DON’T SELL YOUR house and flee to the hills just yet. If the notion of billions of miniature robots munching their way through our defenceless planet sounds like a great idea for a science fiction novel, then that’s because it is. There may be risks associated with nanotechnology, but fears it will trigger a grey goo armageddon are fanciful.
The grey goo idea was first floated by Eric Drexler in 1986. He raised the prospect that ‘nanobots’ (created to build structures atom by atom) could produce endless copies of themselves, gradually tearing the world apart and leaving it a quagmire of grey goo.
The closest science fact comes to battalions of self-replicating devices is the attempt to direct organic molecules to assemble themselves into useful structures, for drug-delivery systems, say.
Many scientists do have concerns: some nanoparticles could be poisonous. Their size makes them a potential health hazard for the lungs. Worrying for lab workers, but hardly the stuff of books and films.
Relatively easy, with a decent sample of skin, hair, saliva, blood or bone and another to compare it with. And it helps, of course, if you have a rough idea of who you’re trying to identify.
Humans are remarkably alike – one human differs from another by about 0.1% of their DNA – but this still adds up to about 3 million differences. In 1984, Alec (now Sir Alec) Jeffreys of Leicester University noticed that these tell-tale patterns in the human genetic code could serve as a kind of genetic fingerprint.
In 1985, this kind of DNA evidence solved a British immigration dispute by linking a child to a mother. In 1986, the world’s first DNA-based manhunt unmasked a killer, Colin Pitchfork, who murdered two 15-year-old girls in Leicestershire.
Some DNA carried in the mitochondria of the cells is inherited only from the mother: this mtDNA has proved a powerful tool for solving ancient mysteries. It means that living descendants from the same maternal line can provide mtDNA, which can then be matched with that recovered from a long-dead body.
We know that the outlaw Jesse James did indeed die from a single bullet wound in Missouri in 1882, because his sister’s maternal great great grandson donated mtDNA that matched samples taken from unearthed remains.
DNA donated by a mother and sister helped US military researchers identify the unknown soldier of Vietnam at Arlington Cemetery. He turned out to be Michael Blassie, a pilot shot down in 1972.
DNA from handkerchiefs, toothbrushes and razor blades was used to confirm the identity of at least some human remains from the Twin Towers tragedy of September 11, 2001.
There are, however, two challenges: DNA breaks down, becoming harder to recover with time; and the world is smeared with it. Human beings leave behind invisible showers of skin, hair and body fluids wherever they go. So contamination is always a potential hazard for forensic researchers.
You can never make something totally hacker-proof but, with a bit of quantum cryptography, you will always know if someone is trying to get at your messages.
Keeping private communications private relies on complex mathematical operations, which can all be cracked. You just need time. Try hacking a message encoded using quantum cryptography, though, and the laws of physics will instantly raise the alarm. Until now, messages encoded in this way were not strong enough to make much of a communication system. But scientists have succeeded in sending and receiving quantum-encrypted messages over 100 km – the furthest distance so far.
The technique is based on sending single particles of light, or photons, along an optical fibre. Each photon is encoded to represent a standard bit: 0 or 1. In a standard optical communication system, each bit is carried by a million photons. An eavesdropper could split off some photons – say a hundred or so – and determine the information they were carrying.
But because photons can’t be split, the quantum technique is more secure. ‘This stops a crude tapping-type attack where an eavesdropper tries to steal some of the photons,’ says Andrew Shields, leader of Toshiba’s quantum information group in Cambridge, which developed the system. ‘In quantum cryptography, each bit is carried by a single photon so if you remove that photon then it’s gone and the receiver never receives it.’
Quantum physics also tells us that you can’t copy a single photon faithfully. ‘If somebody tries to copy the signal they introduce changes, and those can be detected by the sender and the receiver,’ says Shields.
One problem with the technique has been that photons are easily scattered out of the fibre. This reduces the signal which can get so low that it gets lost in the background noise.
‘There’s nothing we can do to reduce the scattering – that’s fixed,’ Shields says. ‘We developed a very sensitive photon detector with very low noise counts and that meant we could tolerate a lower signal rate or have a longer fibre.’
The easiest way, of course, is simply to get hold of one of the phones used to send and receive the messages. But there are other ways, all of which need specialised equipment and a lot of preparation.
Text messages are sent over mobile phone networks in a similar way to voice conversations: the main difference is that the text is sent to a central processing centre, where it is stored until the recipient’s phone is in reception range. According to a spokesperson for Vodafone, the message is then stored for up to 21 days (mainly to authenticate the sender and subsequently bill them) and then it is deleted. So anyone wanting illicitly to grab a text message between other people would have to do it during transmission. And that means being close to one of the participants.
