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Top Stories in Science
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May 2007 Issue |
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| [D] Defence and security |  |
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IPCC third report The Intergovernmental Panel on Climate Change (IPCC) has released the third of its four reports on global warming. This deals with ways of limiting greenhouse gas emissions. It estimates that it would cost no more than 3 percent of global GDP to stabilise greenhouse gas concentrations at below 535 ppm, enough to limit global warming to 2 degrees C. The report discusses key mitigation technologies and practices, and non-technological measures, such as lifestyle changes. It covers possible government action including international co-operation, regulation, tradable permits, taxation, financial incentives, and increasing relevant R&D. The report emphasises that delay will considerably increase costs and risks from 2030 onwards. [D][A][C][E][P][R][W][X]
Water security Water shortages now affect 450 million people worldwide. Even where there is water, it is often too contaminated to drink without risking serious illness. As much as a quarter of Bangladesh's population is drinking water containing 10 to 50 times the amount of arsenic that is considered safe. The combination of human need and the hope of eventual profit is spurring companies to develop a wide range of technologies that can help secure safe drinking water for the world's poor. Usually the projects are offshoots of technology that companies are developing for profit-generating business. Success depends not only on sufficiently cheap technology but also getting local buy-in and enterprise. [D][E][H][M][N][T][W][X]
Euro-African bird flu Detailed genetic studies of H5N1 bird flu samples collected in Europe, the Middle East and Africa (EMEA) have revealed the existence of a distinct EMEA strain that is different from the three other major H5N1 lineages in Asia. It has a mutation associated with virulence in mice and adaptation to mammalian hosts, and its spread has coincided with the rapid appearance of H5N1 cases in mammals including humans in Turkey, Egypt, Iraq and Djibouti, and cats in Germany, Austria and Iraq. Almost half of the cases in humans have proved fatal. The broad dispersal of the EMEA strain suggests that human movement, and not the migration of wild birds, is primarily responsible for its rapid spread. [D][G][H]
Pandemic response The US military has begun to plan for a possible avian flu pandemic that could kill as many as three million people in the United States in as little as six weeks, according to a Pentagon planning document. [D][H]
Rapidly manufacturing flu vaccine A new influenza vaccine produced by caterpillar cells has proved effective in preventing flu. The advance could revolutionise the manufacture of flu vaccine, now produced in chicken eggs in a long, cumbersome process prone to contamination and other failures. The new vaccine is produced by caterpillar cells infected with a genetically modified baculovirus. In its normal form, this virus prolifically produces a protein called polyhedron. The researchers replaced this with the gene for the influenza haemagglutinin. Lab-grown insect cells infected with the modified baculovirus then churned out large amounts of the haemagglutinin, which elicited flu-fighting antibodies when injected into people. With the new method, the appropriate haemagglutinin gene could be quickly inserted into baculovirus, speeding production of effective flu vaccines. [D][G][H][W]
Tamiflu production Roche reports that, together with its partners, it has increased production capacity for the anti-viral influenza drug Tamiflu to more than 400 million treatments a year. Supply now significantly exceeds current Tamiflu orders for stockpiling against a possible bird flu pandemic. According to the WHO, bird flu patients who receive early treatment with Tamiflu have the best chances of surviving. [D][G][H][W]
Non-lethal weapons According to the New Scientist, DARPA is developing a plasma shield that would allow troops to stun and disorientate enemies. The system will use a technology known as dynamic pulse detonation (DPD), which involves producing a ball of plasma with an intense laser pulse, and then a supersonic shockwave within the plasma using another pulse. This causes a bright flash and a loud bang. [D][O]
Friendly-fire incidents The House of Commons Public Accounts Committee has criticised the UK Ministry of Defence for failing to develop viable combat identification solutions to counter the risks of friendly-fire incidents. The committee found more than half of projects to improve safety had been deferred, delayed or "re-scoped" in the last four years. In reply, the MOD explained why combat identification is so complex and said that no single piece of technology will resolve all the issues. [D][A][I][R][S][T][X]
Airport defence The New Scientist reports that a recent study by the US Department of Homeland Security concluded that it would be too expensive to fit all airliners with lasers to blind heat-seeking missile sensors. It is now considering the use of high-altitude drones to patrol the skies within 105 km of airports. The unpiloted aircraft would monitor the area for missiles in flight, and then either tackle them directly or alert anti-missile weapons on the ground, the article says. [D][A] |
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| [A] Aeronautics and space | |
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Flapping-wing aircraft A NASA-funded project has developed concepts for planes that fly by flapping their wings, like birds. The plane would be unmanned, solar-powered, and made of strong, lightweight materials. Its size could range from a few metres across to perhaps a hundred metres, and it could remain airborne for long periods as a surveillance or communications platform. The researchers say that the greatest challenge is to develop a control scheme for the wings. These are made from ionic polymer-metal composite that is sandwiched between two metal electrical grids, each containing thousands or even tens of thousands of electrodes. The hope is that with a very fine grid it would be possible to emulate the delicate wing movements of flying vertebrates. Neural networks or some other kind of artificial intelligence would enable the plane to "learn" how to control itself in flight. [A][M][U]
Flying observatory The Stratospheric Observatory for Infrared Astronomy (SOFIA) has completed its first flight tests. SOFIA is a heavily modified 747 jumbo jet equipped with a 2.5-metre telescope weighing 20 tonnes. Flying 12 km above the ground, the observatory will be above more than 99 percent of the atmospheric water vapour. This will make it nearly as good as a space-based observatory for infrared astronomy. [A][R]
Autonomous in-orbit docking and servicing The Orbital Express mission has successfully performed the first in orbit autonomous separation and docking. The ASTRO (Autonomous Space Transport Robotic Operations) and NextSat satellites, which together make up the mission, were launched together. They then autonomously separated and ASTRO travelled 10 metres away from NextSat, waited for 90 minutes and then navigated back to NextSat and docked. The manoeuvre was performed with no contact from ground controllers: ASTRO relied on its own sensors and guidance system to keep track of NextSat. This is the first step toward Orbital Express’ eventual goal of separating to a distance of 7 km and remating. DARPA hopes this will pave the way for future robotic spacecraft that could come to the aid of ailing satellites or refuel them to extend their operational lives. Even in geosynchronous orbit, where many communications satellites reside, there are communications delays with Earth and occasional dropouts that would make it difficult for ground controllers to perform such precise operations. [A][I][R][U]
Noctilucent cloud A NASA spacecraft has been launched into a polar orbit to study iridescent, silvery blue clouds at the edge of space that may be connected to global warming. The shimmering clouds can be seen glowing just before sunrise or just after sunset. They are at an altitude of about 80 km and the Sun illuminates them from below the horizon. They were first observed above polar regions in 1885, but in recent years they have spread to latitudes as low as 40°, while also growing in number and getting brighter. [A][E]
Lunar static Once per orbit, the Moon moves through the Earth's magnetic tail - the region on the night side of the Earth where the magnetic field is drawn out into a long tail pointing away from the Sun. In the middle of the tail lies a sheet of plasma that charges up the lunar surface with static electricity. A new model predicts that the exposure of the Moon to this plasma charging varies markedly over an 18-year cycle linked to changes in the Moon's orbit. This exposure was fortuitously low at the time of the Apollo landings in the early 1970s, but will be at a maximum around 2020 when the US plans to send astronauts back to the Moon. The lunar static will increase the danger from lunar dust and electrical discharges. [A]
Potentially habitable exoplanet Using the ESO 3.6-m telescope, European astronomers have discovered the most Earth-like planet outside the Solar System found to date. It has a radius only 50 percent larger than the Earth's and should be at the right temperature for liquid water. It orbits a red dwarf star that is already known to harbour a Neptune-mass planet and may also have a third planet of about 8 Earth masses. [A][R]
