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Top Stories in Science
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December 2006 Issue |
| [D] Defence and security |  |
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Limited nuclear war A small-scale, regional nuclear war could not only produce as many direct fatalities as all of World War II but could also disrupt the global climate for a decade or more, according to researchers at Rutgers, University of Colorado, and UCLA. Their climate simulations found that a regional war in the subtropics involving an exchange of 100 15-kiloton weapons would produce large climatic effects in regions far removed from the target areas. There would be a cooling of several degrees over large areas of North America and Eurasia, including most of the grain-growing regions and the effects would last much longer than cooling produced by major volcanic eruptions. [D][E][X]
Biological weapon ban The convention banning biological weapons came into force in 1975 and is the world's oldest disarmament treaty, ratified by 155 countries. But advances in biotechnology and the lack of a verification mechanism are making it increasingly difficult to enforce the treaty. [D][G][N][R]
H5N1 risk Examination of samples of H5N1 bird flu virus taken from avian and human victims has revealed that in some of the human samples the H5 haemagglutinin has acquired the ability to bind to human cell-receptors. This binding is thought to be a key step for the H5N1 virus to be able to spread from human to human. Further analysis revealed two separate mutations at different positions on the haemagglutinin molecule that had enabled it to recognise human receptors. The researchers say that identifying these will help in spotting H5N1 strains particularly likely to lead to a human pandemic. But the fact that a pandemic has not already occurred suggests that other yet unidentified changes to the virus may also be needed before it could become really dangerous. [D][G][H]
Pandemic defence US researchers have statistically analysed the historical record to find what practices helped in 1918 to reduce the effects of the H1N1 Spanish flu pandemic. They found that cities like St. Louis, which instituted "social distancing" at least two weeks before flu cases peaked in their communities, had flu-related death rates less than half that of Philadelphia, which did not act until later. The more that social distancing measures were used and the longer they were in place, the less severe was the pandemic's effect on a particular city. Wearing masks in public, restricting door-to-door sales, cancelling church and other meetings, and quarantining sick people were among the layers of measures that appeared beneficial. [D][H][X] |
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| [A] Aeronautics and space | |
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A350 go-ahead EADS has approved the development of its planned A350 mid-sized, long-haul passenger jet. The A350 will be capable of carrying up to 350 passengers and will be a competitor to Boeing's 787 Dreamliner. [A]
Space elevators One challenge that confronts hopes for the future use of space elevators is how to shield astronauts whilst they travel through the Van Allen radiation belts. Space elevators had been planned to be anchored on an ocean platform near the equator, with the other end tied to a counterweight in space. At the equator, the most dangerous part of the radiation belts extends from about 1000 to 20,000 kilometres in altitude. The region did not hurt the Apollo astronauts in the 1960s and 1970s because their rockets delivered them through it very quickly. [A]
Thinning thermosphere Evidence suggests that carbon dioxide released through the burning of fossil fuels is cooling the upper atmosphere and therefore causing it to contract towards Earth. Careful studies of the orbital trajectories of satellites in the thermosphere reveal that they are experiencing less atmospheric drag than before. This implies that the density of this part of the upper atmosphere has been dropping at 2-3 percent per decade, which is in line with theoretical predictions based on rising carbon dioxide levels. Low Earth-orbit satellites could remain in orbit longer; so also will space junk. [A][E]
Space weather forecasting Flickering loops of plasma above the Sun's churning surface have been captured in movies made by Japan's Hinode (Solar-B) spacecraft. By continuously recording the Sun's activity in visible light, UV and X-rays, the Hinode project scientists hope to gain a better understanding of the Sun's ever-changing magnetic fields and the conditions that produce solar eruptions that threaten the safety of satellites and astronauts. The hope is to be able to predict when dangerous eruptions are likely to occur. They are believed to be caused by sudden reconnections in the Sun's magnetic field. [A][R]
Turbulence in space Turbulence in space has been directly measured for the first time by a suite of four satellite detectors, called Cluster, which are positioned just outside the bow shock, the place where the solar wind gets disturbed and passes by the Earth's magnetosphere. The waves in the shock-upstream plasma, pushed around by complex magnetic fields, are observed to behave much like fluid turbulence on Earth, and the data is primarily in accord with the leading theory of fluid turbulence, the so called Kolmogorov model. [A][R]
Moon colony NASA has announced plans to permanently occupy an outpost at one of the Moon's poles. The first four astronauts will land for a short visit in 2020, but it will take until at least 2024 to prepare for a fully functional presence with rotating crews. The plan is that the US will build the transportation infrastructure and the initial capabilities for communications, navigation and operation around the base. But the US is seeking help from other countries and private corporations in other areas, including the lunar habitation modules, power, logistics and robotics. [A][I][P][R][U]
Lunar strategy and architecture NASA has unveiled the initial elements of the Global Exploration Strategy and a proposed US lunar architecture, two critical tools for achieving the vision of returning humans to the moon. The Global Exploration Strategy focuses on the reasons for returning to the Moon and what to do there. The lunar architecture focuses on how humans might accomplish the Moon exploration. [A][U]
Liquid water on Mars Observations by rovers and orbiters indicate that liquid water once covered large parts of the planet's surface, perhaps for more than a billion years. Now, NASA photographs have revealed that liquid water may still be present underground. Bright new deposits seen in two gullies on Mars that have appeared during the past seven years suggest that liquid water is emerging from beneath the ground and briefly flowing down the slopes before freezing and evaporating. If this proves correct, the presence of liquid water greatly increases the likelihood that Mars could harbour life. [A][T]
COROT ESA reports that the COROT space telescope is expected to be launched at the turn of the year. Once in orbit, COROT will become the first spacecraft devoted to the search for rocky planets, similar to our own Earth. COROT will use its telescope to monitor closely the changes in a star’s brightness that comes from a planet crossing in front of it. While it is looking at a star, COROT will also be able to detect ‘starquakes’, acoustical waves generated deep inside a star that send ripples across a star’s surface, altering its brightness. The exact nature of the ripples allows astronomers to calculate the star's precise mass, age and chemical composition. This technique is known as asteroseismology and ESA’s Solar and Heliospheric Observatory (SOHO) has been taking similar observations of the Sun for years. The COROT data will therefore enable other stars to be compared with the Sun. [A][R]
Primordial meteorite globules Hollow spheres found in a primordial meteorite could yield clues to the origin of life on Earth. NASA scientists say that "bubbles" like those in the Tagish Lake meteorite could have provided a protective envelope for organic molecules important for the emergence of life. The isotopic ratios in these globules show that they formed at temperatures of about -260C and they could be older than the Solar System. [A][G] |
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| [U] Unmanned vehicles and robotics | |
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UAV remote control By flying a jet airliner over England with no pilot in the cockpit, the UK MoD and QinetiQ are testing technology to enable a fighter pilot to control a swarm of UAVs. In the trial, the pilot sat at the back of the airliner and remotely controlled the plane plus four computer-simulated UAVs on a virtual attack mission. In the next trial, a pilot in a Tornado will simultaneously fly the Tornado, the unpiloted jet airliner and several simulated UAVs. [U][A]
Self-adjusting robot Researchers at Cornell and the University of Vermont have developed a robot that can work out experimentally how it is assembled and how to walk, and can find a new gait when it is damaged. The machine has many different candidate models of itself and these models compete over which can best explain the experiences of the robot, past and present. The test robot is a simple four-legged device, but the researchers say the underlying algorithm could be used to build more complex robots that can deal with uncertain situations, like space exploration. They think the algorithm could have other applications in computing and might lead to better understanding of animal cognition. [U][A] |