‘A common way of intercepting mobile calls is to fool the handset into thinking that your transmitter is its local base station,’ says Anthony Constantinides, a communications professor at Imperial College London. ‘The user then communicates through you, allowing you to listen in.’ Potential hackers would have to be in the same cell, the geographic area served by a single base station, as the target.
Recovering deleted text messages from the phones themselves is also possible. ‘It’s the same sort of principle as when you delete a computer file,’ says Fred Piper, director of the information security group at Royal Holloway, University of London. ‘It’s still there until it’s overwritten.’ But this would require direct access to the phone or sim card.
As Stephen Hawking once put it: ‘The physics that underlies Star Trek is surely worth investigating.’ Scientists say that in principle such a weapon might be possible, but that you’d never get it through the door. ‘You need extremely high voltages and so it would be something the size of a car,’ says Karl Krushelnick, head of the plasma physics group at Imperial College London.
In 1997 Eric Herr of the Californian company HSV Technologies patented a design using laser light. The lasers generate intense beams of ultraviolet light that create a path of ionised air between the weapon and the target, up to 100 m away. The air then conducts an electric current to cause muscle spasms or stun for a few seconds. Herr says he is developing a prototype device about the size of a suitcase.
Ask anyone in the industry and they will quickly correct you: it’s bullet-‘resistant’ glass. ‘There’s no such thing as “proof” in this business,’ says Phil Brown of Pilkington, the glass manufacturer. ‘Proof suggests it will definitely stop anything fired at it. We tend to shy away from claims like that.’
Bullet-resistant glass is simple to make. Thin layers of a clear, tough plastic called polyvinyl butyral (PVB) are sandwiched between sheets of standard glass, and bonded together by heat. Alternating layers of plastic and glass are then built up. The more layers, the better the bullet-stopping power.
Bullets don’t just bounce off it, of course. Fire a bullet at a pane of bullet-resistant glass and it will break the outer glass layer, and probably layers of glass deeper inside the pane. But the tough PVB sheets are designed to absorb its energy, preventing it from breaking through to the other side. At least, that is the idea.
Bullet-resistant glass is tested for strength using different calibres of guns. A shot from a modern rifle will need at least a 5 cm-thick pane to stop it, since the bullet speed is so high, typically around 820 m a second. Naturally, it takes less to stop a bullet from a handgun as the bullet travels much more slowly.
Some security companies offer ‘one-way bullet-resistant glass’, designed to stop incoming bullets, while giving the person on the inside the option to shoot back. The glass works by using a brittle glass layer and, again, a tough polymer layer. The brittle layer faces outward and shatters if a bullet is fired at it, spreading the force of the bullet over a large area, which is then absorbed by the tough layer behind. A bullet fired from the other side, however, can puncture the polymer layer easily before breaking the glass, only slowing the bullet slightly.
The term ‘controlled explosion’, which is widely used in the press, actually covers a range of different operations. But the army often, perhaps surprisingly, uses water to carry them out.
There is understandable reluctance among defence ministry employees, army engineers and the companies that make bomb-disposal equipment to talk about how exactly they do it, so perhaps we should point out that everything that follows is from information already in the public domain.
For an example, take an abandoned car near an airport. Under such suspicious circumstances, the army’s first task is to discover whether the car actually contains a bomb or not. Remote-controlled robots can be sent in carrying cameras and fitted with special tools and small explosive charges to open locked doors. In this case it’s possible that the three controlled explosions carried out simply involved blowing open the locked doors.
If something suspicious is seen, then the level of alert – and the technology used – is quickly raised.
X-rays can help to judge whether an explosive device is present, and perhaps how sophisticated it is. But what really matters is the attempt to disable or disarm a bomb without accidentally triggering an explosion. This is where the water comes in. Very, very high powered jets of water.
‘Water would be shot out of a cannon at very high velocity,’ says one expert who works for a company that produces remote-controlled robots used in bomb disposal. ‘It penetrates into the object, splatters everywhere and literally takes it apart. Hopefully the timing devices, the motion sensors and whatever may be in the set-up will not have time to make contact and ignite the explosion.’
Because the water used to shatter the bomb is cold, it is unlikely to ignite any explosive material. ‘Also, being water it tends to short circuit all the circuits and wires in a fraction of a second,’ he says.