Vast intergalactic plasma cloud Radio astronomers have discovered a giant cloud of intergalactic plasma that stretches more than 6 million light years across. The discovery raises many important questions. For example, what kind of mechanism could create a cloud of such enormous dimensions that does not coincide with any single galaxy, or galaxy cluster? Could the same mechanism may be connected to the mysterious source of ultra high energy intergalactic cosmic rays?. [A][R][F] |
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| [U] Unmanned vehicles and robotics | |
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Robotic heart surgery A robotic caterpillar has been developed by scientists at Carnegie Mellon that can crawl across the surface of the heart to deliver treatment. It could allow procedures to be carried out without having to stop the heart, reducing the risk of illness linked to heart bypass procedures. The tiny robot, just a few centimetres long, can move at up to 18 cm per minute, controlled by "push and pull" wires from outside the body. It is inserted below the ribcage by keyhole surgery and is attached to the heart via a vacuum line to two sucker-like feet with which it can crawl. Trials on pigs found it could fit pacemaker leads and inject dye into the animals' hearts. The researchers are now working on adding a radiofrequency probe to the device in order to treat arrhythmias by selectively killing malfunctioning heart tissue. They also plan to add a camera. [U][H]
Robot navigation People find it easy to create "mental maps" of their surroundings, but robots find this hard. Typically, they use laser scanners and odometers to measure distances, but building up a map from this data is very laborious. Researchers are exploring ways robots might use background knowledge, like humans do. One approach, developed at Purdue, identifies unexplored "frontier cells" adjacent to areas that have already been mapped and uses the cells' pattern of corners to search for similar patterns that have already been mapped. If a match is found, the algorithm uses the existing map to make a prediction of the contents of the frontier cell. If the prediction has a high confidence score, the cell can be left unexplored. [U][R]
Telepresence Robot Kit Carnegie Mellon University researchers are trying to make highly capable robots that are accessible and affordable for college and pre-college students, as well as anyone interested in robots. For this, they have developed a new series of robots that are simple enough that almost anyone can build them with off-the-shelf parts and can be wirelessly connect to the Internet so that they can be remotely controlled. [U][I][K][V]
Network self-organisation Topologists have developed a powerful arsenal of numerical and algebraic tools that enable them to extract important features from a shape whose precise geometry is unknown. These techniques are important for enabling sensor networks to self-organise. In the not too distant future, billions of smart sensors may be embedded into buildings, streets, fields, or even people. These devices might monitor weather, traffic, crop conditions, the progression of diseases, or a host of other variables. The sensors will self-organize into networks that adjust their structures and functions in response to the information that they pick up. Using topological mathematics, the network can piece together its global structure from local snapshots and be mapped without needing to know the precise location of each sensor. Calculating, for example, a topological function called the Rips complex can reveal which sensors in a network must be active to give full coverage of the area and which can be kept in reserve. Sensors can compute the network's homology by communicating with their neighbours, and networks can self-organise even if sensors are constantly moving. [U][C][E][H][I][K][R][S][T][X] |
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| [P] Propulsion and energy | |
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Linear transform driver The prospects for the inertial confinement approach to fusion power could be greatly enhanced by a new device called a linear transformer driver (LTD) that has been developed by Russian and US scientists. An LTD should be able to sustain each fusion reaction for much longer and also be fired as often as every 10 seconds. This could boost fusion power output to a useful level. The device fires an intense pulse of electricity – half a million amps and 100,000 volts. It has just completed preliminary testing at the Sandia Z Machine facility. LTDs achieve better performance partly because they are simpler than previously-used Marx generators, which need extensive wiring and hundreds of thousands of gallons of insulating water and oil. LTDs also do not generate magnetic fields that reduce performance. [P][O]
Sustainable biofuel A new UN report suggests biofuels could cause as many problems as they solve. Biofuel production tends to involve large-scale mono-cropping, which could lead to significant biodiversity loss, soil erosion and nutrient leaching, and could drive the world's poorest farmers off their land. The demand for water and land to grow bioenergy crops could put pressure on food crops and other uses. Conversion of land to produce biofuel crops would further threaten tropical forests. Uganda, for example, is proposing to cut down a quarter of its remaining forests to expand sugar cane production for biofuel feedstock. To tackle these issues a new multi-stakeholder, international alliance is to draw up global standards for sustainable biofuels production and processing. [P][D][E][X]
Bio-ethanol Currently, almost all industrial ethanol derives from either starch found in corn grain or from sugar cane, both food crops. To make bioethanol sustainable a way must be found to instead produce ethanol cost-efficiently from cellulose. Researchers at Purdue have found that pretreating corn plant tissue with hot water exposes minute pores of the plant's cell walls. These enlarged pores are more easily attacked by enzymes that convert cellulose into glucose, which can then be fermented into ethanol. Researchers at UCSD have used computer simulation to study how the enzymes work in order to speed them up. The simulation has revealed how the binding portion of the enzyme changes shape so that it can straddle the broken end of the cellulose chain. This gives the enzyme a crucial foothold to begin the process of digesting or "unzipping" the cellulose into sugar molecules. Researchers at Cornell have discovered a new class of plant enzyme to may work better. [P][C][E][G][M]
Quantum effects in photosynthesis Plants and some bacteria use photosynthesis to transform light, carbon dioxide and water into chemical energy. They do this remarkably efficiently. But attempts to copy this in artificial photosynthesis systems have been disappointing. Now a collaboration between three US teams has found that the plants and bacteria may achieve their high efficiency by exploiting quantum coherence. The teams studied bacteriochlorophyl (BChl), a protein from a photosynthetic bacterium. This protein wraps around three clusters of seven chlorophyll molecules and is involved in a complex photosynthesis system called the antenna system in which molecules efficiently transfer energy from light in a cascade. The researchers observed that when light-induced excitations in the complex meet, they interfere constructively creating long-lived wavelike electronic quantum coherence effects. This wavelike characteristic can explain the extremely efficient energy transfer because it enables the system to simultaneously sample all the potential energy pathways and choose the most efficient one. [P][E][N][O]
Efficient photosynthesis Protein dynamics controls the kinetics of initial electron transfer in photosynthesis, according to researchers at Arizona State University, and this allows the plant or bacteria to harness all of the light energy. The protein motion adjusts the electron energy until it is just right for the next stage of the photosynthesis process. The researchers propose that it may be possible to exploit this concept to improve the efficiency of organic solar cells by incorporating solvents that move on a variety of time scales, which could "tune" the molecules to work in a wider variety of conditions. [P][E][M][N][O]
Efficient plastic solar cells To be commercially viable, plastic solar cells need to be around 8 percent efficient. At present, the best plastic solar cells can achieve not more than 5 percent. They are made from a light-absorbing polymer containing soccer ball-shaped carbon molecules called fullerenes. The big problem is that space charge builds up in the plastic and opposes the photocurrent. US and Korean scientists have now shown that this problem can be overcome by carefully heating cells to around 150 degrees C. This makes the fullerene molecules form whiskers of crystal that also trigger crystallisation in the surrounding polymer. The fullerene-and-polymer crystal creates a network across the cell that dissipates any space charge. So far the scientists have achieved up to 7 percent efficiency and believe they can increase this to 10 percent. [P][J][M][N][O]
