD. The weapon, which has been publicly demonstrated, is mounted on a Humvee and uses a large rectangular dish antenna to direct the microwave beam toward a target. It is claimed to be effective at more than 500 metres. As well as active weapons, the DOD is also looking at passive denial systems such as plastic material that can be sprayed on roads and behaves like very slippery black ice. [D][P][R]
Antimine weapon A novel countermine projectile being developed for the US Navy could neutralise mines underwater or underground more effectively, its developers claim. The projectile is a special version of the GPS-guided Joint Direct Attack Munition (JDAM) missile. It contains thousands of "Venom" darts, each 15 cm long with a hardened tungsten nose and a payload of liquid diethylene triamine (DETA), a strongly alkaline chemical substance. These darts are fired down as a shower and penetrate the surface to destroy the mines physically and chemically. The missile, which currently is released from an aircraft above a minefield, is primarily designed to clear mines in the "surf zone" between deep water and dry land, but can also destroy mines buried underground. [D][A] |
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| [A] Aeronautics and space | |
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Bat flight Understanding how bats fly could help in designing tiny flying vehicles, such as those being developed for military reconnaissance. Conventional wings do not work well at such small sizes and the aerodynamics is also not well understood. Wind tunnel experiments have revealed that the stretchy skin on a bat’s wings interacts with air differently compared to the firmer wings of birds and insects, deforming in ways that give more lift at higher angles of attack. This may allow bats to fly more efficiently and reduce the risk of stalling at low speeds. The wings’ elasticity, combined with dozens of joints, also allows bats to generate unusual shapes and motions, such as folding the wings very close to the body to reduce drag. [A][D][R]
Wireless networks in aircraft Boeing has abandoned its plan to use a wireless network to deliver in-flight entertainment on the 787 "Dreamliner". This is because of problems of weight and available spectrum. Boeing could not get permission to use certain frequencies in some countries. Also, a wireless network added 200 pounds per plane, rather than 50 pounds for a wired network. [A][I]
Inflatable spacecraft Genesis 1 - a prototype for an inflatable space hotel - was launched in July 2006 and is in orbit at an altitude of 560 km. It is 4.4 metres long and 2.5 metres in diameter, and is about one-third the size of the habitable modules that the space entrepreneur Robert T. Bigelow hopes to begin launching around 2010. The inflatable walls are multilayer structures, tens of centimetres thick, that together provide thermal control, structural strength, an absolutely airtight seal, and protection against space debris on the outside and scuffing on the inside. The inflatable-module is more rugged compared with conventional rigid-walled modules, and it should also be 25 to 50 percent cheaper to build and launch. The power, control, communication and other flight systems have been adapted from existing aerospace systems to reduce risk. Genesis I is equipped with two different means of performing all critical functions in order to provide dissimilar redundancy and to test which work better. It is in an orbit with 7 to 13 years life and can be tested over a long period. The next prototype, Genesis II, will be launched later in 2007. [A][M][T][W]
Protecting against space weather If a satellite encounters high-energy particles or other 'space weather' phenomena before ground controllers can take action, on-board electronics can be disrupted, scientific instruments damaged and, in very rare and extreme cases, spacecraft may even be lost. Since 2005, a space-weather monitoring and forecasting tool called SEISOP (Space Environment Information System for Operations) has been successfully providing near-real-time space weather reports for Integral, ESA's gamma-ray space observatory. SEISOP has been developed at ESA's Space Operations Centre and uses data from ESA, NASA, NOAA and other sources. In 2007, SEISOP will enter operational development to give all ESA missions the same space weather updates. [A][E][I][R]
Protecting against space weather Future lunar astronauts could be harmed by X-ray outbursts from the Sun that occur without warning and can deliver dangerous doses of radiation in just a few minutes, according to a new study. The researchers suggest that lunar rovers be equipped with metal shields that astronauts could duck behind during such events. Using the observed rate of solar X-ray outbursts of different magnitudes, they estimate that a lunar astronaut has a 10 percent chance of receiving a dose of X-rays exceeding 0.1 Gray from a solar flare for every 100 hours of activity outside of shelters. This level of radiation can cause bleeding ulcers and other internal damage, and would certainly increase an astronaut's risk of cancer. [A][H]
Life on Mars Biologists at UCL have calculated that if life still exists on Mars, it probably lies in areas with water and at a depth of 10 metres or more below the surface in order to be sufficiently protected from the harsh space radiation on Mars. They suggest that the most favourable place to find life may be in a region called Elysium that lies near the equator and appears to have blocks of water ice just beneath the surface. Unfortunately, none of the Mars missions currently being planned could drill down to a depth of 10 metres. Europe's ExoMars mission, planned for launch in 2011, will search for signs of life – such as fragments of DNA – that may exist at shallower depths. It will be able to drill down 2 metres into the soil. [A][U]
Water on Mars Data collected by the European Mars Express spacecraft has shown that, contrary to previous belief, only a small amount of water vapour and carbon dioxide in the Mars atmosphere has been lost to space over the past 3.5 billion years. This suggests that a great amount of water must be buried under the surface of Mars. Another possibility is that an asteroid or some other large object hit Mars in the distant past and literally knocked off its atmosphere and large bodies of water. [A]
Water planets Embryo planets that form far from a star, such as Pluto and comets, are composed mostly of water ice. If they exceed about ten Earth masses, they can gravitationally attract hydrogen and helium and then grow into gas giants like Jupiter, Saturn, Uranus and Neptune. However, if they are smaller and sufficiently close to the star, they could be covered by an ocean of water hundreds of kilometres deep. Although no such ocean planets exist in the Solar System, they should be quite common around other stars and should be detectable by the Corot satellite, which is just beginning its search for extraterrestrial planets. [A][R] |
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| [U] Unmanned vehicles and robotics | |
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Insect navigation Insects and other flying animals are somehow able to maintain appropriate flying heights and execute controlled takeoffs and landings despite lacking the advantage of sophisticated instrumentation available to human aviators. Tests using a microhelicopter suggests that insects use optical flow to keep at the right height. Essentially, the higher the insect, the slower the ground will appear to move below as it flies along, enabling it to gauge its height. Small robot aircraft might use the same method. [U][A][R]
High altitude helicopter An unpiloted helicopter that will function as an air ambulance on high mountains is being developed in New Zealand. Tests on the aircraft, called the Alpine Wasp, will begin in April 2007 in the Southern Alps, and around Mount Everest in January 2008. Conventional helicopters struggle at altitudes above about 4300m. The Alpine Wasp will have extra wide blades to provide more lift and an engine modified to cope with the thinner air. It will also spin its rotors at a lower speed than normal to avoid the rotor blades breaking the sound barrier in the thinner atmosphere. The helicopter will be remotely controlled by a pilot in a virtual reality environment. [U][A][V]
Biomimetic machine vision Researchers at MIT have shown that imitating the brain can result in useful pattern recognition. They applied a computational model of how the brain processes visual information to the complex, real world task of recognising objects in a busy street scene. Compared to traditional computer-vision systems, the biological model was surprisingly versatile in learning to detect widely different types of objects. The model mimics the brain's own hierarchy. The "layers" within the model replicate the way neurons process input and output stimuli in accordance with neural recordings in physiological labs. Like the brain, the model alternates between computations that help build an object representation that is increasingly invariant to changes in appearances of an object in the visual field and computations that help build an object representation that is increasingly complex and specific to a given object. [U][B][R]
Sniffer-bot algorithm Researchers at the Pasteur Institute in Paris have created an algorithm that tells a robot how to move in order to gather as much olfactory information as possible. This allows it to home in on even the faintest of scents. The researchers tested the algorithm using computer simulations. They used both real and simulated data on scents floating through turbulent air, and let a virtual robot loose to try to find the source of the smell. The researchers say that the algorithm could be useful for many tasks that involve searching with limited information, not only for robots and remote sensing but also, for example, in finding the ideal branches to use when sending data through a network. [U][C][I][K][R][S]
