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Top Stories in Science
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March 2004 Issue |
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| [D] Defence and security |  |
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Tony Blair in a speech on the terror threat has argued that terrorism and weapons of mass destruction are two sides of the same coin and that they will inevitably come together if the threat is ignored. This, he said, requires a different philosophy in international relations from a traditional one that has held sway since the treaty of Westphalia in 1648; namely that a country's internal affairs are for it and you don't interfere unless it threatens you, or breaches a treaty, or triggers an obligation of alliance. It also requires tackling poverty in Africa and justice in Palestine as well as being utterly resolute in opposition to terrorism as a way of achieving political goals. [D] According to the UK's rail regulator, the railways will remain vulnerable to the sorts of attacks seen in Madrid and it would not be practical and affordable to introduce airport-style security to the rail network. [D][E][R] The head of the UN nuclear watchdog has echoed the call by President Bush for better international co-operation to halt the spread of nuclear weapons. China, Japan, Pakistan and India have all given their support. [D][P] Figures from the UN show that the number of people seeking asylum in industrialised countries fell by 20 percent in 2003 compared to 2002, and by 22 percent in the EU. [D] The International Narcotics Control Board has reported that drug dealers are increasingly using the internet to market narcotics and mind-altering drugs. It has called on governments to crack down on the illicit trade in controlled drugs over the internet. [D][H][I] Biodefence research at Dstl in the UK and at two US laboratories has shown that lytic bacteriophage, viruses that specifically target and kill bacteria, can be used as environmentally friendly decontaminants, replacing harmful chemicals like chlorine dioxide in cleaning up areas exposed to anthrax spores. The research suggests it should for possible to decontaminate soil by the co-administration of lytic bacteriophage and spore germinants. [D][E][H] Researchers at the University of Chicago have found that a drug clinically approved for treating chronic hepatitis B can also blocks the action of oedema factor, one of the two deadly toxins produced by anthrax. In the early stages of anthrax infection, oedema factor disrupts the immune response, allowing the bacteria to spread and produce more toxins. Subsequently, oedema factor causes massive tissue damage, including the black necrotic lesions which give the disease its name from the Greek for coal. [D][H] A drug which is used to treat hepatitis C and which has no side effects, may prove useful against severe acute respiratory syndrome (SARS). Trials in monkeys show that it eases the symptoms and reduces infectivity. [D][H] A device that combines an electrical field with soft X-rays and smart catalysts can capture and destroy bioagents such as the smallpox virus. Tests using non-potent polio virus achieved 99.9999 percent destruction efficiency. [D][H] Existing live smallpox vaccine can cause complications that kill one in a million recipients and cause serious illness in one in every 100 thousand. A new computer simulation of smallpox attack on the US shows that the need for mass vaccination can be avoided if the containment can be started quickly. Containment of infected individuals in their homes or in hospitals is more important than vaccination in the early stages of an outbreak. Mass vaccination might also be made safer by using a weaker vaccine, according to studies by the US NIAID. [D][C][H] An experimental vaccine that can be applied directly to the skin or via a patch protects mice from lethal exposure to aerosolised ricin, according to research presented at the ASM Biodefense Research Meeting. [D][H] Several research teams are trying to genetically alter the H5N1 bird flu virus to make it highly infections to humans. Their purpose is to try to understand better what causes flu viruses to become dangerous and specifically to estimate the risk that the current H5N1 virus might lead to a pandemic. The research is controversial because of the risk that genetically altered viruses might escape and spread or that the knowledge of how to create a pandemic virus might be used by bioterrorists. [D][G][H] A drug, Relenza, that is used to treat flu has been shown to be effective against the current H5N1 avian flu strain. Tests showed the drug was as effective at stopping H5N1 from multiplying as it was against other strains of flu that affect humans. [D][H] Russia claims that it has developed and test-launched a new ballistic missile technology that can beat any defence system. [D][A] |
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| [A] Aeronautics and space | |
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Nearly 3000 new combat aircraft will be built in the next decade according to a recent report, which shows the market recovering from the slump of 2002 when only 159 combat aircraft were built. [A][D] The plane in which adventurer Steve Fossett hopes to fly non-stop around the world without refuelling has begun its test programme. [A] The next launch of the Shuttle has been delayed to 2005 because of work into air flow around the external fuel tank. However, it may be possible to keep the Hubble telescope operating by using robots to service it until a Shuttle repair mission becomes feasible again. [A][U] The ESA Rosetta mission has launched successfully on its journey of 7 billion km to chase and land on Comet 67P/Churyumov-Gerasimenko in 2014. Its journey will take it around the Sun four times, around Mars once (in 2007), the Earth three times (in 2005, 2007 and 2009), and into the asteroid belt twice. [A] New measurements from Mars Express suggest the upper Martian atmosphere can be far less dense than previously thought. This could have been fatal for the Beagle 2 lander because it relied on the atmosphere's braking effect to trigger the release of its parachute. [A] After the enthusiasm sparked by Beagle and the Mars rovers, ESA is being lobbied to put landers on some of its upcoming missions. [A][U] Last November astronomers at the Mount Palomar Observatory spotted what may qualify as the tenth planet in the Solar System. The object has been named Sedna, after the Inuit goddess of the ocean. It is the largest body orbiting the Sun to be discovered since Pluto was spotted in 1930, and is similar to Pluto in size, with a diameter of around 2000 km. It has a highly elliptical orbit, almost like that of a comet. [A][R] |
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| [U] Unmanned vehicles and robotics | |
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The NASA rover Spirit has found signs of past water at its landing site. It drilled holes into a volcanic rock and found that water had formed small holes and left mineral deposits. The rover Opportunity, on the other side of Mars, has shown that the rocks at its landing site in Meridiani Planum were once in contact with substantial amounts of liquid water - they were modified in water and may have been precipitated in water. The presence of jarosite, an iron sulphate that forms only in the presence of water, suggests that an acid-rich lake or hot-spring environment might have existed there. NASA scientists say that this demonstrates unequivocally that Mars once had the conditions to support life. [U][A] The two Mars rovers, Spirit and Opportunity, are performing far better than NASA expected and may work for up to 240 days, about 150 more than the mission team had originally projected. This is fortunate because the crater in the immediate vicinity of Spirit now looks much less promising than previously thought. The longer mission duration should enable Spirit to travel about 2.5 km to reach a complex of hills that have clear variations in colour and composition and show strong suggestions of rock layering. [U][A] The Berkeley Lower Extremity Exoskeleton (BLEEX) is part of a DARPA venture to help foot soldiers carry heavier loads over even longer distances, by connecting robotic supports to their legs to reduce the load. It could also assist medical personnel carrying wounded people or fire fighters in hauling heavy equipment up flights of stairs. Importantly, the user needs no joystick, keyboard or buttons to operate it, leaving hands free for other tasks. [U][B][D][H][M][V] A metre-long robotic arm, called Flexibot, has been developed to help disabled people feed themselves, brush their teeth, shave, and even put on make-up. The arm moves around by flipping end over end from one docking station to the next. It can dock with a wheel chair and disabled users can control the arm by blowing down a straw or pressing a single button. [U][H][P][V] Research at UCLA funded by NASA has produced a silicon microrobot 50 microns wide that is powered by a cord of living heart muscle fibres. The microrobot is able to crawl around fuelled by a simple glucose nutrient. NASA hopes swarms of crawling "musclebots" might help maintain spacecraft by plugging holes made by micrometeorites. Another potential application is for muscle-based nerve stimulators that could enable paralysed people to breathe without the help of a ventilator. [U][A][B][M][N][P][V] A robot that can "print" houses is to be trialed by the construction industry. Working directly from an architect's computerised drawings, it uses a computer guided nozzle to squirt successive layers of concrete on top of one another to build up vertical walls and domed roofs. Two trowels attached to the nozzle move to shape each layer as it is deposited. [U][E][M] |