Thin film solar cells The efficiency of thin film silicon solar cells can be boosted to over 13 percent, according to researchers at the University of New South Wales. They have devised a way to deposit a thin film of silver, about 10 nm thick, onto a solar cell surface and then heat it to 200 degrees C. This breaks the film into tiny 100-nm "islands" of silver that greatly boost the cell’s ability to trap and absorb light, and hence the cell's efficiency. [P][J][N][O]
3-dimensional solar cells In conventional flat solar cells, the photovoltaic coatings must be thick enough to capture the photons, whose energy then liberates electrons from the photovoltaic materials to create electrical current. However, each mobile electron leaves behind a "hole" in the atomic matrix of the coating. The longer it takes electrons to exit the photovoltaic material, the more likely it is that they will recombine with a hole, reducing the electrical current. Researchers at Georgia Tech have made 3 dimensional photovoltaic coatings that use an array of carbon nanotube towers coated with cadmium telluride and cadmium sulphide, which serve as the p-type and n-type photovoltaic layers. This 3D structure captures nearly all the incident light. The improved absorption enables the coating to be made thinner, thereby reducing electron-hole recombination. Also, the array remains efficient even when it is not pointed at the sun, a particular advantage for use on satellites. [P][A][J][N][O]
Photocatalytic production of hydrogen Researchers at Washington University in St Louis have developed a unique photocatalytic cell that splits water to produce hydrogen and oxygen using sunlight and a nanostructured catalyst made of oxide semiconductors. The researchers have developed a process to make the catalyst, which they say can be scaled up to produce large structure in a very cost effective manner and at atmospheric pressure. [P][M][N][O]
Photoreducing carbon dioxide Researchers at UCSD have developed a prototype device that uses sunlight to split carbon dioxide into carbon monoxide (CO) and oxygen. It contains a semiconductor and two thin layers of catalysts. The semiconductor generates photoelectrons and the catalysts use these to convert the carbon dioxide into carbon monoxide on one side of the device and oxygen on the other side. CO is an important industrial material used to manufacture chemicals including detergents and plastics. It can also be converted into liquid fuel. The semiconductor in the prototype device is silicon and the energy of the photoelectrons has to be increased electrically to split the carbon dioxide. However, a wider bandgap semiconductor should be able to produce sufficiently energetic photoelectrons directly. [P][E][J][M][O]
Using carbon dioxide If carbon dioxide is captured for sequestering, it will also make sense to use it industrially as a feedstock. Chemicals already produced routinely from carbon dioxide include urea to make nitrogen fertilizers, salicylic acid as a pharmaceutical ingredient, and polycarbonate-based plastics. Carbon dioxide could be used more widely as an industrial solvent. It can be reduced to formic acid, which has potential to power fuel cells and automobiles and is a precursor for other fuels and commodity chemicals, including polymers. Carbon dioxide can be converted into carbon monoxide (CO), it can be used to make hydrocarbons, and it can be used with industrial waste streams to make polymers. [P][E][J][M][T][W] |
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| [M] Materials, structures and surfaces | |
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Biodegradable plastic Researchers in Massachusetts have made a starch-based plastic that can biodegrade in soil, ocean and wetlands, and can handle temperatures of up to 140 degrees C. It is made from polyhydroxyalkanoate produced by genetically modified bacteria. [M][E]
Replicating spider silk The toughness of spider silk comes not just from its strength but also from its superb ability to absorb energy. Spiders produce several different types of silk, each from a different specialist gland. Dragline silk is very strong; capture-spiral silk is sticky, extremely stretchy, and tough; aciniform silk, which the spider uses to wrap wriggling prey, is even tougher. The silk's mechanical properties primarily derive from the proteins that make up the material and the spinning process that produces the thread. The thread contains hundreds of thousands of protein chains, each of which folds on its own and also arranges itself among other chains in the fibre. The liquid "dope" from which the silk is spun behaves like melted polymers, both in spiders and in silkworms. Well-developed theories of polymers can be used in studies of silk dope. With rheology also proving to be a valuable tool in showing how silk is physically processed, scientists may be close to being able to replicate spider silk artificially. [M][D][N][T]
Nanotube-polymer composite US researchers have produced a strong, tough composite made of single-walled carbon nanotubes and nylon. It employs "carbon spacers" to covalently link the nanotubes and nylon chains. The technique could open the way to produce other, similar mechanically tough composites from existing polymers and nanomaterials. [M][N]
Cheaper superhard material Superhard materials need to be highly incompressible and highly rigid. The conventional way to make them is to imitate diamond by using carbon and combining it with boron or nitrogen. Another approach, developed at UCLA, starts with soft but incompressible metals and tries to make them hard by incorporating rigid short covalent bonds. In 2005, the UCLA team combined the relatively soft element osmium, the most incompressible metal known, with small covalent-bond forming atoms of boron. They have now improved on this by using rhenium, which is next to osmium in the periodic table. Rhenium diboride is nearly as incompressible as diamond. Its hardness is comparable to that of cubic boron nitride, but it is cheaper to make. While other super-hard materials, including diamond and cubic boron nitride, are made under expensive, high-pressure conditions, rhenium diboride can be made by a simple process without applying pressure. [M][W]
Boron cage pseudo-metals A boron cage is an extremely stable molecule consisting of 12 boron atoms and 12 hydrogen atoms. Researchers at the University of Missouri-Columbia have found a way to modify these cages to produce a large, new family of nano-sized compounds. Attaching different compounds to the cages gives them the properties of various different metals, creating a range of new "pseudo" elements. The electron transfer properties of this new family of molecules span the entire range of those found within living systems. Because of this, these pseudo-metals may be tuned for use as specific probes in living systems to detect or treat disease at the earliest state. They may also have applications in nanotechnology and electronics. [M][G][H][J][N][P]
Hydrogen storage materials Chemists at UC Riverside have found that cyclic alkyl amino carbenes or CAACs can partly mimic the behaviour of metals and could be used in place of metals to develop carbon-based systems for storing hydrogen. [M][P]
Crystalline porous organic networks Reticular chemistry is the technology of linking molecules by strong bonds into predetermined structures. It has led to the creation of new classes of materials of exceptional variety. Covalent organic frameworks (COFs), developed recently at UCLA, are one of these new classes of materials and the first crystalline porous organic networks. Because of their functional flexibility and their extremely light weight and high porosity, COFs are of particular interest for storing hydrogen and methane as fuels and also for capturing carbon dioxide. A member of this series, COF-108, has the lowest density reported of any crystalline material and has a surface area of 4,500 square metres per gram. [M][E][N][P]
Super absorbent gel Japanese chemists have devised a gel that swells up to 500 times its size when in contact with solvents, an invention hailed as a breakthrough for absorbing dangerous industrial spills. The gel has been successfully tested on carbon tetrachloride, toluene, tetrahydrofuran and other common industrial solvents. [M][W]
Generating ultra-high pressures By combining diamond anvils and powerful lasers, laboratory researchers have developed a technique that should be able to squeeze materials to pressures 100 to 1,000 times greater than is possible today, reproducing conditions expected in the cores of supergiant planets. Until now, these pressures have only been available experimentally next to underground nuclear explosions. In a diamond anvil, a tiny sample is compressed between the tips of two diamonds. In the combined technique, several powerful laser beams zap one of the diamonds, vaporizing it and sending a shock wave through the sample that compresses it even more for a period of 1 to 2 nanoseconds - long enough to make measurements. The combined methods also allow experimenters to tune the temperature over a wide range independent of density, something almost impossible to do with laser-induced shock waves alone. [M][A][O] |
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| [E] Environment, transport and marine | |
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Biochar sequestration Carbon dioxide might be sequestered in soil by charring biomass. When returned to the soil, the resulting biochar creates a stable, long-term carbon sink, and also improves the structure and fertility of soils and enhances the retention and efficiency of fertilizers. Capturing the exhaust gases from the pyrolysis process produces energy in such forms as heat, electricity, bio-oil or hydrogen. Research at Cornell estimates that biochar sequestration in conjunction with bioenergy from pyrolysis should become economically attractive when the price of carbon credits reaches $37 per ton. [E][M][P]