Bacteria-propelled microrobots Many bacteria propel themselves along in a fluid by rotating their corkscrew-like tails, called flagella, at relatively high speeds. These flagella are around 20 nanometres in diameter and are about 10 microns long. Motors made from bacterial flagella have been used as novel "nano-actuators". Now US researchers have shown that it is possible to use complete bacteria for propelling micron scale objects. The researchers conjecture that such hybrid swimming micro-robots might be used to deliver drugs inside the human body, such as in the urinary tract, eyeball cavity, ear and cerebrospinal fluid, and that they might also be employed to monitor toxic or pathogenic biochemical agents in the environment and to inspect and maintain liquid filled pipes in spacecraft and nuclear plants. [U][A][E][H][N][P][R][S] |
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| [P] Propulsion and energy | |
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Serial hybrid car GM has demonstrated a serial "plug-in" hybrid electric vehicle, the Chevy Volt, that it will start producing in 2010. In a serial hybrid, the wheels are powered by the battery and the engine is merely used to recharge the battery to give longer range if needed. The Volt is a 4-door family car designed to go about 40 miles on a single charge. This is enough to cover many drivers’ daily requirements without ever engaging the 1.0-litre engine, and the battery will normally be charged from the electricity supply. To make the concept into a successful production car, GM will need automotive-strength lithium-ion batteries that can operate over a wide temperature range, survive collisions and last for 10 years through 4000 deep discharge cycles. [P][E][M]
Efficient small fuel cells Chemical engineers at Princeton University have developed a new type of fuel cell that could be more practical for small machines like lawnmowers and chainsaws. The design allows the cell's output power to be controlled just by the rate of fuel input, as in an internal combustion engine, and enables the power output of the cell to be throttled back without reducing efficiency or requiring complex systems for control and recirculating fuel. The cell achieves this by collecting the waste water produced in the cell and using this to submerge part of the cell anode. If higher power output is needed, increasing the hydrogen flow pushes down the water level to expose appropriately more of the anode, matching the size of the reaction chamber to the power output this is needed. [P][D][E]
Semiconductor nuclear batteries A US company is developing a nuclear battery that uses an alpha-particle emitter and a liquid semiconductor. Using a liquid semiconductor avoids the problem of radiation damage since the liquid is self-healing. A liquid nuclear diode could catch energetic alpha and beta particles, gamma rays, and even the new atoms left over from the fission of larger atoms. Fission fragments could be a particularly good source of energy. In the fission of U-235, for example, the fragments carry 85 percent of the energy released. Because the fragments are heavy, they make a shower of electron-hole pairs along their path as they plough through the semiconductor. The efficiency of the battery is currently less than 1 percent, but the concept has potential both for batteries and for reactor-scale power plants. [P][D][E][M]
European Energy Action Plan The European Commission has proposed an integrated European Energy Plan under which the EU would pledge now to cut emissions by 20 percent and would push in future international negotiations for a 30 percent cut in developed countries by 2020. The energy action plan has three pillars: increased energy efficiency; a truly free internal energy market, where users have their choice of suppliers among all European suppliers; and, an accelerated shift to low-carbon energy so that at least 20 percent of energy comes from renewables by 2020 with at least 10 percent of vehicle energy coming from biofuels. The plan proposes that all new carbon-fuelled power stations will be carbon neutral by 2020 through carbon capture and sequestration. As well as reducing carbon emissions, the plan is also aimed at improving European security by reducing dependence on imported fuel. [P][D][E][T][X]
Roadmap for renewable energy Half of the world's energy needs in 2050 could be met by renewables and improved efficiency, according to a study by the German Aerospace Centre, which was commissioned by Greenpeace and Europe's Renewable Energy Council. The study concluded that alternative energy sources, such as wind and solar, could provide nearly 70 percent of the world's electricity and 65 percent of global heat demand. It excludes carbon-free coal power plants and nuclear energy and is based on a scenario of steady worldwide economic growth and the need for secure affordable energy. In the shorter term, the report concludes that renewable energy could provide as much as 35 percent of the world’s energy needs by 2030, if there is the political determination to promote large scale deployment in all sectors on a global level and if this is coupled with far reaching energy efficiency measures. [P][D][E][T][X]
MIT report on geothermal energy Geothermal energy generates nearly 10 gigawatts of electrical power worldwide, mainly from naturally-occuring hydrothermal sources. Such sources are rare and largely utilised, but geothermal power could be vastly increased artificially by pumping water through region of high temperature rock at depths ranging from 3 to 5 km. The potential of such Enhanced Geothermal Systems (EGS) is analysed in a major report by MIT. EGS extraction involves hydraulically fracturing rock volumes of several cubic kilometres and drilling into these regions to establish connected reservoirs. Five fundamental concerns - flow short circuiting, need for high injection pressures, water losses, geochemical impacts, and induced seismicity - all appear to be resolved or manageable. The major impediments now are the cost of drilling to such depths and the lack of knowledge about the underground rock-fracture systems, and how reservoirs will behave under fracturing and production. Breakthroughs could come from new drilling technology and better heat extraction, perhaps using fluids other than water, such as supercritical carbon dioxide. [P][E][M][T][X]
Sustainable biofuels A report by the International Institute for Environment and Development has mapped the obstacles in the way of sustainably developing biofuels. The novelty of biofuels, the vast array of issues involved, the lack of knowledge to tackle many of them, and the diverging political and business interests all mean that consensus is elusive. The report calls for international trade barriers, especially subsidies, to be relaxed to enable developing countries to reap the benefits of the biofuels trade, and for certification schemes to take account of the real environmental and social conditions in such countries. Environmental benefits could be lost if the sector’s expansion leads to further deforestation, and development benefits could also be lost if the choice of crop leads to competition for water resources or for land used to grow food crops. Certification schemes need to label biofuels according to environmental and social conditions prevailing in the producing countries, and must not undermine small-scale producers. [P][E][T][X]
US wind power resources The wind resource off the US mid-Atlantic coast could supply an average output of 330 gigawatts according to a study by researchers at the University of Delaware and Stanford University. This would be sufficient to cover all the energy needs of nine states from Massachusetts to North Carolina, plus the District of Columbia, with a 50 percent margin for growth in demand. The estimate is based on the installation of 166,720 wind turbines, each generating up to 5 megawatts of power, located at varying distances from shore, out to 100 metres of water depth, with "exclusion zones" for bird flyways, shipping lanes and other uses. Wind power generation in the US grew by 27 percent in 2006, adding 2.5 gigawatts capacity at a cost of $4 billion. Similar growth is expected in 2007. [P][E]
Off-shore wind-gas hybrid The UK government has given the go-ahead for a unique hybrid project that will generate electricity from wind and gas. The gas will maintain continuity of electricity supply when there is little wind. The field will have an installed wind power capacity of 108 MW from 30 wind turbines, plus 93 MW of backup gas fired generation. This will use gas from nearby fields in Morecambe Bay to produce power on small platforms out at sea. [P][E]
Current state of nuclear reprocessing Reprocessing of nuclear fuel can substantially reduce the problem of disposing of highly radioactive waste. The reprocessing at La Hague In France gives about a factor of 10 reduction in the mass of highly radioactive waste needing to be stored under the most stringent conditions. The record of La Hague also shows that the safety of reprocessing is no longer a problem. France reprocesses well over 1000 metric tons of spent fuel every year without incident at La Hague. The risk that reprocessing might fuel nuclear proliferation may also be solvable by using a new reprocessing scheme, called Urex+, developed at Argonne National Laboratory. The plutonium recovered from reprocessing can be blended with depleted uranium to create so-called mixed-oxide, or MOX, fuel, that can be reused in reactors. However, this still leaves a big disposal problem because spent MOX fuel rods contain a much higher concentration of plutonium and other long-lived waste. Fast breeder reactors could ultimately provide the answer, but only if fast breeder technology can be made sufficiently reliable. [P][D][E][T][U][W] |
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| [M] Materials, structures and surfaces | |
