|
|
|
|
|
|
|
|
|
Top Stories in Science
|
September 2007 Issue |
||
| [D] Defence and security |  |
||
|
|
|
|
|
Opening of the Arctic The Northwest Passage, the most direct shipping route from Europe to Asia, is now fully clear of ice for the first time since records began. Satellite images of sea ice show a "fully navigable" route between the Atlantic and the Pacific. The Northeast Passage through the Russian Arctic remains partially blocked, but may well open sooner than expected as large areas of the Arctic sea-ice are only one metre thick this year, half the thickness in 2001. Canada claims full rights over those parts of the Northwest Passage that pass through its territory and says it can bar transit there. This is being disputed by the US and the EU, which argue that the new route should be an international strait that any vessel can use. [D][E][R]
Better news on H5N1 Researchers in Belgium have developed an adjuvant that boost the effect of an H5N1 vaccine by six times. This would allow many more people to be vaccinated in the event of a pandemic. [D][H]
Better news on H5N1 Researchers at St. Jude Children's Research Hospital have reported that the H5N1 bird flu virus is still a long way from becoming a deadly pandemic strain. They examined samples from people who have become infected with H5N1. These included seven Indonesians killed in a cluster, who infected one another through human to human transmission of the virus. The researchers identified 32 very strong genetic changes that differentiate human flu from a bird flu. The devastating 1918 Spanish flu virus had made 13 of these mutations, putting it roughly halfway between a bird virus and a human virus. In contrast, none of the samples from the human H5N1 patients showed more than two of the changes. The understanding of what mutations would make the H5N1 more dangerous is being used to develop vaccines that target potential future pandemic strains. [D][H]
Defeating a new virus Researchers at Penn State may have discovered a universal mechanism to create weak strains of viruses that can be used safely as vaccines. They identified a key amino acid in the polymerase of poliovirus that controls the speed and accuracy with which the virus is able to multiply. By replacing this with different amino acids, they were able to dramatically weaken the replication and generate mutants of the virus that are essentially harmless. Since all viruses have a similar mechanism regulating their replication, the researchers hope the discovery may open the way to quickly produce vaccines against other viruses such as influenza, SARS, Dengue fever, ebola and the West Nile Virus. It might also enable vaccines to be rapidly produced against any virus used as a biological weapon. [D][G][H]
Future food supply Spreading deserts and degradation of farm land due to climate change will pose a serious threat to food supplies for the world's surging population in coming years. According to the UN World Meteorological Organisation (WMO), the crunch could come in just over a decade as all continents see more weather-related disasters like heat waves, floods, landslides and wildfires. [D][E][X]
Millennium goals for 2015 In a speech to the UN in New York, the UK Prime Minister Gordon Brown called for a new global alliance to meet the Millennium Development Goals. So far these goals, on illiteracy, disease, poverty, environmental degradation and under-development, are not being met. He argued for emergency action by public, private, voluntary sectors, faiths and international institutions. The gains from global prosperity have been disproportionately enjoyed by the people in industrialised countries, but the consequences of climate change will be disproportionately felt by the poorest who are least responsible for it. [D][E][H][K][W][X]
Public health security A WHO report warns that world is at increasing risk from disease, industrial accidents, natural disasters and other health emergencies. Infectious diseases are spreading faster than ever before. Since the 1970s, new diseases have been emerging at the rate of one or more per year, and with over 2 billion airline passengers a year, there is a high risk of epidemic. The revised International Health Regulations adopted in 2005 have now come into force and are helping countries to work together to identify, contain and control risks. But increased effort is still needed to combat disease outbreaks and in sharing virus data to develop vaccines. [D][A][E][H][X]
Public health security About 40 percent of deaths worldwide derive fundamentally from water, air and soil pollution, according to researchers at Cornell University. They examined data from more than 120 published papers on the effects of population growth, malnutrition and various kinds of environmental degradation on human diseases. They conclude that environmental degradation, coupled with the growth in world population, are major causes behind the rapid increase in human diseases reported by the WHO. [D][A][E][H][X]
Effects of military overstretch Research at King’s College London on the effects of prolonged military deployments among Britain’s armed forces has found that troops who were deployed for 13 months or more over a three year period were more likely to have symptoms of post traumatic stress disorder and problems at home during and after deployment. This was particularly apparent in those with direct combat exposure. The prevalence of severe alcohol problems also increased with longer deployment. Another study funded by the US DOD that surveyed 1,114 US Air Force women deployed during the Iraq war has found that 20 percent report they are experiencing at least one major symptom of post-traumatic stress disorder (PTSD). The researchers found that women who experienced higher levels of family-work conflict were more likely to have symptoms of depression and anxiety, and were also less likely to feel they could cope with daily demands and responsibilities. [D][B][H] |
|||
| [A] Aeronautics and space | |
||
|
|
|
|
|
Ground skimming rotorcraft A US company, Moller International, has begun production of a flying, two-passenger, saucer-shaped vehicle that is designed to take off and land vertically. It is the size of a small car, powered by eight rotary engines, and intended to fly up to 3.5 metres above the ground. An on-board computer system prevents it from entering regulated airspace. The prototype has already completed over 200 flights, some with, and some without a pilot. [A][P][U]
Cheap flight lifestyle Britons are "addicted" to cheap flights and confused about the climate impact of flying, according to a UK study. It found that even people living generally "green" lives said they were reluctant to fly less. Domestic aviation contributes less than 1 percent of Britain's carbon dioxide emissions. International flights are a much bigger issue, with the carbon dioxide from all flights leaving the UK amounting to nearly 7 percent of the national total. [A][E][X]
Space tourism Bigelow Aerospace, which has successfully placed two inflatable spacecraft in Earth orbit, has announced that it intends to launch its "Sundancer" space station into orbit in 2010. The inflatable station will be able to support a crew of three. Another company called Galactic Suite has announced that it intends to put a three-bedroom space hotel in orbit by 2012. [A][M]
The Orion mission A feature article in the October issue of Scientific American explains how the NASA Orion mission to the Moon will work. It describes the major engineering challenges that must be tackled, the launchers and spacecraft being developed, and current concepts for scientific missions that may be set up on the Moon. [A][M][P][T][U]
Lunar base NASA's Lunar Architecture Team is evaluating possible designs for a future lunar base. The design must be able to withstand launch and provide sufficient room for the planned four-person crews. It must also give sufficient protection from the temperature extremes, space radiation, micrometeorites and abrasive dust on the Moon. [A][M]
Solar vibrations Churning motions inside the Sun produce various kinds of waves, including sound waves called p-modes and surface waves called g-modes. The p-modes vibrate with periods of a few minutes and the g-modes have period of tens of minutes to several hours. In the mid-1990s, the Ulysses spacecraft found apparent fluctuations in the solar wind with periods in the same range as p-modes and g-modes. Researchers now say they have evidence that these modes also influence natural phenomena and human technologies on Earth. They say that voltages on undersea communications cables have unexplained fluctuations with periods characteristic of p-modes, that seismic measurements show periods in the range of g-modes, and that the number of dropped mobile phone calls seems to fluctuate regularly with periods that could tie them to solar vibrations. However it is unclear what mechanisms could possibly produce such coupling. [A][E][I][R]