In some cases the results can be astonishing. The British company PW Allen in Tewkesbury makes security equipment including the water ‘disruptors’ used in bomb disposal.
On its website it describes one piece of equipment called a ‘disposable car boot disruptor’, which can be placed on the ground beneath a vehicle believed to be carrying a large bomb. When activated, the device ejects water that physically tears the bomb apart with enough force ‘to blow two filled aluminium beer kegs from the closed boot of a car to a height of approximately 10 metres’, the site says.
In principle it’s very easy – get a critical mass of radioactive material, sit back and watch the runaway nuclear reaction go. But luckily for us it’s the first part – getting the radioactive material – that is the biggest stumbling block.
‘You cannot make a nuclear bomb without fissile material,’ says Andrew Furlong, of the Institute of Chemical Engineers. And for an average thermonuclear device, the necessary material is plutonium or enriched uranium.
Uranium, a naturally occurring heavy metal, comes as uranium 238 or 235. Both are radioactive and will decay into other elements, given time, but only the latter can be forcibly split when neutrons are fired at it. This is the basis of a nuclear bomb.
When an atom breaks apart, it gives out energy and more neutrons, which can then split other atoms. Get enough atoms splitting and you have the chain reaction needed for a bomb blast.
But natural uranium overwhelmingly consists of the 238 isotope, which bounces back any neutrons striking it – useless then for a bomb. To make a bomb, natural uranium needs to be treated to concentrate the 235 isotope within it.
And this is where the problems really begin. For every 25,000 tonnes of uranium ore, only 50 tonnes of metal are produced. Less than 1% of that is uranium 235. No standard extraction method will separate the two isotopes because they are chemically identical.
Instead, the uranium is reacted with fluorine, heated until it becomes a gas and then decanted through several thousand fine porous barriers. This partially separates the uranium into two types. One is heavily uranium 235, and called ‘enriched’, while the rest is the controversial ‘depleted’ uranium used to make conventional weapons.
To make a nuclear reactor, the uranium needs to be enriched so that 20% of it is uranium 235. For nuclear bombs, that figure needs to be nearer 80 or 90%. Get around 50 kg of this enriched uranium – the critical mass – and you have a bomb. Any less and the chain reaction would not cause an explosion.
You could use plutonium instead. According to Keith Barnham, a physicist at Imperial College London, this is the preferred material because it makes much lighter weapons that can be mounted on to missiles.
Plutonium is produced as a by-product in nuclear reactors and only around 10 kg is needed for a bomb. An average power plant needs about a year to produce enough and expensive reprocessing facilities are required to extract the plutonium from the fuel.
The bomb will explode once the critical mass of uranium or plutonium is brought together. So, to begin with, and to make sure that it doesn’t explode in the hands of its owners, the bomb needs to keep the metal separated into two or more parts. When the weapon is in place and ready to go off, these sub-critical masses need only be thrown together – and this can be done with conventional explosives.
The chain reaction, explosion and familiar mushroom cloud then take care of themselves.
Shockingly easily. If you thought that your phone conversations were secure, think again. Covertly listening in on phone calls is a doddle if you know how.
‘It’s almost as easy as plugging in something to an electrical outlet, that’s the scary part about it,’ says Grant Haber, president of American Innovations, manufacturers of covert and counter-surveillance equipment.
Telephones are very simple devices. A microphone converts your voice into electrical pulses, which are then relayed through a wire out of your home and through several telephone exchanges on the way to the person you are speaking to. At any point in this line, somebody can simply attach a device to the wires which will convert the electrical information back into sound.
At its simplest, this device can be another telephone. More sophisticated bugs convert the electrical current into radio waves and transmit the information to a receiver – usually a van parked somewhere near the transmitter.
Mobile phones are more difficult to intercept, but it’s still relatively easy to do. For around £250 you can buy equipment that allows you to tune in to any calls going on in your area.
‘A normal mobile telephone isn’t actually secure,’ says Anthony Constantinides, professor of communications and signal processing at Imperial College. ‘There is no encoding procedure that actually secures such conversations.’
The digital mobiles in use today are encrypted but the codes all conform to international standards so that phones can work overseas. ‘Anybody can undo the encoding,’ concludes Constantinides.
Another common way of intercepting mobile calls is to fool the handset into thinking that your transmitter is its local base station. The user then communicates through you, allowing you to listen in. The only drawback for a potential hacker is that they have to be in the same cell – the geographic area served by a single base station – as you listen in.
To get around this, satellites can be used to hone in on any particular spot. ‘Satellites can transmit information much in the same way as a base station,’ says Constantinides.