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Waste disposal materials Integrating radioactive material into mineral-based ceramics is a leading contender for the disposal of nuclear waste. Some of these ceramics, such as "zircon" (ZrSiO4), occur naturally with slowly-decaying radioactive isotopes incorporated into their crystalline structure and have remained intact over billions of years. However, physicists at Cambridge University have now found using a high-resolution nuclear magnetic resonance (NMR) technique that alpha-radiation causes too much damage in zircon to ensure safe nuclear disposal over long timescales. Plutonium would erode zircon in as little as 1,400 years. The NMR technique works by measuring the number of atoms dislodged on average in a sample every time it is struck by an alpha particle. It should help in finding other more durable ceramics by providing a deeper, atomic-scale understanding of damage events and a more precise estimates of the life span of other possible storage materials such as pyrochlore, the current best candidate. [M][D][P]
Record stiffness A material that is stiffer than diamond has been created by mixing particles of the mineral barium titanate and molten tin. Diamond was previously the stiffest material known. [M]
Enhancing stiffness Experiments at the University of Wisconsin have shown that a 50-year-old notion that composite materials must be made only of "stable" individual materials to be stable overall is incorrect. Mathematical formulas that predict how a composite will perform based on its component material properties suggest, counterintuitively, that employing an "unstable" material with a suitably chosen negative stiffness could in theory yield an infinitely stiff composite. The ability to enhance stiffness by incorporating a negative stability material has been verified in dynamic loading experiments. It is not yet certain whether the similar enhancements in stiffness can be obtained for static loading. [M]
Stretchy strong composites Spider silk is both stretchy and strong thanks to the fact that it is filled with many tiny crystals that are oriented towards, and strongly adhere to, the stretchy protein that forms their surrounding polymeric matrix. These crystals reinforce the structure of the material on the nanoscale. Engineers at MIT have copied this to make a stretchy and strong nanocomposite by incorporating a mixture of stiff clay particles throughout a rubbery polyurethane elastomer. The clay platelets were distributed randomly in the material so that it was reinforced in all directions and distorted very little, even when heated to more than 150 degrees C. The researchers say that molecular composites could be suitable for new lightweight membranes and gas barriers for fuel cells. The composites might also be useful in textiles, including tear-resistant films or components for body armour, and the technique might be used to make biocompatible polymers for use in biomedical devices. [M][D][H][N][P][S]
Fuel cell catalyst Platinum is the most efficient electrocatalyst for accelerating chemical reactions in fuel cells for electric vehicles. Unfortunately, however, reactions during the stop-and-go driving of an electric car cause the platinum to dissolve. This reduces its efficiency as a catalyst and has been a major impediment for using fuel cells in vehicles. Scientists at Brookhaven National Laboratory say they have now overcome this problem by adding gold clusters to the platinum electrocatalyst. Another advance has been found by researchers at Lawrence Berkeley and Argonne National Laboratories. They have identified a new variation of a familiar platinum-nickel alloy that is far and away the most active oxygen-reducing catalyst ever reported. [M][P]
Self-cleaning plastic Research at the University of Twente has shown that self-cleaning surfaces can be created by using a femtosecond laser to produce a surface structure with numerous tiny pillars. Water drops are lifted by these pillars, forming into spheres that roll off taking any particles with them. The structure mimics the self-cleaning surface of the Lotus leaf. The laser creates a mould that can then be used to cheaply imprint the structure into plastic. [M][O] |
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| [E] Environment, transport and marine | |
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IPCC report on climate change The 2007 report by the Intergovernmental Panel on Climate Change has concluded there is 90 percent certainty that the burning of fossil fuels and other human activities are driving climate change. Temperature rises by 2100 could range from 1.1 to 6.4 degrees C, with 4 degrees C being the most likely rise if the world continues to burn fossil-fuels at the current rate. The report was written by hundreds of experts and reviewed by hundreds more, from 113 countries. It is being released in stages during 2007. The first chapter, released in February, deals with the scientific basis for climate change. Part 2, to be released in April, deals with the impacts of climate change and vulnerabilities. Part 3, to be released in May, deals with how to mitigate the impacts. Despite past scepticism by the US administration, the White House has backed the report. [E][D][P][X]
Climate agreement A meeting in Washington of global political leaders has reached a new agreement on tackling climate change. The meeting brought together legislators from countries including the Group of Eight rich nations plus Brazil, China, India, Mexico and South Africa. They agreed that developing countries will have to face targets for cutting greenhouse gas emissions as well as rich countries and that a global market should be formed to cap and trade carbon dioxide emissions, with an agree limit of between 450 and 550 parts per million for the maximum rise in carbon dioxide levels. Developed countries must lead on emission cuts, with the targets for developing countries recognising their need for economic growth. The global carbon market will unite the European emissions trading scheme with other schemes emerging across the globe. Though the declaration is non-binding, it is seen as indicating a real change of mood on a replacement for the Kyoto Protocol. [E][D][P][X]
Green religion Religious movements could become a major influence in tackling climate change. Christian, Jewish and Moslem religious leaders across the world are emphasising that mankind has "stewardship" of the Earth and has a duty to protect the planet for future generations. This teaching is common to most of the world's major religions. [E][D][P][X]
Carbon-offset regulation To prevent carbon-offset scams, the UK government has launched a new set of standards for carbon-offset schemes based on buying in a regulated market that is overseen by the UN. At present most carbon credits are bought through unregulated markets. One concern about the unregulated sector is that people may be paying for projects to make emissions cuts that would have happened anyway. UN-regulated credits cost about £17 per tonne compared with roughly £8 ($16) per tonne on an unregulated market. The UK government is naming approved offset providers that meet its new standards. [E][P]
Carbon emissions from travel In the UK, the climate impact of each individual's annual travel is, on average, equivalent to 5.25 tonnes of carbon dioxide, according a study at Oxford University. People earning over £40,000 a year have an average impact of 11.3 tonnes of carbon dioxide a year - twice the UK national average. The study, based on a survey of almost 500 people in Oxfordshire, found that air travel accounted for 70 percent of personal travel carbon emissions. Individuals classified as being in the top tenth of emitters, were responsible for producing 19.2 tonnes of carbon dioxide per year from their flying alone. The study also found that for each mode of travel it is a minority of users, travelling comparatively long distances, who account for the differences between high and low quintiles, and hence it is particularly important to address long-distance travel by car and air. [E][A][P]
Global warming in China Chinese scientists have warned that rising temperatures on the Qinghai-Tibet plateau will melt glaciers, dry up major Chinese rivers and trigger more droughts, sandstorms and desertification. Temperatures across China were an average 1.4 degrees C warmer than usual in January this year, while the temperature on the plateau was 2.7 degrees higher. Average temperatures on the plateau have risen 0.42 degrees C each decade since the 1980s. [E][D][X]
Environmental action in China The Chinese government is preparing to adopt its first programme to cut its greenhouse gas emissions and will seek to reduce carbon dioxide emissions by 10 percent over the next five years, according to a senior official. So far, China has failed to make any progress in protecting the environment, despite government pledges to put the issue at the top of its agenda. The official China Modernisation Report 2007 says that China ranks 100 out of 118 countries in terms of environmental protection – the same level as in 2004. [E][D][P][X]
Vegetation and climate Using the Tropospheric Emission Spectrometer on board NASA's Aura satellite, scientists have been able to track the origin and movements of water vapour throughout the atmosphere. They were able to deduce the sources and processes that cycle water by analysing the distribution of the heavy water and light water molecules. This showed that tropical rainfall evaporation and water "exhaled" by forests are key sources of moisture to the tropical atmosphere, and that much more water than expected is transported into the lower troposphere over land than over oceans, especially over the Amazon River basin and in tropical Africa. The strength and location of such evaporation gives scientists new insights on how water in the atmosphere helps move energy from the Earth's surface into the upper atmosphere so that it is radiated back into space. The links identified between vegetation, hydrology and climate have implications for the effective management of ecological resources, and the work provides a baseline against which future changes in vegetation and climate interactions can be measured. [E][R]