Future of space exploration The US National Research Council has set out priority goals for space research. The first is to improve the monitoring of Earth's climate and to replace current earth observation satellites that are reaching the end of their lives, so that the continuity of observation on global warming will not be broken. The second is to extend asteroid search to smaller bodies that could impact Earth, perhaps using a dedicated infrared space telescope. Third is to extend the search for life in the solar system, particularly by bringing samples of Mars back to Earth and by new missions to Titan and Europa. Fourth is to unravel how the solar system was formed, particularly by returning samples from a comet nucleus, the Moon and Venus. The fifth goal is to begin developing and testing technology for an interstellar probe to extend exploration beyond the solar system. [A][E][P][R][T][U] |
|||
| [U] Unmanned vehicles and robotics | |
||
|
|
|
|
|
Solar-powered UAV In trials at White Sands missile range, a lightweight, solar-powered plane developed by QinetiQ has broken a world record for unmanned flight by staying aloft for 54 hours. This beat the previous record of 30 hours 24 minutes by nearly a whole day. The plane, called Zephyr, has an 18 metre wingspan and weighs just 30kg. In two test flights, it reached maximum altitudes of 58,355 feet and 52,247 feet. According to QinetiQ, the results prove that an autonomous UAV can be operated on solar electric power for the duration required to provide persistent communications and earth observation in support of defence and security operations. [U][A][D][E][P][R] |
|||
| [P] Propulsion and energy | |
||
|
|
|
|
|
Ship propulsion by LNG A group of north European companies has announced plans to install a clean fuel-cell engine on board a supply ship in 2008. The full-scale test model will run on liquefied natural gas (LNG). This will cut carbon dioxide emissions by half compared to diesel engines running on marine bunker fuel and will also eliminate virtually all sulphur and nitrogen oxide emissions. Because LNG storage takes up more space, the engines are best suited to short-haul vessels in the coastal waters of regions with developed LNG infrastructure. Iceland has already announced plans to convert its entire fishing fleet to hydrogen fuel cell engines as part of its environmental drive. [P][E]
Vehicle batteries Lithium-ion batteries for use in hybrid and all-electric vehicles need to be rugged and safe, and not liable to explode or catch fire, as some lithium-ion computer batteries have done. Fire happens when a cell shorts out, gets hot, and starts a violent exothermic reaction. Most lithium-ion batteries use cobalt dioxide cathodes because these give the highest energy density - up to 0.6 kWh/kg. But something different is needed to provide the ruggedness, safety and cheapness required for vehicle batteries. A promising cathode for this is nanostructured iron phosphate. [P][M][N][T]
Hybrid vehicle energy storage Most vehicle manufacturers are concentrating on lithium-ion batteries to power hybrid cars. But ultracapacitors also have a lot of promise. A new ultracapacitor technology called Digitized Energy Storage Device (DESD) can store an energy density of 130 joules per gram. Although DESD has a capacitance-to-volume ratio that is more than 10,000 times larger than a conventional parallel-plate capacitor of the same size, the energy density is still much lower than that of lithium ion batteries. However, ultracapacitors could have a niche role alongside lithium-ion because they are better at delivering and storing energy rapidly for acceleration and breaking. Indeed, an ultracapacitor-equipped Toyota has just become the first hybrid car to win the 24-hour endurance car race held at Japan's Tokachi International Speedway. Using ultracapacitors could allow lithium-ion batteries to be optimised for maximum energy storage, life and safety rather than for maximum power output. [P][M][T]
Ultraclean combustion A gas turbine combustion technology called low swirl injector (LSI) has been tested successfully using pure hydrogen as a fuel. LSI is a mechanically simple device with no moving parts that gives a mild spin to the fuel and air mixture causing it to spread out. The flame is stabilized within the spreading flow just beyond the exit of the burner, and burns at a sufficiently low temperature that virtually no emissions of nitrogen oxides are produced. LSI also burns natural gas with virtually zero emissions. It is now being tested on syngas and hydrogen fuels in an advanced IGCC (Integrated Gasification Combined Cycle). The IGCC plant called FutureGen, is planned to be the world’s first near-zero-emissions coal power plant. [P][E]
Low-emission power stations Conventional gas-fired power stations burn methane in a stream of air. This produces a mixture of nitrogen and greenhouse gases including carbon dioxide and nitrogen oxides. Separating the gases is not practical because of the high cost and energy required. However, if methane is burned in pure oxygen, only carbon dioxide is produced. This could be used as a chemical feedstock or sequestered. Researchers at Newcastle University and Imperial College have developed and tested a pure oxygen combustion process that uses tubes of LSCF ceramic (Lanthanum-Strontium-Cobalt-Ferric Oxide) to extract the oxygen from air. The tubes look like stiff drinking straws and are permeable to oxygen ions but not to other components of air. The researchers say it should be possible to assemble a power station combustion chamber from a large number of the tubes with methane flowing through them and air circulating in the spaces between them. LSCF is resistant to corrosion or decomposition at typical power station operating temperatures of around 800 degrees C. [P][E][M]
Future of oil and gas The US National Petroleum Council has published a report called "Facing the Hard Truths About Energy" that reviews the status of global oil and natural gas until 2030. It presents a list of possible solutions for avoiding an energy crisis as well as recommendations for increased energy security. [P][D][E][T]
EPAM wave power Electroactive polymer artificial muscles (EPAMs) have great promise for actuators in future robots and other machinery. They consist essentially of several sheets of specialised rubber sandwiched between two oppositely-charged elastic electrodes. Now, researchers at SRI have shown that EPAMs can also be used to generate wave power. They have tested a prototype and estimate that a field of a thousand EPAM buoys could generate as much as a megawatt of electrical power. The output voltage is around 1 kV, which is convenient for transmitting power to land. The researchers say that an initial EPAM application is likely to be for powering navigation, communications, and sensor buoys. [P][E][I][M][R][S]
Sugar battery Sony has announced the development of a biobattery that generates electricity from sugar by using an enzyme catalyst. The battery, in the form of a cube 39 mm on each edge, has so far achieved 50 mW output. This is sufficient to power music playback on a memory-type Walkman. [P][I][J][K][V]
Nanopaper batteries Researchers at Rensselaer Polytechnic Institute have developed a flexible ultra-thin battery based on nanocomposite paper. Printed carbon nanotubes are embedded in the paper and provide the conducting electrodes. The electrolyte is soaked into the paper, and is an ionic liquid that contains no water. This means that there is nothing to freeze or evaporate, and enables the battery to operate over a wide temperature range of around 150 to -75 degrees C. The researchers say that the battery is designed for use in handheld electronics, but the light weight could also make it suitable for use in automobiles, aircraft and even boats. The paper could be moulded into different shapes. [P][A][H][I][K][N][S][V]
Cheap solar power Scientists in Israel say they have developed a solar concentrator that is sufficiently cheap and efficient to enable solar power to compete with oil and other conventional energy sources. The panel concentrates sunlight by a factor of 1000 and the light is then converted to electricity using a GaAs cell. The breakthrough is finding a concentrator design that allows really cheap manufacture. [P][J][O]
Progress on low cost solar cells In addition to exploring new methods for reducing the cost of silicon solar cells, scientists have been experimenting with alternative materials that can be processed via readily scalable colloidal chemistry techniques suitable for cheap mass production. These include other semiconductors, inorganic nanocrystals and organic polymers. Unfortunately, nanostructured materials have a lot of internal surfaces that can trap charge carriers and lead to low efficiency. Using elongated nanocrystals, long nanorods and hyperbranched crystals helps a bit, and mixing materials with different bandgaps, such as CdSe and CdTe, one can also utilise more of the Sun's spectrum. Even so, test cells currently achieve no more than a few percent efficiency and similar performance has come from coated ZnO nanowires. Other researchers are using organic nanomaterials based on blends of semiconducting polymers and fullerene derivatives. These have so far given efficiencies of up to 4 to 5 percent. [P][E][J][M][N][O][T]
Biofuel issues A paper by the UK Parliamentary Office of Science and Technology examines the issues relating to current and future transport biofuels. Biofuels can provide carbon savings but current 'first generation biofuels' are controversial because of concern over their environmental and socio-economic impacts, especially in developing countries. [P][D][E][M][T][X] |