And there are easier ways for governments, for example, to listen in to phone conversations – such as asking the phone operator to patch them in.
If you like your answers based on proof, then this particular one has to be a firm ‘no’. But the issue has been raised by Victor Aziz, a psychiatrist at Whitchurch Hospital in Cardiff and expert in so-called musical hallucinations.
Just like the more familiar visual variants, musical hallucinations strike suddenly. ‘People will all of a sudden start hearing a song, such as “Yes, we have no bananas”,’ says Aziz.
Musical hallucinations are rare and usually linked to some kind of abnormal behaviour in the brain, be it a psychiatric condition, epilepsy or a tumour. But Aziz says people are more likely to experience them if they go from hearing a lot of music to a quiet place in which their brains receive little auditory stimulus.
Traditionally, scientists thought that hallucinations were more common among those who listened to a lot of music in childhood, but Aziz found that many of his patients were hearing more recent songs.
Aziz believes that in the iPod age, the increase in the amount of music we are exposed to will make hallucinations more common. ‘We are now exposed to a barrage of music and it seems that we might well see more cases of this in the future,’ he says. ‘We’ll only know if we test people in twenty years’ time,’ he added.
Ironically, iPods and Walkmans are used by many patients who experience intrusive musical hallucinations, says Peter Woodruff, a psychiatrist at Sheffield University. ‘What they find is that by playing real music, it competes with the hallucination and suppresses it,’ he says.
Some auditory hallucinations are normal. On falling asleep and waking up, it is fairly common to think you’ve heard your name called, or less specific noises, Woodruff says. ‘It’s when they happen outside these times that you want to see a doctor.’
Brain scans of people experiencing musical hallucinations show that neural activity is identical to the state of really hearing the music. ‘It’s not like having a tune going around in your head,’ said Adrian Rees, an expert in auditory neurology at Newcastle University. ‘This is something you can’t turn off or change to another record.’
If you are a text message addict and own a BlackBerry, the hand-held gadget with email, text, pager and mobile phone, then you may have experienced BlackBerry thumb. Reports say thousands of BlackBerry owners have been turning up at doctors’ surgeries complaining of aching thumbs from using the device’s tiny keyboard. Frantic texting on ordinary mobile phones may also leave people vulnerable to the condition. So is the condition likely to reach epidemic proportions?
‘At the moment no one knows, but a big uncontrolled experiment is happening right now because so many people send texts,’ says Roger Haslam, a professor of ergonomics at Loughborough University. ‘The number of young people who intensively use mobile phones is particularly alarming.’
Thumbs were never designed for texting, so it is not surprising that they complain when asked to tap out messages all day long. ‘The most obvious problem is tendon injuries,’ says Haslam. If thumbs are repeatedly bending then the tendons begin to rub as they are stretched over the knuckle joint. Eventually this leads to swelling and pain. ‘Tendon injuries can be difficult to get rid of and once you have had one then you are often susceptible to it happening again.’
Alternatively, BlackBerry thumb sufferers may be showing the early stages of osteoarthritis. ‘The thumb has more than two planes of movement, allowing it to flex and rotate. This means that some people develop pain at the base of their thumb associated with osteoarthritis,’ says Sean Hughes, professor of orthopaedic surgery at Imperial College London.
What can you do to avoid it? ‘Take lots of breaks and stretch the fingers regularly,’ Haslam says. In addition it may be worth tailoring your phone to your hand. ‘Find a phone that feels comfortable and listen to your body. If you start to get aches and pains then do something about it early on.’
Put simply, one piece of fast-moving metal looks pretty much like another to a radar operator, whether it’s the rotating blades of a wind turbine or the approach of an enemy aircraft. Which is why the Ministry of Defence takes such an interest in where green energy developers intend to erect them. ‘There are genuine concerns over how wind turbines can interfere with our radar systems,’ says the MoD.
The problems start with the fact that wind turbines are very large, made of metal and have sharp edges. Sound familiar? They would if you were sat at a radar listening for returned ‘pings’ bouncing off aircraft – in fact they might sound exactly like a jumbo jet. Hence civil airport authorities and air traffic controllers have a problem with wind farms, too.
The rotating turbine blades fool techniques used to filter out tall buildings, trees and other stationary objects. And because different blades can be picked out during different radar sweeps, banks of turbines appear as a confusing, twinkling mass on screens that can make genuine targets difficult to pick out. There are even concerns that turbines cast a radar shadow behind them, within which enemy planes would be invisible, though measurements indicate that it would last for only a few hundred metres and would hide only very small objects.