Rising sea levels Satellite data shows that sea levels rose by an average of 3.3 millimetres per year between 1993 and 2006. This is substantially faster than was predicted in the 2001 IPCC report, which projected a best-estimate rise of less than 2 mm per year. The report quotes six models with central projections of sea level rises this century of between 28 and 43 cm. Sea levels rose by 17 cm (6.7 inches) in the 20th century. [E][D][R][P]
Glacial melting and sea level rise In estimating future sea level rises, the IPCC report has disregarded the surprisingly high discharges of ice from Greenland’s glaciers since 2000. This was done because the understanding of these melting processes is limited and there is no consensus on their magnitude. It is not certain that the rate of glacial melting will necessarily follow a steady upward trajectory. Two of Greenland's largest glaciers shrank dramatically and dumped twice as much ice into the sea during a period of less than a year between 2004 and 2005, but have returned to near their previous rates of discharge in 2006.The IPCC report noted that sea levels could rise faster than it is currently predicting. Some researchers think they will rise by at least 50 cm this century and could rise by up to 1.4 metres. [E][D][P]
Vehicle pollution, rain and wind power Particles from car exhausts generate more persistent and longer-lasting clouds but paradoxically less rain, according to new research. Putting more of these particles into the atmosphere also reduces the low-level winds, which could reduce the amount of wind power available in very polluted regions. [E][P] |
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| [R] Remote sensing and sensor systems | |
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Hot Jupiters The Hubble Space Telescope has allowed astronomers to study for the first time the layer-cake structure of the atmosphere of a planet orbiting another star. The planet is a so-called "hot Jupiter", a gas giant orbiting very close to its parent star. Hubble observed a dense upper layer of hot hydrogen gas where the super-hot planet’s atmosphere is bleeding off into space. About 10 to 15 percent of the more than 200 known extrasolar planets are hot Jupiters. [R][A]
Microshutter technology NASA has announced a new telescope technology called "microshutters" to be used in the James Webb Space Telescope (JWST). The microshutters are microscopic doorways that will mask unwanted light from foreground objects so that the telescope can focus on the faint light of the first stars and galaxies that formed in the universe. The JWST is intended to be a significant improvement on the aging Hubble Space Telescope. Its primary scientific mission is to search for light from the first stars and galaxies, to study the formation and evolution of galaxies, to understand the formation of stars and planetary systems, and to study planetary systems and the origins of life. The combination of redshift, dust obscuration, and the temperatures of many of the sources to be studied means that the JWST must operate in the infrared, spanning the wavelength range from 0.6 to 28 microns. The microshutter technology is expected to have many other applications outside astronomy, including in biotechnology, medicine and communications. [R][A][J][O][S]
Detecting extraterrestrial radio signatures Broadcasting, radar and communications are continually radiating rf energy from Earth into space. Astronomers have proposed that a radio astronomy facility, such as the Mileura Wide-Field Array Low Frequency Demonstrator (MWA-LFD), could detect similar rf emissions from intelligent extraterrestrial life on other planets. They calculate that by staring at the sky for a month, the MWA-LFD could detect Earth-like rf emissions from a distance of up to 30 light-years, which would encompass approximately 1,000 stars. Future observatories like the Square Kilometre Array could detect Earth-like rf emissions from 100 million stars. [R][A]
GIOVE-A In January 2006, GIOVE-A began transmitting Galileo navigation signals. This satellite is the first flight element in ESA’s in-orbit validation programme for Galileo. The GIOVE-A navigation signal has been broadcast continuously over the past year in order to: verify the critical technologies for the Galileo satellites, including the on-board atomic clock, navigation signal generator and navigation payload; to characterise novel features of the Galileo signal design, including the verification of user receivers and their resistance to interference and multi-path reception in realistic static and dynamic conditions; to characterise the radiation environment in Medium Earth Orbit (23 260 km altitude) planned for the Galileo constellation, to better understand this particular environment – particularly the radiation doses and electro-magnetic fields that could affect the design of the operational system. [R][A] |
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| [S] Sensor devices | |
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Detecting fake drugs Hand-held devices capable of spotting packaged fake drugs could be available by the end of 2007. Fake drugs are a huge problem in some parts of south-east Asia and Africa where they account for half of all medicines on sale. Hundreds of people have died after taking contaminated fakes and other people have been duped into buying medicines with no active ingredients. [S][H]
Directional underwater sensor Using optical fibres, researchers at Georgia Tech have created a sensor that detects the direction from which a sound is coming under water. The sensor copies how fish hear under water. Inside a fish’s ear, there are thousands of tiny hairs that move when a sound wave passes through the fish. The sensor is designed with two small plates attached by a hinge. One plate is held rigidly, and the other plate, which is made of a composite material with the same density as water, is free to move. The freely moving plate shifts in the sound field and follows the motion of water. A light signal sent through an optical fibre glued to both plates is modified by the motion of the freely moving plate. The researchers say that the technology allows the length of towed arrays of hydrophones to be reduced by a factor of five. [S][E][O][R]
Coherent computer-aided microscopy Researchers have found a practical way to extract clear images from the parts of a sample illuminated by light above and below the focal plane. The new method uses laser light to scan down through several millimetres of tissue at once. Computer analysis of the interference pattern constructs a clear 3-D image of the whole region. The aim is to do an optical biopsy through a needle or a catheter, allowing doctors to diagnose tumours without removing a piece of tissue from a patient. [S][H][O]
Ptychographic microscope A new type of "lensless" x-ray microscope has been developed at the University of Sheffield that can take pictures of biological samples in their natural environment. In existing lensless x-ray microscopes, data from just a single diffraction measurement are taken and must then be subjected to an algorithm that gradually hones in on a "solution" or image after many thousands of steps. The new microscope uses a technique called "ptychography" that melds many overlapping diffraction patterns. The researchers say this provides virtually instantaneous images with a wide field of view and a resolution limited only by the x-rays' wavelength. They believe that a large-scale version could be used to take 3D images like modern CT scans in hospitals. They also suggest that the lensless design principle could be extended to other parts of the spectrum that cannot be focused optically, such as ultraviolet or terahertz wavelengths. [S][G][H][N][R]
Nanowire sensor Yale researchers report they have built an exquisitely sensitive biological detector from silicon using conventional processing tools so that the sensor could in principle be mass-produced. The nanosensor uses slender nanowires wet etched into a bulk silicon wafer. These nanowires are coated in antibodies or other biological molecules capable of plucking their matching proteins from a solution washed over the sensor. The electric charges on the amassed proteins reduce the current flowing through the wires. The sensitivity of the device compares favourably with other nanowire sensors. [S][G][H][J][N]
Nanocantilever attogram sensor Physicists at Caltech have made the first "nanocantilever" that can measure extremely small masses under everyday conditions - unlike previous devices that needed a high vacuum or cryogenic temperatures to work. The new cantilevers can measure masses on the attogram scale with a resolution of just 100 zeptograms. The next aim is to create an array of hundreds of individual cantilevers, each of which is tailored to detect specific chemical species - a sort of electromechanical equivalent of a dog's nose. [S][J][N]
Compact neutrino detector Neutrinos are elusive particles that rarely interact with other matter. They are normally only glimpsed in huge detectors. However, low energy neutrinos probe entire nuclei at once, and scattering of low energy neutrinos is strong enough that detectors can potentially be quite compact. The problem has been that the detector needs to be acutely sensitive at low energies. US researchers have now made a new p-type germanium detector that should be good enough. An important application would be to monitor the neutrino signatures of nuclear reactors to detect any illegitimate tampering. Scientifically, the detector might conceivably provide the first concrete evidence for the much-debated fourth type of neutrino: the so-called "sterile" neutrino. [S][D][F][J][P] |
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| [O] Optoelectronics, optics and lasers | |