|||
| [M] Materials, structures and surfaces | |
||
|
|
|
|
|
Recyclable hydrogen source According to researchers at Purdue, aluminium-gallium and water could be used as fuel for hydrogen-powered vehicles, avoiding the need to transport and store hydrogen itself. The hydrogen is produced on demand by adding water to the aluminium-gallium. Normally water does not react with aluminium because it cannot penetrate through its tough skin of alumina. However, gallium hinders the formation of this skin. The researchers say the spent alumina can be converted back to aluminium cheaply enough for the fuel to be cost-competitive with gasoline. The gallium is recycled, and because impure gallium can be used, the overall cost of the gallium should be viable. The technology might initially be used in applications where it would be very difficult to handle hydrogen fuel directly, such as lawn mowers and submarines. [M][P][U]
Recyclable hydrogen source A litre of ammonia borane (AB) weighs about 0.75 kg and can hold up to 1800 litres of hydrogen. This makes AB a promising material for storing hydrogen for vehicle propulsion. Scientists are now learning to manipulate the release of hydrogen from small pellets of AB at predictable rates. The pellets are refuelled by chemically recycling them back to AB in a chemical plant. [M][P]
Superior lubricant Researchers at Argonne National Laboratory have found that adding nanoparticles of boric acid to motor oil greatly reduces engine friction. They believe this should give a 4 to 5 percent improvement in fuel consumption, as well increasing engine life. Substituting boric acid for sulphur-containing additives would also avoid sulphur emissions that are bad for the catalytic converter as well as the environment. [M][P]
Superconducting ferromagnet A material that is both superconducting and ferromagnetic at normal pressure has been devised from the elements uranium, cobalt, and germanium by physicists from the University of Amsterdam and the University of Karlsruhe. Normally the strong magnetic fields in a ferromagnet would break up the pairing of electrons with opposite spins that produces superconductivity. But in the superconducting ferromagnet the paired electrons have their spin in the same direction rather than opposite. [M]
Tuning magnetism Hard magnets in which magnetic domain walls are firmly pinned are used for permanent magnets. Soft magnets in which domain walls easily move are used in motors and transformers because they adapt to alternating current and dissipate much less energy. An international research team, led by scientists at the London Centre for Nanotechnology (LCN), has now a found a way to switch a material’s magnetic properties from ‘hard’ to ‘soft’ and back again, enabling the material to be switched or "tuned" to the application. This could lead to new ways of controlling electromagnetic devices. [M][J][N][O]
Strength of bone Understanding how bone achieves its remarkable toughness could enable materials scientists to design new lightweight structural materials. Bone's toughness is due to a number of different strength mechanisms at different scales. Research at MIT has now clarified how some of these mechanisms work together. The mineralized collagen fibrils in bone are made up of strings of alternating collagen molecules and consistently sized hydroxyapatite crystals. These strings are “stacked” together in a staggered fashion such that the crystals appear in stair-step configurations. Weak bonds form between the crystals and molecules both in the strings and between the strings. When pressure is applied to the fabric-like fibrils, some of the weak bonds break, creating small gaps or stretched areas in the fibrils. This spreads the pressure over a broader area and protects other, stronger bonds within the collagen molecule itself, which might break outright if all the pressure were focused on them. The stretching also lets the tiny crystals shift position in response to the force, rather than shatter. [M][H][N]
Aluminium nanocomposite A new high-strength material consisting of ultrafine nanograins of aluminium has been made by researchers at the University of Melbourne. The material has a strength of up to 740?MPa and a Vickers microhardness of 2285?MPa, and it is also very stable at temperatures of up to 400? degrees C. This means it may be suitable for high-temperature applications in aerospace and automobiles. [M][N][P]
Mechanical properties of very thin films A new and simple way to determine the mechanical properties of very thin films has been unveiled by an international team of researchers. The technique involves studying the wrinkles that are created in the film when a drop of water is placed on it. By counting the number of wrinkles and measuring their lengths, the thickness and elasticity of the film can be determined to about the same accuracy as much more sophisticated methods such as X-ray reflectivity. [M][S]
Simulated microgravity growth To determine the precise structure of a protein by x-ray crystallography required using large pure protein crystals. Unfortunately, convection currents produced as a protein crystal is grown from solution cause defects. This can be prevented by growing crystals in the microgravity of the International Space Station. But scientists from the Netherlands and Japan have now shown that magnetic levitation can mimic the effects of microgravity. This requires a magnet that can produce fields of around 33 Tesla for long enough to grow large protein crystals, but the method should nevertheless provide a much cheaper, faster and better controlled way to produce crystals of the same quality as those grown aboard the ISS. The levitation exploits the fact that diamagnetic materials - including most organic materials - are repelled by very strong magnetic fields as a result of changes in the orbital motion of their electrons. [M][A][G][H][N][O]
Super crystal semiconductors University of Arizona physicists have discovered that "super crystals" exist in certain organic semiconducting solids. In super crystals, not only do the patterns of atoms or molecules repeat, but also there is a much larger periodically repeating super-structure of plane traps for electrons, called soliton walls. Super crystal semiconductors may have important applications: they conduct electricity in novels ways and the super-crystal period and electronic properties might be tuned by an external magnetic field. [M][J][N][O]
Antifreeze paint Antifreeze proteins found in plants, fish and insects, have previously been synthesised in the lab and used to prevent foods from being damaged by icing up in the refrigerator. Now Fraunhofer researchers have succeeded in incorporating antifreeze proteins into a coating that, if the technology can be scale up, could prevent ice from forming on the wings of aircraft. It could also prevent ice from dragging down power cables or be applied to food freezers to prevent them from icing up. [M][A][P] |
|||
| [E] Environment, transport and marine | |
||
|
|
|
|
|
Coral reef decline Coral reefs in the Indo-Pacific are disappearing twice as fast as tropical rainforests, according to the first comprehensive survey of coral reefs in this region, which holds 75 percent of the world's reefs. Researchers at the University of North Carolina compiled data from 6000 studies that between them tracked the fate of 2600 reefs in the Indo-Pacific between 1968 and 2004. In the early 1980s about 40 percent of reefs were covered with live coral, but that number had halved by 2003. Today only 2 percent of Indo-Pacific reefs have the same amount of live coral as they did in the 1980s. The survey found little difference between protected and unprotected reefs. Though well-managed reefs are definitely doing better in terms of fish population, they are not faring better in terms of coral cover. [E][X]
Irrigation masks global warming The effect of global warming on crop yields has been masked by increased use of irrigation, which produces cooling because of greater water evaporation. According to research at Lawrence Livermore, in the highly irrigated regions of California's San Joaquin Valley, evaporation has reduced daytime temperatures by 1.8 to 3.2 degrees C compared to areas with low levels of irrigation. Around 40 percent of the world's food is now grown using irrigation. But scarcity of water will limit future expansion and even lead to less irrigation in some areas. As a result, it is unlikely that irrigation can continue to curb the future rise in temperature. [E][D]
Origin of ice ages Analysing the ratio of oxygen and nitrogen trapped in Antarctic ice cores has enabled researchers at Scripps Institute to determine how much sunlight fell on Antarctica in summers going back 360,000 years. They found that the variation correlated with changes in the Earth's orbit round the Sun and with the onsets and terminations of the last four great ice age cycles. The results confirm that these ice ages began when Earth’s distance from the Sun during its annual orbit became great enough to prevent summertime melts of glacial ice, allowing a progressive build up of ice. At the end of each ice age cycle, the effect of the changes in Earth’s orbit were amplified through a series of steps in which warming led to more carbon dioxide being released from the oceans into the air and causing further warming through the greenhouse effect. [E]