The government – which has promised to generate 10% of electricity from renewable sources by 2010 – and industry are investigating a number of solutions.
Software fixes that help radar systems filter out signals from wind farms have been developed, though these work better with offshore wind farms surrounded by lots of flat sea. Another option is to redesign the turbines and the way they are arranged so they better blend in with terrain.
The military research company Qinetiq is using stealth bomber technology to build turbine blades that don’t show up on radar screens. ‘We’re looking to change the properties of parts of the material structure to reduce the amount of reflection,’ says Andy Beck, a radar expert with Qinetiq. Making the turbine blades from different layers the right thickness can bounce back signals that neatly cancel out the arriving pings. And honeycomb-style foam can absorb enough of the incoming radar energy to send very little back.
The simple answer is lots of soap, water, mopping, vacuuming and elbow grease. But for a chemical, biological, radiological or nuclear contamination, some extra technology may be required. According to the government’s new booklet that advises on how to prepare for an emergency, we may have to wait for the emergency services to decontaminate buildings before we can go home. So what might the emergency services be doing and will we want to go back home afterwards?
One technique, used on chemical and biological contaminants, is to pump reactive gases and vapours into the building, to react with the contaminants and mop them up. Reactive gases and vapours (such as chlorine dioxide or hydrogen peroxide) permeate into porous materials, like soft furnishings, carpets and wallpaper, react with the contaminants and then diffuse out again. For more targeted and precise cleaning operations, peelable coatings can be applied to a contaminated surface. These sticky strips are coated in a polymer that binds with the contaminant and are useful for awkward areas.
Although these methods will make your house sparkling clean, they can also leave a rather unpleasant smell. In Florida, the National Enquirer’s AMI building (contaminated with a letter containing anthrax in September 2001) was decontaminated using a strong disinfectant called para-formaldehyde. The building is still vacant as a result. ‘The problem with formaldehyde is that it smells so badly, no one wants to use the building afterwards and it’s so corrosive, it’ll strip the paint off your walls,’ says Ray Zilinskas from the Centre for Non-Proliferation Studies in Monterrey, California.
For radiological and nuclear contamination, high-pressure hosing, steam-cleaning and extensive vacuuming may be the way forward. Of course, all the debris from this intensive cleaning has to be collected and disposed of in a site for hazardous waste. Organic solvents with low boiling points (such as acetone) also come in handy. They can be heated until they vaporise and then circulated throughout the house. The vapours permeate porous materials, where they condense and dissolve the contaminant, before diffusing.
These techniques are all costly: around $800 million has been spent on decontaminating the 23 buildings in the USA that were contaminated with anthrax. Unless your house is very special, it may just be demolished. ‘The cost of decontamination can become very expensive. It may very well be cheaper to raze the building and start all over again,’ says Jerry Loeb, also from the Centre for Non-Proliferation Studies.
Bigger than the new Airbus A380, that’s for sure. And the world’s largest passenger jet is some way from breaking any records.
Its 79.8 m wingspan is no coincidence. Aircraft wanting to use boarding gates and taxiways at the world’s airports need to operate inside an 80 m box.
The biggest aircraft in the sky is the Russian Antonov 225 cargo plane, a full 10 m longer than the Airbus, with a wingspan more than 88 m. Bigger still, Howard Hughes lifted off in his Spruce Goose flying boat, which had wings an incredible 98 m across. Debate still rages about whether his brief, low-level test flight in 1947 really counts.
As a plane gets bigger and carries more passengers, it weighs more. Heavier planes need more lift and so bigger wings. Kenji Takeda, an engineer with the aerodynamics and flight mechanics research group at the University of Southampton, says conventional wings can only grow so far before they are unable to safely support their own weight.
‘With the A380 I know they had some problems in terms of how big a bit of aluminium they could get,’ Takeda adds. Some of the pieces have to be made from the same original ingot for structural reasons.
He says the new Airbus is probably at the peak of the trade-off between size and efficiency. Future designs could see a return to biplanes or a new ‘flying wing’ concept to generate yet more lift.
The European manufacturer has stressed the plane’s green credentials as the first long-haul aircraft to consume less than three litres of fuel per passenger over 100 km – comparable to an economical family car.
Aircraft manufacturers claim that winglets, as they are known, cut drag and boost fuel efficiency by up to 5%. Though they have been reported as a new trend, they have been around longer than you may realise.
