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Top Stories in Science
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September 2005 Issue |
| [D] Defence and security |  |
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UN emergency fund Six countries have pledged almost US$150m (£80m) to a proposed new United Nations emergency fund. The fund would allow the UN to respond to natural disasters and other emergencies within a matter of days rather than weeks that it can take now. The British government has promised almost half of the total sum. [D][E][X]
UN summit The UN summit has achieved agreement that there is an international responsibility to protect people from genocide, war crimes and ethnic cleansing, and has also established a new Peacebuilding Commission to help countries make the transition from war to peace. On terrorism, the summit agreement condemns terrorism "in all its forms and manifestations, committed by whomever, wherever and for whatever purposes", but crucially there is still no agreement on a definition of terrorism that can distinguish terrorists from freedom fighters. The summit failed to reach agreement on a strategy to prevent the spread of nuclear weapons, or on how to reform the Security Council to make it more representative. [D][E][X]
Eradicating extreme poverty The September issue of Scientific American includes an article explaining how a large-scale and targeted public investment effort could eradicate extreme poverty globally by 2025. A new kind of development economics needs to emerge, one that is better grounded in science. Good governance makes a difference but is not the sole determinant of economic growth. Disease and water have been the key factors in the failure of economic development in Africa and other underdeveloped regions. Africa bears an overwhelming burden of tropical diseases, and tropical Africa lacks the reliable monsoons and the massive floodplains that facilitate the large-scale and low-cost irrigation found in Asia. [D][E][H][T][X]
Nuclear proliferation According to an updated global nuclear inventory published by the Institute for Science and International Security (ISIS), there were 1830 tonnes of plutonium in 35 countries at the end of 2003, enough to make 225,000 nuclear bombs. Stores of plutonium are growing, and there are new dangers from two lesser-known nuclear explosives, neptunium-237 and americium. [D][P]
Chemical weapon monitoring The Chemical Weapons Convention was signed in 1993 to ban the stockpiling, production and usage of chemical weapons. This treaty, now ratified by 170 nations, includes intrusive verification procedures that far exceed those of other treaties banning weapons of mass destruction. However, in recent years the world's chemical industry has been developing micro-reactors that range in size from a credit card to the dimensions of a notebook. For industry, this new technology permits safer processing, better chemical yields and a reduction in overall costs. However, it will also facilitate malicious clandestine operations and make chemical weapon monitoring more difficult. [D][R][W]
Military intervention The first study to examine the effectiveness of military action against genocide and politicide has found that only overt military interventions that explicitly challenge the perpetrator appear to be effective in reducing the severity of brutal policies. The study examined factors affecting all ongoing instances of state-sponsored mass murder from 1955 to 1997. [D]
Homeland Security R&D Plan The US Department of Homeland Security has released a national plan for R&D to support the protection of critical infrastructure. The plan covers nine research areas: detection and sensor systems; protection and prevention; entry and access portals; insider threats; analysis and decision support systems; response, recovery and reconstitution; new and emerging threats and vulnerabilities; advanced infrastructure architectures and system designs; human and social issues. [D][X][T]
Subway surveillance New York's subway will be scanned by thousands of cameras and motion sensors under a high-tech strategy to counter the threat of terrorist attacks. [D][R]
Electric shock weapons The Homeland Security Advanced Research Projects Agency has launched a programme on "innovative less-lethal devices for law enforcement" to radically expand the capabilities of electric shock weapons. [D]
High energy laser weapon DARPA is developing a high-powered, lightweight laser weapon that can be fitted to fighter aircraft to destroy missiles tens of kilometres away. The weapon, called the High Energy Liquid Laser Area Defense System (HELLADS), will weigh just 750 kilograms, including its cooling system, and will fit into a space of about 2 cubic metres. A prototype scaled model has so far produced a 1-kilowatt beam, and researchers hope to have a 15-kW version ready for testing by the end of the 2005. A full-sized prototype capable of firing a 150-kW beam is due to be completed by 2007. [D][A][O] |
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| [A] Aeronautics and space | |
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Airline survival Over the past four years, America’s airlines have lost $32 billion, and rising fuel costs have now forced two of America’s biggest airlines, Delta and Northwest, to file for Chapter 11 protection from their creditors. Along with United Airlines and US Airways, this means that four US carriers are now mired in bankruptcy reorganization. In Europe, low cost carriers have been able to grow rapidly by opening up new markets for cheap travel. However, demand is now saturating, and competition and pressure on costs is intensifying. There is a convergence in Europe between traditional and low cost carriers, but to hang on to their lucrative business customers, the traditional carriers must ensure that higher ticket prices correspond to significantly better service than the economy-class airlines offer. [A][P][T]
Singing wings "Singing" wings could reduce the number of fatal small plane crashes, according to Australian research. The new technology uses a sound-emitting plastic coating to help control the flow of air over the wings, reducing the chance of the aircraft stalling in mid-air. The researchers believe the technology might even lead to a new generation of smaller-winged, more fuel-efficient aircraft. [A][M][U]
Low noise aircraft The Cambridge-MIT Institute is funding a project to develop an extremely low noise aircraft, based on a flying-wing design. The initial prototype design should be finished within 12 months. [A][P]
Variable geometry wings Small robotic spy-planes have been developed that use shape-shifting wings to switch from being stable gliders to ultra-manoeuvrable fliers. Small aircraft allow new wing designs to be used. These could not scale up to larger planes because the strength required of the structures would make the wings too heavy. [A][U]
Seagull-like planes Aerospace engineers at the University of Florida have built prototypes of 6-inch- to 2-foot- drones capable of squeezing in and out of tight spots in cities. Their wings are inspired by seagulls and change shape dramatically during flight to combine agility and stability. Seagulls have remarkable ability to hover, dive and climb rapidly. This is achieved by wings flexing at both their shoulder and elbow joints as they alter flight patterns. [A][U]
Kliper spacecraft Russia, Europe, and Japan may jointly develop a crewed spacecraft called Kliper to ferry as many as six astronauts to and from the International Space Station. The spacecraft could launch as early as 2010 - just as NASA retires its space shuttles. [A]
Deep impact mission Spectroscopic analysis of the plume of material emitted from Comet 9P/Tempel 1 when it was rammed by NASA's Deep Impact spacecraft shows surprisingly high concentrations of organic molecules. This could support theories that comets may have brought water and the building blocks of life to Earth. The plume also appears to contain clays and carbonates, thought to form only in liquid water. This is surprising, since the comet is believed to have formed in the intense cold around the orbit of Neptune. It might indicate that the solar system did not simply form from dust and gas clumping together but that instead some matter was whisked outwards from warm regions near the Sun where liquid water could have existed. Measurement of the gravitational trajectory of the plume also indicates that the comet is highly porous and may have no solid core. This porosity may indicate that the comet formed very gently and gradually, built up over millions of years from the chance collision of tiny particles within the infant solar system's protoplanetary disk. [A][R]
Human mission to Mars A study by MIT for NASA has examined more than 2000 possible mission architectures for human exploration of the Moon and Mars, and selected those that require the least investment, while optimising safety and reliability. The researchers suggest that a human mission to Mars could be accomplished much sooner by adopting a more radical approach and designing the Crew Exploration Vehicle (CEV) so that components could be reused for several types of mission. They also propose that the most efficient scheme for lunar exploration would involve sending the CEV non-stop to the Moon’s surface, and then back again. They argue that this would increase mission safety by decreasing the number of critical manoeuvres required, such as orbital rendezvous and docking. [A]
European Mars mission The European Space Agency (ESA) has settled on a concept for its next mission to Mars. A single robot rover will be sent, plus a stationary package of scientific instruments. [A][U] |
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| [U] Unmanned vehicles and robotics | |
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Unmanned combat air system The X-45A has now finished its full test flight programme, having completed 64 test flights without mishap and successfully demonstrated a wide range of capabilities. [U][A]