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| [P] Propulsion and energy | |
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Rolls-Royce has delivered the first of its Trent 900 engines for the Airbus A380 "super-jumbo" due to enter service in Spring 2006. The Trent 900 will power 48 percent of the A380s ordered to date. Pratt & Whitney engines will power the others. [P][A] A chance discovery has transformed an engine intended for speedboats into a powerful firefighting tool that douses flames with jets of water mist. Tests indicate that the device has great potential for putting out blazes, including in ships, aircraft and buildings. The UK company that has developed the device believes it may also be useful for neutralising chemical spills or for disinfecting buildings or people after a biological or chemical attack. [P][D][E] The annual bill for treatment of domestic wastewater in the US is currently about $25 billion. Researchers at Pennsylvania State University have developed a microbial fuel cell that biodigests sewage and other household waste and generates electric power from it. [P][E] According to the UK Department of Trade and Industry, wind power on-shore and off-shore can by itself deliver almost all of the required growth to meet the UK's 2010 renewable energy target. Wave power machines connected to an underwater electrical socket could also be providing power to the grid by 2006 according to proposals by the Regional Development Agency in the SouthWest of England. [P][E] Researchers at the University of Minnesota say they have found several methods to cheaply turn industrial ethanol into hydrogen suitable for fuel cells. They believe that the process could potentially produce electricity at around four cents per kilowatt-hour, rivalling the costs of conventional electricity. The hydrogen produced is only about 50% pure and is only suitable for solid oxide fuel cells. These operate best at very high temperatures and are suitable for stationary power generation rather than for vehicle fuel cells. The US produces about 2.8 billion gallons of industrial alcohol a year by fermenting plant matter such as corn. [P][E][M] President Bush has rejuvenated a US federal R&D programme for clean coal and coupled it with pushing towards a hydrogen economy. The aim is to achieve zero-emission power generation based on integrated gasification combined-cycle technology (IGCC). With conventional pulverised-coal generation plants, carbon dioxide makes up about 10 percent of the flue gases. With IGCC, the carbon dioxide concentration will be 90 percent making it ten times cheaper to collect. The plan is to dispose of the carbon dioxide by injecting it deep underground. [P][E][T] Oil-free, high-speed compressors operating downhole could enable more gas to be extracted from gas fields. [P] The highly controversial claim that nuclear fusion can take place inside tiny imploding bubbles of acetone has received support from further experiments in which, it is claimed, the neutrons emitted show the right energy and their quantity matches the amount of tritium detected. [P][M] |
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| [M] Materials, structures and surfaces | |
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By using a zirconium metal complex to add hydrogen atoms to nitrogen, a team at Cornell has found a way to convert nitrogen into ammonia without needing high temperatures or high pressure. The new process is unlikely to replace the Haber-Bosch industrial process for making ammonia, but it may be useful in making high added-value nitrogen chemicals, such as hydrazines for rocket fuels or fine chemicals for drug synthesis or dyes. [M][P] In high temperature superconductors made with layers of copper oxides sandwiched between insulating filler material, the critical temperatures rises as the number of layers increases from one to three. However, it then falls as the number of layers is increased further. According to researchers at the University of Toronto a key factor is charge imbalance between the multiple layers, and if a way can be found to affect the charge imbalance, this could lead to materials with higher critical temperatures. [M][P] Theorists have put forward many theories to explain high-temperature superconductivity in materials containing layers of copper oxide. Experimenters from McMaster University and Brookhaven National Laboratory have now ruled out two of these theories and presented new evidence that magnetic correlations between pairs of electrons is responsible. Research at the University of Illinois has also shown that two types of electron organisation - coherent motion and spatial organisation - operate in mutual competition. [M][F] Researchers at Trinity College Dublin have confirmed earlier indications that carbon nanotubes can become magnetised when placed in contact with a magnetic material. This opens new scope for magneto-electronics. The researchers calculated that the average room temperature magnetisation in the nanotubes is about 0.1 Bohr magnetons per carbon atom. By comparison, the figure for iron is 2.2. [M][J][N][S] An organic molecule has been discovered that has three unpaired electrons in its ground state, breaking Hund's rule. This could open the way to developing new non-metallic magnets made from polymers and hydrocarbons. Until now, the only molecules that broke Hund's rule were ones containing transition metals. [M] The immense strength and high conductivity of carbon nanotubes could be exploited in composite materials if ways can be found to cheaply assemble the tubes into suitable macro-structures. Recently, US researchers have succeeded in making nanotube foam and others have made nanotube gels. In the UK, researchers at Cambridge have pulled a thread of carbon nanotubes more than 100 metres long. The challenge now is to spin the thread so that it retains enough of the strength and conductivity of the individual nanotubes. [M][N][S] It has been postulated that a layered material might show very low thermal conductivity if the interfaces are close enough together and the differences in the vibrational properties of the two materials are sufficiently large. Researchers at the University of Illinois have now demonstrated this effect using a structure of alternating nano-layers of tungsten and alumina. Such nanolaminates might be useful as high-performance thermal barriers in, for example, turbine-engine blade coatings. [M][A][N][P] |
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| [E] Environment, transport and marine | |
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The Commission for Integrated Transport estimates that the passenger capacity of a high-speed rail line is 50 per cent greater than that of a three-lane motorway, as well as offering journey times roughly a third of those for road in the UK. The capacity could be increased further by advanced signalling systems to manage high numbers of trains running close together. According to thinking at Imperial College, a high speed rail system in the UK could overcome the present transport crisis and reduce the population congestion in SouthEast England. [E][I][P][T][X] Planetary waves are gentle pressure oscillations in the atmosphere, set up by the rotation of the Earth. They usually roll gently around the planet, carrying weather systems with them. However, when an integral number of wavelengths fits into the Earth's circumference, the resonance enhances their amplitude and weather systems become pinned. Global warming is likely to make such resonances more frequent and this could explain why Europe experienced prolonged rain and massive flooding in 2002 followed by a prolonged drought in 2003 with the hottest summer in at least 500 years. [E] A 7-year experiment using loblolly pines growing in an enclosure containing carbon dioxide levels 50 percent about normal has found that the rate of growth was unchanged, except in dry years where tree growth was restricted by lack of water. The scientists believe that in normal or wet years growth is limited by the availability of nitrogen in the soil, and the tree is unable to make use of the higher levels of carbon dioxide. This result discourages