Atlantic salinity Salinity data gathered by fisheries, navy and research ships travelling across the North Atlantic between 1955 and 2006 suggest that the surface waters are becoming saltier. This is probably due to global warming heating the ocean and increasing evaporation. The greater salinity should be helping, at least in the short term, to prevent global warming disrupting the Arctic thermohaline circulation and weakening the global ocean conveyor. [E]
Ocean circulation The Permian mass extinction 250 million years ago, in which over 90 percent of marine species became extinct, probably involved global warming that halted the ocean currents, causing the oceans to become stagnant and devoid of oxygen. Climate models suggest that carbon dioxide levels today are still nowhere near causing a similar collapse. But it is nevertheless important to monitor what is happening. Last year a UK-led team published evidence that the Atlantic circulation may have weakened by about 30 percent over half a century. But this was based on historical records from just five sampling expeditions and could reflect natural variations. The same team has now produced the first detailed picture of the natural variations by using instruments strung out across the Atlantic to measure water flows comprehensively for over a year. This has revealed that the circulation varied by a factor of eight over the year. It means that continuous monitoring over many years will be needed to separate natural variation from any effects of global warming. [E][R][X]
Tasmanian connection Scientists at CSIRO have identified the missing deep ocean pathway (supergyre) south of Tasmania that connects the three Southern Hemisphere ocean basins. Locating this missing component of the thermohaline circulation (or global ocean conveyor) will help in understanding how the oceans affect global climate. The findings show that this Tasmanian connection current forms a choke point linking the major circulation cells in the Southern Hemisphere oceans. Monitoring changes in flow through this choke point may provide an important indicator of the state of the global climate system. [E][R]
Decadal Climate Prediction Scientists at the Hadley Centre say they have developed a climate model that includes short-term natural events, such as El Nino. This means it can predict how ocean currents, as well as human activities, will affect temperatures over the next decade. Average global temperatures have been relatively flat in recent years because of natural climate variations, but the model predicts they will start rising again soon and temperatures are likely to exceed current records in at least half of the years between 2009 and 2014. The predictions are possible because of recent improvements in understanding how ocean dynamics influence the climate system. A network of automated ocean-going devices, now numbering around 3,000, has been deployed around the planet since 1999. These devices, known as Argo floats, provide updates on ocean temperature and salinity - factors that are critical in determining global climate patterns. [E][C][R]
Predicting winter severity Scientists have verified the accuracy of a model that uses October snow cover in Siberia to predict upcoming winter temperatures and snowfall for the high- and mid-latitudes of the Northern Hemisphere. The model was verified by analysing seven real-time winter forecasts and 33 winter hindcasts (simulations of winters going back to 1972). October is the month when the Siberian high pressure area forms. In years when Siberian snow starts piling up more strongly, a strong Siberian high develops with colder autumn temperatures across Northern Eurasia. This produces stratospheric warming in January, bringing a warmer winter in the high latitudes but colder weather in mid-latitudes. [E][C][P][R]
Increasing rainfall NASA scientists have detected the first signs that tropical rainfall is on the rise. They used a 27-year global record of rainfall from satellite and ground-based instruments - the longest and most complete data record available. This showed that the rainiest years between 1979 and 2005 occurred primarily after 2001. The wettest year was 2005, followed by 2004, 2003, 2002 and 1998. The rainfall increase was concentrated over tropical oceans, with a slight decline over land. Across the whole planet, the total amount of rain falling has changed very little. But in the tropics, where nearly two-thirds of all rain falls, there has been an increase of 5 percent. Global warming is considered the most likely cause. [E][R] |
|||
| [R] Remote sensing and sensor systems | |
||
|
|
|
|
|
Drizzle radar Delft University has installed a new weather radar that provides highly accurate measurements of cloud droplets and even the lightest of rainfalls. The radar will help researchers to determine cloud life cycles and their relationship to radiation and airborne dust. This is poorly understood at present but of great importance to climate models. [R][E][P]
Space-based seismic monitoring The Gravity Recovery and Climate Change Experiment (GRACE) consists of two Earth-orbiting satellites whose relative spacing changes in response to gravitational effects. It can monitor changes in terrestrial water storage and polar ice melting, and is a key sensor for tracking the effects of climate change. Researchers have now also shown that GRACE can monitor the seismic deformations produced in the Earth during and after a major earthquake. [R]
Imperfect cloaking Perfect invisibility cloaking is very difficult to achieve, but imperfect cloaking can still render an objective invisible to a monostatic radar, according to scientists from Zhejiang University and MIT. For monostatic detection, no reflection wave will be received by the detector if the imperfect cloak has an impedance matched with free space. [R][M][O]
3D imaging of the cell A new imaging technique developed at MIT has allowed scientists to create the first 3D images of a living cell without the need for fluorescent markers or other externally added contrast agents. The method uses interferometry to produce 2D images of the variations in refractive index in the cell. A hundred images, each taken from a different direction, are then combined to produce the 3D image. This is similar to the way that x-ray CAT scans produce 3D images inside the body by combining 2D x-ray images from multiple angles. The current resolution is about 500 nm, but the researchers expect to achieve 150 nm or better. [R][B][G][H][N]
Femtosecond imaging Researchers have used the ultrafast X-ray pulses from a free-electron laser to image the explosion of a nanoscale object in just a femtosecond. The technique is a new form of X-ray holography. The holographic pattern reveals the structure of the sample’s material and how it evolved during the explosion. The achievement is a step towards being able to observe simultaneously how all the atoms in a molecule move. [R][N][O][S] |
|||
| [S] Sensor devices | |
||
|
|
|
|
|
Atomic force microscopy A new atomic force microscope (AFM) that can measure the mechanical properties of a material a thousand times faster than conventional AFMs and with a hundred times less pressure has been developed by researchers in the US. This vast improvement results simply from placing the AFM tip at the corner of the AFM's cantilever beam, rather than at the centre as usual. When the tip hits the surface being profiled, the cantilever experiences a torque, which causes twisting-like vibrations that can easily be measured. [S][N]
Nanoparticle hydrogen peroxide sensor Hydrogen peroxide is thought to be over-produced by cells at the early stages of most diseases. But there has been no imaging technique available to capture this process in the body. Now, researchers at Georgia Tech and Emory University have created a nanoparticle that can detect trace amounts of hydrogen peroxide in animals. They say the particles have incredible sensitivity and can detect nanomolar concentrations of hydrogen peroxide. The nanoparticles are made of peroxalate esters and are believed to be totally nontoxic. A fluorescent dye (pentacene) is encapsulated into the polymer and when the nanoparticles bump into hydrogen peroxide, the dye is excited and emits light. The hope is that the nanoparticles, injected into the body, could provide an all-purpose diagnostic tool to detect the earliest stages of any disease that involves chronic inflammation, including cancer, Alzheimer’s, heart disease and arthritis. [S][H][N][R]
Vehicle pollution sensor It may soon be possible for drivers to monitor their vehicle's pollutant emissions as they are driving. Scientists at the University of Manchester have created a sensor that uses lasers to measure levels of carbon dioxide, carbon monoxide and methane from directly inside the exhaust. [S][E][O][P]
Portable laser spectrometers Scientists in Sweden have demonstrated a compact mirrorless optical parametric oscillator (OPO) that, when combined with a laser, can generate a wide range of wavelengths that standard lasers cannot achieve on their own. The key to the new OPO is its potassium-titanyl phosphate crystal and its design, which amplifies the laser light itself, eliminating the need for mirrors, and also allows fining tuning of the output wavelength. The device could lead to compact portable spectrometers with wavelengths suitable for detecting explosives or biological and chemical weapons. [S][O][R]