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| [P] Propulsion and energy | |
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Carbon trading The European Commission is setting tough new limits on industrial carbon dioxide emissions. Overall, for the ten nations for which figures have so far been announced, the limits are nearly 7 percent below the levels requested by the national governments, and also 7 percent below the actual recorded emissions in 2005. Each national government will divide its allocation between the nation's industries. Any industrial plant that wants to emit more than its allocation can buy emissions rights from any other European plant in the carbon trading scheme. [P][E]
Carbon footprint A scheme designed to help companies measure the total amount of carbon emissions from their goods and services has been launched by the Carbon Trust. The "cradle-to-grave" initiative will provide businesses with a profile of products' pollution, from the sourcing of raw materials through to disposal. A recent poll by the Trust showed that two thirds of people want to know the "carbon footprint" of their purchases. [P][E]
Renewable energy Renewable sources currently provide about 6 percent of the energy used in the US. According to an interim RAND report, this could be boosted to a total of 18 percent by 2025, equivalent to 25 percent of electricity and motoring fuel, at no extra cost. The provisos are that the price of renewable energy continues its downward trend and that predictions of future oil prices are roughly accurate. [P][T]
Microbial energy A review of microbial energy conversion technology has been published by the American Academy of Microbiology. The report describes in detail the various methods by which microorganisms can and are being used to produce fuels including ethanol, hydrogen, methane and butanol. It also discusses the advantages, disadvantages and technical difficulties of each production methodology as well as outlining future research needs. The report also covers the use of microbial fuel cells to convert food sources directly to electrical energy. [P][E][T]
Solar generation of hydrogen Plants and photosynthetic microorganisms are able to split water into hydrogen and oxygen using the energy of sunlight. If this process could be copied artificially, it could provide a vast source of hydrogen. German and US researchers have taken a major step towards this goal by determining the precise structure of the part of the photosynthetic cluster in which water is split. There are four manganese atoms, one calcium atom and at least five oxygen atoms linked together, and their arrangement is crucial to making the photosynthesis process work. By comparing experimental results computationally with all of the possible atom arrangements, they found that only one arrangement fitted all the data. [P][M][N]
Solar generation of hydrogen Scientists from Waseda University in Japan and Imperial College London have developed an alternative to photosynthesis for using solar energy to split water into hydrogen and oxygen. They synthesised a large molecular complex from albumin, a protein found at high levels in blood serum, and porphyrin, a molecule that carries oxygen around the body and gives blood its deep red colour. They modified the porphyrin molecule so that it had a zinc atom in the middle rather than an iron atom. They also modified the albumin molecule by genetic engineering to enhance the efficiency of the water-splitting process. [P][G][N]
Ship sky-sail A German shipping company plans to unfurl a giant high-tech kite over a cargo ship next year to boost the vessel's propulsion and to conserve fuel. The "SkySail," a 160 square-metre kite tethered to a mast, has successfully undergone years of trial runs and the company believes it will help its vessels cut fuel use by 15 to 20 percent. [P][E][M] |
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| [M] Materials, structures and surfaces | |
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Hydrogen storage material Ethylene molecules with titanium atoms attached at each end might be the basis for a hydrogen storage material, according to US researchers. They calculate that the material could absorb about 14 percent of its own weight of molecular hydrogen and that the hydrogen can be released again by modest heating. This is twice the US DoE's minimum target of 6.5 percent for economically practical storage of hydrogen in a solid state material. [M][C][P]
Triple shape materials MIT and Helmholtz researchers have invented a new class of plastics that can assume three different shapes, each shape depending on how much heat is applied. [M][H][P][S][W]
Structure of collagen An MIT researcher's mathematical model explains for the first time the distinctive structure of collagen, a material key to healthy human bone, muscles and other tissues. The new model shows collagen's structure from the atomic to the tissue scale. An improved understanding of nature's most abundant protein could aid the search for cures to such ailments as osteoporosis and scurvy, all recognized as arising from diseased collagen. [M][C][H][N]
Strength of bone Scientists at Max Planck have found a new design principle at the nanoscale that they say is responsible for the enormous stability and deformability of bone. They found that bone tissue may deform differently at different scales because of the shearing of a thin glue layer between the fibres that make up bone, as well as between the tiny mineral particles that lie inside a fibre. This construction allows bones to sustain large strains without breaking, despite being made of essentially rigid units at the molecular level. [M][H][N]
Germanium clathrate Scientists at Max Planck and the University of Houston have made a new form of germanium which has a clathrate structure. Normally a clathrate, or cage compound, is a chemical substance consisting of a lattice of one type of molecule trapping and containing a second type of molecule. However, in the case of germanium, no second molecule is needed to stabilise the cage structure. The new material is formed by a solution technique at relatively low temperature of around 300 degrees C and can easily be scaled to prepare thin films and other functional forms. At present it is not clear how this new materials might be used, but it is predicted to have unusual thermoelectric and optoelectronic properties, such as the potential to emit light. [M][J][O][S]
HTS pseudogap Researchers at Brookhaven National Lab believe they have solved the 20 year mystery of why high temperature superconductors (HTS) have an energy pseudogap. Their work suggests that above the superconducting transition temperature Tc, the electrons in a HTS bind together into pairs just as they do in a low temperature superconductor. But in the HTS case this pairing does not produce superconductivity because thermal fluctuations prevent phase coherence forming between the pairs. Only when the material if cooled to below Tc do the fluctuations become sufficiently suppressed for the phases to become locked so that the electron pairs can act coherently and the system becomes a superconductor. [M][P]
Breathable chemical protection suits At present, the only sure way to protect people from all toxic chemicals, vapours and aerosols to which they might be exposed is to use a hermetically sealed body suit and fully enclosed breathing apparatus. An alternative, used by the military, is a heavy overgarment lined with activated carbon that can adsorb vapours for a limited time. But such garments are cumbersome and costly, and they can still cause heat exhaustion, especially in hot conditions. To overcome these problems, US researchers have now developed a synthetic rubber material tailored with liquid crystals, which they say is lightweight and breathable whilst still blocking the passage of toxic chemicals. [M][N]
Biocidal coating A new "antimicrobial paint" that can kill influenza viruses has been developed by researchers at MIT. The paint coats a surface in spiky polymer molecules and these seem capable of gouging holes in the cell wall of any flu viruses or other microbes that contact the surface. The polymer molecules stay rigid because they are all positively charged and therefore repel each other, like strands of hair standing on end from a static charge. The coating may be particularly useful in public spaces such as hospitals and airplanes for preventing flu infection being transferred via surfaces that people touch. [M][H][N]
Ultrablack surfaces Blasting the polished surface of any metal with femtosecond pulses of laser light can turn the surface ultrablack, according to research at the University of Rochester. Because the pulses are so short, they produce very localised melting. This creates nanoscale patterns of cavities and protuberances that trap and absorb incident light and give almost perfect absorption. Ultrablack surfaces are of interest for use in optical and infra red sensors, solar cells and camouflage. [M][O] |
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| [E] Environment, transport and marine | |
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Climate and ocean currents Using data on global changes in methane concentrations derived from trapped air bubbles in ice cores, the European Project for Ice Coring in Antarctica (EPICA) has found a precise link between climate records from Greenland and Antarctica. The link appears to be due to a seesaw effect in the Atlantic Meridional overturning circulation. Antarctica warmed several times in the period from 20,000 to 55,000 years ago and at the same time the export of warm water from the southern ocean was reduced and the Arctic was cold. Vice versa, every time more warm water started to flow into the North Atlantic, the Arctic became warmer and the Antarctic cooler. This coupling needs to be built into climate and ocean circulation models. [E]