hope that trees can offset global warming by absorbing the extra CO2 by growing faster. [E] The Sahel, south of the Sahara desert, is experiencing a prolonged drought that is probably a result of global climate change. Dust from the Sahel is blowing across the Atlantic on the trade winds and, in the summer, the air in Florida and the Caribbean can now contain so much dust that it exceeds health standards for particulates and is dangerous for people with respiratory or heart disease. [E][H] A new study shows that the deep-ocean circulation system of the North Atlantic is integrally coupled to salinity levels in the Caribbean Sea. Currently these are low by historical norms and this increases the danger that melting of the glacial ice of Greenland could profoundly change the salinity in the North Atlantic that drives the Gulf Stream. Though it is thought unlikely that this could trigger another ice age, it could lead to much colder weather in Northern Europe and Britain and perhaps in eastern Canada and the Northeast US. [E][X] A survey by the American Association for the Advancement of Science has found that most US adults believe that human activity is endangering the Earth's oceans, yet less than one-third feel empowered to influence positive change. More than 1,100 marine scientists have signed a statement calling on the UN and world governments to stop the destruction of deep-sea corals. [E] According to a new report, global warming is harming coral reefs in at least three ways. Changes of just 1 or 2 degrees C can stifle the algae on which the coral polyp feeds. Rising levels of carbon dioxide in sea water make it more acid preventing the polyps oozing their limestone skeleton. Thirdly, warmer water makes the reef more vulnerable to other threats, such as overfishing, diseases and pollutants that drain into coastal waters. Around 15 percent of coral reefs are now damaged beyond repair and a further 30 percent are likely to be lost in the next three decades. The Great Barrier Reef is predicted to lose 95 percent of its living coral by 2050. [E] Placing satellite communication devices on the backs of migrating turtles and the fins of dolphins has shown that they use particular off-shore highways. Preventing fishing inside these highways is important for saving endangered species. More than 200,000 loggerhead and 50,000 leatherback turtles are estimated to have been caught by accident in 2000, and both species could be extinct by 2050. Longline fishermen hunting tuna or swordfish regularly hook turtles by accident, and loggerhead and leatherback turtles have only a 50 percent chance of avoiding being accidentally snared each year. Unfortunately the highways are not precisely fixed in location, but since turtles generally swim in the top 40 metres, fishing inside the highways is safe below this depth. [E][R] Climate change is affecting the abundance, size and composition of plankton in the North Atlantic and this may be just as important as over-fishing in causing the current collapse in fish stocks. [E] Shark populations are falling catastrophically. The oceanic whitetip sharks, once the most common sharks in the world, are now almost extinct, according to a new census in the Gulf of Mexico that shows that their numbers have fallen by more than 99 percent over the past 50 years. [E] |
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| [R] Remote sensing and sensor systems | |
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A new technique for undersea sonar mine detection can make the seabed 'transparent' according to US researchers funded by NRL. Their technique uses time reversal to illuminate objects of interest. However, unlike earlier time reversal methods, it selects only part of the data from the initial echo to retransmit as the time reversed signal. This enables the seabed signal to be is suppressed, while the signal from buried objects is enhanced. [R][D] To help protect salmon populations, an airborne lidar system has been used to track adult salmon returning to spawn. Because the salmon swim within a few metres of the surface, they can be seen by the lidar, which uses a Q-switched Nd:YAG laser. [R][O] Engineers in UCLA have patented a radar device that can see through snow in order to help snowploughs steer clear of rocks and curbs. It exploits negative refractive index materials so that it can produce an image good enough to show what the object are and yet use a radar frequency of around 1 GHz that is sufficiently low to penetrate well through the snow. The imager could also potentially be used to help dig victims out from avalanches. [R][O][S] Europe's two largest airport operators will trial a new radar system designed to detect runway debris next month. British Airports Authority (BAA) and Aeroports de Paris (ADP) expect to run operational trials of QinetiQ's Tarsier radar system at Southampton and Paris Charles de Gaulle airports respectively. [R][A] Scientists at the NCAR are testing a new system that uses two radars at different wavelengths to pinpoint water droplets in clouds that could cause icing on aircraft wings. [R][A] The active phased array tactical radar ground surveillance system (TRGS) is the world's first radar system capable of providing simultaneous 360 degree ground surveillance, according to its developers EADS. [R] Sandia engineers have created a radar tag sensor that is mounted on military vehicles. The device, tracked via aircraft radar, can be used to identify both US and coalition forces during combat to avoid fratricide. [R][A][D][I] A tiny synthetic aperture radar (SAR) developed at Sandia is expected to achieve a range of about 15 kilometres, adequate for small UAV applications. The mini-SAR weighs less than 30 pounds and is one tenth the volume of the SARs on current UAVs such as Predator. [R][A][S][U] Georgia Tech is developing a landmine-detection system that uses high frequency seismic waves to displace soil and objects by less than ten-thousands of an inch. A non-contacting radar sensor then measures the displacement and this reveals any buried mines, including plastic mines, which are hard to detect by other means. [R] |
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| [S] Sensor devices | |
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Engineers at Caltech have succeeded in cramming the entire functions of a radar system onto a single silicon chip. This could make radar sensors cost effective to use in cars as obstacle sensors and parking aids. The chip, which radiates at 24 GHz, could also be used for communications. [S][I][J][R] A single test using a DNA sensor chip can now reveal the presence of meat from any of 32 different species in food samples. This enables inspectors to check whether food is really what it claims it is, so long as food producers have not treated the meat to destroy the DNA. [S][G] A US company has developed a sensor the size of a grain of rice that can be implanted in the heart of patients suffering from congestive heart failure and can be rf-powered to provide measurement of the blood pressure within the heart. [S][H] Dartmouth researchers have developed an algorithm that uses mass spectrometer data to distinguish the blood of healthy people from those with certain diseases. They claim that in trials the algorithm successfully detected ovarian cancer with virtually 100 percent accuracy and prostate cancer with approximately 95 percent accuracy. They also say that the algorithm provides clues about the molecular identities of abnormal proteins and peptides associated with the diseases. [S][C][H] TeraHz imagers have many potential applications including guidance, security, biomedical imaging and quality control. However, TeraHz radiation is hard to generate and to detect. Researchers at the University of California and at Imperial College London have developed a class of metamaterials that respond magnetically to teraHertz radiation. The material consists of a two-dimensional array of repeat-patterned copper elements, called split ring resonators, deposited on a quartz plate. [S][M][O][R] Fibre ring-down sensors work by measuring the decay time of a laser pulse travelling around a long loop of optical fibre. They have been used to measure trace quantities of gases and liquids. US researchers have now used the ring-down concept in fibre pressure and temperature sensors for use in extreme environments where conventional sensors based on fibre Bragg gratings and fibre Fabry-Perot interference are not suitable. [S][O][R] |
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| [O] Optoelectronics, optics and lasers | |