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Origami lens A "fold up" telephoto lens that sends light on a zigzagging path to its centre has been demonstrated by researchers in the US. The lens could fit inside ultra-thin camera-phones and other devices, providing higher quality images within a more compact package. The lens performs the same job as one seven times thicker by reflecting light along a path that "folds" back upon itself, from the edge of the lens to its core. [O][R][S]
Superlens microscope Superlens technology has potential for optically imaging manmade or biological structures that are too fine to be seen with a conventional microscope. Conventional lenses can only see details down to about half the wavelength of light. This limit is due to interference and diffraction that occurs as light bounces off an object. A superlens gets around this limit by collecting light waves that only occur very close to an illuminated object. These "evanescent waves" contain information at finer resolution but are hard to use because they exist only very close to the object, in what is called the "near-field". The first practical superlens, made of a very thin layer of silver, was developed in 2005 by researchers at Berkeley. However, it could only transmit the image to a sensor positioned within its own near-field. Now the researchers have improved it by adding 35 nm-wide corrugations to the silver surface. These diffract light from an object's near field so it can be viewed at much longer distance using a normal optical microscope. [O][S]
Magnetic reflection Light is an electromagnetic wave with an oscillating electric and magnetic field at right angles to each other. When light is reflected, its electric field vector is reversed in direction and the magnetic field is unchanged. Researchers at the University of Southampton have now devised a new type of mirror that reverses the light's magnetic field instead of the electric field. The mirror has three layers: a layer of aluminium, a layer of silicon dioxide, and a layer with a fish-scale like pattern of aluminium nanowires with about four scales per square micron. These scales interact with the light to produce the magnetic field reversal. The researchers say that the technology would be useful for photodetectors and for detecting tiny particles or molecules near the mirror’s surface. It could work in the near infrared as well as for visible light. [O][N][S]
Optical coaxial cable Physicists in the US have created the first nanoscale coaxial cables for transmitting light. The cable uses a carbon nanotube as its central conductor. The nanotube is surrounded by a concentric ring of transparent aluminium oxide providing the dielectric layer, and an outer concentric metal conductor. The separation between the inner and outer conductors is about 100 nm. The central conductor protrudes and acts like an “antenna”, gathering light and sending it down the cable. The researchers say the ability to control light over sub-wavelength distances could lead to better optical microscopes, smaller computer chips and more efficient solar panels. [O][C][J][N][P][S]
Light-matter-light information processing Physicists at Harvard have demonstrated an entirely new way to delay and manipulate optical information. They stopped and extinguished a light pulse in a Bose-Einstein condensate of supercooled sodium atoms, converting the information in the light pulse into a matter wave. The matter wave propagated until it reached a cloud of sodium atoms in which the information it carried was transferred to a laser beam. This regenerated the original light pulse but in the new physical location. Atoms in matter waves exist in slightly different energy levels and states than atoms in the clouds they move through. These energy states match the shape and phase of the original light pulse. Matter, unlike light, can easily be manipulated, and the experiments offer a powerful new means to control optical information for fibre-optic communication and quantum information processing. [O][C][I]
Slow light buffering of images Recent research into using slow light to buffer information has been concerned with delaying simple digital signals.. Researchers at the University of Rochester have now demonstrated that entire images with hundred of pixels can also be buffered, and it should be feasible to buffer very large amount of information. The buffering preserves the phase information in the image and photonic entanglement should also remain intact, making the approach promising for quantum information processing. The researchers have so far been able to delay light pulses containing the image by 100 nanoseconds and to compress them to 1 percent of their original length. They are aiming to increase this to several milliseconds and to delay terahertz bandwidth pulses by well over 1,000 pulse lengths. [O][C][I][R]
Circuit quantum electrodynamics Using artificial atoms on a chip, Yale physicists have created an electronic circuit that stores and measures individual microwave photons. This brings quantum mechanics to a larger scale and will hopefully be useful for building quantum machines. Single microwave photons can be used as mobile carriers of quantum information allowing distant qubits in a quantum computer to communicate directly. [O][C][I][J]
Frequency brush When a mode locked laser is made to produce a train of femtosecond pulses, the result in the frequency domain is a series of frequency spikes called a "frequency comb". A frequency comb allows a direct link from radio frequency standards to optical frequencies. This is key to making optical clocks. Researchers at NIST have now made two dimensional combs, more like brushes. They spatially separated the light twice, first vertically using a glass plate, and then horizontally with a metal grating. In combination, the two devices directed each frequency spike in a specific and unique direction to form a 2-dimensional array. The grid-like output was recorded by a digital camera connected to a computer, making it possible to measure and manipulate optical frequencies in a massively parallel manner. This could enable more precise control of individual frequencies than is currently possible in high-bandwidth communications, and thereby enable more channels to be packed into the same spectrum. The technique may also be useful in optical signal processing. [O][C][I][R]
Optical chaos The output of a semiconductor laser is normally regular, but by building two paired lasers very close to each other on a chip in such a way that each affects the operation of the other, researchers at the Technische Universiteit Eindhoven made their output chaotic. Chip-based chaos could be used for encryption, tomography, and possibly for establishing multi-tiered logic protocols exploiting the broadband output of the chaotic laser system. [O][C][I][J][R][S] |
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| [I] IT, communications, networking and secure systems | |
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Growth in mobile comms The market for content and services on cell phones is expected to grow to $150 billion by 2011, as access to the Web while on the move becomes easier and faster, according to research by Informa Telecoms & Media. Informa predicts that messaging services comprising SMS, multimedia messaging and instant messaging on cell phones will generate revenues worth $93 billion globally by 2011, up from $60 billion last year and an expected $67.4 billion in 2007. Entertainment services comprising games, music, TV, adult content and gambling will grow to $38 billion by 2011 from around $18.8 billion in 2006. [I][C][K][T][V]
Smart cellular radio In a decade or so, all cellphone handsets may well be based on software-defined radio. This will reduced power consumption substantially and make cellphones more versatile, able to easily switch among multiple wireless protocols or move to different frequencies, waveforms or applications. Software-defined radio will also make it technically straightforward to move to cognitive radio. Such radios will figure out which bands are underused and rendezvous with one another dynamically on available frequencies. The IEEE 802.22 standards group expects to complete the first standard for commercial cognitive radio by 2008, howbeit as a limited standard targeted at a specific spectral band rather than all-encompassing. However, in an urban environment, making cognitive radio work is a big and possibly insuperable challenge. The problem is that different cellphones or terminals may not be able to see each other and synchronise sufficiently reliably because of buildings in the way. [I][C][K][T][V]
Recycled satellite radio Television broadcasting satellites only have a life of 10-15 years because they run out of fuel and start to drift from their geosynchronous position. This means they are of no use to television services which require geostationary spacecraft for fixed satellite dishes to point at. ESA researchers are proposing that these old satellites could be reused to provide an in car satellite radio service. Their prototype system offers high-quality radio, video and data. It tracks the satellite positions and provides updated data to each car so that a small mobile antenna built into the bodywork can always point in the right direction to pick up a signal. [I][A][K][R]
Changing cyber threat Cyber criminals will increasingly turn their attention to the web and away from e-mail security in 2007, according to a report from Sophos. The number of websites infected with malware seems to be rising at an average of 5,000 URLs a day. The internet now represents the easiest way for cyber criminals to gain entry to corporate networks, as more users are accessing unregulated sites, downloading applications and streaming audio/video. According to the report, 30 percent of all malware is now written in China. Sophos detected 41,536 new pieces of malware in 2006. Of these threats, Trojans now outnumber Windows viruses and worms by four to one. Infected emails have fallen significantly from one in 44 during 2005 to just one in 337 during 2006. [I]