Robotic lunar scout In order for humans to colonise the Moon or Mars, robotic scouts will need to search for safe landing spots and useful minerals for colonists to mine. Raytheon has developed a robot that might bounce across perilous craters and imposing mountains on the Moon's craggy surface using a set of compact rocket boosters. The robot, dubbed the Lunar Penguin, looks like a simple, squat, four-legged lunar lander. [U][A][P]
Autonomous repair CSIRO and NASA are developing a spacecraft skin that assesses the severity of any damage it suffers from space debris and other impacts. The skin consists of many separate cells. Behind each is an impact sensor and a processor equipped with algorithms that allow it to communicate only with its immediate neighbours. The algorithms leave digital messages in cells around the system, indicating for instance the position of the boundary around a damaged region. The cell's processor can use this information to route data around the affected area. [U][A][C][M][R]
Electronic skin A flexible electronic skin that can sense when something is too hot to handle or is being squeezed too hard could give robots an almost-human sense of touch. The skin, developed by researchers at Tokyo University, incorporates a matrix of transistors to measure pressure and a second to sense temperature. By building up more layers of sensors it may be possible to give the electronic skin sensing capabilities that human skin lacks. [U][S][V]
Robotic surgery A system that allows surgeons to perform laparoscopic gastric bypass surgery has been successfully tested in ten patients. The surgeon operates from a remote console, controlling up to three robotic arms and a binocular camera. [U][H][V] |
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| [P] Propulsion and energy | |
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Nuclear electric propulsion Spacecraft powered by nuclear fission reactors are of limited use to astronomers, according to a report from the US National Research Council. The report calls into question NASA's multi-billion-dollar Prometheus project to develop nuclear electric propulsion for future missions to the Moon, Mars, and the outer solar system. The report does identify some robotic missions where nuclear electric propulsion could be beneficial, including one to send probes and landers to Neptune. However, it cautions that there are substantial hurdles even for these missions, including the ability to operate continuously and without repairs for the decade or so that it would take to reach Neptune. [P][A]
Backpack electricity generation Scientists in the US have invented a back-pack that converts the up and down motion of walking into electricity. It could be used by troops, field scientists and aid workers to power mobile phones, GPS instruments and other devices without having to carry heavy replacement batteries. The load inside the backpack is suspended so that its motion lags behind that of the backpack frame on the walker's back, and the differential motion generates the power. The backpack alters the walker's gait, making the walking more efficient. As a result the backpack uses little more metabolic energy than walking while wearing a conventional backpack of the same weight. It is also more comfortable because the suspending springs cushion the load and reduce peak forces. The researchers tested packs with loads of 40 to 80 pounds and found that the wearer could constantly generate as much as 7.4 Watts while moving at a steady clip. [P][D][I][R][V]
Hydrogen storage materials New materials and methods are improving hydrogen storage and production technology. A huge number of materials are under investigation, notably hydrides, boron compounds, carbon nanotubes and other carbon based materials. [P][M][N][T]
Biochip battery Biochips promise to be able to test simultaneously for a variety of diseases, to give instant results, and to be very cheap. However, they need a suitable power supply. A research team in Singapore has developed a paper battery that is small, cheap to fabricate, and which ingeniously uses the fluid being tested (urine) as the electrolyte. [P][J][S]
Nuclear accidents The total amount of radioactivity released by the Chernobyl accident over 10 days in 1986 was huge, reaching 14 exabecquerels. Estimates of the likely death toll have varied greatly and have been as high as hundreds of thousands of people, spread across Europe. A new study, compiled by the Chernobyl Forum, has reached the more reassuring prediction that the real number of deaths from long-term cancers caused by the radiation will be about 3940. The deaths will be among the 586,000 people most contaminated by the accident - the 200,000 clean-up workers, the 116,000 evacuated from around the plant and the 270,000 residents of the most radioactive areas. The study suggests that mental illness has been the biggest public health problem caused by the accident. The study team comprised more than 100 scientists, eight UN agencies and the governments of Russia, Belarus and Ukraine. [P][D][E][H][X]
Nuclear decommissioning In its first report, the UK Nuclear Decommissioning Authority estimates that £56bn will have to be spent cleaning up the UK's ageing nuclear power stations. This is £8bn higher than previously estimated. The NDA also wants to speed up the clean-up from 125 years to 25 years in order to reduce the risks to future generations. [P][X]
Fast ignition fusion On the argument that the urgency of finding alternatives to fossil fuels justifies pursing several approaches to thermonuclear fusion, physicists from seven European countries have put forward proposals for a new 735 million euro facility to study 'fast ignition' laser fusion technology. This approach was first demonstrated in Japan in 2001. Two separate lasers are used to compress and heat a small capsule of deuterium and tritium until the nuclei are hot enough to undergo nuclear fusion, producing helium and neutrons. [P][O]
Cheaper solar cells Scientists at Berkeley have proposed a way to control the distribution of contaminants in silicon, potentially opening up the use of cheaper, "dirtier" starting materials for making solar cells. They found that silicon with micron-sized clusters of impurities, spaced hundreds of microns apart, has four times better photovoltaic efficiency than silicon with the same impurity content distributed more finely in nanosized clusters. [P][E][J][M]
Roadmap for solar energy A report by the US Department of Energy sets out the basic research needed to bring solar energy to its full potential. Concepts include artificial "molecular machines" that turn sunlight into chemical fuel; "smart materials" based on nature's ability to transfer captured solar energy with no energy loss; self-repairing solar conversion systems; devices that absorb all the colours in the solar spectrum for energy conversion; far more efficient solar cells created using nanotechnologies; and new materials for high-capacity, slow-release thermal storage. Cross-cutting research directions include: coaxing cheap materials to perform as well as expensive materials; developing new solar cell designs that surpass traditional efficiency limits; finding catalysts that enable inexpensive, efficient conversion of solar energy into chemical fuels; and developing materials for solar energy conversion infrastructure, such as transparent conductors and robust, inexpensive thermal management materials. [P][J][M][N][O][T][W] |
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| [M] Materials, structures and surfaces | |
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Ultra-hard material A material harder than diamond has been created by researchers at the University of Bayreuth. Known as aggregated carbon nanorods (ACNR), the material was created by compressing carbon-60 buckyballs to 200 times normal atmospheric pressure, while simultaneously heating them to 2226 degrees C. The new material is made of tiny interlocking diamond rods. Each rod is a crystal that has a diameter of between 5 and 20 nanometres and a length of about 1 micron. The material, which could replace diamonds in industrial applications, is highly reproducible, according to the researchers, and they believe that it should be easy to mass-produce. [M][N][P][W]
Liquid magnetic state A novel material that may demonstrate a "liquid" magnetic state at extremely low temperatures has been discovered by Japanese and US researchers. The material, nickel gallium sulphide (NiGa2S4), was synthesized by scientists at Kyoto University. Its triangular arrangement of atoms appears to prevent alignment of magnetic "spins." The researchers have found that at any instant in time the material looks like a magnetic liquid, though it is not yet clear whether the spins actually fluctuate as in a liquid. The liquid magnetic state was predicted theoretically about 30 years ago, and may be related to the similar fluid way in which electrons flow without resistance in superconducting materials. [M][F]
Quantum critical superconductivity Strong magnetic fields normally destroy the superconducting properties of materials. However, physicists in France have discovered that the metal uranium rhodium germanium becomes a superconductor in the presence of an extremely strong field above 8 Tesla. This behaviour is associated with a quantum phase transition between two different magnetic states at a field of 12 Tesla. [M][F]
Tissue engineering Developments in tissue engineering mean that cells taken from animals could be grown directly into meat in a laboratory, according to an international team of researchers. [M][E][G][H]
Carbon nanotube fabric Australian and US researchers have produced nanotube fabric by drawing multiwalled carbon nanotubes into transparent sheets 5 cm wide and 1 metre long. A densified stack of 18 nanotube sheets that were orthogonally oriented to their neighbours had a strength of 175 MPa/(g/cm3). This compares well to the Mylar and Kapton films used for ultra light air vehicles. The researchers have also demonstrated potential applications of the sheets for polarized-radiation sources, flexible organic light-emitting diodes, transparent elastomeric electrodes, conducting appliqués, and in the microwave bonding of plastics. [M][A][D][I][N][O][P][V]