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Intel has created the first high-speed optical modulator made from silicon. Its bandwidth is greater than 1 GHz and it operates at the 1.5 micron wavelength of standard optical communications. Silicon could now start to replace compound semiconductors for high speed optical switches, and cheap silicon chips combining optical and electronic functions could soon be possible. [O][C][I][J] Philips has developed a fluid filled lens that can be focused using an electric current. It consists of a short cylinder filled with two liquids - an electrically conducting aqueous solution and a non-conducting oil. The fluids are immiscible, forming two distinct layers, and also refract light differently. The cylinder is coated with a material that repels the aqueous solution but not the oil, causing the interface of the two liquids to form a curve towards the centre of the lens. Applying an electric current makes the coating less water repellent (electrowetting) and causes the curve to flatten, changing the focal length. The curvature can even reverse from convex to concave. [O][R][S][V] Two groups have provided more evidence for flat-panel lensing and better-than-wavelength focusing of microwaves using left-handed (negative refractive index) materials. Research at the University of Toronto has shown that a source of microwaves can be lensed better than the diffraction-limit would allow and that the energy losses in the material are minimal. Researchers in Russia have achieved a spatial resolution as good as one-tenth of the wavelength. [O][R][S] A Hungarian architect has combined concrete with optical fibre to create building blocks that transmit light. Thousands of optical glass fibres form a matrix and run parallel to each other between the two main surfaces of every block. It is claimed that the building blocks retain the strength of normal concrete. [O][M] A US company has developed a holographic storage material photosensitive to blue light between 400 and 410 nm wavelength for storing data at very high resolution. The company believes that a 130 mm diameter disc will store up to 1.6Tb of data by 2010, and the cost can be just $50 for a 200Gb disc. [O][C][M] US and French scientists have developed a new technique that can provide high resolution millisecond-by-millisecond images of the membrane potential of nerve-cell signals deep in intact tissue. It combines multiphoton laser microscopy with specially developed dyes, and detects the nerve polarity by the second-harmonic radiation that it generates. [O][B] Physicists at Vienna University of Technology using pulses of UV laser light to watch electrons moving around atoms, have distinguished events only 100 attoseconds apart. They believe that the technique could soon be refined to track events a few tens of attoseconds apart, telling physicists how electrons rearrange themselves inside an atom when they move between different orbits. They hope the research can improve understanding of the role of electrons in superconductivity and in giant magnetoresistance. [O][F][M][S] Researchers at Max Planck have successfully demonstrated cavity cooling. A probe laser is used to excite a cavity containing atoms to be cooled. Photons then escape from the cavity with slightly increased energy thereby cooling the atoms. Unlike existing laser cooling techniques, cavity cooling preserves the quantum state of the atoms, and it can be used to cool molecules and other systems, which cannot be laser-cooled by conventional methods because of their more complex energy level structure. Being able to cool molecules to almost Absolute Zero would open a huge range of new research, for example on the fundamental forces and properties of the electron. Also, because the internal quantum state of the atom or molecule does not change, cavity cooling could make it possible to process quantum information stored in atoms. [O][C][F] A new technique called two-photon lithography can produce complex structures with sub-micron features. It uses dyes that are hundreds of times more efficient at absorbing two photons than previous photoactive materials. Since the rate of two-photon absorption depends very strongly on light intensity, a focused laser beam photoactivates the dye in a very small region, providing very high resolution. [O][J][M][N] |
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| [I] IT, communications, networking and secure systems | |
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In 2003, a Spectrum Policy Task Force organised by the US FCC found that much of the electromagnetic spectrum already licensed is not really in short supply. In much of the radio spectrum, even for premium frequencies below 3 GHz in dense urban areas, most bands are quiet most of the time. New radio transmission and networking technologies can squeeze vastly more capacity out of the same spectrum. [I][C][K][R][T] The new standard, IEEE 802.3ak-2004, provides an economical way for Ethernet switches and server clusters located within 15 metres of each other in equipment rooms and data centres to be interconnected at 10 Gb/sec. [I] Carrying a RFID tag that has been programmed to flood the reader with responses instead of beaming back one unique code, could prevent RFID readers intruding on privacy and might make the use of RFID tags in shops more acceptable to the public. [I] A two-yearly UK government survey has found that 93 percent of UK businesses, and 99 percent of large businesses, now use anti-virus software, and almost 60 percent update their protection automatically to protect against new threats. Despite this, half of firms, and 68 percent of large companies, were damaged by viruses during 2003, particularly by the Blaster worm. [I] Current Intel-compatible processors cannot distinguish between sections of memory that contain data and those that contain program instructions. Hackers exploit this in order to insert malicious program instructions in sections of memory that are supposed to contain data only, and then use buffer overflow to overwrite the "pointer" data that tells the processor which instruction to execute next. Buffer overflows are the largest class of software vulnerabilities that lead to security flaws. To overcome this, AMD's new Athlon-64 processor (for PCs) and Opteron (for servers) will protect against buffer overflows when used with a new version of Windows XP. Intel plans similar features on next generation Pentium chips. [I][C] NEC claims to have broken the quantum cryptography distance record by 50 km, successfully sending a single photon over a 150 km optical fibre link. US company Magiq and Swiss firm ID Quantique are already selling quantum cryptography hardware with shorter ranges over optical fibre. [I][O] |
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| [K] Knowledge, information and technology management | |
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Coalition forces in Iraq are now able to communicate more effectively among themselves and with the Iraqi people thanks to 'coalition chat line' software that uses 'instant messaging' techniques. [K][D][I] Section 404 of the Sarbanes-Oxley act, hastily passed by Congress in 2002 to force companies into better corporate governance, requires meticulous documentation of accounting and other processes. This amounts to terabytes of electronic data and is creating a huge opportunity for radical change in data storage and networks. [K][C][T] For certain classes of data that may be very expensive or difficult to obtain, a new statistical technique may provide useful information from a single data run by allowing meaningful re-sampling. The technique, known as "wavelet bootstrapping" or "wavestrapping," combines the techniques of bootstrapping and wavelet analysis. It has wide uses in geophysical sciences, turbulence, bioinformatics, medical imaging and nanotechnology, and is also useful for rapidly obtaining information from small data sets in such applications as medical diagnostics. [K][C][H][R][S] The World Wide Web Consortium (W3C) has approved the Web Ontology Language (OWL). OWL is a key standard for creating the semantic web, along with the existing standards, XML and RDF. Together they will enable the internet to become a global infrastructure for sharing both documents and data, allowing information to be searched by its meaning and not just by its word content, as at present. [K][C][H][I][V][W] Turning the massive quantities of gene data into an understanding of how particular groups of genes work together to control specific biological processes involves vast problems of data and information fusion. A computational tool produced at Stanford University can help in this by using a probabilistic framework that integrates data from a variety of sources including microarrays, DNA sequences, and protein-protein and protein-DNA interactions. The tool generates hypotheses in the form ''Gene A regulates Gene B under Condition C" that can then be tested experimentally. The method has successfully found gene regulatory networks in a variety of biological processes in yeast. [K][C][G][X] The US government has announced a new regulatory approach that is designed to allow open communication among researchers whilst preventing bioterrorists gaining access to cutting-edge research results that they could turn into weapons. [K][D][G] In April 2003, the UK's Medical Research Council established a task force to assess