Southern Ocean could slow global warming The westerly winds in the Southern Hemisphere have moved southward in the last 30 years. A new climate model predicts that this will substantially increase the transfer of heat and carbon dioxide from the surface waters surrounding Antarctica into the deeper, colder waters. This transfer will reduce the rate of global warming, but on the other hand it will speed up the warming in the ocean and hence the rise in sea levels due to thermal expansion. [E]
Global warming and phytoplankton According to US scientists, global warming of the surface layer of the oceans will inhibit the flow of nutrients from the cool depths and thereby reduce the growth of phytoplankton. This will not only stifle the ocean food chain but also increase global warming, since phytoplankton capture more than 100 million metric tons of carbon dioxide out of the atmosphere each day. [E]
Phytoplankton and global warming Phytoplankton may affect global warming not only by absorbing atmospheric carbon but also by increasing cloud cover and the reflection of sunlight back into space. Atmospheric scientists have been seeking to explain increased cloud cover observed over an area of the Southern Ocean where a large bloom of phytoplankton was occurring. They have found that the concentration of cloud droplets may have been doubled by airborne particles produced by oxidation of isoprene, a chemical emitted by the phytoplankton. [E]
Kyoto protocol The UN climate talks in Nairobi in November 2006 ended in partial success but without any deal on another round of mandatory cuts in emissions to follow the Kyoto Protocol, and with no firm timetable for negotiating cuts. The European Union, with the support of a number of other nations, wanted a root and branch examination of emission targets and all the other components of the protocol. The plan now is for such a review to take place in 2008. According to environmentalists and industrialists at the conference, this delay threatens to leave the world in climatic limbo after 2012. Key economic instruments for tackling climate change, such as carbon trading, could collapse without a firm timetable. [E][P][X]
Climate-resilient agriculture The Consultative Group on International Agricultural Research (CGIAR), in consultation with the global environmental change science community, is refining a comprehensive agenda for new crops and farming methods to combat climate change. New crops are being bred to withstand heat, salt, drought and being submergence or waterlogging. More efficient farming techniques can help poor farmers make better use of scarce water and fragile soil. New crops and farming techniques can reduce greenhouse gas emissions. [E][T]
Hurricanes in 2006 The Atlantic hurricane season in 2006 has been much milder than predicted. The reason for this is not fully understood, but the late development of a hurricane-suppressing El Nino phenomenon and an unusual amount of sub-Saharan dust in the atmosphere over the Atlantic are both thought to be major factors. [E]
Deep trawling Marine scientists say the case for a moratorium on the use of heavy trawling gear in deep waters is now overwhelming and should be put in place immediately. A new report prepared for the UN indicates the equipment is doing immense damage to the ecosystems around seamounts. [E] |
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| [R] Remote sensing and sensor systems | |
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Monitoring aquifers Observations over the past 5 years by NASA's Gravity Recovery and Climate Experiment (GRACE) provide a new picture of how Earth's freshwater resources are distributed globally and how they are changing. Researchers are using the data to estimate seasonal water storage variations in more than 50 river basins that cover most of the world's land area. Several African basins, such as the Congo, Zambezi and Nile, show significant drying over the past five years, whilst in the US, the Mississippi and Colorado River basins show water storage increasing. GRACE's ability to measure water underground is very important for finding out if key aquifers are being depleted due to over-exploitation. [R][A][E]
GLONASS and Beidou satellite navigation Russia has announced that all security restrictions on the GLONASS satellite navigation system will be lifted on 1 January 2007 to foster economic development. GLONASS was developed in the 1980s as the Soviet Union's rival to GPS. It transmits two signals - an "open" one, accurate to about 50 metres, and a more accurate signal that has hitherto been limited to the Soviet or the Russian military. China has likewise announced that its Beidou navigation system will offer an open service from 2008 with an accuracy of 10 metres. Beidou current has 3 geostationary satellites and is planned to have 35 satellites eventually of which 5 will be geostationary. Beidou is likely to provide navigation services inside China and possibly worldwide. China is also a member of the Galileo project. [R][A][E]
MIRAVI ESA has launched a new website which gives users the chance to view images of the Earth from the world's largest Earth observation satellite in near real time. The MIRAVI website tracks the Envisat satellite around the globe, generating images of natural events in progress, such as fires, floods and volcanic eruptions. The images are placed online within two hours. [R][V]
Audio telescope According to the US FAA, bird strikes have caused $2 billion of damage to US-owned aircraft since 1990. Strikes are most likely to occur on low-altitude flight paths near airports and they are most dangerous to smaller aircraft. Radar and infrared sensors can see birds but cannot tell whether they are large enough to be a serious threat. To overcome this problem, NIST has developed an "audio telescope" that can be trained on a distant flock of birds after it has been spotted using radar or infrared. The telescope uses an array of 192 microphones arranged on the ground in concentric rings nearly 2 metres across. Software originally used for human voice identification has been modified so that it can identify the birds from their calls. [R][A]
Bat bi-sonar Researchers in China have shown how bats' bizarrely wrinkled, folded, and grooved faces can improve their sonar. Using computer modelling they have found that when a bat emits sound from its nostrils, grooves on its face resonate and direct different frequencies in different directions. Lower frequencies at 60 kHz resonate and are spread across a wide field of view, whilst higher frequencies are focused in an oval spot straight ahead. This suggests that bats may use an array of "acoustic flashlights", each shining a spotlight of different size, shape, and position on its surroundings. [R]
Elasticity imaging A new ultrasound technique allows radiologists to accurately distinguish benign from malignant breast lesions by measuring the tissue elasticity. It works by determining how far an ultrasound beam moves the tissue. In trials on 80 patients with 123 lesions, the elasticity imaging technique correctly identified all 17 malignant lesions and 105 of 106 benign lesions. [R][H][M][S]
Surveillance through walls A hand-held device that can peer through walls has been developed by Cambridge Consultants. It could let police or soldiers check whether anyone is lurking inside a building before bursting in, and could also help emergency workers quickly locate people trapped inside a structure. When held against a wall, the device captures a radar "snapshot" of the area in front of it and uses this as a background reference in order to detect movement. Its built-in screen produces a 3D picture of activity on the other side of the wall, pinpointing people up to 20 metres away. [R][D][S]
Flash x-ray imaging An international team of scientists has validated the idea of using extremely short and intense x-ray pulses to capture images of objects such as proteins before the x-rays destroy the sample. Using the DESY free electron laser in Hamburg to generate flash x-ray pulses, they were able to record a single diffraction pattern of a nanostructured object in only 25 femtoseconds with a resolution of 50 nm. The researchers say that using new x-ray lasers currently under construction it should be possible to produce images of complex biomolecules with atomic resolution. The flash x-ray imaging technique should also be valuable for plasma physics and materials science. [R][G][M][N]
Ultrasound stethoscope Conventional stethoscopes cannot be used in very noisy environments, such as inside a rescue helicopter, because the acoustic signal they detect is drowned out by the background noise. US researchers have developed a noise-immune stethoscope that uses an ultrasound beam. The reflected ultrasound is Doppler shifted by the movements of the heart and lungs, and this is then converted to audio frequencies. [R][H][S]
Lateral line array Although fish can see and hear, they also rely critically on a linear array of around 100 flow sensors running from gills to tail on each side of their body. The sensors are triggered by subtle water movements, and from the time differences along the array the fish's brain can reconstruct an image of what has caused the movements. Researchers at the University of Illinois have mimicked this ability by using an artificial line sensor array consisting of 16 tiny flow sensors. They have shown that with suitable signal processing the sensor array can detect vortices left in the wake of an object moving through the water. The researchers believe that the technology could have many applications, including in submarines and autonomous underwater vehicles. [R][S][U] |