Super anti-fog coating Chemists at MIT have developed a superhydrophilic polymer coating that transforms opaque water droplets into smooth transparent sheets and that could be used to keep car windows, bathroom mirrors and spectacles from fogging up. The coating is composed of a three-dimensional matrix of negatively-charged, water-loving polymer chains, intermingled with a mixture of glass nanoparticles and tiny air bubbles. The resulting roughness increases the surface area of glass in contact with water, enhancing the attractive forces between the two and overcoming some of the surface tension. As a result, the droplets that form are flatter and eventually join up to form sheets. [M][N][O][V]
Warm ice Korean researchers have shown experimentally that water confined in a nano-sized gap can freeze at room temperature if an electric field of 1mV/nm is applied. It is believed that the electric field triggers the formation of ordered hydrogen bonding needed for crystallization. The results are surprising because the field strength is a factor 1000 lower than was predicted theoretically. If correct, the findings suggest that warm ice should appear on a range of confining surfaces, including the minuscule crevices in ordinary rocks, and might also routinely affect molecular-scale activities such as protein behaviour in cells and the operation of nanoscale tips used for fine-scale lithography. It might also be significant in nanofluidic devices. [M][G][J][N][S]
Nanotube dry adhesive US scientists have shown how to create a densely packed carpet of carbon nanotubes that functions like an artificial gecko foot, but with 200 times greater adhesion than a real gecko foot. [M][N][W] |
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| [E] Environment, transport and marine | |
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Consistent evidence for global warming According to a report by scientists at Yale and NOAA, errors caused by the sun's heat on instruments carried by weather balloons largely account for a key discrepancy, which has for a long time been used to cast doubt on the reliability of global warming models. The instruments on early weather balloons were more exposed to heating by the sun than those on later balloons. This difference masked the atmospheric temperature rise from global warming, and suggested that the troposphere in the tropics had actually cooled slightly since 1979. Allowing for this error, and also for the way that heat is released when moist tropical air rises and condenses into clouds, new climate observations and computer models now, for the first time, provide a consistent picture of global warming. [E][C]
Carbon loss from UK soil Analysis of soil samples gathered from across England and Wales over 25 years indicates that the warmer climate is causing soils to "exhale" large quantities of carbon dioxide, probably accelerating global warming. The researchers at Cranfield say that the findings, if extended to the whole of the UK, suggest some 13 million tonnes of carbon are being lost from British soils each year. Soils are a vitally important sink for carbon dioxide – twice as much carbon is wrapped up in soils as in Earth's vegetation or atmosphere. It is estimated that soils store 300 times the amount of carbon dioxide now released annually by burning fossil fuels. [E]
Sub-Arctic warming In the past four years, the whole western Siberian sub-Arctic region has started to thaw. The 11,000-year-old peat bogs, an area the size of France and Germany combined, contain billions of tonnes of methane, most of which has been trapped in permafrost and deeper ice-like structures called clathrates. [E]
Arctic warming The growth of vegetation in the Arctic, stimulated by warmer temperatures, could result in an additional climate warming of several degrees over the next few decades. As the number of dark-coloured shrubs in the Arctic tundra rises, the amount of solar energy absorbed could increase winter heating by up to 70 percent. [E]
Antarctic warming A new NASA-funded study finds that the predicted increases in precipitation due to warmer air temperatures from greenhouse gas emissions may actually increase sea ice volume in the Antarctic's Southern Ocean. This adds new evidence of potential asymmetry between the two poles, and may be an indication that climate change processes may have different impact on different areas of the globe. [E]
Survival of tropical species The most severe ecological impact of global warming may be in the tropics, even though the actual temperature rise will be much less than in high latitude regions. Organisms in the tropics do not experience much temperature variation because there is very little seasonality. As a result they appear to have very low tolerance. [E]
Permian extinction Scientists at NCAR have created a computer simulation showing Earth's climate in unprecedented detail at the time of the Permian extinction 251 million years ago in which up to 95 percent of marine species and 70 percent of land species died out. The work gives support to a theory that an abrupt and dramatic rise in atmospheric levels of carbon dioxide triggered the extinction. It demonstrates how rapidly rising temperatures in the atmosphere can affect ocean circulation, cutting off oxygen to lower depths and extinguishing most oceanic life. [E][C]
Oceans as a carbon sink Nitrogen is an essential nutrient for phytoplankton and other aquatic life. Biologists have long known that dead organic matter, as it decomposes in the ocean depths, releases nitrogen nutrients that drift upwards, cyclically fertilising the ocean's surface. However, a decade-long study at USC has shown that this is not the only mechanism and that nitrogen fixation from the atmosphere by marine organisms such as Trichodesmium plays a much larger role than has previously been supposed. Also, because nitrogen nutrients rising from the depths bring carbon dioxide with them, the nitrogen fixation from the atmosphere is probably the crucial factor in the amount of carbon dioxide absorbed into the oceans from the atmosphere. This suggests that if a way was can be found to boost the nitrogen fixation, the oceans might be able to absorb more carbon dioxide. [E][P]
Hurricanes and ocean temperature The number of Category 4 and Category 5 hurricanes has increased on average from 10 per annum in the 1970s to 18 per annum since 1990, according to a global study by Georgia Tech. The researchers say that it is likely that global warming, and the warmer ocean waters associated with it, are responsible for this increase, but the evidence is conflicting. Whilst hurricane intensity has increased, the number of hurricanes and the days with tropical cyclone activity on an annual basis have actually been in decline since reaching a peak in 1995. [E][D]
Rain models Existing forecasting models assume rain droplets fall through still air within a cloud. An international team has now developed an improved model that takes into account the turbulence within clouds, which can speed up droplet settling and increase the likelihood of rain. The model's results were checked against measurements from aircraft flying through different types of clouds. [E][C]
Controlled flowering Researchers in Sweden have made a breakthrough in understanding how plants control their flowering. They show how a small molecule that is formed in the plant leaves is transported to the shoot tips where it induces the formation of flowers. This new knowledge can lead to the development of tools to control the timing of plant flowering in agriculture and forestry. [E]
Vehicle pollution A UK study finds that childhood cancers are strongly linked to pollution from engine exhausts, particularly diesel. Exposure of a child in the womb and soon after birth to atmospheric pollutants is likely to be the critical period. [E][H]
Geodynamo The Earth's iron core consists of a solid inner core about 2,400 kilometres in diameter and a fluid outer core about 7,000 kilometres in diameter. The inner core plays an important role in the geodynamo that generates Earth's magnetic field, and an electromagnetic torque from the geodynamo is thought to drive the inner core to rotate relative to the mantle and crust. This differential rotation was first observed in 1996 and has now been confirmed by seismic data. [E][R] |
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| [R] Remote sensing and sensor systems | |
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Lunar prospecting Planetary scientists are using the high UV resolution of the Hubble Space Telescope to scan the Moon for mineral deposits that might indicate good sites for a potential lunar base. In particular they are trying to locate deposits of the mineral ilmenite (iron titanium oxide). It contains oxygen, which could be extracted for breathing, as well as hydrogen and helium absorbed from the solar wind. Heating the mineral would release the gases, which could then be used as a power source for the base. Iron in the mineral might eventually be used to produce construction materials, such as steel, for lunar buildings. [R][A]
Locating landmines Honey bees can, like dogs, be trained to sniff-out explosives, and US researchers are using them to locate landmines. The bees are tracked in flight using LIDAR. This is a very demanding LIDAR application because a bee hovers over a potential mine site for only a few seconds at the most, and the bees also fly close to the ground, making them hard to distinguish from vegetation. [R][O]
Ultrasound imaging Siemens has developed a new generation of micro-bubble contrast media for ultrasound imaging. Previously the micro-bubbles burst after their initial contact with sound waves and supplied a one-time image only. In the new media, the micro-bubbles remain in the patient's circulation for approximately 15 minutes. They enable physicians to detect tumours and small metastases in a highly reliable manner through blood circulation patterns. The new method is already being used in several European hospitals, particularly for diagnosing liver cancer and other liver lesions. [R][H][M][S]