which models for conducting research work best. The models include government-funded facilities, research universities, virtual organisations, pan-national institutions, private labs, high tech start-ups, and company in-house laboratories. The task force found that no model is uniquely best. However, increasingly the models are mixing, linking and converging, particularly to harness the value of the research by stronger coupling. [K] As the cost and difficulty of creating new drugs have continued to rise, the prevailing modes of doing business in pharmaceuticals are no longer sustainable. To survive, companies are engineering more streamlined processes and seeking economies of scale from large centralised research organisations, but are also trying to establish a more agile small-company culture through niche oriented business units coupled more strongly to market pull. The new approach emphasises having better drug candidates rather than more, using new tools for discovery and development such as high-throughput screening and combinatorial chemistry, and having greater access to innovative work done in the biotech sector through partnerships and acquisitions. Greater emphasis on drug delivery early in the discovery process can be vital to success for drugs that are difficult to deliver, such as poorly water-soluble compounds. [K][C][G][H][T] |
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| [C] Computing, supercomputing, modelling and simulation | |
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The AMD Opteron 64-bit processor is based on an Intel-compatible 32-bit chip with 64-bit extensions. It can support more than four gigabytes of memory and 64-bit software, whilst also running existing 32-bit software in the usual way. It is proving more successful than Intel's clean sheet approach which designed an entirely new 64-bit chip, called Itanium. Itanium systems are powerful but expensive, and cannot run existing 32-bit software efficiently without its being extensively rejigged. [C][T] Computer simulations suggest that light signals could be stored in a chip using rows of tiny semiconductor pillars that could slow light waves to a stop and store them as electromagnetic fields oscillating within the pillars. A future computer might process the quantum states of such light pulses, rather than the states of electrons. [C][J][N][O] Scientists at the University of Michigan have observed entanglement between an individual cadmium atom and a photon. This has potential for creating a quantum supercomputer. The next step is to run two experiments side by side and mix up the two photons that fly away from the atoms in the hope that this will remotely entangle the two cadmium atoms. [C][O] A US gaming company is building a detailed Earth simulation for the US Army to help it prepare for conflicts around the world. The simulation uses a real-world terrain database. The emphasis in the artificial Earth is on human interaction rather than conflicts involving lots of military hardware. [C][B][D][V][X] The UK Foresight project on flood defences has produce a computer game that allows planners to test out ideas in a 3D virtual world against various complex scenarios. The game uses sophisticated geographical information. It has an extensive hydrological model built into a 3D landscape, which takes into account real information about rainfall, drainage, tides, climate and topography. [C][V][X] Virtual museums using 3D computer modelling could bring historical monuments to life. Engineers at the University of Geneva had developed virtual reality models of two Turkish mosques dating from the Ottoman era of the 16th century. Users can move around and explore the buildings in real-time. [C][V] |
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| [W] Whole life engineering, manufacture and testing | |
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Because of its high cost, traditional knowledge-based engineering has been limited to the car giants and to large aerospace organisations such as Boeing, BAE Systems and NASA. Now more affordable modules are coming along. These can help to automate processes for producing new product variants, use information to guide designers, check the implications of design changes, and capture and link every detail of the design and its possible variants to 'top level' or functional inputs. [W][A][T] A portable X-ray device designed to detect stresses in large components such as turbine blades and aircraft wings has been developed by researchers at Oxford University. The device uses intense x-rays and is capable of analysing large critical components for signs of residual stress without causing damage to the part itself. [W][A][S] The growth and rate of obsolescence of personal computers, handsets, PDAs and other IT products are creating a 'tsunami of toxic trash' and also consuming a lot of resources in their manufacture. Longer product lives, better upgradeability, improved recycling, safe disposal, financing arrangements and government incentives are needed quickly and worldwide, according to a new UN report into the environmental consequences of the information technology revolution. Manufacturing one desktop computer and 17-inch CRT monitor uses at least 240 kg of fossil fuels, 22 kg of chemicals and 1500 kg of water, which is far more materials intensive than an automobile or refrigerator. [W][E][I][M][T] Direct laser forming, using a single-component metal powder as the build material, provides another way for rapid prototyping of metal parts. Layers of powder are injected and micro-welded by a diode pumped solid-state laser. Once complete, each layer has a thickness of 30-100 microns and a density of almost 100 per cent. The results are similar to the products created by conventional casting. Applications include dental prostheses and other medical implants, and quick repair of military equipment in theatre. [W][D][M][O] The Joint Strike Fighter may be the first combat jet ever assembled on a continuous moving assembly line. The F-35 JSF team believe such an approach could increase production efficiency, reduce floor space and save an estimated $300 million in expenses over the life of the programme. [W][D][A] |
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| [X] Systems, complexity and risk | |
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Most people's e-mail comes from a limited social network, and these networks tend to be clustered into clumps where everyone knows each other. This makes them different from e-mails radiating from a spam source. Researchers at UCLA have devised a simple system that maps the clusters from a user's inbox and outbox and uses this to identify spam. The technique is able to reject about half of the spam without ever wrongly rejecting real mail. [X][I] Research at University of Michigan and the Santa Fe Institute has demonstrated a new way to reveal the structure of large, complex networks. The method finds highly linked "clumps" within the network by searching out and eliminating the links between the clumps. This differs from conventional methods of finding clumps, which is to search for the high density linkages within the clumps. Another method developed at Cornell is to use Web crawlers to map the communications links around the Internet. They have used this to study how influence propagates, what sort of connectivity makes people most influential, and how networks grow and develop over time. [X][B][C][D][E][G][I][K] The speed with which a network can synchronise depends on the topology of the network connectivity. The brain grow synaptic connections in a highly specific but irregular fashion. A simple model suggests that in random networks, the speed of synchronisation only slowly increases with the average number of connections per node. This implies that brain areas that need rapid information exchange must be highly connected. [X][B][C][I] A new system developed at Oregon State uses basic information about the ecology of "vector" borne diseases to mathematically predict how they might change, spread and pose new risks to human health. [X][D][H] According to research at the University of Illinois, complex systems that at high resolution are computationally irreducible and therefore unpredictable can often be described simply and predictably at lower resolution. Finding under what circumstances large-scale rules emerge that allow a simple, predictable description of a complex phenomenon could make some highly complex systems amenable to simple methods of analysis. [X][C] |
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| [V] Virtuality and human-machine interface | |