IPCC WG1 report The Intergovernmental Panel on Climate Change (IPCC) has released the full text of the first of its four 2007 reports on global warming. This report covered the scientific basis and evidence for climate change. [E][C][D][P][R][X]
The PETM planetary crisis Scientists have strongly linked the Palaeocene-Eocene Thermal Maximum (PETM) to massive volcanic eruptions that occurred when Greenland and northwest Europe split apart some 55 million years ago to create the North Atlantic Ocean. The marine fossil record shows that during the PETM more than 2 trillion tonnes of carbon was released into the oceans and atmosphere in the form of methane and carbon dioxide. As well as raising sea surface temperatures, this acidified the world’s oceans and led to the extinction of numerous deep-sea species. The scientists were able to link the PETM to the volcanic eruptions through a layer of volcanic ash. The eruptions probably started about 61 million years ago. The mantle weakened progressively over the following 5 million years until the tectonic plate split apart. Some 10 million cubic kilometres of lava were erupted. Using radio-potassium dating, the scientists were able to precisely match a layer of volcanic ash that covers this lava with an identical layer of ash covering the ocean floor sediments of the PETM era. [E]
Antarctic climate cycles Researchers with the Antarctic Geological Drilling (ANDRILL) Programme have recovered a core of sedimentary rock more than a kilometre long from beneath the Ross ice shelf. The core will reveal information about water temperatures and ice-sheet and ice-shelf dynamics over the past 10 million years. During this period, there have been more than 50 oscillations in the ice margin, including periods when the Earth's climate was 2 or 3 degrees C warmer than today. Analysis of the core should reveal the extent of ice loss in West Antarctica during those warmer times and provide a firmer prediction about likely sea level rises from current global warming. [E][D]
Faster sea ice decline Research at NCAR and the University of Colorado shows that the Arctic's ice cover is retreating more rapidly than is predicted by any of the 18 computer models used by the Intergovernmental Panel on Climate Change (IPCC) in preparing its 2007 assessments. On average the models gave a 2.5 percent reduction per decade for the Arctic sea ice minimum, which occurs in September each year. The fastest rate in any individual model was 5.4 percent per decade. But newly available data sets, blending early aircraft and ship reports with more recent satellite measurements, show that the ice cover actually declined at a rate of about 7.8 percent per decade during the 1953-2006 period. This means the shrinking of summertime ice is now about 30 years ahead of the climate model projections. [E][A][C][P][R]
Global warming and hurricane intensity Several studies have suggested that increases in Atlantic surface temperature caused by global warming will lead to an increase in hurricane intensity. However, climate models also show that global warming will increase vertical wind sheer – differences in wind direction and speed between the upper and lower levels of the atmosphere. Historical evidence shows that higher levels of vertical wind shear make it harder for tropical storms to form and to intensify. Therefore this may counterbalance the effect of warmer surface temperatures, at least partially. [E][A][C][D][P][X]
Ocean carbon capture The result of two international expeditions to the Pacific Ocean suggests that carbon dioxide captured from the atmosphere at the surface is often consumed by animals and bacteria and recycled in the "twilight zone," a dimly lit area 100 to 1,000 metres below the surface. Because the carbon often never reaches the deep ocean, where it can be stored and prevented from re-entering the atmosphere as carbon dioxide, the oceans may have substantially less impact on changes in the atmosphere or climate than is predicted in current models. The findings affect proposals to mitigate climate change by fertilizing the oceans with iron to promote blooms of photosynthetic marine plants. [E][P][R]
Protecting the deep sea environment In a landmark deal between the nations of the South Pacific, a quarter of the world's oceans will be protected from bottom-trawling, which experts say destroys coral reefs and stirs up clouds of sediment that suffocate marine life. Observers and monitoring systems will ensure vessels remain five nautical miles from marine ecosystems at risk. The South Pacific contains the world's last pristine deep-sea marine environment. It extends from the Equator to the Antarctic and from Australia to the western coast of South America. [E][R] |
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| [R] Remote sensing and sensor systems | |
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Weather forecasting data The American Association for the Advancement of Science has issued a warning that budget cuts are threatening US satellites essential for weather forecasting, hurricane warning, and studies of global climate change. The AAAS says that declines will result in major gaps in the continuity and quality of the data gathered about the Earth from space. This warning reaffirms an earlier analysis by the US National Research Council, which concluded that US global observations are "at great risk" and that the next generation of US Earth-observing satellites are generally less capable than their current counterparts. However, there may be other ways to gather weather data: Boeing has filed a patent for equipping commercial airliners with radar systems that measure wind speed and direction. These instruments would send data back to a central computer, which would use it to update its model of the current weather systems. Commercial flight paths often pass over remote regions for which weather data is currently sparse. [R][A][E][P]
Galileo system validation GIOVE-A, the first Galileo satellite, has successfully transmitted its first full navigation message containing the information needed for users to calculate their position. The transmission is similar to those that will be sent by the full Galileo system and marks an important validation of the system design, according to ESA. It has two components: a navigation signal and a navigation message. The signal provides information that allows the user to measure the distance from the satellite to the receiver. The message contains the information needed to calculate the time and exact position of the satellite. [R][A][I]
Backup military navigation Soldiers may no longer need to rely on satellite navigation to pinpoint themselves or targets, if a new US military research project succeeds. The Robust Surface Navigation programme, funded by DARPA, aims to extract accurate positioning information from "signals of opportunity". These may include television and cellphone transmissions, if satellite signals are unavailable. [R][D][I][U]
Earth Observation Instrumentation A new space innovation centre in the UK will lead the development of novel technologies for Earth monitoring. Called the Centre for Earth Observation Instrumentation, it will pull together university and industry expertise. The initial priorities will be on new remote sensing technologies relating to atmospheric chemistry and how that relates to climate. The centre is a partnership between EADS Astrium, the University of Leicester, the UK's Science and Technologies Facilities Council, QinetiQ, and the Rutherford Appleton Laboratory. [R][A][E][P][S]
TeraHertz imaging MIT and Sandia report they have demonstrated a real-time THz imaging system that obtains images from 25 metres away. It uses 4.9 THz radiation generated by a quantum cascade laser. At most frequencies, THz radiation is strongly absorbed by molecules in the atmosphere and therefore THz imaging can only be done at short range. But at 4.9 THz there is a transmission window where the absorption is low. [R][J][O][S]
Laser sensing of anthrax Physicists at Texas A&M and Princeton have developed a laser technique to identify anthrax spores in real time. It is based on coherent anti-Stokes Raman scattering (CARS), which very sensitively detects the shifts in the energy of photons when they are scattered by vibrating molecules. The researchers were able to separate the signal from anthrax molecules from that of extraneous surrounding molecules. To do this they used two broadband femtosecond laser pulses to excite the target molecular vibrations followed by a time-delayed longer narrowband pulse to measure the anti-Stokes signal. The researches say the technique works whether the anthrax is in mail or dispersed in the atmosphere and that it has many other potential applications. [R][D][E][H][O]
Fusing medical images Combining 3-D medical images from more than one date or more than one source, such as MRI and CAT, can enable radiologists to diagnose features more accurately and more easily detect structural changes, such as the growth or shrinkage of tumours over time. To be combined, the images must be precisely registered using computer-enhanced 3D alignment. The speed and accuracy with which this registration can be done has now been greatly improved by the use of parallel computer architecture and memory bandwidth, according to researchers at Mayo Clinic and IBM. [R][C][H][K]