Imaging within the brain Research at Stanford has demonstrated a promising, minimally invasive optical technique that can capture micron-scale images from deep in the brains of live subjects. The method, called two-photon microendoscopy, combines two-photon imaging and fibre-optic microendoscopy into one device that fits in the palm of the hand. [R][B][S]
Sleep spectrogram A new electrocardiogram technique could provide an inexpensive method to assess the stability and quality of sleep. It provides information that is not captured by conventional approaches to categorize non-REM (non-rapid-eye-movement) sleep into grades of depth. The researchers believe the technique can help understand the mechanisms of sleep control and diagnose sleep disorders, as well as being used to test the efficacy of sleep aids and other medications. [R][B]
Carbon dating DNA Researchers from the Karolinska Institute have found that, by exploiting the peak in atmospheric carbon-14 created by nuclear testing, carbon-14 dating techniques can be applied to DNA to measure the age of different types of cells in the human body. When above ground nuclear testing ended in 1963, the levels of atmospheric C14 had doubled beyond natural background levels. Since then, this level has halved every 11 years, producing detectable changes in levels of C14 in modern DNA. Many cells are recycled very quickly, including skin cells, blood cells and cells that line the gut. Other intestinal cells have an average age of 15.9 years, skeletal cells a bit more than a decade, and cells from the muscles of the ribs have an average age of 15.1 years. When looking into the brain cells, all of the samples taken from the visual cortex, the region responsible for processing sight, were as old as the subjects themselves, supporting the view that these cells do not regenerate. However, other brain cells were more recent. [R][B][G][H] |
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| [S] Sensor devices | |
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BEC ring gyroscope At team at UC Berkeley has nudged a Bose-Einstein condensate (BEC) of rubidium atoms into a circular racetrack 2 millimetres across, creating a particle storage ring analogous to the accelerator storage rings of high energy physics. The BEC storage ring could be used as a gyroscope to detect minute changes in rotation. If a ring could be created with two BECs travelling in opposite directions, the quantum interference pattern the two matter waves create would shift with rotation, allowing exquisitely sensitive detection of rotation for use in research or in navigation systems for satellites or aircraft. The BEC ring might also be used to study quantized circulation, which is seen in superfluids and superconductors. [S][A][F][M][R]
Biosensing and separation A new technique called "dynamic multiple equilibrium gradients" (DMEG) greatly increases the resolution of capillary electrophoresis. The advance makes it possible to detect the smallest traces of substances for biosensing. Because the system can be fine-tuned to separate specific substances and concentrate them at particular points as they move through the capillaries, it can also be used to create crystals. In this way it is possible, for example, to produce photosynthetic complexes for use in solar/photovoltaic cells. [S][M][P]
Prion sensor A new biochemical technique allows the reliable detection of the malformed proteins (prions) that cause Creutzfeldt-Jakob Disease (CJD). The automated test using a blood sample takes only a few days to complete. It has so far been tested in hamsters. If it works in humans, it could help to minimise the spread of prions in blood transfusions and organ transplants, and facilitate the diagnosis of prion diseases. Such blood tests would also allow the screening of animals before they enter the human food chain. [S][H]
Fibre-optic acoustic sensors Australian researchers have developed a fibre-based underwater acoustic detector which they claim is a hundred times more sensitive than current technology. It derives from research on detecting gravitational waves, and is based on a Fabry Perot cavity created by two Fibre Bragg grating mirrors written into the core of the optical fibre. The sensor should be valuable for oil and gas reserve monitoring, marine mineral exploration and deep sea surveillance. [S][E][R]
Uncooled infra-red imager Researchers at Northwestern University have demonstrated an uncooled 256 by 256 pixel infra red camera using type-II superlattice photon detectors made from InAs/GaSb. They have demonstrated the operation of type-II detectors all the way from 3 microns wavelength out to 32 microns, and believe these sensors will replace mercury cadmium telluride sensors. [S][J][R]
Soft tissue x-ray imager Conventional x-ray imagers exploit x-ray absorption. This works well for hard tissues, such as teeth and bone, but not for distinguishing between different types of soft tissue, such as normal and cancerous breast cells. European researchers have now demonstrated a practical x-ray imager that provides good 2- and 3-dimensional images of soft biological tissue by exploiting phase information. [S][R] |
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| [O] Optoelectronics, optics and lasers | |
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Active adaptive microscope Researchers from Rensselaer Polytechnic have unveiled an optical microscope design that they say overcomes the inherent trade-off between field-of-view and resolving power found in traditional instruments. Called an Adaptive Scanning Optical Microscope (ASOM), the design combines a high-speed steering mirror, a custom-designed scanner lens, a MEMS deformable mirror and imaging optics. [O][J][S]
Cheaper negative refraction Negatively-refracting materials are difficult and costly to produce, as they involve complex assemblies of intricately-shaped conducting components embossed on non-conducting platforms. UK and US researchers propose that negative refractive index materials could instead be produced much more cheaply by simply blending two granular substances together. Neither of the two granular substances can refract negatively by itself. However, the study predicts that a homogeneous mixture can refract negatively, provided the relative properties and proportions of the substances are chosen appropriately. [O][M]
Photonic quasicrystals Researchers from the US and the Netherlands have made the first three-dimensional photonic quasicrystal and confirmed its properties at microwave frequencies. Quasicrystals are of interest for making photonic band-gap structures that could be used in a variety of applications in computation and communication. The discovery could be used to develop new structures that would work in the same fashion as an elbow joint in plumbing by enabling light to make sharp turns as it travels through photonic circuits. [O][I][M][N]
Photonic crystal accelerator A team at MIT has used a photonic band-gap structure to accelerate electrons. This result could lead to a table-top particle accelerator that is capable of accelerating particles into the TeV range. [O][M][P]
Slow light A team of researchers from the Ecole Polytechnique Fédérale de Lausanne (EPFL) has successfully demonstrated, for the first time, that it is possible to control the speed of light – both slowing it down and speeding it up – in an optical fibre, using off-the-shelf instrumentation in normal environmental conditions. The method, which exploits Stimulated Brillouin Scattering and works at any wavelength, avoids the need for special media such as cold gases or crystalline solids, and provides a wide range of delays. The researchers say that this technology could take them far beyond just improving current telecom applications, and could be used to generate high-performance microwave signals for next-generation wireless communication networks, or used to improve transmissions between satellites. [O][I][R] |
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| [I] IT, communications, networking and secure systems | |
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4G cellphones 4G cellphones capable of receiving data at up to a gigabit per second while static have been demonstrated by NTT DoCoMo in Japan. In experiments, prototype phones were used to view 32 high definition video streams, while travelling in an automobile at 20 kilometres per hour. According to the company, the phones could receive data at 100 megabits per second on the move and at up to a gigabit per second while static. DoCoMo's current 3G phone network offers download speeds of 384 kilobits per second and upload speeds of 129 kilobits per second. The 4G tests used a method called Variable-Spreading-Factor Spread Orthogonal Frequency Division Multiplexing (VSF-Spread OFDM), which increases downlink speeds by using multiple radio frequencies to send the same data stream. [I][V]
Universal codec The convergence of consumer electronics and mobile communications, and the emergence of ubiquitous, heterogeneous network environments, are demanding universal standards for coding signals. At present, there is a plethora of different codecs, each optimised for specific signals, applications and hardware. As a result, networks formed from diverse and disparate devices, like mobile phones, PDAs and computers for example, cannot easily exchange media files. To tackle this, a team of European researchers has developed a prototype universal codec that will, if adopted, code any piece of recorded music or speech for any device. The bit-rate, or file size of each piece of music, is adapted for each receiving device. It can work for everything from mobile phones to broadcasting. [I][K][V]
Privacy protection Measures to protect the privacy of patients by removing precise geographical data could be hampering efforts to spot disease clusters and monitor the health effects of environmental pollution, according to researchers at Bath University. They propose how, by constructing virtual institutions in which software agents can analyse data, collaborating organisations could make raw data available for research without compromising the security of the information. [I][C][D][E][H][K]