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A start-up company in Liverpool, UK, has developed a cheap device that generates a 3D computer representation of any object it scans. The company believes that the device can be cheap enough to sell to consumers, such as gaming fans who would like to take representations of their real possessions into the virtual world. [V][C][S] A UK net provider is testing a system to let people send aromatic e-mails over the internet. It uses a cartridge containing 20 basic aromas, which can be combined to produce up to 60 different smells under control from the PC. [V][I] Mitsubishi has developed a reversible LCD that displays the image on both sides for use in folding cell phones. [V][I][O] Troops wearing biological and chemical protection suits, or other forms of protective clothing, can very quickly succumb to heat exhaustion if they are working in a warm environment. And, in a hot climate, troop performance can be severely restricted even wearing ordinary clothing. Researchers funded by the US Army are developing a lightweight cooling vest that promises to be only a tenth of the weight of existing cooling vests. It uses ammonia and is powered by hydrocarbon fuel. [V][H][M] Research on how deaf children develop sign language indicates that humans are born with an inate ability to develop a form of communication that becomes an actual language. Some features, including the use of order to convey who does what to whom, are strongly inate. However, other characteristics are difficult to generate without linguistic input. For example, youngsters inventing their own sign language do not form verb tenses. All the structures identified in the deaf children's gesture systems can be found in natural language systems that have evolved over generations. [V][B][K] |
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| [B] Brain research and human science | |
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Understanding the neurochemical pathways that regulate social relationships may help to deal with defects in people's abilities to form and sustain relationships. Such defects can be disabling, as evidenced in autism and schizophrenia, and in the serious depression that can result from rejection in love. Pair-bonding between prairie voles has been well studied, and depends on two hormones, oxytocin and vasopressin, involved in the parts of the brain that help to identify individuals and thereby create sexual imprinting. The role of oxytocin and vasopresin in the human brain is less well understood, but may be similar. By using MRI scans to look at the brains of people who are passionately in love, researchers are unravelling some surprising features, finding that such love is similar to the euphoria induced by drugs such as cocaine and dissimilar to experiencing strong emotions. [B][T] Drug abuse produces long-term changes in the reward circuitry of the brain. Knowledge of the cellular and molecular details of these adaptations could lead to new treatments for the compulsive behaviours that underlie addiction. [B][H][T] Studies of 12,000 children born in Oakland, California, between 1959 and 1966 indicate that exposure to lead while in the womb may double a child's risk of developing schizophrenia later in life. [B][E] Studies have shown that giving choline, a member of the vitamin B family, to pregnant rats improves learning and memory in their offspring. The pups also suffer less from failing memories as they get old. Research now shows that this is due to having bigger brain cells in vital areas. If these results translate to humans they could make people smarter for their whole lives and forestall age-related memory decline, according to the researchers. [B][H] Scientists have previously established that people remember emotionally charged events and facts better than neutral ones. Now researchers at MIT have discovered that memories with an element of arousal or excitement are remembered by a different area of the brain - the amygdala - from memories of a calmer nature, which are remembered by the prefrontal cortex. [B][K] Theories about the effects of caffeine in the workplace are conflicting. Some studies suggest caffeine can worsen anxiety and trigger stress, while others show it boosts confidence, alertness and sociability, making certain tasks easier. A new report released by the UK's Economic and Social Research Council backs the view that coffee exacerbates stress, especially in men, and makes people less co-operative when working in teams. [B][K] Rats exposed for a day or longer to weak magnetic fields oscillating at 60 Hz developed damage to the DNA in their brain cells, according to research at the University of Washington. The field levels were similar to those from household devices such as blow dryers, electric blankets and razors. Several laboratories in Europe and India have reported similar effects. The US scientists also found that the cumulative damage from brief exposures appears to build up over time. [B][G][P][V] Researchers have produced the strongest evidence yet that placebos cause observable changes in how the brain responds to pain. They found that volunteers subjected to harmless but occasionally painful electric shocks or heat, experienced less pain when they believed that an anti-pain cream had been applied to their arm, and that fMRI scans showed the pain circuits in their brains were also less active. [B][H] Using fMRI, researchers at UCL have found that the ability to appreciate other people's pain empathetically involves the identical parts of the brain that register direct pain. Although no one actually "feels" the physical pain of others, the brain appears to be able to run a virtual simulation that represents part of the other person's experience. [B][H] Most stokes are caused by a clot blocking the blood supply to part of the brain. A US study has shown that treating severe ischaemic stokes with thrombolytic drugs rapidly, preferably within 60 minutes of the stroke onset, can greatly benefit most patients. Rapid treatment now appears to be as important for a stroke as it is for a heart attack. However, one difficulty is that patients must also have computerised tomography (CT) scans of the brain taken before treatment begins in order to confirm that the stroke is caused by a clot and not a haemorrhage. [B][H] |
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| [H] Healthcare and medicine | |
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A Finnish study of 22,430 government employees suggests that corporate downsizing doubles the risk of death from cardiovascular disease in the remaining workforce and also increases health-related absences. [H][B][K][X] Destroying tumours by heating them with focused ultrasound looks increasingly promising as an alternative to surgery or radiotherapy. French surgeons used ultrasound to treat around 240 elderly prostate cancer patients for whom surgical removal of the prostate was considered too risky. Over the following five years around 65 percent of the patients remained free of cancer, a similar success rate to surgery. But rates of incontinence, the major side effect of surgery, were cut from 80 percent to 8 percent. Ultrasound can tackle cancer anywhere in the body, as long as tumours are not obstructed by bone or pockets of gas such as air in the lungs. [H][P][S] A new technology called electroperturbation, which uses electric pulses tens of nanoseconds long to alter the intracellular structure of a cell, may lead to improved methods for treating diseases such as cancer and leukaemia. The pulses are so brief and intense that they pass virtually undetected through the outer membrane of the cell without damaging it. Inside the cell, however, the pulse perturbs the internal structures and can prompt cell suicide. [H][G][P] Tests of an anti-cancer vaccine have achieved encouraging results on patients with late-stage lung cancer. The vaccine included cells from their tumour and a gene called CM-CSF, which changed the surface of the cells to help the immune system identify them as cancerous. [H][G] Tests in mice suggest that sunscreens that incorporate fragments of DNA can greatly reduce the risks of skin cancer. The DNA fragments mimic the damage to DNA caused by sunburn and trigger production of proteins that repair and protect cells' genetic material from further mutations that might lead to cancer. [H][G] Numerous past attempts to make synthetic blood have failed because the blood has caused vasoconstriction. Now a US company may have solved the problem, according to the results of trials on animals and on 20 human patients in Sweden. Synthetic blood could reduce the need for blood donations and the problem of disease transfer through blood transfusion. Tests in hamsters that had lost a lot of blood showed they actually fared better when given the synthetic blood than when given real blood. [H][D] A small study published in 2003 hinted that infection with a virus GBV-C protects HIV patients from developing AIDS. This has now been confirmed by a much larger study. Survival 6 years after original HIV infection was 75 percent for those who were continuously infected by GBV-C but only 39 percent for those with no evidence of GBV-C infection, and only 16 percent for those who "lost" their GBV-C infection sometime in the first six years. This is the first proven case of one virus thwarting another in human medicine, and also provides a possible new approach for treating AIDS. One possibility is that GBV-C enables individuals to mount a stronger immune response to HIV. Another possibility is that GBV-C could somehow interfere with HIV entry into cells. Thirdly, GBV-C might also activate certain types of innate immunity, which involve known cellular factors that protect cells. [H][G] The World Health Organization has issued a warning about the prevalence of tuberculosis (TB) 'super-strains' that are resistant to the two major drugs for treating TB, isoniazid and rifampicin. The worst-affected areas are in eastern Europe and central Asia. As many as 14 percent of new cases in these regions involve multidrug-resistant (MDR) strains of the bacterium. [H][D] |