3-dimensional imaging Japanese researchers have shown that it is possible to construct a local 3D model using a camera flash. To obtain just the flash information the camera takes a picture with flash and then one without, and subtracts one from the other. Comparing the pattern and strength of this reflected light allowed them to estimate the distances to, and the relative angles of, different surfaces in a complex scene such as a room. [R][C][O][U] |
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| [S] Sensor devices | |
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Smart sensor networks Simple infrared motion sensors similar to those used to control automatic lights can be used as a network to monitor the movements of people inside a building. Knowing where groups congregate can be used to save energy and improve safety by, for example, turning down the air conditioning when there are only a few people in one part of the building or directing people to the best available escape routes in an emergency. Importantly, because the sensors only detect movement and cannot image or recognise individuals, there is less risk that the network would be accused of spying on people. [S][R][W]
Nanoscale imager Magnetic Resonance Force Microscopy (MRFM) combines aspects of atomic force microscopy (AFM) with magnetic resonance imaging (MRI). Interest in this technique is driven by the hope of attaining the "Holy Grail" of microscopy: three-dimensional imaging of complex structures such as molecules with atomic resolution and chemical specificity. IBM researchers report that they have made an important advance by demonstrating MRFM imaging at the nanoscale for the first time. Achieving MRFM with single-nucleus sensitivity still remains a long way off, however, because the magnetic force generated by an individual nucleus is so tiny - only about 10 zeptoNewtons. [S][G][J][N][O][R]
Nanowire photodetectors Nanowires make supersensitive photodetectors and, in theory, can achieve single photon sensitivity, according to researchers at UCSD. The wire's active volume that produces dark current noise is only one thousandth that of a normal size photodetector, and the wire's large surface area traps holes very efficiently, preventing the photoexcited electron-hole pairs from recombining quickly. Both factors enable nanowire detectors to achieve very high sensitivity, provided that light can be efficiently coupled into the nanowires. Several methods have been proposed to achieve light coupling efficiency, such as placing the nanowires in an optical resonant cavity. [S][N][O]
Foetal heart monitor A foetal heart monitor the size of a mobile phone has been developed at Nottingham University and is in clinical trials. The researchers say that the device is sufficiently small and easy to use that mothers-to-be can keep a regular check on their baby's heart without having to go into hospital. Currently hospital based ultrasound is used to record babies' heart rates during pregnancy, but this needs to be administered by trained professionals. The new technology should provide the capability for routine, continuous, long-term monitoring, particularly of high risk pregnancies. It works by detecting nanovolt electrical signals present on the maternal abdomen and by using advanced signal processing to separate the foetal heart beat from the much stronger signal from the mother's heart. The foetal signals can be detected from 20 weeks onwards. [S][H][R]
Cancer screening Researchers at UCSD report that they have achieved proof of principle of a new method for detecting cancer very early in its development, when it consists of just a few cells. The best existing detection methods are not able to detect a tumour until it consists of about one million cells. The new methods exploits the fact that when a cancer cell mutates, it often brings together two pieces of DNA that are normally apart. The researchers developed an enzyme reaction that works well only when two DNA pieces that are normally separated are close together. This technology amplifies the mutant DNA and then uses a microarray to identify the specific mutation. [S][G][H]
Progress in cancer screening New non-invasive diagnostic techniques are being developed that can detect early stage cancer from molecular signals in breath, blood and other body fluids. Recent research shows that DNA recovered from exhaled breath can reveal the state of cells that line the lungs, particularly by looking to see if the DNA has been methylated in ways that inhibit tumour suppressor genes. Other research shows that a simple oral rinse could detect the early development of head and neck squamous cell carcinoma. Thirdly, recent research shows that the identification of cancer signatures in blood can be enhanced using hydrogel nanoparticles that can function like "smart" sponges and soak up specific proteins in the bloodstream. [S][G][H][N]
Protein sniffing The nose has does not have a specific sensor for each smell; rather, it responds to the pattern of responses produced by multiple, generalised receptors. US researchers have mimicked this using a solution containing 2 nanometre gold nanoparticles with different coatings. The coatings are made from slightly different organic molecules containing nitrogen atoms. An odour protein binds to multiple receptors but attaches more easily to some than others. The pattern of bindings can be measured using a fluorescent signal molecule that attaches to the receptor particles but is displaced by a protein when it binds. The more this molecule is displaced, the more light it produces. The relative strengths of these light signals then provides a signature for the odour protein. In blind tests with 56 random proteins, the recognition accuracy was 96 percent. The aim is to use this artificial nose for detecting diseases by sniffing out imbalances in the usual combination of proteins in body fluids. [S][G][H][N][O][V]
Electronic nose A substance that mimics mucus has been used by UK researchers to significantly improve the performance of odour-sensing "electronic noses" in picking apart complex smells. In a human nose, the layer of mucus dissolves scents and separates their components chemically, using chromatography. Different odour molecules then reach smell receptors at slightly different times providing a temporal signature that helps in recognising different smells. [S][G][N][V]
Weighing living cells Current mass-measurement methods achieve a resolution down to a zeptogram, but the procedure cannot be used on living cells as it has to be performed inside a vacuum. MIT researchers have devised a way to allow living cells to remain in fluid while they are being weighed by putting the sample and fluid inside the mass-measuring silicon cantilever instead of on top of it. The cantilever itself still vibrates in vacuum as before, but the sample is shielded. So far, the researchers have weighed particles with a resolution down to slightly below a femtogram. They believe this resolution can be improved by several orders of magnitude. The technique could allow researchers to develop inexpensive, portable diagnostic devices and might also offer a unique glimpse into how cells change as they undergo cell division. [S][G][J][N] |
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| [O] Optoelectronics, optics and lasers | |
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Cloaking Cloaking objects to make them invisible has so far been demonstrated only for small objects and at long range. A computer model designed by a mathematician at the University of Liverpool has now shown that it should be possible to make objects, including aircraft and submarines, appear invisible at close range. [O][C][D][M][N][R]
Optical shape-change crystals Japanese researchers have made crystals that change their shape in response to light. The crystals are made of molecules that are Y-shaped. UV light causes a new bond to form near the branch of the Y, creating a carbon ring that twists the shape. The small movements of each molecule add up to cause the whole crystal to twist. The structure can expand or contract by about 7 percent in about 25 microseconds. These shape change crystals might be used in optical systems and in place of piezoelectric actuators in situations where it is difficult to use an electric field. [O][M]
Low power optical memory Researchers at Southampton University have shown proof of principle of a four state all-optical memory that can be switched with very low power. The researchers say the memory would require a tenth of the power of current systems like DVDs. Their prototype device uses laser pulses to switch the atomic structure of a tiny gallium particle among four states, thereby storing two bits per particle. [O][C]
Single attosecond XUV pulses Researchers in Italy have developed a method to create single pulses of extreme-ultraviolet light that last for only 130 attoseconds. These isolated attosecond pulses should make it possible to probe electron phenomena such as wavepackets inside atoms and molecules. They are a step forward in using lasers to change the course of chemical reactions for scientific and practical uses, such as controlling the breaking of bonds in complex molecules for medical and pharmaceutical applications. [O][G][M][N]