Cyber security R&D The IT infrastructure in the US, including air traffic control systems, power grids, financial systems, and military and intelligence cyber networks, is highly vulnerable to terrorist and criminal attacks, according to the President's Information Technology Advisory Committee (PITAC). The White House-appointed expert panel has concluded that “the federal government needs to fundamentally improve its approach to cyber security". In its report in February 2005, PITAC recommended increasing the NSF budget for fundamental research in civilian cyber security by $90 million annually. That would amount to a four-fold increase for the NSF’s Cyber Trust program. The presidential panel also urged substantial increases for civilian cyber security R&D funding through the Department of Homeland Security and DARPA. [I][C][D][H][K][P][X]
Computer vulnerabilities NIST has launched a National Vulnerability Database (NVD) to make it easier for system administrators and other security professionals to learn about computer vulnerabilities and how to remedy them. The NVD is a comprehensive database that integrates all publicly available US government resources on vulnerabilities and provides links to many industry resources. NVD is built upon a dictionary of standardized vulnerability names and descriptions called Common Vulnerabilities and Exposures. Updated daily, NVD currently contains information on almost 12,000 vulnerabilities. [I][C][K] |
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| [K] Knowledge, information and technology management | |
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Location-based internet search The big portals and search engines are competing to provide local services and interactive mapping. With an eye to the future, Google has even launched Google Moon. [K][I][T]
Search engines Google's desktop search software is being overhauled to become a digital helper that reacts to what users do. The move is likely to intensify competition between Google and rivals Microsoft, Yahoo and AOL. The revamped software will suggest web links, personal documents and images that might be relevant to whatever someone is doing with their computer. [K][I]
Women in computing A study in 21 industrialised nations has found that, universally, women predominate in such traditionally female-typed fields as education and health and lag behind in stereotypically masculine fields. In computer science, male-to-female ratios vary from 1.79 in Turkey, on the low end, to 2.10 in the US, 3.10 in the UK, up to 6.42 in the Czech Republic. The researchers observe that those countries with the best female representation in computer science seem to have in common that their governments exert strong control over curricular trajectories and require substantial mathematics and science coursework. [K][I] |
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| [C] Computing, supercomputing, modelling and simulation | |
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Personalised virtual computer Users could soon carry their personal computer on their key ring. Researchers at IBM have developed a way to store a personalised virtual computer on a USB key, or any portable device with substantial storage space, like an MP3 player, allowing it to be carried from one PC to the next, without losing the user’s work. [C][I][K]
Requirements for quantum computing Researchers at Lawrence Berkeley and UC Berkeley have simulated the process by which a quantum computer could calculate to high precision the ground-state energies of water and lithium hydride. The results confirm that to exceed the limits of classical computing, quantum algorithms running with at least 40 to 100 qubits are needed. [C][M]
Quantum coherence Physicists at NIST have stored quantum information on single beryllium ions for 10 seconds, more than 100,000 times longer than in previous experiments with Be ions. Previously, the stored information was lost because the ions were affected by the slight variations in magnetic field in the electromagnetic trap holding the ions. The NIST team were able to overcome this problem by using a different pair of the ion's internal energy levels to represent 1 and 0. The advance improves prospects for making practical, reliable quantum computers. [C]
Nanotech device simulation Engineers at Purdue University have created a computer simulation tool that shows how current flows between silicon atoms and individual molecules. This will help researchers design "molecular electronic" devices for future computers and advanced sensors. [C][J][N][S] |
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| [W] Whole life engineering, manufacture and testing | |
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Software development In 2005, organizations and governments will spend around $1 trillion on IT hardware, software, and services worldwide. The size, and hence the risk of projects is increasing. Mega software projects, once rare, are now much more common, as smaller IT operations are joined into "systems of systems." According to the September issue of IEEE Spectrum, in the US alone the direct and indirect costs for failed and troubled software is at least $60 billion a year. Projects generally fail through a combination of factors: unrealistic or unarticulated project goals, inaccurate estimates of resources needed, badly defined system requirements, poor reporting of the project's status, unmanaged risks, poor communication between customers, users and developers, the use of immature technology, inability to handle the project's complexity, sloppy development practices, poor project management, stakeholder politics, and commercial pressures. [W][C][I][K][T][X]
Formal methods Formal software design methods have been in use since the 1970s. They can reduce software errors by two orders of magnitude or more. They are particularly useful for moderately complex software where very high integrity is essential. However, they are not a panacea for mega software projects. Using formal methods can take more time and require new skills, all of which can mean higher up-front costs for a client. Also, software engineers are usually not mathematicians, and they like to get on with coding rather than formal analysis. [W][C] |
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| [X] Systems, complexity and risk | |
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Network theory A small-world network is one where certain nodes, called hubs, have an unusually large number of connections, so that going through hubs one can reach any other node in just a few steps. The theory of "small-world" networks yields insight into innumerable real-world situations, including the Internet, power grid, epidemics and opinion making. Small-world networks exhibit critical thresholds, which play a key role in network failures or uncontrollable spread of diseases. Belgian research has now shown that it is possible to model these critical thresholds if one tunes the network hubs to be less influential on their neighbours than the ordinary nodes. [X][C][D][I][K]
Social and economic resiliency Societies today face novel challenges, including unprecedented rates of social and technological change, rapid urbanization, globalization, unpredictable natural disasters and the continuing threat of terrorism. Countries often find it difficult to respond to these challenges within their resource constraints and long-term goals. According to researchers at Arizona State, countries could individually and collectively achieve much better resiliency if they adopted a "systems approach", evaluating their policies and investments systematically, treating them as a portfolio, and focusing on "dual use" opportunities that not only respond to threats such as terrorism and natural disasters, but provide additional social and economic benefit and resiliency as well. [X][D]
Social conformity UK and US researchers have demonstrated that chimpanzees have a bias towards social conformity that has previously been considered to be a unique hallmark of human culture. [X][B]
Immune system model According to research at Rice University, the immune system has evolved a near-perfect balance for producing antibodies that are both effective against pathogens and unlikely to attack one's own tissue. The system has foregone evolutionary changes that would allow it to produce better antibodies in less time because the improved antibodies would be far more likely to cause autoimmune disease. The findings are based on a new model of the immune system that is the first to simulate the hierarchical nature of the body's immune response. The model confirms that chronic infections may lead to autoimmune diseases, such as arthritis, but finds that the length of the infection prior to onset of autoimmune disease is highly variable. [X][C][G][H]
Immune system stability In some severely injured patients, the inflammatory system can become unstable, leading to a whole-body response, including bloodstream infection (sepsis) and multiple organ failure. To understand this requires studying a system involving thousands of interacting genes. Scientists have now produced the genomic equivalent of a time-lapse movie, tracking the activity of thousands of genes through the course of body-wide inflammation. One counter-intuitive finding is that, of the 5,000 or so genes that fluctuated in response to bacterial endotoxin in the blood, more than half were reduced in their activity, causing the blood cells to be less metabolically active. This seems surprising, as one would expect genes required for healing to be turned up and for white blood cells to be more, not less, active. [X][G][H] |
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| [V] Virtuality and human-machine interface | |