Threat from botnets At the World Economic Forum in Davos, IT leaders discussed the risk that criminals controlling millions of personal computers are threatening the internet's future. It is estimated that up to a quarter of computers on the net may be used by cyber criminals in so-called botnets. It is still too easy for net criminals to hide their tracks, and the fight against botnets needs all parties - regulators, governments, telecoms firms, computer users and hardware and software makers - to work together. Pirated Windows software is widely used and about half of this pirated software comes with Trojans pre-installed. Pirated versions of Windows Vista are already circulating in China, which could soon have the world's largest number of internet users, overtaking the US. [I]
Web 2.0 security Web 2.0 applications are growing in their importance to business, government and other organisations. But, by increasing the dissemination of information through collaborative tools and ‘social computing’, they are creating new security threats. The first wave of Web 2.0 applications has crept into organisations as users have installed instant messaging clients or downloaded voice over internet protocol (VoIP) products. Both are growing in importance to daily business operations, but the technologies remain largely unregulated. Many of the lightweight, consumer-friendly VoIP packages have no in-built security, a weakness already exploited by so-called ‘vishing’ attacks – the voice equivalent of phishing. Worms that penetrate VoIP could become a serious threat to the whole phone system. [I][K][T]
Controlling worms A computer worm is a self-replicating computer program. It uses a network to send copies of itself to other terminals on the network and, unlike a virus, it does not need to attach itself to an existing program. Many current security technologies for blocking worms focus on signature or pattern identification, but it can take several minutes from a signature-based system first recognizing that a packet or datagram is a worm to when it creates a new signature to block further spread. This delay gives the worm plenty of time to spread. Researchers at Penn State say they have developed a new technology for containing worms quickly. Called Proactive Worm Containment (PWC), this identifies a worm from the rate and diversity of connection requests it sends out to other network nodes, and can quarantine the worm within milliseconds. It then checks whether the code is malicious or benign, and if benign it lifts the quarantine. [I] |
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| [K] Knowledge, information and technology management | |
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Keystroke recognition Internet users have characteristic patterns of how they time their keystrokes, browse Web sites, and write messages for posting on online bulletin boards. Scientists are learning to use these typeprints, clickprints, and writeprints, respectively, as digital forms of fingerprints. The aim is to strengthen password security, reduce online fraud, identify online pornographers, and catch terrorists. But the technology might also make it impossible for a person to use the Web anonymously. [K][D][I][T]
Wikipedia-wise computer Using Wikipedia, Technion researchers have developed a way to give computers knowledge of the world to help them “think smarter,” making common sense and broad-based connections between topics just as the human mind does. Technion says that the new method will help computers filter e-mail spam, perform Web searches and even conduct intelligence gathering at more sophisticated levels than current programs. [K][C] |
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| [C] Computing, supercomputing, modelling and simulation | |
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Global Grid-based science Between 1 October 2006 and 31 January 2007, the WISDOM (World-wide In Silico Docking On Malaria) project has analysed on average 80,000 compounds an hour using the Enabling Grids for E-sciencE (EGEE) infrastructure. The compounds were screened using in silico docking techniques, whereby researchers computed the probability that potential drugs would 'dock' or interact with a target protein of the malaria parasite. A total of 140 million docking arrangements between drug compounds and target proteins were processed. Over the 10 weeks of screening, the project used the equivalent of 420 years of a single computer's computing power. Up to 5,000 computers were used simultaneously in 27 countries, generating two terabytes of useful data. [C][G][H][I][K]
80 core chip Intel has unveiled a chip with 80 processing cores that is capable of more than a trillion calculations per second (teraflops). The Teraflops chip is not a commercial release but could point the way to more powerful and highly parallel processors that will bring a revolution in software, programming, architecture and system design. The chip has a tile design in which smaller cores are replicated as "tiles," making it easier to design a chip with many cores. It has a mesh-like "network-on-a-chip" architecture allowing super high bandwidth communications between the cores, capable of moving terabits of data per second inside the chip. Intel has investigated methods to power cores on and off independently, so only the ones needed to complete a task are used, providing more energy efficiency. Further research will focus on the addition of 3-D stacked memory to the chip as well as developing more sophisticated research prototypes with many general-purpose cores. [C][J][W]
One-way quantum computer It is generally supposed that in quantum computing you start the machine off and keep it away from all external disturbances in order not to upset the quantum coherence. However, European researchers have developed a 'one-way quantum computer', in which the very act of observing the qubits drives the calculation. In the experiment, the researchers created an entangled state in which many qubits were connected to one another. Observing one qubit changed the others. The researchers showed that doing this successively in the right way drove the computer to complete the calculation in record time. [C][I] |
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| [W] Whole life engineering, manufacture and testing | |
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Systems engineering and project prediction MIT researchers, aerospace companies and INCOSE have together developed and validated a set of 13 measures that engineers can use to predict in advance how well a system or project will perform. One indicator is the risk handling trends. This indicates whether a project team is proactively handling potential problems (or risks) at the appropriate times in order to minimise or eliminate their occurrence. The other 12 leading indicators are: system definition change; backlog trends; interface trends; requirements validation trends; requirements verification trends; work product approval trends; review action closure trends; risk exposure trends; technology maturity trends; technical measurement trends; systems engineering staffing and skills trends; and process compliance trends. [W][X]
Living drug factories Scottish scientists have genetically engineered hens that can not only produce useful drugs in their eggs but also reliably pass on this characteristic to new generations of chickens. They now have five generations of drug-producing birds. If the amount of drug produced in each egg can be increased, chickens may become living drug factories. [W][G][H][T]
Urban design Accumulating evidence suggests that urban sprawl discourages physical activity and may thereby contribute to obesity and related health problems. Cities of low density, where people depend on cars to get to stores and other facilities, seem to favour obesity. In contrast, densely built urban areas may encourage pedestrian traffic and promote physical activity. [W][E][H][T][X] |
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| [X] Systems, complexity and risk | |
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Modelling the climate system The climate system consists of five elements: the atmosphere; the ocean; the biosphere; the cryosphere (ice and snow) and the geosphere (rock and soil). These components interact on many different scales in both space and time, causing the climate to have a large natural variability; and human influences such as greenhouse-gas emissions add further complexity. Predicting the climate at a certain time in the future depends on being able to include as many of the key processes as possible in climate models. At the heart of climate models and weather forecasts lie the Navier–Stokes equations, a set of differential equations that can describe the dynamics of the atmosphere as a continuous, compressible fluid. These equations have to be solved numerically, requiring huge computing resources and also ways to use parameterisation to deal with processes, and objects such as clouds, that are much smaller than the grid resolution of the model. Feedback mechanisms and forcing from phenomena such as volcanoes present another challenge. [X][A][C][D][E][T]
Biogeosociosystem modelling Though the IPCC report is focused on climate change it recognises that climate change is one symptom of global environment change, viewing the Earth as a coupled system of systems. Strong feedbacks exist between biogeochemical cycles and the climate system; for example, additional carbon released from the biosphere in a warmer climate will enhance climate change. Dynamic carbon cycling is now included in some of the models, and over the next few years biogeosociosystem models will take into account ever more complex details of dynamic land use change, of how natural carbon dioxide sources and sinks are changing in each area of the world, and how human society is reacting to the global warming threat. Predicting the scale of global warming depends critically on how different human groups act and respond. [X][D][E][P]