Opaque lens focusing Physicists at the University of Twente report that they have managed to use scattering in opaque materials to focus the light to an intensified point. The technique uses an LCD to spatially modulate the wavefront of the light beam before it arrives at the sample. The spatial modulation is adjusted by computer to maximise the intensity of the light transmitted through the sample. The researchers found that using the strong scattering from titanium dioxide pigment they could intensify the beam more than a thousand times. They hope that scanning such an intense beam over a biological sample can image it in a similar manner to a scanning electron microscope. [S][N][O][R] |
|||
| [O] Optoelectronics, optics and lasers | |
||
|
|
|
|
|
TeraHertz sources Research at the University of Augsburg predicts theoretically that graphene can act as a non-linear frequency multiplier to convert microwave radiation to frequencies above 100 GHz and into the teraHertz range, where good radiation sources do not exist. [O][N][R][S]
Mode-locked silicon laser Researchers at UCSB have built the world's first mode-locked silicon evanescent laser, a significant step toward combining lasers and other key optical components with the existing electronic capabilities in silicon. The device can emit 40 billion laser pulses per second. The ability of mode-locked evanescent lasers to deliver stable short pulses of light is useful for applications such as high-speed data transmission, multiple wavelength generation, remote sensing (LIDAR) and highly accurate optical clocks. [O][I][J][R]
Femtosecond optoelectronics Ultrafast optoelectronics may be possible by using the electromagnetic fields of femtosecond laser pulses to induce and reverse tiny electrical currents along molecular wires, according to Canadian researchers. They propose shining pulses with two different frequencies onto a polyacetylene molecule. [O][N]
Watching coherence collapse Researchers at the Ecole Normale Supérieure in Paris have developed a new technique that enable them to watch, for the first time, the step-by-step collapse of a coherent light field. Their system is a box lined with superconducting mirrors, which can keep photons from a coherent microwave field bouncing around inside for a fraction of a second. Before measurement, the system is in a superposition of several different photon numbers. Individual atoms are sent in to interact with the field’s photons without destroying any of them. Electrons in these atoms oscillate between two excited states, and the rate of the oscillation is governed by the photon number, giving a measure of the number of photons in the box. Initially this number fluctuates but after many measurements the cumulative distribution begins to centre on a particular number, revealing that the system is collapsing into a well-defined state. [O][C][S]
Quantum levitation The Casimir effect normally causes an attractive force between two plates when they are less than a micron apart. But by inserting a metamaterials with negative index of refraction between the plates or alternatively by manipulating the strength of the Casimir force by increasing the reflectivity of one of the plates, researchers believe it may be possible to make the net force repulsive and to achieve quantum levitation. [O][N]
Nuclear antenna Upcoming x-ray free electron laser (FEL) facilities may produce sufficiently intense radiation that the successive absorption by a nucleus of thousands of x-ray photons could generate an electron-positron pair. It is proposed theoretically that the pair might then act like an antenna and absorb even more photons, converting into a pair of muons. This would be like having an electron-positron collider the size of an atom. [O][P]
Ultrafast all-optical magnetic memory Physicists in the Netherlands and Japan have shown they can flip a magnetic memory bit by firing a very short pulse of circularly-polarized laser light at it. No external magnetic field was required to flip the bit, and as a result its value could be changed about 50 thousand times faster than the fastest conventional magnetic memory. The result could in principle lead to the development of low-cost and ultrafast all-optical magnetic hard disk drives, if suitable lasers and optics could be made sufficiently small and cheap. [O][C][M][N]
Photonic memory Physicists at the Weizmann Institute have shown that 2D images of light can be shone into a gas of room-temperature rubidium-87 atoms, stored there and then retrieved up to 9 microseconds later. This delay, which is limited by the diffusion of the rubidium atoms, is almost a thousand times longer than the previous record. The researchers have achieved storage times of 30 microseconds using phase shifting techniques that are insensitive to the diffusion. The researchers believe they can store 3D images and that this 3D system would have enough capacity to be used as a memory device for photon states used in quantum computing. [O][C]
Holographic memory By using lasers to etch data onto the microbial protein bacteriorhodopsin, researchers at the University of Connecticut may have demonstrated a way to produce rewritable holographic memory. Holographic memory stores data in three dimensions instead of two and could make data retrieval hundreds of times faster. [O][C][G][N] |
|||
| [I] IT, communications, networking and secure systems | |
||
|
|
|
|
|
Silicon photonics comms Silicon photonics is now reaching the market place in the form of a silicon-based optical fibre cable. The cable can transmit data at 40 Gbits/sec, suitable for high-performance computer centres and data centres. Each end of the cable has a silicon CMOS chip that contains both a transmitter and a receiver. The transmitter contains a relatively cheap indium-phosphide laser, whose light is split into four beams that each pass through a 10 Gbit/sec silicon modulator. Then a silicon holographic lens, lithographically etched into the surface of the chip, launches the modulated light into low-cost optical fibre. At the other end of the fibre the light passes through another holographic lens and is directed onto an array of indium-phosphide-based photodetectors, which convert it back into an electrical signal. The CMOS chip amplifies and cleans up the signal and sends it to an electrical receiver. [I][C][J][O]
Spectrum management Demand for radio spectrum is increasing with the rise in wireless and mobile services. A paper by the UK Parliamentary Office of Science and Technology examines current spectrum management issues. These include more liberalised spectrum use, European and global harmonisation, and Administered Incentive Pricing and its application to spectrum held by the UK MOD, Civil Aviation Authority and Broadcasters. The paper also discusses the options for using the spectrum in the range 470 - 862 MHz that will be freed as analogue TV is switched over to digital TV. [I][T]
Automatic wireless penetration testing A point-and-click computer program that can automatically hack into vulnerable wireless networks, or probe them for weak spots, has been released by US researchers. It combines a number of different tools in an easy to use package and is aimed making it easy for administrators to test that wireless networks are configured securely. The tool automatically searches for wireless local area networks within range, probes them for specific vulnerabilities, and calls up the tools necessary to do test penetration. The down side is that integrated penetration tools also make it easier for criminals to attack wireless systems. [I]
Tackling e-crime A report on e-crime by the UK House of Lords has recommended that more government action is needed to protect internet users. The report says the UK government should work with the EU to see if more legal responsibility for security could be handed over to internet companies and software makers. It also suggests that a network of police computer laboratories be set up to fight the "flourishing" online crime industry and that a central system for reporting of e-crime should be established so that the threat is better understood. Banks and other companies trading online should be required by law to notify this central authority whenever they suffer a breach. The report also recommends that resources available to the police and criminal justice system to catch and prosecute e-criminals need to be increased. [I][D]
Secure electronic voting Voting systems have to meet myriad requirements: guarding the secrecy and anonymity of each voter, preventing anyone tampering with the results, being verifiably accurate and simple enough to be used with minimal training by poll workers who are not technically expert. They must also be error-limiting so that it is difficult for voters to do things they do not intend, and they must be sufficiently cheap. First generation systems had many problems and even now it is hard to make systems fully proof against accidental or deliberate software errors, multiple voting or inserting of malicious code. The answer may be to adopt a hybrid approach using optical scanning of paper votes that can then be counted by machine but are also kept for recount if necessary. [I][C][O][Q]