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Quasi-virtual living It will soon be possible to inhabit a virtual world, even while out and about in the real one. US computer game company Artificial Life will shortly launch a massively multiplayer online role-playing game (MMORPG) for 3G phones. This will let players assume a virtual persona and travel through a futuristic cityscape, chatting and interacting with computer-controlled characters as well as other human players, and tackling puzzles that can be solved more easily through cooperation. [V][I][K]
Virtual mugging A man has been arrested in Japan on suspicion of carrying out a virtual mugging spree by using software "bots" to beat up and rob characters in the online computer game Lineage II. The stolen virtual possessions were then exchanged for real cash. [V][I][K]
PDA interface Handheld computing devices like PDAs and Tablet PCs are getting increasingly powerful. But without a keyboard, it is hard to exploit this potential. Existing methods that involve tapping out letters on a virtual keyboard, or using software to decipher hand-writing, or learning a kind of shorthand, all have limitations, as does speech recognition. IBM researchers have developed a new interface that uses geometric patterns traced across a virtual keyboard in a single fluid stroke. It can be used with a Qwerty keyboard or with IBM's experimental Atomik keyboard whose keys are arranged to maximise letter associations. [V][I][K]
3D displays Multiview and head-tracked autostereoscopic displays combine the effects of both stereo parallax and movement parallax to give 3D perception without the need for glasses. The best implementations produce a perceived effect similar to a white-light hologram. Usable systems have been available for a few years, and are being used in applications that exploit their novelty, including in some computer games and advertising, and also in applications where 3D depth perception is vital. This includes scientific and medical visualization of complex 3D structures, oil and gas exploration, and remote manipulation of robots in dangerous environments. However, because of their cost and because their 3D perceptual cues work only over a range of at most a few metres, it is unclear whether they will find wider markets. [V][C][T]
Artificial hand Scientists at Southampton University have developed a new ultra-light artificial hand that can mimic the movement in a real hand better than any currently available. It uses six sets of motors and gears so that each of the five fingers can move independently. This enables it to make movements and grip objects in the same way a real human hand does. It can be connected to muscles in the arm via a small processing unit and is controlled by small contractions of the muscles that move the wrist. [V][U]
Smelling chocolate Using fMRI, researchers have found that the smell of chocolate activates different brain regions according to whether the odour is introduced into the olfactory system through the mouth or through the nose. This is the first clear evidence that olfaction is a "dual" sense. The same effect was found with lavender, although the difference was less pronounced. [V][B]
Visual understanding Researchers at John Hopkins have confirmed experimentally that the brain does have special circuits in the visual centre that are constantly organizing what one sees into a provisional whole picture even as one's attention is focused only on one part of a scene. However, the brain can also fail to notice large changes in a visual scene - a phenomenon often exploited by magicians. Research at University College London has shown that the parietal cortex, which is the area of the brain responsible for concentration, is also critical to the brain's ability to detect changes. This is probably a major reason that listening to a car radio, or conversing over a mobile phone, can affect perception whilst driving. [V][B]
eAccessibility The European Commission has adopted a communication on eAccessibility, designed to encourage the development of information and communication technologies (ICTs) that are accessible to all, including people with disabilities and the elderly. The communication proposes the use of accessibility requirements in public procurement and accessibility certification. The first implies that public agencies in Europe would require all ICT products and services that they buy to be accessible. With public procurement accounting for 16 percent of total GDP in Europe, such a move would help to create a larger market for accessible ICTs. [V][I][K][T] |
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| [B] Brain research and human science | |
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Enhanced creativity It has long been thought that people with schizotypal personalities may be more creative than either normal people or fully schizophrenic people. Research at Vanderbilt University has now provided experimental evidence for this by means of creativity tests and monitoring the activity in the subjects' prefrontal lobes using near-infrared optical spectroscopy. The brain scans showed that all subjects, whether normal, schizotypal or schizophrenic, used both left and right brain hemispheres for creative tasks. However, in the schizotypes, the activation of the right hemisphere was dramatically greater, supporting the idea that schizotypes and other groups prone to psychoses draw on the left and right sides of their brains differently from the average population, and that this bilateral use of the brain may be related to their enhanced creativity. [B][K]
Placebos and pain perception Experiments using fMRI indicate that the perception of pain depends strongly on expectation. In trials on 10 volunteers with ages from 24 to 46, the expectations of lower pain yielded about as much relief from physical pain as researchers had previously reported for morphine. In contrast, expectations of harsher pain than was actually delivered did not magnify volunteers' self-reported pain. These results add to a growing body of evidence that placebos work via the brain mechanisms underlying pain. Other US researchers have shown using PET scanning of the brain that placebos generate the production of endorphins in four parts of the brain known to be involved in processing and responding to pain. The results show the benefit of placebos and also of psychological interventions to prepare patients for painful medical treatments by recasting their expectations more positively. [B][H]
Addiction Obesity and drug addiction appear to be different problems, but researchers have found that the two conditions have several neurological similarities. Food cravings and drug cravings, and the reinforcement of addictive habits, all produce activation of the same brain areas. This is leading to the development of new drugs and therapies intended to fight both obesity and drug addiction. [B][H][T]
Alcohol abuse Alcohol abuse is now thought to cost the British economy £30bn a year, and alcohol dependency rates in the UK are amongst the highest in Europe, at 7.5 percent of British men and 2.1 percent of British women. According to evaluations in the British Medical Journal (BMJ), two treatments for reducing alcohol dependency – motivational enhancement treatment and social network therapy – are very cost-effective and deserve much wider use in tackling the UK's alcohol problem. [B][H]
Combat trauma A series of studies, including analysis of the health records of 18,000 US veterans and of Israeli veterans from the combat in Lebanon, indicates that soldiers suffering psychological traumas years after serving in a war also experience poorer physical health. They are more likely to develop heart disease and cancer in later life than fellow war veterans. The effect of chronic stress on the immune system may be a major cause. [B][H][D]
Protein aggregation diseases Scientists at NIAID have found that small prion clusters are much more infectious than large ones, and that there also is a lower size limit below which infectivity falls to zero. The findings are consistent with the recently emerging evidence that, in many of the neurological protein aggregation diseases, small, misfolded clusters are more damaging than large clusters. This could mean that treatments designed to break apart large accumulations of plaques in the brain might do more harm than good by releasing the most infectious prion particles. Researchers at Brown Medical School researchers have also found that prions can convert healthy protein into abnormal protein astonishingly quickly. [B][H]
Alzheimer's vaccine A new nasal vaccine for Alzheimer’s disease has cleared plaques from the brains of affected mice and will be tested in humans in 2006. [B][H]
Diet and brain ageing A long-term study by the US National Institute of Aging indicates that adults who eat the daily recommended allowance of folates significantly reduce their risk of developing Alzheimer's disease. Folates are B-vitamin nutrients found in oranges, legumes, leafy green vegetables and folic acid supplements. Recent Dutch research has found that adults who took 800 micrograms of folic acid daily had significant improved memory test scores, giving evidence that folates may slow cognitive decline. [B][H]
Nerve regeneration The same family of chemical signals that attracts developing sensory nerves up the spinal cord toward the brain also serves to repel motor nerves, sending them in the opposite direction, down the cord and away from the brain. Coupled with emerging stem cell technology, this knowledge of how to guide nerves to their target provides the most promising approach to regenerating nerves. [B][H]
Nerve stem cells The world's first pure nerve stem cells made from human embryonic stem cells has been created by scientists at the Universities of Edinburgh and Milan. The researchers overcame the previous problem that neural stems cells grown in vitro tended to differentiate automatically into more specialised cells. Now that nerve stem cells can be cultured successfully, it is hoped that they can lead to new treatments for diseases such as Parkinson's and Alzheimer's. [B][G][H] |
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| [H] Healthcare and medicine | |