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| [G] Genomics, biotechnology and bioinformatics | |
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Genetic risk factors to health can be age-related. A genetic factor that is associated with lower cholesterol levels and protects people against heart disease in middle age turns out to be disadvantageous for extreme longevity, probably because it causes serum cholesterol to fall critically low in older age. [G][H] Studies of longevity in yeast and worms have pinpointed a gene known as Sir2 as a key regulator of lifespan: deleting Sir2 limits lifespan, and extra copies lengthen it. Now research indicates that, in mammals, Sir2 regulates a group of proteins known as FOXO transcription factors. FOXO proteins are linked with longevity; they control the expression of genes that regulate cell suicide, and also enable the cell to resist oxidative stresses that can disrupt the cell's DNA. This suggests that longevity may result, at least in part, from biochemical interactions that boost cells' ability to resist environmental stresses while inhibiting them from committing suicide. [G][H] Experiments in rats show that gene therapy can make muscles respond much better to exercise. The gene triggered increased production of a growth hormone called IGF-I. This, together with intensive exercise, caused the rats' muscles to become 15 to 30 percent stronger than would be expected with exercise alone. The therapy is targeted at treating diseases such as muscular dystrophy. However it could be used to produce genetically enhanced athletes and could be difficult to detect. [G][B] US scientists have found that traditional varieties of major American food crops are widely contaminated by DNA sequences from GM crops. The tests could not discover whether any crops were contaminated with sequences from pharm or industrial GM crops because there are no current tests for these. However, the concern is that if food crops were to become contaminated with genes that produce drugs, vaccines, plastics and harmful chemicals this could be a serious threat to human health. [G][H][X] Scientists have identified a key protein which seems to control the passage of cholesterol into the bloodstream. Some existing anti-cholesterol drugs may work by blocking this protein, and new and better drugs may now be possible. [G][H] New research on mice suggests that ovaries in humans and other mammals may function quite differently than previously thought. Rather than containing a limited supply of immature eggs as currently supposed, they may instead generate fresh eggs from stem cells throughout reproductive years. [G][H] Researchers in Seoul have cloned 30 human embryos and harvested stem cells from them. In culture, the cells formed all three of the main tissue types that normally appear in the beginning stages of embryonic development. Grafted into mice, they were able to form muscle, bone, cartilage and connective tissues. Stem cells made using a patient's own DNA should be able to repair and replace damaged tissue without being rejected by the immune system. [G][H] Clinical trials at Seoul National University in South Korea have shown that when heart attack patients are injected with their own blood stem cells these help to repair the heart. Unfortunately most patients also developed abnormal growth around implanted stents. It is not yet clear how serious a complication this will prove to be, but another possibility may be to avoid the need for blood stem cells by stimulating stem cells in the heart itself to divide and repair the damaged tissue. [G][H] Researchers at Duke University Medical Centre are now confident that cells that they derived from fat and coaxed into converting into bone, cartilage, fat and nerve cells are indeed truly adult stem cells with multiple potential and not just a mixture of different types of cells, each with a more limited destiny. This is an important step forward for stem cell therapy that uses the patient's own cells to avoid any immune reaction. [G][H] Stem cells might provide a treatment for baldness. Researchers have found that stem cells plucked from the follicles of mice can grow new hair when implanted into another animal. [G] By introducing a gene called telomerase, which enables stem cells to live indefinitely, into more specialised "progenitor" cells, scientists have created an unlimited supply of a type of nerve cell found in the spinal cord. They have used the cells to partially repair damaged spinal cords in laboratory animals, re-growing small sections of the spinal cord that had been damaged. [G][B][H] Bacteria communicate by releasing chemicals enabling groups of bacteria to alter their collective behaviour. Now scientists at UCLA have genetically engineered bacteria to communicate with new chemicals. They hope eventually to be able to produce modified cells of pathogenic bacteria that can be introduced into a natural colony of the same cells, and then triggered to produce compounds that destroy the colony. [G] Rapid progress is being made in understanding the workings of the molecular motors in biological cells, based on dyneins, kinesins, and myosins. [G][N][T] Myosins are proteins that function as molecular motors and carry out cellular motion by attaching to and "walking" along fibres of actin. The interaction of actin and myosin is the mechanism behind cell actions such as muscle contractions, cell division, and transport of molecules inside cells. Research at Stanford shows that myosin molecules can also act as clamps and one of the 18 types of myosin, myosin VI, provides the rigidity and tension needed by the tiny sensors in the inner ear in order to respond to sound. The researchers believe that many intricacies of cellular organisation may exploit myosin motors that can create structural changes by taking up slack in proteins and clamping down so that they remain in a rigid position. [G][N] Two US teams have found new ways to string together artificial DNA bases. Non-natural forms of DNA can be more robust than natural DNA and do not break apart when exposed to high temperatures. Such super-DNA could be useful in a wide range of medical and technological applications. A team at Scripps used directed evolution to develop enzymes capable of stitching together the artificial bases. Another team at University of Florida used an enzyme made by HIV. This proved capable of making multiple copies of non-natural DNA, opening up the possibility that the code could eventually evolve on its own. [G][M] Biological cells can fuse together, merging their cytoplasms. In the case of cancer cells this fusion process can escalate, engulfing up to 1000 tumour cells and killing them. However the problem has been to control this fusion so that it does not engulf and kill healthy cells. Mayo Clinic has now developed a process which they call "biofusion" that achieves this by using a genetically engineered cell membrane. It causes dendritic cells in the body to fuse directly with tumour cells at multiple sites in the patient. The researchers believe that this marks the cancer cells for destruction by the immune system more effectively than existing approaches to cancer vaccines. [G][H] |
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| [N] Nanotechnology and molecular technology | |