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| [S] Sensor devices | |
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Magnetic sensing Potassium magnetometers may provide a very sensitive way to detect certain explosives and to measure the faint magnetic fields generated by the heart and brain, according to research at George Mason University and Princeton. [S][B][D][H]
Bee explosive sensor The honey bee's sense of smell rivals that of dogs. But attempts to exploit honey bees as sensors have been thwarted by the problem of how to get a read out of the bee's response. Now scientists at Los Alamos have found a way to do this by training honey bees to extend their proboscis in response to vapours from TNT, C4 and TATP explosives and from propellants. [S][D]
Drug sensor Researchers at the University of Illinois have developed a simple "dipstick" test for detecting cocaine and other drugs in saliva, urine or blood serum. The test is based upon DNA-gold nanoparticle technology, and can be packaged in user-friendly kits similar to those used for home pregnancy tests. [S][D][H][N]
Gene nanosensor Swiss pharmaceutical group Roche Holding AG has unveiled a new method that can track patients' responses to treatments by monitoring their genes. It uses sensors attached to tiny ultra-sensitive silicon cantilevers only 450nm thick, and it can detect active genes directly and almost instantly. [S][G][H][J][N]
Influenza gene chip Scientists from the University of Colorado at Boulder and the Centers for Disease Control and Prevention have developed an inexpensive "gene chip" test that could allow scientists to quickly identify flu viruses, including avian influenza H5N1. The test is based on a single influenza gene and may be able to keep up with changes in influenza viruses without needing frequent updating. [S][D][G][H]
Pneumonia lab-on-a-chip A new lab-on-a-chip can identify single bacterial cells for the most common cases of drug-resistant pneumonia. This should make it possible to identify and start treating the specific pneumonia strain in just hours rather than taking days, as happens at present. [S][G][H]
SERS virus detector A team at the University of Georgia has found a way to make surface enhanced Raman spectroscopy (SERS) sufficiently sensitive to detect viruses. The researchers say that the technique is so powerful that it has the potential to detect a single virus particle and can also discern virus subtypes and those with mutations such as gene insertions and deletions. This specificity makes it valuable as a diagnostic tool, but also as a means for epidemiologists to track where viruses have originated from and how they change as they move through populations. The key to this breakthrough was finding how to greatly amplify the SERS signal by using aligned silver nanotubes to hold the sample. [S][D][H][O] |
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| [O] Optoelectronics, optics and lasers | |
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Distortion-free wide-angle lens Fish-eye lenses are currently used when a very wide angle of view is needed. But they produce significant visual distortion. South Korean researchers have now designed and built an inexpensive optical lens that collects light from a large area and produces a virtually distortion-free wide-angle image. The new lens may be particularly useful for security cameras and robot navigation. [O][D][R][U]
Photonic circuits and sensors By infilling pores of a photonic crystal with a high refractive index liquid, Italian and German physicists have turned each pore into a photonic device. In this way they have created a multi-component photonic circuit inside a photonic crystal. The liquid, a solution of water and Rhodamine 6G (for fluorescence observation), introduces a permitted state locally within the photonic band gap, creating an optical defect in the crystal. The researchers say that the technique can be used to make simple components: a point defect can act as a microcavity and a line of defects as a waveguide. The technique can also be used to make more sophisticated devices like channel drop filters, optical switches and low threshold lasers. The researchers also think the technique might be used for sensor chips by using a liquid that changes its optical properties with exposure to gas or biological species. [O][M][N][S]
Strontium optical clock Optical atomic clocks could be much more precise than the conventional microwave atomic clocks that have been used for the past 50 years. Higher precision would improve synchronization in navigation and positioning systems, in telecommunications networks and in wireless and deep-space communications. It could also allow more precise measurements of the fundamental constants to see whether these are varying over time. So far, however, optical clocks have been plagued with instabilities caused by motion of the atoms. One way to tackle this problem is to use a single atom that is easy to shield; NIST researchers recently developed such a clock using one mercury atom. However, the signal from a single atom is extremely hard to measure. Japanese scientists in 2005 produced a clock that instead used many strontium atoms held in an optical lattice, but this was still not stable enough. Now NIST-JILA scientists have achieved a great improvement by using ultra-stable lasers to keep the optical lattice more rigid and so prevent the strontium atoms from moving. [O][F][I][R][S]
Metamaterial teraHertz modulator Researchers at Los Alamos have used an artificially-structured "metamaterial" to build a teraHertz modulator. They say that the device can modulate a beam at around 1 THz with 50 percent efficiency. The device uses an array of micron-sized structures that each combine two inductive rings with a parallel-rod capacitor. When a voltage is applied across the array it absorbs THz radiation in a narrow frequency band. When the voltage is switched off the structure becomes more or less transparent to THz radiation. This narrow-band operation means that the array could be used to create filters that selectively block or transmit specific THz frequencies. [O][I][M][N][R] |
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| [I] IT, communications, networking and secure systems | |
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Mobile phone safety A Danish study has provided the strongest epidemiological evidence so far that long or short-term mobile phone use is not associated with any increased risk of cancer. The study, over the past 21 years, has followed more than 420,000 mobile phone users in Denmark and has used data from mobile phone company records rather than relying on users' subjective recollections of their phone usage. More than 56,000 people in the study had been using a mobile phone for at least 10 years. [I][H][R]
Digital world Half the world population is likely to use a mobile phone by the end of 2008, according to the International Telecommunications Union's "Internet Report 2006: Digital Life". The report warns that as the digital revolution increases its grip on humanity, it is transforming not only business but also human lifestyle including the way people interact and their privacy, security and identity. If this were to slide out of control, it could lead to a backlash of user distrust and reticence that could undermine the digital world. [I][K][V][X]
Environmental data network An intergovernmental organisation called the Group on Earth Observations (GEO) has launched a system called GEONETCast that enables multiple forms of environmental data from all over the world to be collected, exchanged, combined and provided to users. There are three GEONETCast centres, located in America, Europe and China. The associated satellite network is run by a consortium of the European Organisation for the Exploitation of Satellites, the World Meteorological Organisation and the governments of America and China. [I][E][K][R]
New form of spam Computer security experts are struggling to cope with a new type of spam sweeping the internet. The emails can bypass conventional spam filters because they contain images of messages rather than actual words and sentences. [I]
Crypto-security To speed up their operation, modern microchips use "branch prediction". This involves second-guessing whether the logical flow of a computer program will follow one branch or another, prior to its actual execution. According to an international team of researchers, this creates a serious security weakness. The researchers claim to have used the attack method, dubbed "Simple Branch Prediction Analysis", to discover a 512-bit encryption key in just a few milliseconds. The key is of a type widely used to secure both online financial transactions and email messages against eavesdropping. [I]
Detecting stego images Steganography is a way to hide messages in seemingly innocent digital images. Two mathematicians at Iowa State say they have developed a pattern-recognition system using an artificial neural net (ANN) that can distinguish between innocent images and stego images that hide other information. The ANN program was trained on a database of more than 10,000 images. The database was built using 1,300 clean images, a certain percentage of which were altered using various stego embedding techniques. In preliminary tests, the ANN identified 92 percent of the stego images and flagged only 10 percent of the innocent images. [I] |