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Treating inflammatory diseases The challenge in developing drugs for treating inflammatory diseases, including asthma, arteriosclerosis and arthritis, is how to prevent the immune system attacking normal body tissues, whilst maintaining its ability to deal with viruses and bacteria and avoiding cumulative side effects. By studying how viruses fight the immune system, researchers are identifying proteins that can switch the immune response off and on. Other researchers are identifying how proteins can exert overlapping anti-inflammatory effects and be dramatically more effective in combination than singly.This raises the possibility that using several drugs in combination might make them effective at much lower doses and thereby avoid side effects. [H][G]
Preventing immune response Recent experiments at Imperial College suggest that it may be possible to use regulatory T-cells to stop the immune system responding to foreign transplants. Regulatory T-cells keep other immune cells in check, and prevent them from attacking the body's own tissues. The technique could make tissue grafts invisible to the immune system, and would allow transplant recipients to circumvent the many side effects of immunosuppressive drugs. [H][G]
Preventing immune response Spanish researchers have successfully developed in mice a cellular therapy for two major autoimmune diseases: rheumatoid arthritis and multiple sclerosis. The scientists succeeded in making the symptoms disappear and inducing a reversion of the degenerative process. The therapy involves injecting dendritic cells which generate regulator T cells that reduce the auto-immune response. The technique appears to be very promising, but unfortunately such 'customized personal cellular therapy' would currently be prohibitively expensive for widespread use. [H][G]
Restoring the immune system The immune system deteriorates with age, and can be further damaged by severe infections and by chemotherapy and radiotherapy. Australian scientists have developed a technique to restore the immune system by revitalising the thymus using a common hormone. The thymus produces the T cells required to fight infection, but it shuts down from early adulthood. The researchers believe that restoring the immune system may provide a new approach to treating cancer and may work in many other severe clinical conditions such as HIV/AIDS. It may also boost the effectiveness of vaccines against cancer and infections. [H]
Mitochondria and immunology Mitochondria were thought to be concerned solely with energy production in a cell and with apoptosis. However, research at the University of Texas has discovered a mitochondrial protein that is vital to the immune system's ability to fight off viral infections. This opens up a new avenue of research in immunology. The researchers believe that the protein, named Mitochondrial Anti-Viral Signalling protein (MAVS), may play a role in coordinating cell death and immune response. [H][G]
Better TB vaccine Around one third of the world's population is infected with tuberculosis. The infection is initially dormant, but in about ten percent of cases, it erupts into open, contagious tuberculosis. A vaccine with high efficacy is urgently needed, as drug resistant TB is becoming widespread. The current BCG vaccine protects children against certain forms of TB, but gives no protection from pulmonary tuberculosis in adults, which is the most frequent form of the disease. The problem is that, in the body, the BCG bacteria become hidden from the immune system inside so-called phagosomes. By inserting a gene for a protein that causes perforation of the phagosomes, researchers at Max Planck have now produced a vaccine that gives protection against pulmonary TB and aggressive multi-drug-resistant forms of TB. Canadian researchers have found that the speed at which TB develops depends on a gene NRAMP1, which is involved in many illnesses including leprosy and rheumatoid arthritis. [H][D][G]
Xenotransplantation Following astonishingly successful trials in primates, it is expected that the US FDA will approve human trials of a treatment for Huntington's disease that involves injecting live cells from pigs into a patient's brain. The pig cells come from the lining of a brain structure known as a choroid plexus. They have a nurturing role, mopping up toxins, producing cerebrospinal fluid, and secreting a range of hormones and proteins called neurotrophins that are essential for brain cell function and protection. In Huntington's disease, there is a significant reduction in these chemicals. [H][G]
Foetal cell bandage A Swiss research team has found that the application of a biobandage containing a small number of foetal cells can dramatically improve the healing of the wounds of young burn victims. Trials on adult burn victims are planned. [H]
Foetal stem cell therapy During pregnancy a small number of foetal stem cells stray across the placenta and into the mother's bloodstream, a phenomenon called microchimerism. Researchers in Singapore have now shown, in mice, that these cells can colonise the brains of mothers. If the finding is repeated in humans, it could open up new, safer avenues of treatment for brain damage. A big potential advantage of using foetal cells as a treatment is that they could simply be injected into the bloodstream and left to find their own way into the brain. This would make it possible to treat conditions with diffuse injury, such as Alzheimer's disease. However, it is known that in some cases microchimeric foetal cells can also aggravate immunological diseases. [H][B][G] |
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| [G] Genomics, biotechnology and bioinformatics | |
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Controlling stem cell differentiation Scientists at Imperial College have found how to make human embryonic stem cells differentiate into lung cells - a step that could lead to the growing of human lungs for transplantation. [G][H]
Creating stem cells Researchers have found that fusing adult somatic cells with embryonic stem cells genetically reprogrammed the adult cells. The new cells grew into tight, round colonies characteristic of embryonic stem cells, they could multiply indefinitely, and they differentiated into the three basic embryonic tissue types, both in the lab and when transplanted into mice. The cells still contained two sets of chromosomes, and it is not clear how difficult it may be to remove the adult chromosomes. However, the approach could become an alternative to somatic cell nuclear transfer (SCNT), a method that is currently used to produce human stem cells, and that involves transferring the nuclei of adult somatic cells into oocytes whose nuclei have been removed. Understanding how the reprogramming process works may make it possible to directly turn adult cells into embryonic cells without using embryos. [G][H]
Stem cell pluripotency Researchers at Whitehead Institute have found that three proteins, Oct4, Sox2 and Nanog, are the master regulators that maintain the pluripotent state of embryonic stem cells, silencing genes that are waiting to create the next generation of cells. As the embryo develops, Oct4, Sox2, and Nanog are inactivated, allowing differentiation. Understanding these processes is fundamental for turning stem cells safely into the right tissues for therapeutic use, and also for safely culturing stem cells to avoid cancer risks. [G][H]
Stem cells and cancer Researchers at John Hopkins have found that stem cells cultured for long periods can develop genetic changes in areas known to be involved in human cancers, and also changes in their mitochondrial DNA that could affect metabolic function, and in their DNA methylation that controls which genes are “switched on or off”. The link between stem cells and cancer has also been identified by European researchers, who have shown that disrupting the stem cell genes that control the fates of daughter cells can lead to cancer. [G][H]
Umbilical cord stem cells Hopes for treating disease with stem cells from umbilical cord blood has received a major boost following the discovery of primitive cells with clinical potential matching that of embryonic stem cells (ESCs). The newly discovered human cells, named “cord-blood-derived embryonic-like stem cells” or CBEs, are not quite as primitive as embryonic stem cells, which can give rise to any tissue type of the body. But they appear to be much more versatile than adult stem cells. To make large enough quantities of the stem cells to repair tissue damage in patients, the researchers are using new microgravity technology, originally developed by NASA for the International Space Station. [G][A][H]
Mammalian genome complexity Three years ago the DNA of the mouse was completely sequenced. An international team of over 100 scientists has been attempting since then to isolate and analyse the entire messenger RNA (mRNA) transcripts in the mouse. The results appear to overturn the traditional doctrine that each mRNA contains the blueprint for precisely one specific protein. More than 60 percent of all the mouse mRNAs are not protein blueprints at all. Their function remains a complete puzzle, but they must be important because they have been accurately conserved by evolution. There are also far more mRNAs than genes, indicating that in mice the individual genes may produce many different proteins. This may answer the big riddle of why mammals need only about twice as many genes as simple organisms such as threadworms. [G][X]
Decoding gene function The European Union has approved funding of a three-year research programme designed to test the function of almost every gene in the mouse genome. The €13 million project proposes to generate 20,000 mutations in mouse embryonic stem cells and make them available to researchers worldwide. [G]