Electron tunnelling observed European and Russian researchers have used attosecond laser pulses to observe electrons tunnelling out of atoms. The ultra-short laser pulses revealed discrete stages of this ionization process, each of which lasts 100 attoseconds. The experiments provide the first observation of the dynamics of electron tunnelling and demonstrate how the movement of electrons in atoms or molecules can be observed in real time by means of laser field-induced tunnelling. The researchers say this has wide applications - in microelectronics, the development of compact x-ray light sources, biological imaging and radiotherapy. [O][G][H][J][M][N][R]
Producing photon pairs Researchers at NIST have devised a paired-photon source that delivers high numbers of photon pairs over a broad bandwidth with low noise, all in a compact device for quantum communication. The system uses a microstructured optical fibre. This has a slender glass core at the centre of an array of hollow channels, giving it a honeycomb appearance in cross-section. The structure tightly restricts the way light can travel down it, increasing the intensity of light in the thin central core and thereby greatly increasing the probability of pair production. [O][I]
Entanglement sudden death A strange quantum phenomenon that could be a stumbling block to building quantum computers has been observed for the first time by physicists in Brazil. Known as entanglement sudden death (ESD), it involves the rapid decay of the "entangled" pairs of particles that will be central to the operation of quantum computers. Since the particles decay so quickly, the physicists claim that the decay cannot be reversed using the error-correction schemes that have been proposed to increase the lifetimes of entangled particles. Whilst not precluding quantum computing, ESD may set a limit to the duration of a quantum calculation. [O][C] |
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| [I] IT, communications, networking and secure systems | |
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324 GHz CMOS oscillator Researchers at UCLA have generated a 324 GHz signal using a voltage-controlled oscillator made in a conventional 90-nm CMOS technology. They first generated a fundamental frequency of 81 GHz with phase-shifted outputs at 0, 90, 180 and 270 degrees, respectively. By linearly superimposing these four rectified phase-shifted outputs in real time, they generated the 324 GHz waveform. Their next step is to produce a 340 GHz signal, matched to the 340 GHz atmospheric window, a frequency at which radiation is not absorbed by the atmosphere and can propagate long distances. [I][A][J][O][R][S]
Internet in space The US Department of Defense's Iris project will put an internet router in space by the start of 2009. Iris (Internet Router Protocol in Space) will allow voice, video and data communications for US troops using standards developed for the internet. Eventually Iris could extend the net into space, allowing satellites to communicate directly with one another using internet protocol (IP). At the moment most satellites have to communicate with one another through ground stations or via radio signals to a relay satellite. [I][A][K]
Ethernet-to-the-home Demand for high-speed Internet access is forecast to grow sharply with the increasing availability of video on demand, teleworking and easier access to government services. A Eureka project has demonstrated an order of magnitude improvement in data rates over existing cable TBV networks, with no need for a consumer modem. In a pilot trial in the Dutch town of Boxmeer, all 28,000 local residents have been given symmetrical access to the Internet at 10 MB/s, with local businesses able to obtain 50 MB/s symmetrical data connectivity. The technology has subsequently been developed to provide 100 MB/s connectivity. [I][K][O]
Future cellphone Mobile phone handset manufacturers are reported to see GPS-based navigation as one of the next major value-adding offerings on cellphones. Analysts estimate that the annual market for phone navigation is worth hundreds of millions of euros. Google and Yahoo are also racing to bring consumer services such as information search to mobile phones. Already, mobile television is proving more popular than predicted. Services in Japan, South Korea and Italy are attracting millions, confounding critics who said people would not watch TV on a small device. [I][J][K][R][V]
e-Readiness The annual e-readiness rankings by the Economist Intelligence Unit shows that the basic technologies that people use to go online are now becoming common worldwide and that Asian and African nations are catching up. Broadband, in particular, is now affordable almost everywhere. Denmark remains in top place on e-readiness, with US and Sweden in joint second place. The UK has slipped to seventh place. A new report by the UK Broadband Stakeholder Group warns that tough decisions must be made on how to encourage telecoms firms to update the UK's telecoms infrastructure to handle very high-speed broadband. [I][K]
Rise in malicious code The number of new pieces of malicious software has doubled in the last year with the web being used increasingly to distribute the code, a report says. In the first quarter of 2007, security firm Sophos identified 23,864 threats, up from 9,450 on this time last year. In the same period the firm said it was identifying 5,000 web pages per day infected with so-called malware. In a separate report, security firm MessageLabs warned that it is beginning to see spam e-mails that also contain a virus. [I][K] |
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| [K] Knowledge, information and technology management | |
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Encyclopaedia of life A project has been launched by some of the world's leading scientific institutions and universities to compile everything known about all of Earth's 1.8 million known species and put it on one open Web site. The effort, called the Encyclopaedia of Life, will include species descriptions, pictures, maps, videos, sound, sightings by amateurs, and links to entire genomes and scientific journal papers. The project will take about 10 years to complete. [K][E][G][X]
Global mapping Freely available global mapping software, such as Google Earth, is rapidly being adopted by environmental scientists as a cheap and effective way to display, compare and combine data. [K][C][D][E][R][V] |
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| [C] Computing, supercomputing, modelling and simulation | |
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Playstation supercomputer network More than 250,000 PS3 owners have enrolled their console in the Folding@Home project, which uses idle time on each machine to study the way proteins fold. Proteins that do not fold correctly have been implicated in diseases such as Alzheimer's and BSE. The average computational power delivered collectively by the enrolled machines is about 400 teraflops, and the maximum so far has been 700 teraflops. By comparison BlueGene L, which tops the list of the world's most powerful supercomputers, has a top speed of 280.6 teraflops. [C][G]
Pan-European supercomputer Under the newly launched PACE initiative, the scientific supercomputing centres of 15 European countries are being linked into a single infrastructure. [C][I][K]
EDGE architecture chip Researchers at the University of Texas have completed the design and build of a new general-purpose microprocessor architecture known as TRIPS (Tera-op, Reliable, Intelligently adaptive Processing System). TRIPS uses a new instruction set architecture called Explicit Data Graph Execution (EDGE) that allows execution to be easily broken down into large groups of instructions (graphs) that can be run on independent processing elements. The prototype TRIPS processor contains 16 such elements, but it is expected this will rapidly scale up to 128 in "real world" processors in the near future. Combined with a number of novel architecture changes, the TRIPS designers hope to reach 1 teraflop on a single processor by 2012. [C][I][J][K][R][T]
Control of qubit coupling Quantum computing involves manipulating the quantum state of qubits in time sequence. For this, it is necessary to control the states of individual qubits and the states of two qubits for logic operations, and to have the ability to turn the coupling between qubits on and off. Scientists from NEC, JST and RIKEN have successfully demonstrated the world's first qubit circuit that is able to control the strength of coupling between qubits. The pair of qubits is coupled via a third control qubit inserted between them. This functions as a non-linear transformer that is able to turn the magnetic coupling between the two qubits on and off in response to a microwave signal. The researchers showed that the coupling operation does not shorten the lifetime of each qubit. It should be easy to scale the circuit in size by repeating the coupled qubit units. [C][J]
Brain simulation IBM scientists have simulated half a virtual mouse brain on the BlueGene L supercomputer. The virtual brain had 8 million neurons each with up to 6300 synapses. The vast complexity of the simulation meant that it was only run for 10 seconds at a speed ten times slower than real life - the equivalent of one second in a real mouse brain. For future tests the team aims to speed up the simulation and to make it more neurobiologically faithful, adding structures seen in real mouse brains and making the responses of neurons and synapses more detailed. [C][B][K][V][X]