Synergistic threats The simultaneous effect of habitat fragmentation, overexploitation, and climate warming could accelerate the decline of populations and substantially increase their risk of extinction, according to research at Dalhousie University. Using experimental microcosm populations of rotifers (a type of zooplankton), the study found that individually each threat caused significant population declines, but that the speed of the declines was much increased when populations were exposed to more than one threat. These results indicate that multiple interacting threats are capable of causing rapid population extinction. [X][E]
Bacteria accelerating evolution The fossil record indicates that single-celled life first appeared on Earth about 3.5 billion years ago. But the evolution of complex organisms is comparatively recent. The reason for this, according to a model developed at Rice University, is that the speed and complexity of evolution is increasing over time because of horizontal gene transfer (HGT) between bacteria. The power of HGT is evidenced by the speed with which bacteria develop drug immunity. HGT increases the rate of evolution by propagating favourable mutations across populations. For example, the development of the adaptive immune system in humans and other jointed vertebrates can be traced to an HGT insertion about 400 million years ago. [X][E][G] |
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| [V] Virtuality and human-machine interface | |
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E-newspapers As people depend more and more on the internet to get news in real time, printed newspapers may soon be obsolete. Several newspapers in Europe and Asia are experimenting with e-readers and are producing dedicated e-reader editions. These are based on a new generation of handheld electronic reading devices using electronic paper. [V][I][K]
Cognitive bottleneck The risk from talking on a phone whilst driving is that the human brain is not good at quickly multitasking. This seems surprising given the brain's complexity and the fact subconsciously it can do a vast number of things simultaneously. Neuroscientists have long thought that some central bottleneck must exist in the brain. Researchers at Vanderbilt University believe that, by examining dual-task interference and patterns of neural activity over time, they have now located the bottleneck. They rapidly sampled brain activity using fMRI while subjects were performing two demanding tasks. Evaluation of the data produced by this rapid sampling method allowed them to characterize the temporal pattern of activity in specific brain areas. The results revealed that the central bottleneck was caused by the inability of the lateral frontal and prefrontal cortex, and also the superior frontal cortex, to process the two tasks at once. Both areas have been shown in previous experiments to play a critical role in cognitive control. [V][B]
Reading future intention Using a new combination of fMRI and multivariate pattern recognition, researchers in Germany, Japan and the UK have shown it is possible to read from brain activity how a person is intending to act in the future. Their experiments confirmed that, as previously supposed, freely selected plans (as opposed to plans following external instruction) are stored in the middle regions of the prefrontal cortex, the brain region involved in orchestrating thoughts and actions in accordance with internal goals. The intentions are encoded in a whole spatial pattern of brain activity rather than in single neurons. Regions of the prefrontal cortex towards the front of the brain store the intention until it is executed, whereas regions further back take over once execution is started. [V][B] |
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| [B] Brain research and human science | |
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Split-second timing For measuring long time intervals the body uses internal clocks. But new research indicates that internal clocks are not involved in measuring split second timing in the brain, for example in handling millisecond scale timing in processing speech, judging the trajectory of a speeding ball, and playing and appreciating music. The timing instead seems to come from the speed with which the processing of the whole event propagates through brain networks that have been trained by past experience. [B][V]
The common mind Although no two brains are alike, they can display a comparable pattern of neural activity when exposed to similar sensory input. Likewise, two people can share the same thought, even though their brains are different. They have different circuits, but similar neuronal dynamics. Researchers at Max Planck have developed a mathematical method that can deduce the possible neural structures from the neuronal dynamics. The researchers hope that their method will assist getting closer to understanding which of the possible network configurations was adopted by evolution and why. [B][C][K][U][V]
Altruism Altruism, the tendency to help others without obvious benefit to oneself, appears to be a real behaviour and linked to an area of the brain called the posterior superior temporal sulcus, according to research at Duke University. [B]
Insula and addiction Recent research has shown that cigarette smokers who suffer brain damage to the insular cortex, from a stroke for instance, have their addiction to cigarettes practically eliminated and can quit smoking easily and immediately. The finding that one small brain region could be so key to smoking addiction is especially surprising, given the brain-wide effects of nicotine on the nervous system. The insula is linked to emotion and feelings, and to learned behaviours, and fMRI studies have implicated it in conscious desires, such as food craving and drug craving. It is therefore plausible that changes to the insula, perhaps by means of therapeutic drugs, might enable people to quit other addictive behaviours, including alcohol abuse, eating disorders and drug addictions. [B][H]
Thinking and schizophrenia The protein DARPP-32 is a master protein that plays a key role in the pathway that links the brain's executive area in the prefrontal cortex with the striatum. The striatum is the portal connecting to the more primitive areas of the brain that lie beneath the cerebral cortex. These include structures involved in emotion, motivation and emotional association with memory, and in registering and fusing stimuli from outside or inside the body. Information flow between the striatum and the prefrontal cortex allows conscious analysis and decisions, and the striatum may participate in decision-making processes by evaluating the degree of incentive provided by each of the possible options. NIH researchers have now shown that most people inherit a version of the DARPP-32 gene that enhances the strength of this cortex-striatum connectivity and thereby enhances conscious thinking and judgement. But this version of the gene also appears to increase the risk of schizophrenia. This may perhaps be because the strong information exchange can overload the prefrontal cortex. [B][G][H][V]
Possible breakthrough for Parkinson's Researchers at Stanford University School of Medicine report that combining a drug already used to treat Parkinson's disease with an experimental drug that slows the enzymatic breakdown of endocannabinoids in the brain triggered a dramatic improvement in mice with a condition similar to Parkinson's. Parkinson's disease is related to a shortage of dopamine in the part of the brain called the striatum. The researchers found that two different types of striatum cell appear to form two complementary circuits. One is thought to be involved in activating motion, while the other is thought to be involved in restraining unwanted movement. The researchers conjecture that dopamine modulates these two circuits in opposite ways. When dopamine is depleted, the pathway responsible for inhibiting movement becomes overly activated - leading to the difficulty of initiating motion. Endocannabinoids and dopamine appear to work in concert to keep this inhibitory pathway in check. [B][H]
Brain renewal It has long been known that the brains of adult mice and rats are capable of producing new neurons from stem cells. Scientists in New Zealand have now found firm evidence that a similar capacity exists in humans. It has also been shown, in the case of mice, by Canadian scientists that the newly generated brain cells are three times more active than the old ones. This adds to the evidence that the brain creates a steady supply of new cells to maintain its mental faculties throughout life. The hope is that a way may be found to boost production of new neurons and to use this to treat brain injuries and diseases such as Parkinson's. [B][H]
Origin of Alzheimer's disease In Alzheimer’s disease, two kinds of abnormal structures accumulate in the brain: amyloid plaques and neurofibrillary tangles. The plaques contain fibrils that are made from protein fragments called “beta-amyloid peptides.” The tangles also are fibrous, but they are made from a protein called “tau.” The puzzle has been how these two abnormalities are related. Researchers at the University of Virginia believe they have found the answer in the form of a highly toxic interaction between beta-amyloid and tau that occurs at an early stage before they form plaques and tangles. [B][H]
Origin of Alzheimer's disease The long-suspected link between Alzheimer’s disease and abnormalities in the way amyloid protein is processed in the brain has been confirmed by genetic research at the University of Toronto. From studying the DNA of 6861 people, 46 percent of whom had Alzheimer's, the researchers found that those with the disease were more likely to have variants of the gene SORL1. This gene usually produces a protein that binds the harmless protein amyloid and transports it to an area of the cell where it can be recycled. They showed in laboratory experiments that deactivating the SORL1 gene led to a substantial increase in the conversion of amyloid protein to toxic beta-amyloid. [B][G][H]