Exploiting transposons Genetic elements, called transposons, move from place to place in the genome and allow DNA to be inserted or relocated. Bacteria swap antibiotic-resistance genes using transposons. Scientists have tailored this natural gene shuffling technique to insert genes and mutate genes. This has proved valuable for research in fruit flies and other simple organisms, but has not worked well for vertebrates and mammals. A collaborative project between American and Chinese researchers has now overcome this problem by using a transposon called piggyBac that was originally derived from the cabbage looper moth. PiggyBac inserts itself randomly into the DNA, but it most often locates in genes, making it useful for mutating genes and thus revealing gene functions. PiggyBac also provides a potential new vehicle for human gene therapy. [G]
Anti-ageing therapy The Klotho gene is known to affect ageing in humans, and strongly affects lifespan in mice. US researchers have now found that the Klotho protein increases resistance to insulin. This is known to increase lifespan in a wide range of animals, including worms, fruit flies and mice. Whether therapies based on Klotho can significantly extend human lifespan without serious risk of diabetes is not clear, however. The human environment is much more complex than the idealised environment of laboratory animals. Thus, although caloric-restriction is well known to dramatically increase lifespan in laboratory mice, the effect appears to be very much weaker in humans, according to the latest analysis. [G][H]
Human evolution The human brain is still evolving rapidly, according to research at Chicago University, which has studied two genes linked to brain size. For each gene, one class of variants has arisen recently and has been spreading rapidly. One emerged about 37,000 years ago and now shows up in about 70 percent of present-day humans. The second arose about 5,800 years ago and is now present in about 30 percent of humans. These time spans are extraordinarily short in evolutionary terms and indicate very intense selection pressure. The researchers do not yet know precisely what evolutionary advantage the variants provide, or how far other genes affecting the human brain may also show rapid evolution. [G][B]
Chimpanzee genome The genome of man's closest living relative, the chimpanzee, has been released by an international consortium of scientists. It consists of 2.8 billion pairs of DNA letters and is extremely similar with the human genome; 29 percent of genes are absolutely identical. Cross-species comparison identified six DNA segments in people that appear to have been strongly shaped by natural selection over the past 250,000 years. Gene functions in these regions are largely unknown. An interesting finding from comparing human, chimpanzee and rhesus monkey genomes is that in 37 instances, retroelements (or jumping genes) present in Rhesus monkeys have been deleted during the evolution to chimps and humans. Previously it has been thought that insertions of retroelements, once established in a population, are irreversible and are maintained throughout evolution. [G][B]
Rice genome Members of a 10-nation International Rice Genome Sequencing Project (IRGSP) have produced a highly accurate or "finished" map-based DNA sequence of the entire rice genome. Rice feeds more than half of the world's human population, and it is estimated that the agricultural yield of rice will need to be increased by some 30 percent over the next two decades to meet projected increased demands. [G][E] |
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| [N] Nanotechnology and molecular technology | |
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Nano-shuttle A team of UK, Dutch and Italian scientists has exploited Brownian motion to enable a molecular engine to propel small droplets of liquid across flat surfaces and even up 12 degree slopes against the force of gravity. They used a gold surface covered with specially engineered molecules. When stimulated by ultra-violet light, a chemical reaction in one part of each molecule causes it to repel another part, making the molecules change their position. This alters the surface tension of a droplet of liquid placed on the gold surface and in this way produces enough energy to propel the droplet. The researchers believe this mechanism could lead to the development of artificial muscles and of 'smart' materials that change their properties in response to a stimulus. [N][H][M][S]
Nanohelix materials A previously unknown zinc oxide nanohelix structure could provide a new building block for creating nano-devices, including sensors, transducers, resonators and other devices that rely on electromechanical coupling. The nanohelix structure is based on a superlattice composed of alternating single-crystal "stripes" just a few nanometres wide. It is part of a family of nanobelts – tiny ribbon-like structures with semiconducting and piezoelectric properties – that were first reported in 2001. The nanohelices, which get their shape from twisting forces created by a small mismatch between the stripes, are produced using a vapour-solid growth process at high temperature. [N][J][M][S]
Magnetic nanocarbon Carbon can be made magnetic by introducing defects and irregularities that produce electrons that are not paired with other electrons. Researchers at Rensselaer Polytechnic have developed a technique to make diamond nanoparticles magnetic by bombarding them with clusters of atoms. Magnetic nanocarbons are of interest for high-density memory devices and quantum computers, and may also have potential for magnetic resonance imaging (MRI) and the targeted delivery of drugs to specific parts of the body. [N][H][J][M][R]
Nanowire stability Creating stable nanowires is of vital importance for nanoelectronics. US scientists have shown theoretically that solitons can propagate from one end of the wire to the other, causing thinning and eventual breaking. The formation of solitons depends on the surface tension and the quantum force that holds the wire together. The findings explain why noble metals, such as gold and silver, tend to create longer-lasting nanowires than sodium or other alkali metals. It indicates that copper should be the best metal for nanowires because of its large surface tension. [N][J][M]
Inorganic nanotubes Carbon dominates nanotube technology. However, there is also a wide range of nanotubes made from inorganic materials, many with intriguing properties quite different from those of carbon. Nanotubes made from transition-metal chalcogenides, oxides, and halides have all been synthesized, as well as mixed-phase, metal-doped, boron-based, silicon-based, and pure metal nanotubes. [N][J][M][O][P][S][T]
Nanocrystal production Researchers in China have come up with a “general strategy” for creating nanocrystals. Their phase transfer and separation technique can produce nanocrystals of metals, metal oxides, composite oxides, semiconductor and conducting polymers, including nanocrystals that are magnetic, dielectric, fluorescent and have optoelectronic or biomedical properties. [N][J][M][O]
Nanofabrication A new technique called microdisplacement printing makes possible the highly precise placement of molecules during the fabrication of nanoscale components for electronic and sensing devices. The new technique is based on a widely used patterning method known as microcontact printing. Both methods involve "inking" a patterned rubber-like stamp with a solution of molecules, then applying the inked stamp to a surface. [N] |
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| [J] Microelectronics, MEMS and spintronics | |
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Phase-locked nano-oscillators Two teams of US researchers have shown that nano-scale magnets can be made to oscillate in phase when they are positioned close to one another. The nanomagnets were built from two magnetic films of different thicknesses separated by a non-magnetic layer, and patterned using standard semiconductor processing technology to produce magnets less than 100-nm across. The oscillation frequency could be tuned from a few GHz to several tens of GHz by varying the current or by applying an external magnetic field. The devices might replace bulky and expensive phase-locked components in mobile phones and radar systems, and might also serve as tiny receivers that would enable microwave interconnect between computing chips. A phase-locked array should produce microwatts of power, scaling as the square of the number of devices. [J][C][I][N][R][S]
3D spintronic nanochips Researchers from Imperial College London, Durham University and the University of Sheffield have developed a new computer chip architecture based on 3D spintronic circuits, which they claim will enable large amounts of data to be stored in small volumes. The chip uses a complex interconnected network of nanowires, with computing functions and decisions performed at the nodes where they meet – a similar approach to neurons and axons in the brain. Currently the memory chips of mobile phones have a very limited capacity, making it impossible to store the videos that the new generation of phones can record. The new architecture could potentially increasing memory capacity to around 100GB, according to the researchers. [J][I][K][S][V]
Fluid FET By chemically modifying a silicon nanotube, researchers at UC Berkeley have created a fluid-based transistor that can conduct either positively or negatively charged ions dissolved in solution. As in ordinary field-effect transistors, the voltage on a "gate" electrode controls the flow of charge - in this case the flow of ions through the water-filled tube. The technology might be useful in highly sensitive biological sensors or in fluid-based "computer chips". [J][N][S]
Carbon nanotube diode Research at GE has shown that carbon nanotubes can make perfect p-n junction diodes, with an "ideality factor" of one. The diodes could have applications in electronics, sensors and photovoltaics. [J][N][P][S]
Y-shaped nano-devices Y-shaped nanotubes might become a common component in ultra small electronic circuitry. Scientists at UCSD have shown they can control current through the Y-junction by applying a voltage to its stem. The structures could have applications in transistors, logic devices and higher harmonic-frequency generation. [J][N] |
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