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Researchers at Cornell have produced a nanoelectromechanical cantilever device that can weigh a mass as small as an attogram. They hope the device will be able to detect and identify tiny chemical and biological species, such as viruses. [N][G][S] DNA has great potential for creating nanoscale structures that are needed, for example, to organise devices in future nano-electronic circuits, or to hold viruses and proteins, or to build nanomachines. Researchers at the Scripps Institute have synthesised a single-stranded DNA molecule that will fold up into a hollow octahedral structure roughly 22 nm in diameter under certain conditions. The molecules can be readily copied by polymerases. An octahedral structure gives good rigidity and because all twelve edges of the octahedral structures have unique sequences, they are versatile molecular building blocks that could potentially be used to self-assemble complex higher-order structures. [N][G][M] Nanotubes are thought of as being rigid rods but researchers have now found that they can be bent easily by weak fluidic forces. They can curl round a liquid drop and remain bent when the drop has evaporated. Arrays of bent nanotubes should be able to detect fluid flow. The strain induced by bending may also change the tubes' optical and electronic properties in ways suitable for designing sensors and field emitters. [N][J][S] Researchers at Georgia Tech have grown nanorings of single-crystal zinc oxide. The material is piezoelectric and semiconducting, and hence the nanostructures could have applications in sensors, resonators and transducers. The method may be applicable to other semiconductors that, like zinc oxide, possess a wurtzite crystal structure. [N][M][J][S] Single carbon-60 molecules have been individually doped with potassium atoms using a scanning tunnelling microscope. This ability to control the doping of individual molecules is important for building molecular level electronic devices. The next stage is to extend the technique to more complex molecules and other dopant atoms. [N][J][M] |
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| [J] Microelectronics, MEMS and spintronics | |
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The viability of spintronics depends on finding ways to combine ferromagnetic metals and semiconductors in integrated circuits. This is challenging because of the differences in crystal structure and chemical bonding, and because conventional semiconductors must be fabricated at high temperatures, making it hard to produce the ultra-thin layers necessary to make a spin valve. Physicists in Utah have now built a spin-value using a thin layer of organic semiconductor sandwiched between two ferromagnetic electrodes. They successfully injected electrons with aligned spins into the organic semiconductor and showed that the spins stayed aligned as the electrons moved through the semiconductor. Applying a weak magnetic field produced a 40 percent change in the electrical current, which qualifies as giant magnetoresistance. The spin-up or spin-down alignment of electrons was also maintained when power was shut off – a property needed for non-volatile spintronic computer memory. [J][M][N] In the shoot-out over what lithography technology will be used for 60 nm feature sizes out to 2009, the winner looks like being 193 nm immersion lithography, yet again succeeding in stretching existing lithography approaches a bit further. Beyond 2010, as feature sizes reduce to 40 nm and below, the likely contenders are extreme ultra-violet (EUV) and 157 nm immersion lithography. [J][O][T] As chips get more and more complex, interconnection is coming to dominate chip area, performance and cost. Over the past 20 years, planar interconnection has managed to keep place with increasing chip complexity by adding up to nine layers of interconnect on top of the chip and using low-k dielectrics to insulate wires with reduced cross-talk. However, as adding more interconnect layers gets increasingly costly, many other possible interconnection technologies are waiting in the wings: optical and rf connection may be particularly useful to global and external interconnect, whereas 3-dimensional circuits, X-architecture and network-on-a-chip may provide dense local interconnection. There are also some blue sky possibilities, such as using nanotubes, spin-coupling, and molecular interconnects. [J][M][N][O][T] Researchers at John Hopkins University have built rubbery circuits out of several squashed but extendable gold wires. The wires are a few microns in thickness and are encapsulated in a springy polymer. They can be stretched by over half their initial length without loss of electrical conductivity. Applications envisaged include wearable electronics and artificial nerves that can bend inside the body. [J][B][H][N][S][V] |
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| [F] Fundamental science | |
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At the University of Vienna, physicists have observed the transition from quantum to classical behaviour in carbon-70 molecules. Below 1000 degrees Kelvin, the molecules demonstrate quantum behaviour when they pass through a double slit. However, at higher temperatures the emission of thermal photons caused the molecules to decohere. [F][N] The Higgs boson may have been discovered. A signal obtained at the Large Electron Positron Collider (LEP) in Geneva before it was dismantled to make way for its replacement, the Large Hadron Collider (LHC), could turn out to be the Higgs. If correct, the particle's mass is around 115 GeV, at the limit of the energy range that was achievable with the LEP. Finding and studying the Higgs boson is the primary reason for building the LHC. [F] The Hubble Space telescope has provided images of some of the farthest and youngest galaxies ever seen, including objects from a mere 500 million years after the Big Bang. Swiss and French astronomers using the Very Large Telescope in Chile have also pictured a small cluster of stars that are about 13.2 billion light-years from Earth, only 470 millions years after the Big Bang. Estimating the abundance and properties of sources at such early times is important in understanding "the Cosmic Renaissance" when the Universe reionised itself, ending the Dark Ages during which the Universe was opaque to light. [F][R] Biological cells on small particles of dust could be driven out of the solar system by radiation pressure quickly enough to remain biological viable. In this way the Earth could have seeded life widely among life-supporting planets in its local region of the Galaxy. Earth should spread its seed most widely when we pass through a giant molecular cloud, a mass of dusty material from which stars are born. This has happened about five times since life appeared on Earth. A similar process might also have seeded life on Earth originally. [F][A][G] Researchers at the University of Ohio have shown from string theory that at high densities of matter, such as those within a black hole, the effects attributable to strings can grow to large sizes. This suggests that the interior of a black hole can be thought of as a ball of strings. The strings act as a repository of the information carried by things that have fallen into the hole, so that, as quantum mechanics requires, no information is destroyed. As well as resolving a long standing paradox about what happened to the information, the theory also appears to remove the “singularity” that had been thought to lie at the centre of every black hole. It may also be able to explain why the universe is so uniform without needing to postulate the strange mechanism of cosmic inflation. [F] |
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| [T] Technology reviews | |
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The US Department of Energy has published a strategic plan for its research over the next 20 years. The plan sets seven short-term (5-10 year) scientific priorities: the ITER fusion science experiment, scientific discovery through advanced scientific computing, using nanoscale science for new materials and processes, microbial genomics, physics to explore the basic forces of creation, exploring new forms of nuclear matter, and developing the facilities for the future of science. [T][C][D][E][F][G][K][M][N][O][P] From being a niche technology in satellite links and deep-space communication, turbo codes are about to be introduced into mobile telephone systems. This will allow multimedia data such as video and graphics-rich imagery to flow over the noisy channels typical of cellular communication. A revolutionary concept when they were proposed by two French engineers in 1993, turbo codes get to within just 0.5db of the Shannon information theory limit. Prior to that, even the best codes usually required more than twice the transmitting power that Shannon's law said was necessary to reach a certain level of reliability. Turbo codes are also being studied for digital audio and video broadcasting, and for increasing data speeds in enhanced versions of Wi-Fi networks. [T][I][C][R] This is likely to be the year when hybrid vehicles start to take a significant slice of the automobile market. Also this year, hydrogen and fuel-cell technologies are getting increasing R&D priority by every major automaker. LEDs are being adopted for indicators and tail-lights, giving higher efficiency and longer life. Electronic sensor-based control is gaining attention: roll stability control (RSC) adjusts the braking to avoid the risk of rolling over, and active steering adapts the gearing and stiffness of the steering by using measurements of road speed, body roll, yaw, braking input, and wheel traction. Intelligent driver support is also being developed. This will, for example, automatically correct if the vehicle is steering out of its lane. [T][E][M][P] |
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