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| [K] Knowledge, information and technology management | |
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Ambiguity resolution Searching the web for someone with a common name could become easier with software that automatically distinguishes between individuals by analysing the details of search results. The program, developed at the University of Tokyo, analyses the first 100 results returned by Google in response to a name search. It then examines common words and other content in each summary to see if any results may relate to different people with the same name. The tool might also be useful in language processing because it can provide a better understanding of a statement by distinguishing between ambiguous alternatives. [K][I][V]
DNA code breaking A computer program developed at the University of Bradford could provide a way to analyse the sequences of nucleotides in a genome and to decode them into their significant groupings. As a test, the program was applied to a version of the entire text of Emma by Jane Austen after removing all the spaces and punctuation, leaving just a long impenetrable line of letters. Despite having no knowledge of the English vocabulary or syntax, the programme managed to identify 80 percent of the words and separate them back into sentences. [K][G]
Decision support Software that generates a plan of action for tackling forest blazes is being tested by fire-fighters in Spain. The system rapidly decides how best to allocate the resources needed to put out a spreading fire. [K][D][E]
Effective advertising According to research at the University of Bath, successful advertising depends far more on creativity and emotional content than on any factual message. The study looked at the perceived impact of 23 TV ads in the US and 20 in the UK. It found that advertisements with high levels of emotional content enhanced how viewers felt about brands, even when there was no real message. In contrast, advertisements which were low on emotional content had no effect even if the ad was high in news and information. [K][B][V]
Windows Vista Microsoft has started the roll-out of its new operating system, Windows Vista. Initially Vista is being made available to business customers only. [K]
High-leverage innovation A study of innovation, carried out by Booz Allen Hamilton and covering the world's 1000 largest corporate R&D spenders, has concluded that higher spending on R&D and innovation does not automatically lead to higher performance. It found that no statistical relationship exists between the number or quality of a company's patents and its overall financial performance. The study concludes that less than 10 percent of companies are 'high leverage innovators'. In many companies, R&D efforts are unfocused, money is wasted in duplication, good ideas get stuck in developmental bottlenecks, and promising innovations never get to market because of flawed understanding of customers' needs, and poor marketing and investment planning. The report says that there is no single formula for success, but that companies that are high achievers seem to have in common that they focus on building multifunctional, transparent, company-wide capabilities along the innovation value chain, and they have a long term view in designing their innovation investments. [K][T]
European innovation strategy The EU Competitiveness Council has set out strategic priorities for strengthening innovation in Europe. It has identified nine priorities: an effective IPR framework at European level; creating a pro-active standard-setting policy; making public procurement work for innovation; boosting innovation and growth in lead markets; enhancing closer cooperation between higher education, research and business; helping innovation in regions; developing a policy approach to innovation in services and to non-technological innovation; improving access to early stage venture capital investment; and Joint Technology Initiatives (JTIs). JTIs are expected to be launched for a number of sectors including aeronautics, hydrogen and fuel cells, environmental monitoring, nano-electronics and security. [K][T]
Living laboratories The EU has launched a new initiative to stimulate innovation in information and communication technologies and in mobile services by moving research out of the laboratories and into the real life contexts of cities and regions. Called the European Network of Living Labs, it involves companies, public authorities and people linking up to share information, research and testing of new products. Citizens and users will be encouraged to cooperate with researchers, developers and designers to contribute to the whole innovation process. So far, about 20 European cities including London, Barcelona, Turin, Copenhagen, Helsinki, Oslo and Stockholm have joined the initiative. [K][I]
Internationalised R&D R&D is becoming increasingly internationalised. Within Europe, according to Eurostat, gross R&D expenditure financed from abroad in 2003 amounted to €5.8 billion in the UK, €2.9 billion in France and €1.2 billion in Germany. Also indicative of a growing internationalised R&D base is the ability of countries to host large numbers of students, who are the potential researchers of the future. Here again, the UK is by far the leading country within Europe. [K]
R&D in China The OECD believes that China has overtaken Japan in 2006 as the world's second leading investor in R&D. It estimates that China will have spent over $136bn on R&D in 2006, which is about 1.2 percent of its GDP. Japan's R&D investment in 2006 is estimated at $130bn, the US at $330bn, and the EU-15 at $230bn (€173bn). China also ranks second worldwide in terms of the number of its researchers, estimated at 926,000. The US currently has something over 1.3 million researchers. [K] |
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| [C] Computing, supercomputing, modelling and simulation | |
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Antikythera Mechanism A 2100-year-old clockwork machine whose remains were retrieved from a Roman shipwreck more than a century ago has been revealed to be a celestial computer. Researchers used x-ray CAT scans and high-resolution surface imaging to peer beneath the surface of the encrusted gearwheels. They found that the machine was able to simulate the movement of the Sun and Moon over decades and to predict eclipses. The computer was extraordinarily advanced in its mathematics and technology. It linked the solar year with a 19-year cycle in the phases of the Moon, and it even factored in the so-called main lunar anomaly whereby the Moon appears to move across the heavens at different speeds at different times because of its elliptical orbit around the Earth. [C][W]
Silicon-based nuclear spin quantum computer US and German researchers have shown experimentally that the nuclear spin orientation of phosphorus atoms embedded in silicon can be measured by very subtle electric currents passing through the phosphorus atoms. They say that this has resolved the biggest issue for building a phosphorus-and-silicon quantum computer, namely how to read out the data stored on the nuclear spins. [C][J][N][S]
Programmable system chips Electronic applications continue to demand increased performance, flexibility and configurability, and at the same time they also demand less power consumption, smaller size and lower cost. All of this creates more pressure to integrate as much as possible into programmable single-system chips, including analogue functions, memory, logic and soft microcontroller unit (MCU) implementations. This trend is reviewed in a recent issue of IEEE Computer. [C][I][K][T]
Quantum system simulator Researchers at Imperial College have shown theoretically that it is feasible to build a device that can simulate the behaviour of atoms and other particles according to the laws of quantum physics. The simulator would consist of atoms and photons in an array of very small silicon cavities, just 50 microns across. The atoms and photons inside the cavities would form a strongly-interacting many-body system, with photons jumping from cavity to cavity, and at the same time being scattered off each other. The researchers say that it would be possible to control how the individual particles move and interact, and hence to simulate how future quantum computers might perform. [C][J][M][N][X] |
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| [W] Whole life engineering, manufacture and testing | |
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IT-enabled business change In a report entitled Delivering Successful IT-Enabled Business Change, the UK National Audit Office has outlined good practice for avoiding the problems that have plagued some recent government computer projects. [W][T]
Website design A study commissioned by the UN has found that 97 percent of websites do not provide even minimum levels of accessibility for disabled users. [W][K][V]
Modelling natural gas production Natural gas companies would like to operate their production networks more efficiently and flexibly. But operators can be overwhelmed by the sheer number of choices to be made and obligations to be met under supply contracts with customers and facility-and-production-sharing agreements with other companies. With this in mind, MIT engineers have developed a mathematical model that could help energy companies produce natural gas more efficiently and ensure a more reliable supply. The model describes gas flow, pressure and composition inside every pipeline in the network. Equations describe how the flow properties change as the gas passes through each facility along the way. The equations interact so the model can track flows and how they mix throughout the system. [W][C][P][X] |