Cyber profiles and privacy In response to growing concerns about cyber privacy, the top four search sites, Google, Microsoft, Yahoo and Ask, have unveiled plans to cut how much data they collect and hold about individuals' online searches and how long they store the data. There is also concern that people using social networking sites could be vulnerable to identity theft. Various personal search websites are making it progressively easier to find friends and colleagues online. But the ability to trawl social networking sites and other internet information and build up a detailed profile of an individual person is also a threat to them. [I][K] |
|||
| [K] Knowledge, information and technology management | |
||
|
|
|
|
|
Small world Innovation networking When companies are indirectly linked in a network of strategic relationships with only a few degrees of separation, they are more innovative, according to researchers at the University of Washington and New York University, who analyzed the innovative performance (measured from patents) of 1,106 companies in 11 different industries over a six-year period. They found that companies reap greater benefits when they are part of a network that exhibits a high degree of clustering and only a few degrees of separation, both of which are characteristic of a small world network. The clustering enables information to travel quickly and accurately because it creates redundant paths between companies and increases the level of cooperation among them. This makes firms more willing and able to exchange information and makes information exchange more meaningful and useful. A network in which companies are directly or indirectly connected to many others makes a large amount and diversity of information available and this adds to innovation. [K][W][X]
Connecting employees and knowledge A McKinsey web article discusses the importance of connecting employees and integrating their knowledge. The article is focused on investment banks, but its recommendations are applicable to any complex knowledge-intensive business. Increasing complexity of products demands greater specialization and has fostered deep silos. In complex organisations it is hard to grasp what is possible and for people to know others even in their own silo. Relentless focus on accountability and short-term earnings of business units has “sealed” the silos, crowding out time for cooperation among them. The article argues that far from trying to blow up silos, organisations should use quantitative methods to map the informal networks among their employees, use deep-dive interviews to investigate opportunities for collaboration, and ruthlessly focus on the economics. Only those interactions that add value should be fostered. In pursuing cooperation among business units, the top team needs to be closely aligned. Initiatives need to be introduced to develop organization-wide people, knowledge and capabilities, and effort concentrated on a handful of cross-cutting themes. [K][H][I][T][W][X]
Product networks and national prosperity Analysis of the connections among different types of economic activities explains why some countries succeed, and others fail, in diversifying their economies. Traditionally, economists have tried to link a country's commercial expansion to "factors of production," such as reliable transportation infrastructure or the availability of skilled and unskilled labour. But new research has found that close relationships between products is more important and that a country's competitive edge can spread from one kind of product to another related product along a well-defined network of links, much as disease epidemics tend to spread among people who are socially connected. The researchers have produced maps of products and how they are linked. These could help countries design good policies by indicating the most promising paths to creating new industries. The network's structure also shows why those developing countries that specialise in products at the network's periphery, such as oil, minerals, cereals, and coffee, are less economically successful. [K][W][X]
Standardising scientific reporting Vast amounts of research are being conducted in the fields of genomics and proteomics. But often published results are difficult to interpret or use because of variations in format or because key information is missing. To address this problem, new minimum reporting standards have been developed by two international groups of scientists. The aim is to suitably standardise the content of reports worldwide whilst at the same time keeping the guidelines sufficient simple that they are not too burdensome. [K][G]
Dissemination of science A website, SciVee - dubbed the YouTube for scientists - has been launched with backing from the Public Library of Science (PLoS), the US National Science Foundation (NSF) and the San Diego Supercomputer Center (SDSC). Its purpose is to improve the dissemination and comprehension of science. It allows scientists to upload published papers, as well as a podcast presenting the paper. A proprietary new technology synchronizes the text of a paper to a video of the author explaining its key findings. SciVee also provides ten minute video summaries in which the author describes findings in greater detail than an abstract. The hope is that SciVee will develop into a wide-ranging bridge between scientific communities and that its dynamic form of presentation could also encourage a lay audience to investigate science and help motivate young people to follow scientific careers. [K][I][V]
Google Sky Google has added a new feature called Sky to Google Earth. This adds a wealth of astronomical data, including images of more than 100 million individual stars and 200 million galaxies. Users can pick out particular stars or planets manually, or using the search field, and zoom upwards to see more detailed images and additional information. Some 20,000 celestial objects can be searched for by name using the Sky feature. Astronomical imagery and information comes from a number of scientific organisations, and institutions are populating Sky with the most recently discovered heavenly objects. [K][A][R][V]
Compiling geospatial data In a geospatial project almost all the effort is devoted to hunting down usable data. The data, when they exist at all, often are archived in incompatible formats, have varying degrees of accuracy and precision, and sometimes require a good deal of political savvy to find. To overcome this problem, the architects of the Global Earth Observation System of Systems (GEOSS) are compiling what is essentially a search engine for environmental data, including not just data from Earth-observing satellites but also terrestrial sensor data, population figures, and regional health and ecosystem information. [K][D][E][H][R][X]
Chemoinformatics In the case of new infectious threats - from new diseases, antibiotic resistance or biowarfare - there might be no time to develop a completely new drug ab initio. However, advances in chemoinformatics may provide a solution by enabling existing drugs to be repurposed, according to researchers at the University of British Columbia. Chemoinformatics involves identifying vulnerable cellular components of a pathogen using proteomics and then using computer search and optimisation to identify existing drugs that have good potential for activity against the target. Many drugs that are not used as antibiotics nevertheless have antibiotic capabilities. [K][C][D][G][H][N][W] |
|||
| [C] Computing, supercomputing, modelling and simulation | |
||
|
|
|
|
|
Grids and e-Science Progress in e-science and Grid computing is reviewed in a paper by the UK Parliamentary Office of Science and Technology. The paper covers the expanding use of Grids and issues of regulation, security, standards, licensing, protection and accessibility of data, and ease of use. [C][I][K][T][V][W]
Marking exams by computer Software is being developed to enable exams in English comprehension to be marked by computer. The exam scripts are scanned into the computer. The software then converts the handwriting text into computer text, a task helped by the fact that children generally have a smaller vocabulary and better formed handwriting than adults. The software then scores the text by looking for important features. Some of the features are content dependent - key phrases or words in the answer. Other features are content independent, such as the length of the sentences and the total answer length. The computer was first trained on a sample of scripts that had been marked by human examiners. For English comprehension the important features are fairly well defined, and in trials the software was within a grade of the human examiners 70 percent of the time. The software cannot yet tackle an answer to a more ambiguous exam question. [C][K][U][V]
Quantum dot approach to quantum computing The September issue of IEEE Spectrum has a review of the quantum dot approach to quantum computing. The advantage of this approach is that it should be easy to fabricate large arrays of miniature electronic devices that can be individually addressed and interconnected. The concept is that the core of the machine will consist of a single chip carrying dozens, hundreds or perhaps thousands of quantum dots, each holding one electron. The chip will sit inside an ultracold dilution refrigerator encircled by a superconducting magnet. All of the essential ingredients have now been realized. The next steps are to integrate the basic functions into a single system, to expand the system from two quantum dots to a large array of dots, and to find a way to substantially increase the coherence time and to detect and control entanglement. [C][J][T]