Computational photography Today's editing of digital images is just a prelude to the revolution of full computational photography. Digital images can be adjusted, analysed or combined to create new images and art forms, and to extract or preserve more detail. It is no longer necessary to start with a conventional camera or image. Researchers are experimenting with distorting the field of view, using arrays of microlenses or virtual lenses that exist only in software, three-dimensional apertures, multiple exposures, and camera arrays. Some use "smart flashes" to illuminate a scene with complex patterns of light, or set up domes containing hundreds of flashes to light a subject from many angles. Medicine and science could benefit from imaging techniques that transcend the limitations of conventional microscopes and telescopes. The military is interested in using camera arrays to see through dense foliage. Robots can use computational imaging to map their environment. [C][D][E][K][O][R][S][T][U][V][W] |
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| [W] Whole life engineering, manufacture and testing | |
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Building web 2.0 Web 2.0 is about enabling and encouraging active user participation through open applications and services. Its goal is to encourage all "web citizens" (webizens) to create, share, extend, distribute and enjoy ideas and information. To reach this goal, systems must be simple to use, highly scalable, and rich in sensible content. Among these qualities, sensible content is the toughest to achieve and will experience the most technological breakthroughs. Despite progress in search engines, recommender systems and mashups, the capabilities to produce and manage collective intelligence are still quite immature. [W][C][K][T][X]
IT Services Management The Information Technology Infrastructure Library (ITIL) is a collection of interrelated books that provide best practice guidelines on IT Services Management (ITSM). ITIL Version 3 - an update incorporating a life-cycle approach and latest best practice - is scheduled to be published at the end of May 2007. It consolidates the essential ITIL processes into five core volumes: Service Design, Service Strategies, Service Transition, Service Operation, and Continual Service Improvement. [W][C][K][T][X]
Investing for resource sustainability In an article in McKinsey Quarterly, Al Gore and his partner David Blood, the former head of Goldman Sachs Asset Management, argue that companies face big changes driven by environmental and resource pressures. Investing for resource sustainability is essential to creating long-term shareholder value. This involves assessing the way social, economic, environmental, and ethical factors affect the strategy and valuation of businesses. Approaches to socially responsible investing are changing, as well as society’s widening expectations of corporate responsibility. They discuss how to gain superior returns for investors while integrating sustainability into an investment model, and the complexity of valuing companies across multiple dimensions of sustainability. [W][E][P][X] |
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| [X] Systems, complexity and risk | |
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Productivity of cities Cities are on the brink explosive growth. Today a little more than half of the world's population lives in large urban areas. By 2030, this is expected to increase to two-thirds. A study of the growth of cities in the US, Europe and China over the past 150 years has come up with general equations that can predict cities' consumption of resources and their contributions to society. The researchers measured the cities' consumption of resources (such as water), their requirements for infrastructure (such as roads, transportation, lengths of electrical cable) and their creative output (such as patents issued, "super creative jobs" generated, R&D employment, total wages). City size was measured in terms of population. The researchers found that as a city grew in size it required less energy per capita to sustain it. However, the rate of creative output scaled superlinearly - as the city grew its creative output grew faster and faster. [X][E][K][W]
Climate engineering An article in IEEE Spectrum puts the case for a major research effort now on how to geoengineer the world's climate, in case the world fails to control global warming by other means. At present, geoengineering technologies are far too speculative to be a serious option. The scientific understanding, tools and skills are clearly insufficient and the consequences of getting it wrong could be catastrophic. The article cites nine possibilities, ranging from putting up space shields or using chemicals to reflect sunlight or to increase Earth's cloud cover to stimulating massive growth of phytoplankton in the oceans and huge reforestation projects. These early ideas probably offer only a glimpse of what might eventually unfold. [X][A][C][D][E][I][K][P][R][T][U][W]
Global social networks A study of cellphone calls between more than four million people has shed new light on the way social networks organise on such huge scales. It indicates that global networks depend on weak links rather than strong links. This is unexpected because in most biological or technology networks it is the strong ties that play the most importance structural role. However, in global social networks strong ties are usually within local communities, so their removal only disintegrates the local community. Removing the weak ties destroys the links between different communities. The results also suggest that information spreads most quickly via links of intermediate strength and via medium length calls. This is because information spreads slowly through weaker links and shorter calls, and stronger links tend to bind only a limited number of people. [X][D][H][I][K][V]
Electromagnetic safety Further research is still needed to determine the impact of electromagnetic fields on health, particularly in the long term, according to the European Commission's Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR). Sources of exposure include power lines, electrical appliances, mobile phones, video displays, anti-theft devices in shops, card readers and certain diagnostic instrumentation such as MRI equipment. A lot of research has been carried out on RF exposure from mobile phones. However, little is known about the health risks associated with long term exposure to low levels from other sources. [X][B][C][H][I][P][R][S]
Road deaths Nearly 400,000 young people under the age of 25 are killed in road traffic crashes every year, making this the leading cause of death in the 10-24 years age group, according to the WHO. Millions more are injured or disabled. The vast majority of these deaths and injuries occur in low- and middle-income countries, and the highest rates are in Africa and the Middle East. Young people from economically disadvantaged backgrounds are at greatest risk in every country. [X][B][D][H][R] |
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| [V] Virtuality and human-machine interface | |
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On-screen legibility The low resolution of computer screens means that reading on screen can be harder and more tiring than reading printed text. This is seriously affecting productivity as more and more material is read onscreen. The colour LCD screens on most laptops and desktops today have a resolution of only about 100 pixels per inch. At least two or three times that many pixels are needed to begin to approach the quality of the printed page. New fonts have been developed that perform better on screen. Verdana, released in 1996, was created just for use on computers. Microsoft Vista has 6 new high legibility fonts: two serif faces, called Cambria and Constantia; two sans-serif faces, Calibri and Corbel; a flared-serif face, Candara; and a monospaced face for programmers, Consolas. [V][B][K][T][W]
A4-sized electronic paper South Korea's LG Philips LCD has announced that is has developed the world's first A4-sized colour electronic-paper. It can display up to 4,096 colours and uses power only when the image on the paper is changed. [V][I][K][M][O]
Music recognition and synthesis Computers are learning to understand music, but the task is hard - similar in nature and difficulty to speech recognition and speech synthesis. Though software can reliably identify the notes of a single melodic line played by one instrument in isolation, sorting out the complexity of a full orchestra is quite different. Progress is being made with machine learning techniques that allow computers to learn how to analyse music from many examples. Computers can also line up a score with a recording of its performance, and this capability is used to fine tune and correct performances for perfecting recordings and even live performances. The ability to read a score also enables a computer to be an excellent accompanist allowing soloists to practice with a virtual full orchestra. [V][C][K][T][U]
MRI-enabled robot surgery A commercial surgery robot that will allow doctors to perform microscopic operations on the brain is expected to be used in its first operation this summer. The robot is compatible with MRI and will enable neurosurgeons to perform their riskiest work while patients lie within an MRI machine, giving a clear 3D picture of even the smallest nerves. This enables surgery on lesions such as brain tumours that human surgeons are simply not dexterous enough to perform unaided. [V][B][H][R][U]