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| [X] Systems, complexity and risk | |
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Rainforest ecosystem Fragmentation of rainforests is a major threat to ecosystem diversity, and studies are showing that damage happens far faster than had been imagined. A big problem is that fragmentation allows hot winds from surrounding pastures to blow into the forest. The winds kill many of the massive but tender trees that are most important as a food source and habitat for the forest creatures. [X][E]
Extinction-induced ecosystem switching A new analysis of the fossil record has revealed that the Permian mass extinction that occurred about 250 million years ago not only wiped out an estimated 95 percent of marine species and 70 percent of land species, but also caused a fundamental switch to a radically new ecosystem architecture. Ecologically simple communities of low-metabolism, stationary organisms that filter nutrients from the water, such as lamp shells and sea lilies, were largely replaced by ecologically complex communities of higher metabolism, mobile organisms such as snails, clams and crabs that instead go out and find their food. [X][E]
Coupled ecosystems It is well known that any predator-prey system shows oscillations. For example, if there are lots of lions preying on zebras, numbers of zebras decline; then because zebras are scarce, lions starve and their numbers dwindle, allowing the zebra population to build up again. According to researchers at the University of Michigan, different predator-prey systems can interact like coupled oscillators and can exhibit co-ordinated chaos. Mathematically simulating such scenarios can help address fundamental puzzles, such as how species that appear to be exploiting the same resources can coexist, and why some predator-prey systems are particularly resistant to invaders. [X][C][E] |
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| [V] Virtuality and human-machine interface | |
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Beyond HDTV Rapid advances in technology could soon mean that high definition television is obsolescent, according to a review article in Computer. [V][I][K][T]
Virtual communities A survey has found that many members of online communities feel that their virtual communities are as important as their real-world counterparts. [V][I][K][X]
Virtual limb Amputees who experience "phantom limb pain" could find relief with a 3D virtual reality system developed at the University of Manchester. The system gives amputees the illusion that they can once again control their missing limb. The user wears a head-mounted display and operates a controller with their remaining limb. The system lets the user control a virtual arm or a leg, which is shown in 3D in place of the missing limb. [V][H]
Touch-sensitive interface A series of acoustic sensors that turn any surface into a touch-sensitive computer interface have been developed by European researchers. Two or more sensors are attached around the edges of the surface. These pinpoint the position of a finger, or another touching object, by tracking minute vibrations. The technology can be applied to many different shapes of objects. [V]
Wearable telehealthcare sensors Scientists from the University of Arkansas have developed an organic semiconductor micro-sensor that can be incorporated into smart fabrics to make a wearable telehealthcare monitoring device. This can measure vital signs including respiration, heart rate, ECG, and body temperature. The researchers say that organic semiconductors provide the best combination of flexibility, light weight, large area, robustness and low cost. [V][H][I][K][S] |
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| [B] Brain research and human science | |
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Long term memory During sleep, freshly minted memories move from the hippocampus, part of the "old" brain, to the neocortex, or "new" brain, for long-term storage. This has been the reigning theory for decades. Researchers at Max Planck and Brown University have now provided the strongest evidence yet of this interaction between the old and new brains. But the research also shows, surprisingly, that instead of the hippocampus uploading information to the neocortex in a burst of brain cell communication, there is a synchronised dialogue between them and the neocortex seems to drive this dialogue. [B]
Gender differences in brain processing A study of language use in children suggests gender influences how the brain processes words. Their findings suggest that girls mainly use a brain system that is for memorizing words and associations between them, whereas boys rely primarily on a system that governs the rules of language. Since the brain systems tested in this study are responsible for more than just language use, the study supports the notion that men and women may tend to process various skills differently from one another. [B][K]
Memory protein If memories are encoded in the pattern of synaptic connections between nerve cells, it is puzzling how memories can be so persistent when the synapses are in a constant state of flux, with molecules flowing in and out all the time. The answer, according to a mathematical model developed at the University of Utah, may be that connections are strengthened by an increase in the number of scaffolding proteins that anchor neurotransmitter receptor proteins in place so that they receive signals. The mathematical model accurately reflects experimental data on how, over time, synapses become stronger as more nerve signals pass through them and weaker as fewer signals are transmitted. [B]
Whales and humans Spindle cells are found in parts of the human brain that are thought to be responsible for human social organisation, empathy, speech, intuition about the feelings of others, and rapid “gut” reactions. They are credited with allowing humans to feel love and to suffer emotionally. Until now, these cells were thought to occur only in the brains of humans and primates. However, new research shows whales also possess spindle cells, and indeed spindle cells appear to be more prevalent in the brains of whales than in humans, even allowing for the larger size of whales' brains. The finding raises further questions about the ethics of hunting whales. [B][E]
Chemo brain Despite being protected by the blood-brain barriers, brain cells can be damaged by chemotherapy. Researchers at the University of Rochester have found that several types of key brain cell are highly vulnerable to chemotherapy drugs. Japanese researchers using MRI have found that within 12 months of receiving adjuvant chemotherapy, significant regions of the brain associated with memory, analysis and other cognitive functions were significantly smaller in breast cancer patients who received chemotherapy than those who did not. However, four years after treatment there were no differences in these same regions of the brain, suggesting that the damage to mental function may not be permanent. [B][H]
Producing neural stem cells The adult brain possesses neural stem cells that could potentially be used to regenerate neurons; indeed, the brains of patients with neurodegenerative disease show evidence that their neural stem cells do attempt to replace dying cells, but not on a sufficient scale. Researchers at Caltech have now shown, using mice, that they can stimulate the subventricular zone of the brain to produce a much larger pool of adult neural stem cells. [B][G][H]
Predicting schizophrenia Measuring changes in grey matter in the brain using magnetic resource imaging (MRI) could be used, in combination with other clinical assessments, to predict schizophrenia, according to scientists at Edinburgh University. Although there are no preventative treatments for the illness, an accurate predictive test for people at high risk of developing schizophrenia before they actually started showing the symptoms, could help researchers to assess possibilities for prevention in the future. [B][H][R] |
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| [H] Healthcare and medicine | |
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Human milk therapy Human breast milk contains remarkable medicinal compounds that researchers are working to reproduce synthetically using bio-engineering. The third-largest constituent of human milk, making up about 1 percent by volume, is a mixture of indigestible sugars known as oligosaccharides. They neutralise harmful bacteria in the human gut and help beneficial bacteria, giving powerful protection against diarrhoea. Another component, lactoferrin, can appropriately suppress inflammation or boost immune activity, fight viruses, bacteria and fungi. It may be useful against arthritis, multiple sclerosis, and septic shock. A third component, lysozyme, selectively destroys deleterious bacteria. A fourth, human alpha-lactalbumin, when acidified, is lethal against a very wide range of cancers and pre-cancers. [H][G][T]
Saliva painkiller Saliva from humans has yielded a natural painkiller up to six times more powerful than morphine, according to researchers at the Pasteur Institute in Paris. The hope is that the substance, dubbed opiorphin, may spawn a new generation of natural painkillers that relieve pain as effectively as morphine but without the addictive and psychological side effects of the traditional drug. [H]