Fine grain climate modelling In order to protect against climate change, one must be able to forecast fairly precisely where temperature, drought, and flooding are likely to be most serious. This required local modelling on a substantially finer scale than is available in current global climate models. Producing such local models for countries and areas that are most threatened by global warming, such as Bangladesh, can help in designing flood defences and early warning systems that are likely to have the best effect. [C][D][E][R][W][X] |
|||
| [W] Whole life engineering, manufacture and testing | |
||
|
|
|
|
|
Standards and agile design A feature article in the September issue of IEEE Computer describes the evolution of software standards, the relationship between process and agile approaches to software engineering, and how standards contribute to agility. [W][C][K]
Structural design for fire safety The events of 9/11 highlighted the danger that fire poses for the stability of structures and the need to design buildings that maintain integrity when they are ablaze. Larger furnace facilities are enabling materials and structures to be tested more realistically. And researchers are also developing more powerful computer simulations of how specific structures would perform in fires. [W][C][M][T]
Chiral drug manufacture Most drug molecules are chiral, meaning they come in both left-handed and right-handed versions (called enantiomers). However, all lifeforms on Earth are homochiral: they exclusively use right-handed sugars and left-handed amino acids. If a drug has the wrong handedness it can have disastrous effects: thalidomide is a notorious example. To avoid the cost of getting regulatory approval for both enantiomers of a chiral drug, pharmaceutical companies generally produce just the single enantiomer they want. But doing this with extremely high purity and on a large scale is difficult. One approach is to produce both enantiomers and then to separate them out. Another is to find methods of asymmetric synthesis that produce only the desired enantiomer. This generally involves catalysis and asymmetric hydrogenation, and assembling the drug from appropriate homochiral building blocks. [W][H][M][N][T]
Quality in drug manufacture According to a McKinsey study, drug and medical-product manufacturers tend to trail companies in other industries in measuring and controlling product quality. By adopting world-class manufacturing processes they could reduce their production costs and the risk of regulatory fines. Some companies are doing this, but others hesitate to change, claiming that strict regulation makes changes far too costly and complicated. [W][H][M][T] |
|||
| [X] Systems, complexity and risk | |
||
|
|
|
|
|
Detecting order in dynamical systems Researchers at the University of Warwick report they have found a powerful way to detect precisely when ordered patterns form in a previously disordered dynamical system. They say the method is much more accurate than the normal statistical analysis of dynamic systems and it should be particularly good at picking up the “phase transitions” from disorder to order in complex systems. They tested it on a model of flocking behaviour of large numbers of bacteria, birds or insects, and found it was four times better than conventional methods. They say it is widely applicable to dynamical systems, not only to flocking but to systems like plasma in the solar wind and fusion reactors or to crowds of people. It could even be used to find unusual patterns in stock market behaviour, uncovering new and unexpected market connections and mutual dependencies between companies. The method uses an information theory tool that measures mutual information - the mutual dependence between variables. This can detect patterns and correlations from a very small set of points (typically 10 within a large system). [X][C][K]
Self-organising reproducing systems Dust grains in a plasma can pick up a negative charge by absorbing electrons from the plasma. Each charged grain then attracts a surrounding shell of positive ions. The grains can also self-organise into regular arrays called plasma crystals, and researchers have previously found that these crystals can be in the form of spiral structures. Now computer simulations by researchers at Max Planck suggest that electrically charged dust can organise itself into DNA-like double helixes that behave in many ways like living organisms, reproducing and passing on information to one another. Such reproducing plasma crystals might conceivably exist in Saturn's rings, where the 'dust' would actually be fine ice grains, and the nourishing plasma would be supplied by the solar wind. [X][A][G]
Managing cultural change Achieving goals relating to educational attainment, social mobility, equal opportunity, healthy living, environmental sustainability, carbon emissions and thriving communities depends strongly on managing cultural change. The UK Cabinet Office has published a discussion paper that reviews the state of knowledge about culture change and sets out a practical step-by-step approach to implementing culture change policy. It looks at how behaviours can be influenced by factors such as incentives, regulation, legislation, barriers, community action, social pressure and marketing techniques, and by the levels of information and awareness there is about different choices or courses of action. As examples, the paper applies the culture change framework to case studies from education and healthy living. [X][D][E][H][K][P][W] |
|||
| [V] Virtuality and human-machine interface | |
||
|
|
|
|
|
Virtual worlds Social scientists are getting insights into real life by studying what people do in virtual worlds such as World of Warcraft and Second Life, using these as virtual laboratories. Second Life allows social scientists to build their own objects to test the reactions and responses of gamers. And, the conflict in World of Warcraft gives insights, for example, on how individuals can be induced to cooperate in producing public goods. The games could enable scientists to carry out large-scale studies, for example of alternative governmental regimes, that would be impossible in society at large. [V][C][D][E][K][X]
Virtual worlds Second Life is reported to now have a population of over 9 million residents and millions of dollars change hands there every month. Companies including IBM are predicting that this is the start of a major transformation in how people interact on the Web, moving from a flat screen to an immersive experience. At present people shop on the internet in much the same way that they use a catalogue or brochure. In the future people may instead use virtual shops like they currently use real shops. [V][I][K]
High dynamic range displays The next improvement in display technology beyond high definition could be high dynamic range (HDR). On an HDR display, the brightest whites are hundreds of thousands of times brighter than the darkest blacks. This makes images appear more realistic. Researchers say that HDR does not need the same increase in bandwidth that has slowed the introduction of high-definition television. Low dynamic range data can be converted into high dynamic range using simple software that stretches the dynamic scale. [V][O]
Photonic crystal display The first full-colour display made from a single material has been developed by researchers at the University of Toronto, who say the technology could be commercially available in as little as two years. The pixels in the device are made from photonic crystals similar in structure to opal. Each crystal is made from silica microspheres in a repeating 3D pattern which blocks certain colours whilst reflecting others. Stretching the material alters the colour of the pixel by changing the spacing between the microspheres. In this way the device can produce the whole spectrum of colours, even ultraviolet and infrared light, using only incident light. This means no colour filters are needed and the display can be viewed as well in bright sunlight as in indoor light. The stretching is controlled by the voltage applied to an electroactive polymer to which the crystals are bonded. [V][O]
New touch screen technology Touch screen functions are becoming indispensable on displays for mobile devices. Usually the touch function is provided by a film bonded on top of the LCD panel. But this reduces image quality and increases the thickness. To remove the need for the film, Sharp has now developed a touch-screen LCD that has an optical sensor built into each pixel. This means that the display can also be used as a scanner. The display can recognise when it is simultaneously touched with two or more fingers, allowing more complex multifinger commands to be used. [V]