Inducing torpor In mammals, hibernation is so widespread that researchers reason that the ancestor of all mammals must have been a hibernator. This means that humans might still retain some latent capability for hibernation. Inducing a hibernation-like state of torpor in a wounded soldier or a bleeding-accident victim might give doctors precious extra time to stop and reverse the damage. Other patients would benefit if donated organs could be put in torpor storage for prolonged shelf lives. And for astronauts, torpor might facilitate travel to distant planets. Much is now known about the torpor in hibernating animals. It is a distinctive state, different from sleep, that shuts body functions down in ways that not only conserve energy but also prevent muscle atrophy and damage from ischemia. It is not clear what chemicals control hibernation, but some chemicals such as hydrogen sulphide can induce a torpor-like state and lower metabolism in non-hibernating mammals including humans. [B][A][G][H][T] |
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| [H] Healthcare and medicine | |
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Adjuvant-generating vaccine UK scientists are developing a new generation of vaccines targeted at tuberculosis, malaria and HIV. Vaccines for malaria have already worked in mice, and human trials should start within two years. What is particularly new is that the vaccines have built-in genes for making an adjuvant inside the cells they infect. Adjuvants are substances that alert the immune system and enhance its response to the vaccine. The vaccine is made using a harmless viruses that have been engineered to carry genes both for an antigen and for an adjuvant protein. An important issue may be how to control the level of adjuvant so that the immune system does not over or under-react. [H][G][M]
Anti-allergen vaccine Existing vaccines for allergies involve three to five years of regular injections with increasing amounts of allergen. This slowly changes the immune response from a predominance of T-helper 2 (TH2) cells to T-helper 1 (TH1) cells. TH2 cells trigger allergic reactions whereas TH1 cells stimulate the production of protective antibodies. The change is slow because the allergen is not being specifically directed to the right place in the immune cells. Now Swiss researchers report they have developed "modular antigen translocating molecules" (MAT), which make vaccines more efficient by delivering the antigens right to where they are needed within an immune cell. [H]
Oncolytic reovirus therapy Reoviruses (Respiratory Enteritic Orphan virus) are a family of viruses that are mostly harmless, though some can cause mild respiratory and gastrointestinal infections. Recently a harmless reovirus has been developed by a Canadian company into an oncolytic virus that attacks tumour cells. Evidence is mounting from laboratory experiments and clinical trials that this oncolytic reovirus not only directly kills cancer cells but can also train the patient's immune system to continue to destroy the tumour cells even after the reovirus itself is no longer present. There is also evidence that briefly suppressing the immune system can allow the virus to continue replicating longer, leading to increased cancer cell killing and enhancing the training of the immune system. The hope is that oncolytic reovirus therapy may enable the patient's immune system to sustain a powerful, long lasting and adaptive defence against the cancer. [H][G]
Metabolic factors in cancer Researchers at the University of Alberta have found that a drug called dichloroacetate (DCA) kills lung, breast and brain cancer cells, but not healthy cells. Tumours in rats deliberately infected with human cancer shrank drastically when they were fed DCA-laced water for several weeks. DCA attacks a unique feature of cancer cells: the fact that they make their energy by glycolysis throughout the main body of the cell, rather than in their mitochondria. DCA reactivates the mitochondria, and thereby restarts the process of cell suicide (apoptosis) that is controlled by the mitochondria. The findings emphasise that metabolic factors may play a key role in cancer. Cells in the middle of a benign tumour might switch to glycolysis when they cannot get enough oxygen for their mitochondria to work properly. This switch disables apoptosis and makes the cells immortal. Glycolysis also generates lactic acid, which can break down the collagen matrix holding cells together and thereby encourage metastasis. The findings might lead to a cancer treatment. DCA is cheap and has been used for years to treat rare metabolic disorders. [H]
Chronic inflammation and cancer There is plenty of evidence that chronic inflammation can promote cancer. US researchers have found a possible mechanism that could explain this. The researchers have found that the two pathways of inflammation and development are linked by a protein called p100. This protein provides cells with a long term memory of inflammatory exposure. Though the inflammatory response may be brief, the p100 remains raised for long enough to promote the much slower process of development. A little inflammation is necessary for the normal development of the immune system and other organ systems, but chronic inflammation produces too much p100 and this overstimulation can encourage the development of cancer. [H][G]
Silicon medicine As carbon-based life forms, humans and other animals are invariably treated for disease with the help of carbon-based medicines. However, researchers at the University of Wisconsin have found that the effectiveness and safety of an important anti-inflammatory and anti-cancer drug were enhanced remarkably by replacing one of the molecule's carbon atoms with a silicon atom. This raises the possibility that other drugs could be tweaked and improved in the same way, perhaps to remove side effects. [H]
Telomeres and heart disease Statins may be effective in preventing heart disease and strokes partly because they prevent or reduce the effect of telomere shortening, according to research at Leicester and Glasgow Universities. It is not known why shortened telomeres increase a person's risk of heart disease. One possibility is that degraded telomeres might impede the ability of cells from the bone marrow to repair damaged parts of the arterial walls. [H]
Xeno-transplantation from pigs to humans In people with type 1 diabetes, the islet cells of the pancreas do not produce enough insulin to regulate blood glucose effectively. Insulin injections are the standard treatment. An alternative is to transplant islet cells from a human donor. But, there is a shortage of donors, the procedure is very expensive and patients have to take immunosuppressant drugs for life. Another alternative is to transplant neonatal islet cells from pigs into human patients. This approach is about to begin clinical trials in Russia. The pigs are specially bred to be free from common viruses, bacteria and parasites in order to avoid the risk of transferring pig diseases into humans. The islet cells are coated in alginate, a derivative of seaweed, which allows glucose, insulin and oxygen to pass through, but blocks antibodies. As a result, patients should, in theory, not need to take any immunosuppressants. The procedure is estimated to be less than a tenth the cost of using human islet cells. [H]
Autoimmune disease NIH research has found the origin of the rogue B-cells that are involved in autoimmune diseases. B cells are formed in the bone marrow and produce antibodies that combat pathogens by binding to them and rendering them harmless. The antibodies are generated from the cutting and splicing of immunoglobulin genes early in B-cell development. This cutting and splicing can also inadvertently produce an antibody that is self-reactive, recognising a component of one’s own body rather than a pathogen. This lead to a rogue B-cell. The body has a built-in mechanism to deal with these errant cells, either by killing them or by correcting the error. The research has found, however, that this in about 10 percent of cases this correction still leaves the B-cell able to produce self-reactive antibodies that can produce autoimmune disease. [H][G] |
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| [G] Genomics, biotechnology and bioinformatics | |
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Switching HIV off Whilst there is no cure for lingering viral infections such as HIV and herpes, a recent study at Princeton University suggests it may be possible to deactivate such viruses indefinitely. The researchers have discovered a specific genetic trigger that makes HIV fall into its latent phase, where the virus essentially hibernates, relatively harmlessly, but awaiting an opportunity to re-emerge and wreak havoc. The reactivation involves a genetic circuit in HIV's DNA. This creates a chemical feedback loop between the virus and the infected T cell that produces increasing quantities of a protein called Tat that converts the T cell into an HIV factory. [G][H]
Pancreatic cancer stem cells Researchers at the University of Michigan have, for the first time, identified human pancreatic cancer stem cells. Their study demonstrates that the very small subset of cells in a human pancreatic tumor that cause the cancer to grow and propagate have stem cell-like features. The study also advances the emerging theory that stem cells may lie at the heart of some, if not all, cancers. That theory suggests that only cells that have can self-renew and differentiate into other types of cells are capable of producing tumors. These "cancer stem cells," could derive from normal adult stem cells in organs that have mutated, or from a differentiated cell that has devolved to take on "stemness". Cancer stem cells do not rapidly multiply and are therefore resistant to traditional chemo- and radiotherapy. Pancreatic cancer has the worst prognosis of any major cancer, and the hope is that if a therapy can be found that is effective against the cancer stem cells, this might provide an effective treatment.. [G][H] | ||