Low back pain Low back pain (LBP) affects a large proportion of the adult population at some point in their lives, and in many of these cases it is persistent and eventually leads to debilitating pain. Such cases are very often due to degeneration of the flexible intervertebral disc that separates the vertebrae in the spine and protects them from damage. Research at the University of Manchester has developed an exciting new treatment for LBP that uses tissue engineering to regenerate the affected intervertebral discs. It uses a combination of the patients’ own mesenchymal stem cells (MSCs) and a naturally occurring collagen gel that can be implanted through a minimally-invasive surgical technique. The researchers believe that the treatment could hugely improve the cost and success of treating LBP. [H]
Heart stem cells Cell therapies for failing hearts have been hampered by the lack of a suitable stem cell. Now, three US research groups have separately announced that they can produce stem cells that give rise to the three different tissues found in the mammalian heart - cardiac muscle, smooth muscle and endothelial lining. Each team has identified cardiovascular “precursor” cells from cultures of mouse embryonic stem cells. The researchers say that it is very likely that these versatile cells will also be found in the embryonic human heart, raising hopes that in the future damaged hearts can be repaired and “rejuvenated” using embryonic stem cell lines grown in the laboratory. [H] |
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| [G] Genomics, biotechnology and bioinformatics | |
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Human and chimpanzee genomes By evaluating the correlated activity of thousands of genes, researchers at UCLA have identified not just individual genes but entire networks of interconnected genes whose expression patterns within the brains of humans are different from those in chimpanzees. The gene networks differed the most widely in the cerebral cortex, which is three times larger in humans than chimps. The UCLA team also found that many of the genes that play a central role in cerebral cortex networks in humans, but not in the chimpanzee, also show significant changes at the DNA level. [G][B]
Neanderthal genome Two teams of scientists, in Germany and the US, have retrieved and analyzed a large part of Neanderthal DNA. Within their margins of error, the two teams agree that the evolutionary lineages of Neanderthals and modern humans split somewhere around 500,000 years ago. This also fits with previous estimates from mitochondrial DNA and archaeological data. Future genome analysis will reveal how modern humans and Neanderthals differed and perhaps why Neanderthals died out. Their extinction has been attributed variously to lower intelligence than modern humans, worse language skills, cruder tools, lack of a propensity for long-distance trade, and most recently to modern man's more efficient and competitive division of food-acquiring labour between men, who hunt, and women, who gather. [G]
Copy Number Variants Two separate studies of the human genome have revealed an unsuspected amount of variation between people in the number of copies of genes they have. Such variations, called Copy Number Variants (CNVs), appear to involve as much as 12 percent of human DNA, and are known to be involved in some diseases. The finding makes the search for genetic causes of disease more complex, since it will be necessary to consider CNVs as well as gene mutations. [G][H]
Epigenetic inheritance A mother’s diet can change the behaviour of a specific gene for at least two subsequent generations, a new study has shown. Feeding mice an enriched diet during pregnancy silenced a gene for light fur in their pups. And even though these pups ate a standard, unenriched diet, the gene remained less active in their subsequent offsprings. The findings lend support to the idea that we inherit not only our genes from our parents, but also epigenetic changes in DNA that activate or silence specific genes. They could explain the curious results from recent studies of human populations. For example, a Swedish study found from historical data of harvests in Sweden that if a grandfather had good access to food during his childhood, his grandchildren had a four times greater risk of developing diabetes. [G]
Cotton as food For every kilogram of cotton fibre, commercial cotton plants produce about 1.65 kg of seeds. Though these seeds contain much high-quality protein, they also contain gossypol, a compound that is toxic to humans and many other animals. In the 1960s, researchers discovered mutant cotton plants that did not produce gossypol. But since the compound protects plants from insects, the plants were inundated by pests and proved a commercial failure. Now researchers at Texas A&M University have used RNA interference to eliminate gossypol only in the cottonseeds and not in the rest of the plant. They estimate that with the amount of crop currently planted, such modified cottonseeds could fill the daily protein needs of about 500 million people. [G]
Riboswitch antibiotics Most current antibiotics thwart bacteria by targeting ribosomes to stop protein synthesis or the proteins involved in DNA replication. Some other antibiotics work by interfering with the biosynthesis of cell walls or the maintenance of new cells. As bacteria increasingly develop resistance to these antibiotics, researchers believe that it will be possible to make a whole new generation of antibiotics that simply switch off bacterial gene expression by activating riboswitches in the bacteria. Riboswitches are short sections of untranslated RNA that monitor small compounds in the cell in order to control gene expression. [G][H][N][T]
Gene transcription RNA polymerase is a molecular machine that is able to move along the DNA molecule transcribing the genetic instructions into an RNA copy. This copy is then used by the cell to make proteins. This transcription process is so fundamental to life that understanding it should open up opportunities for radically new antibiotics. US researchers have discovered that RNA polymerase works by unwinding part of the DNA and pulling unwound DNA into itself. The unwinding stores elastic energy in the DNA molecule and eventually this is enough to push the RNA polymerase along the DNA molecule to copy the next set of instructions. At the same time the DNA winds up again behind it. [G][H][N]
Reverse transcriptase Normal transcription involves the synthesis of RNA from DNA. But in a newly fertilised egg, and in sperm cells and cancer cells, a reverse process also occurs in which an enzyme called reverse transcriptase synthesises DNA from RNA. Why this happens is something of a mystery, but experiments in mice at Italy's National Institute of Health show that without reverse transcriptase a newly fertilised egg cannot progress beyond four cells. This suggests that reverse transcription is crucial to initial cell differentiation. In cancer cells, blocking reverse transcription slows tumour growth but does not completely halt it. In sperm cells, reverse transcription can cause foreign RNA to be inserted into the sperm's DNA. This is worrying because it might possibly mean that in vitro fertilisation could accidentally produce transgenic humans. [G][H][N] |
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| [N] Nanotechnology and molecular technology | |
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Measuring molecular torque Many protein molecules, such as those that process DNA, execute twisting motions. But often the random thermal jiggling of water molecules makes this rotation hard to detect in the laboratory, and only in a few cases has it been possible to actually measure the molecular torque. To address this limitation, researchers at the Institute of Photonic Sciences in Barcelona have devised a method for measuring molecular torque using statistical methods that gives ten times better sensitivity. It could be applied to proteins, DNA, or even to measure the torque produced by synthetic nanomotors. [N][G][O][S]
Safety of nanotechnology A team of experts has drawn up five "grand challenges" in order to evaluate the safety of nanotechnology. [N][H][X]
Cell nanothreads Researchers at University College London have used electrospinning to create nanofibres encasing living cells. The nanothreads could be made into a tissue matrix and used for tissue engineering and regenerative medicine. [N][H]
Molecular self-alignment Dutch researchers have found that specially designed flat molecules can stack into very long columns, which align themselves into large, regularly spaced arrays covering square millimetres in area. The technique may be useful for sensors. [N][S]
Biomimetic nanoassembly Chemists at Rice University have discovered how to assemble gold and silver nanoparticle building blocks into larger structures by using micellization, a process used by all living cells to create membranes. Cell membranes and other micelles are formed from amphiphile molecules that have a hydrophilic end and an opposite hydrophobic end. The hydrophobic ends stick to one another, forming a bilayer membrane. The researchers showed that by attaching a nanoparticle to the junction point of an amphiphile, they can use micellization as a means to assemble many billions of individual nanoparticles into well-defined superstructures. The researchers believe these structures will have applications in medicine and catalysis. [N]