Deep brain stimulation Deep brain implants may provide an alternative to retinal implants for restoring vision, according to researchers at Harvard Medical School. In experiments on macaque monkeys, they showed that visual inputs can be produced by stimulating the lateral geniculate nucleus (LGN), an area deep in the centre of the brain that relays signals from the retina to the cortex. The LGN was previously thought to be too difficult to reach. But surgical advances for deep brain stimulation, including treatment used for movement disorders such as Parkinson's disease, have made accessing it relatively easy, via a single small hole in the skull. [V][B][H]
Deep brain stimulation Deep brain stimulation (DBS) might help patients suffering from very severe depression that cannot be brought under control with medication or other therapy. Doctors at the University Clinics of Bonn and Cologne treated three such patients with DBS. Two improved dramatically within a few days, and initial changes were even noticeable in a matter of minutes. [V][B][H] |
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| [B] Brain research and human science | |
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Retinal repair In adult mammals, including human begins, tissue within the central nervous system has very little capacity to regenerate. This is partly due to the formation of barriers, known as "glial" scars, which are triggered by the body to protect injured nerve tissue from further damage. The glial barrier blocks foreign cells, including transplants meant to heal and regenerate. Scientists in Boston have now found that a molecule known as MMP-2 (which is induced by stem cells) has the ability to break down glial barriers on the outer surface of a damaged retina. This allows healthy donor cells to integrate and wire themselves into remaining recipient tissue. The finding holds great promise not only for patients with retinal disease, but for those with spinal cord injuries and neurodegenerative disorders such as Parkinson’s and Alzheimer’s. [B][G][H]
Evolution of the nervous system Vertebrates have a central nervous system (CNS) in the form of a spinal cord running along their backs. Insects and annelid worms like the earthworm, in contrast, have a rope-ladder-like chain of nerve cell clusters on their belly side. Other invertebrates have their nerve cells distributed diffusely over their body. Because of these differences, it was supposed that even though these species all evolved from a common ancestor called Urbilateria, they must have separately evolved their CNS. However, researchers at EMBL studying a marine worm called Platynereis, have found this supposition is wrong. Platynereis is a "living fossil" preserving many ancestral features including a prototype invertebrate CNS. The researchers found that the way that the CNS develops in a Platynereis embryo is so similar to that in vertebrates that the CNSs cannot have evolved independently. This supports an old theory that vertebrates turned themselves upside down through the course of evolution, moving their CNS from belly to back. [B][G]
Origin of language All primates use vocal and facial expressions to communicate, but only the great apes use gestures as well, an ability they share with humans. Researchers from Emory University have studied the way bonobos and chimpanzees use hand and limb gestures and have found that apes use gestures more flexibly than facial and vocal expressions. Also, when apes gesture, they use their right hand, which is controlled by the left side of the brain - the same side as the language control centre in the human brain. The researchers say that their findings support the theory that human language developed through the use of hand gestures. [B][K]
Memory and sleep If the brain has to learn two sets of similar but different information, memorising the second group can interfere with the memory of the first. Researchers have found that sleeping after learning the first group strengthens that memory and also protects it from subsequent interference. [B][K]
Memory and sleep New research suggests that sleep not only strengthens the content of a memory but also memory of the particular order in which events were experienced. Students were asked to learn triplets of words presented one after the other. Afterwards they slept, whereas in a control condition no sleep was allowed. Later, recall was tested by presenting one word and asking which one came before and which one came after during learning. Sleep was found to enhance word recall, but only when the students were asked to reproduce the learned words in the forward direction. [B]
Relational memory takes time and sleep Previous research has shown that sleep actively improves task-oriented "procedural memory", such as learning to talk, to coordinate limbs, musicianship, or to play sports. A new study demonstrates sleep also improves relational memory - the ability to make logical "big picture" inferences from disparate pieces of information. The results strongly imply that sleep is actively engaged in cognitive processing of memories. The results also showed this knowledge-creating process occurs even whilst awake, but particularly during sleep. [B][K]
Possible drug against Alzheimer's disease In Alzheimer's disease, the action of a key enzyme on amyloid precursor protein leads to the formation of the toxic beta-amyloid plaques. By inhibiting this enzyme, called memapsin 2 or beta-secretase, it should be possible to prevent plaque formation. However, finding a drug to block memapsin 2 has proved difficult, because a very similar enzyme, memapsin 1, is involved in many important biological processes. Researchers at Purdue have now announced that they have developed a clinically suitable inhibitor compound that selectively targets memapsin 2 without affecting memapsin 1. This could provide the first drug treatment for Alzheimer's disease, particularly in conjunction with new advances in diagnosing Alzheimer's disease at an early stage. Recent research has shown that early Alzheimer’s could be diagnosed with an accuracy of around 84 percent from electroencephalogram (EEG) signals, a technique suitable for use in local surgeries. [B][H]
Alzheimer's disease and diet Diets rich in docosahexaenoic acid (DHA), a type of omega-3 fatty acid, may help to prevent the development of Alzheimer’s disease later in life, according to research at UC Irvine. The study on genetically modified mice shows that DHA can slow the accumulation of tau, a protein that leads to the development of neurofibrillary tangles. DHA was found to also reduce levels of the protein beta amyloid, which can clump in the brain and form plaques, the other Alzheimer’s lesion. Previous studies have shown that DHA may have therapeutic value for Alzheimer’s patients, but this research is among the first to show that it may delay the onset of the disease. DHA is found in fish, eggs, organ meats, micro-algae, fortified foods and food supplements. [B][G][H] |
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| [H] Healthcare and medicine | |
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Transgastric surgery Future abdominal surgery may be done via the mouth without the need for any incision in the skin, following the results of successful trials. Much of the discomfort and recovery time after conventional surgery - even keyhole surgery - is due to the incisions made in the abdominal wall. Instead the surgeon gains access to the abdomen via the stomach lining. This is relatively painless, making it possible for the procedure to be carried out under mild sedation rather than general anaesthetic. The risk of infection is low because stomach acid is lethal to bacteria. Going in through the stomach may also reduce the risk of post-operative infections with, say, the drug-resistant superbug MRSA, which often lives on the skin. [H]
Biotech drugs A US study estimates that biotech drugs will comprise a quarter of all spending on prescription drugs in five years, driven by broader uses for cancer and arthritis treatments. Spending on biotech drugs climbed 21 percent in 2006, compared with 6 percent growth for traditional chemical-based pharmaceuticals. [H][G]
New antibiotics To speed up the hunt for new antibiotics to counter drug-resistant bacteria, researchers at the University of Wisconsin have developed a way to test large numbers of molecules quickly and efficiently. Potential drug compounds are synthesised directly on a flexible, paper-like sheet, building from the bottom up by adding ingredients one at a time to sections of the sheet. The finished array has dozens of compounds arranged in a grid of dots. Each array is subjected to a battery of tests, simultaneously testing the potency of each of the compounds against various strains of bacteria. So far the technique has identified four new classes of antibiotic whose potential was previously unknown and which probably fight bacteria in novel ways. Encouragingly, the strongest activity was against MRSA and related strains, known as Gram-positive bacteria. Gram positive bacteria include many well-known genera such as Bacillus, Listeria, Staphylococcus, Streptococcus, Enterococcus, and Clostridium. [H][G] Vaccine against prion diseases Scientists at New York University say they have developed a vaccine that stops mice getting a brain disease similar to BSE and which may ultimately protect humans against vCJD. The prototype vaccine was made from prion proteins attached to a genetically modified strain of Salmonella. This bacterium is already used in a number of animal and human vaccines. [H][G]< | |||