Out-of-body experiences recreated Using virtual reality goggles to mix up the sensory signals reaching the brain, researchers at UCL and the Swiss Federal Institute of Technology have found a way to trigger an out-of-body experience in healthy volunteers by tricking their brain into thinking their body was located elsewhere. The visual illusion plus the feel of their real bodies being touched made volunteers sense that they had moved outside of their physical bodies. The results suggest that natural out-of-body experiences may occur because of a disconnect between the brain circuits that process visual and tactile information. The researchers also say their findings could have practical applications, such as helping take video games to the next level of virtuality so the players feel as if they are actually inside the game. Or, surgeons might also be able to perform operations on patients thousands of miles away by controlling a robotic virtual self. [V][B]
Testing cognitive performance When people are doing tasks where an error can have grave consequences, it is important to ensure that their cognitive performance is not impaired by stress, fatigue or lack of sleep, or by alcohol or drugs. Tests exist for assessing cognitive performance, but these are quite lengthy and have the problem that people learn to do them better over time. Now, researchers at the University of Pennsylvania working with NASA have developed a handheld device that takes only 3 minutes to test vigilance. It involves pressing a button as quickly as possible after a light flashes. It measures concentration and speed of response, and the researchers say that people do not get better at taking the test over time. [V][A][B][D][H] |
|||
| [B] Brain research and human science | |
||
|
|
|
|
|
Avian intelligence New Caledonian crows, famed for their tool-making skills, can also use tools to manipulate other tools, according to research at the University of Auckland. Such “metatool” use is usually only seen in humans and apes. The researchers believe the crows are probably using "analogical reasoning", applying previous experience – tool gets food - to solve a novel, but structurally similar problem – tool gets tool gets food. Evidence for such analogical reasoning has also been found by researchers at the University of Cambridge in the food-hiding behaviour of birds closely related to the crows. [B][K]
Gender-specific behaviour For years, scientists have searched in vain to identify what parts of the brain drive the dramatic differences between male and female behaviour in animals. Now biologists at Harvard University have discovered that the epicentre of sex-specific behaviour in many species may not lie in the brain at all but may be a small sensory organ known as the vomeronasal organ. This sensory organ is found in the noses of all terrestrial vertebrates except higher primates including humans. The researchers found that defects in this organ cause female mice to adopt male behaviours and to abandon female behaviours such as nesting and nursing. [B]
Self-control UCL researchers have used fMRI to identify the area of the brain responsible for self-control, where the decision not to do something occurs after thinking about doing it. They showed that this area is separate from the part of the brain associated with taking action. From the strength of activity in this area it is also possible to distinguish individuals who tend to be cautious from those who tend to be impulsive. [B]
Threat response and anxiety Using fMRI, researchers at UCL have identified how the brain responds to a threat. They found that when a threat is distant, the associated brain activity is concentrated in the ventromedial prefrontal cortex, a brain area just behind the eyebrows that responds to anxiety and helps control strategies on how to respond to the threat. However, as the threat comes nearer, brain activity shifts to a region called periaqueductal grey that is associated with quick-response survival mechanisms, including fight, flight and freezing. This region is also associated with the body's natural pain killer, opioid analgesia, preparing the body to react to pain. The researchers believe that malfunctions in this system might help explain why some people suffer from anxiety disorders and panic attacks. [B][H]
Long-term memory The brain does not store long-term memories simply in static form, according to researchers at the Weizmann Institute. Using experiments on rats, they found that the brain must continuously maintain long-term memories to keep them alive. Jamming this process even briefly can erase long-term memories including memories that are many months old. These findings raise the possibility of developing future, drug-based approaches for boosting and stabilizing memory and also possibly for erasing painful memories from the past. [B][C][H]
Effects of shift working Workers who rotate between day and night shifts have less of the brain chemical serotonin than day shift workers do. Serotonin is both a hormone and a neurotransmitter, and low levels of serotonin are associated with sleep problems, anger, depression and anxiety. [B][H]
Active brain wiring Information travels between brain cells along hairlike extensions called axons. It was thought that in the cerebral cortex, where most cognitive processes occur, information was processed in the neural cell body and that the axons were just wires transmitting the output to other neurons. However, scientists at UC Irvine have discovered that the axons do not just transmit information passively, but also seem to amplify and attenuate the signals depending on their local environment. The surprising discovery came from experiments on mice to explore how nicotine alters neural processing. The researchers found that nicotine was not affecting processing in the cell body, but was instead affecting the axons. The results suggest that the axons may play a big role in cognitive functions and perhaps in consciousness, and also in psychiatric disorders such as depression and schizophrenia in which it is thought that different parts of the brain do not communicate correctly with each other. [B][H]
Neural cause of depression Clinical depression is one of the leading causes of disability and lost productivity in the world, according to the WHO. But what causes depression is still not well understood. Brain imaging studies have now shown that people with clinical depression react very differently than healthy people when trying to cope with negative situations. In both healthy and depressed individuals, the imaging showed that cognitive effort to control emotions increased brain activity in prefrontal cortical areas known to help regulate the emotional centres of the brain. In healthy individuals, this correlated with lowering of activity in the emotional response centres, including the amygdala, showing they were successfully quelling their emotional response. In depressed patients, however, high levels of activity in the amygdala and other emotional centres persisted, and even increased. [B][H]
Another approach to Alzheimer's Scientists from the University of Rochester have shown that removing amyloid-beta from the bloodstream may provide a new approach for treating Alzheimer's. The researchers discovered that in healthy people, a protein known as sLRP binds to and neutralises most of the amyloid-beta peptide that is circulating in the blood stream. However sLRP is deficient and defective in Alzheimer patients and as a result they have three to four times more loose, unbound amyloid-beta in their bloodstream. The researchers synthesizing a super-potent form of sLRP, called LRP-IV, and showed this virtually eliminated all amyloid beta in blood samples from Alzheimer patients. In mice with features of Alzheimer’s disease, LRP-IV lowered the levels of amyloid-beta in their brains by 85 to 90 percent. The mice that received the compound showed improved learning and memory compared to controls. [B][H]
Cause of Parkinson's Neuroscientists have long believed that the tremors, stiffness and sluggish gait characteristic of Parkinson's disease result from the death of neurons in the midbrain that produce dopamine, a neurotransmitter that helps to maintain proper motion control. However, a new study in mice suggests that the disorder may also be due to loss of neurons in the locus coeruleus region of the brain stem that produce norepinephrine. They found that mice genetically engineered so that they could produce dopamine but not norepinephrine, exhibited the full range of Parkinsonian impairment. The researchers say that norepinephrine controls the release of dopamine. So without norepinephrine the dopaminergic cells can produce the dopamine but it remains unavailable. The findings could lead to new treatments. [B][G][H] DNA vaccine against MS An experimental DNA vaccine for people who have multiple sclerosis (MS) has proved safe in initial small-scale trials. The results suggest that the vaccine can quell the self-destructive immune reaction against the myelin sheath of nerves, which is thought to cause MS. The vaccine introduces a gene that seeks to induce immune tolerance of myelin basic protein. The gene encodes a slightly altered version of this protein in which the immune-stimulating parts are replaced with immune-suppressing ones. Spinal fluid obtained from three patients before and after getting the vaccine showed a reduction in rogue antibodies against myelin. In addition, blood samples from five patients showed a decre | |||