Complex DNA devices Nanotech systems based on DNA may be on the verge of becoming very large and complex. Researchers at Caltech have combined simple strands of DNA into the most elaborate logic circuits yet achieved, and they say there is potential for even more growth. Another group at New York University has turned DNA chains into a rudimentary robotic system, namely a grid containing dozens of flipperlike arms. [N][G]
Magnetic vortex memory Scientists at Max Planck have discovered a new mechanism with which it is possible to use weak magnetic fields to reverse tiny magnetic structures, called vortex cores, quickly and with no losses. Up until now, very strong magnetic fields have been needed to do this. The new method might open the way to use vortex cores for very high density magnetic data stores. [N] |
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| [J] Microelectronics, MEMS and spintronics | |
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Nanowire conduction Coating nanowires with an acoustically hard material improves the mobility of electrons in the wires and the usefulness of nanowires for electronic devices. Researchers have shown theoretically that coating nanowires with diamond can increase the mobility up to 100 times at very low temperatures and by a factor of two at room temperature. The effect works by reducing the scattering of electrons in the nanowire by acoustic phonons. [J][N]
Controlling nanotube properties The electrical and mechanical properties of a carbon nanotube depend strongly on its diameter. Researchers at Berkeley and Lawrence Berkeley have developed a method to shrink individual nanotubes to any desired diameter in a highly controlled fashion. The researchers also found that the conductance of a multi-walled carbon nanotube is directly proportional to its diameter. Other researchers, at Rice University, have shown that it is possible to grow carbon nanotubes from seeds. The hope is that in the future this will lead to the capability to grow large quantities of nanotubes that precisely replicate the properties of the seed. [J][N]
Single impurity effects As semiconductor devices are scaled down to nano-dimensions, one can no longer treat dopant atoms as a continuum. The device behaviour then becomes dependent on the precise position and behaviour of each dopant atom. Researchers at Delft University of Technology have for the first time managed to study the effects of a single dopant atom. They used silicon wires 35 nm wide, which were taken from commercial field-effect transistors. They were able to extrapolate the position of a single dopant atom and to measure its effect on the flow of electrons. The result is also relevant to the possibility of making a silicon-based quantum computer. [J][C][N]
Graphene spin filter Graphene might be used to generate, manipulate and detect electron spins in spintronic circuits, according to researchers at Berkeley. They found that because of the peculiar zigzag geometry left by broken hexagonal bonds, the electrons at opposite edges of a graphene ribbon can be in different states. On one edge, the occupied states are spin-up and the unoccupied states are spin-down, whereas on the other edge the reverse is true. When a voltage is applied the ribbon shows half-metallic behaviour, conducting electrons of one spin orientation but not the other. The researchers say the effect could be tailored by altering the width of the graphene ribbon. [J][N] |
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| [F] Fundamental science | |
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Dark energy Observations of 23 supernovae using the Hubble Space Telescope have shown that dark energy was already boosting the expansion of the universe as long as 9 billion years ago. The data is consistent with a constant energy density, meaning that the energy of the vacuum does not dilute itself as the universe expands and therefore that it eventually fuels an exponential growth of the universe. The finding is consistent with Einstein's cosmological constant. However, more complicated models with non-constant energy density, including a class known as quintessence models, are not completely ruled out. The uncertainty in the new data would still allow the density of dark energy to have varied by up to 45 percent. [F][R]
Black hole universality UK astronomers, using data from NASA’s Rossi X-ray Timing Explorer and XMM Newton’s X-ray Observatory, have found that the processes at work in black holes of all sizes are the same and that supermassive black holes are simply scaled up versions of small Galactic black holes. [F][R]
Black hole feeding NASA's Galaxy Evolution Explorer has enabled astronomers for the first time to watch the whole process of a black hole consuming a star. This sort of event is thought to happen about once every 10,000 years in a typical galaxy. The black hole's gravity flattens and stretches the star apart. Once a star has been disrupted, a portion of its gaseous body will then be pulled into the black hole and heated up to temperatures that emit X-rays and ultraviolet light that astronomers can observe. [F][R]
Gamma ray clock The first astronomical source of very high-energy gamma-ray pulses has been discovered by an international team of researchers. The gamma rays, which have energies greater than 100 giga electron volts (GeV), are at least 100 000 times more energetic than other known periodic signals. The gamma rays originate from a binary star system in which a compact object that could be a black hole or neutron star is orbiting around a massive "blue" star that is about 20 times larger than the Sun. The researchers believe that the gamma rays are produced by the violent interaction of the compact object with the stellar wind from the blue star at supersonic speeds. The pulsing, they believe, is caused by a fog of matter-antimatter pairs created by the gamma rays colliding with the light from the star. [F][A][R]
2006 top stories in physics The American Institute of Physics has published its list of the 27 most significant physics stories of 2006. Top of the list is the new high precision measurement of the electron’s magnetic moment, which together with a fresh formulation of quantum electrodynamics (QED) has provided a new value for the fine structure constant with an uncertainty of only 0.7 parts per billion. Comparison between this new value and values determined by other methods provides the best test yet of quantum electrodynamics (QED). [F][T] |
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| [T] Technology reviews | |
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The next 50 years As part of its 50th anniversary celebrations, New Scientist has asked over 70 of the world's most brilliant scientists for their ideas on what will be the biggest breakthrough of the next 50 years. The responses are described as separate articles under the headings of: ageing, alien life, consciousness, ecology, embryology, environment, evolution, genetics, health, humans, language, neuroscience, oceans, psychology, sex and social science, artificial intelligence, communications, computing, cosmology, space and technology, chemistry, energy, materials, maths and physics. [T][A][B][C][E][F][G][H][I][K][M][N][O][P][R][U][X]
The past 50 years Also, as part of its 50th anniversary celebrations, New Scientist has reviewed the great scientific and technological achievements, inventions and changes of the past 50 years. [T][A][C][E][F][G][H][I][J][M][O][P][R][S][V]
Seventh Framework Programme The European Parliament has approved the 7th Framework Programme with a budget of 54 billion euros. Of the different research categories, information technology receives the biggest funding, with a budget of 9.1bn euros. Research into climate change and energy, in contrast, has received a comparatively small amount of funding in the plan. [T][E][I][K][P]
Automotive R&D strategy CLEPA, the European Association of Automotive Suppliers, has published a strategic research agenda for the automotive industry. It identifies four priority areas: to improve the mobility of people and goods, by reducing congestion through technological advances and better infrastructures; to rely on sustainable energy sources, in order to limit energy consumption and pollution through the development of energy-efficient vehicles; to promote safety and security, to avoid accidents, road fatalities and security risks; to utilize materials, designs, processing, manufacturing to render the vehicle more environmentally friendly through the reduction of weight. [T][E][I][K][M][P][W]
Scientific American 2006 awards Scientific American has published its hall of fame of the 50 research, business and policy leaders of the year. Research leader of the year is Angela Belcher of MIT for pioneering the use of custom-evolved viruses in synthesizing nano-scale wires and arrays. Business leader is Swiss Re, the insurance company, for highlighting the dire consequences that may result from global warming. Policy leader of the year is Al Gore for his documentary, An Inconvenient Truth. Trends highlighted are: environmentally benign fuels and vehicles; understanding Alzheimer's disease; plasmonics, metamaterials, cloaking and optical circuits; stem cell therapy and biology; electronic tags; carbon-based electronics; bioengineering replacement body parts; advanced mobile robots; optical techniques for cheap gene sequencing; nanostructures and nanoassembly; neural interface technology for the blind, deaf and disabled; net neutrality; DNA based structures and electronics; and, the brain atlas. [T][B][E][G][H][I][J][M][N][O][P][S][U][V] |
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