NASA first realised their aerodynamic benefits in the 1970s and, as the price of aviation fuel has soared in recent years, winglets have become the latest must-have in the skies. Boeing says requests for winglets on its 737s are up from 10% in 2001 to 50% this year.
Philip Butterworth-Hayes, editor of Jane’s Aircraft Component Manufacturers, says: ‘I reckon you’re only looking at 1–2% increase [in fuel efficiency] using a winglet but that is really quite significant. I reckon they will soon be on every airplane.’
British Airways has winglets on 57 jumbo jets and 66 shorter-haul Airbuses, which were in place when the planes arrived from the manufacturers. Rival operators have invested in kits that equip their older aircraft with the ski-shaped ends. The fins can reach up to 4 m above the wing and work by evening out the air flow around the tips.
‘It’s well-known that modifying the wingtip flow is important,’ says Kenji Takeda, an engineer with the aerodynamics and flight mechanics research group at the University of Southampton. Soaring birds such as eagles have strong feathers that flip up at the wingtips to reduce drag and give the birds more lift. ‘Nature, as always, has sussed it out first,’ Takeda adds.
Winglets could bring other environmental benefits besides saving fuel. The altered air flow around the wingtips also reduces the formation of contrails, wispy streaks of cloud left behind when water vapour condenses around particles of pollution in engine exhaust fumes.
How contrails could influence global climate is still debated, though some scientists say they promote the formation of long-lasting cirrus clouds, which help to trap heat at the Earth’s surface. Last year, NASA scientists said an increase in cirrus cloud cover over the US of 1% a decade since 1975 was down to air traffic.
Trying to find big prime numbers is a useful way of testing computers, and very big prime numbers can be used to help encrypt electronic information. But there’s also the geek factor: big prime numbers are the sort of thing amateur mathematicians become obsessed by.
Prime numbers, numbers that are only divisible by themselves and 1, are a mathematical oddity. They appear seemingly at random along the number line.
Finding small ones (1, 3, 5, 7 etc.) is obviously easy – just divide each candidate number by all the smaller numbers and see if any of them go in a whole number of times.
As the numbers get bigger, however, this becomes unfeasible and you need some serious computing power. Prime numbers are widely used to produce encryption codes on the internet – when you submit your credit-card details to a website, for example, it will be encoded using methods that use prime numbers.
‘The security of those systems are based on the fact that it is very hard to factorise integers into primes,’ says Alexei Skorobogatov, a mathematician at Imperial College London. But to make that work effectively, you need big prime numbers.
For professional mathematicians, the allure of primes lies in the fact that they are seen as the building blocks of numbers.
‘Every whole number is a product of prime numbers,’ says David Solomon, a mathematician at King’s College London. ‘That is like the signature of the number.’
Primes, and number systems based on them, are used extensively in theoretical mathematics as tools to solve complex equations; when Andrew Wiles, a professor of mathematics at Princeton University, solved Fermat’s last theorem a decade ago, he worked with new mathematical techniques that use number systems based on prime numbers.
But academics themselves tend to shy away from the search for ever bigger numbers.
‘Mathematicians don’t, generally speaking, go around looking for prime numbers. The main reason is that we know there’s infinitely many prime numbers, so you’re never going to get to the end of the list,’ Solomon says. Instead, he says, they concentrate on more general questions such as trying to work out if there are indeed any patterns in how the numbers appear.
Because blood is made of many complex parts that serve specific functions: it’s tough to reproduce each one properly.
But Eishun Tsuchida, a biochemist at Waseda University in Tokyo, says he’s solved the problem. Using yeast to artificially manufacture human blood proteins, he claims to have produced the world’s first entirely synthetic red blood cells.
Hospitals always want as much blood as possible but there are risks that donations could be infected with CJD, hepatitis viruses or even HIV. ‘For a long time people have been trying to make replacements,’ says Sarah Middleton, chief executive of Haemostatix, a company that makes components for artificial blood.
So far, biotechnologists have looked at just one part of the puzzle. ‘When you need blood you need it for a particular purpose. You either need it to make a blood clot or you need it because you need more oxygen or fluid,’ says Middleton.
Each bit of the blood has its own problems. ‘The difficulty in making the red cell component is that you can’t really make cells that easily,’ says Middleton. People have tried to make the oxygen-carrying part of blood, a molecule called haemoglobin, which is the main component of red cells.
These are made up from proteins called globins and haeme, a small molecule that actually carries the oxygen. ‘The reason that haemoglobin is in a red cell is because there are certain moderating influences within the red cell that make sure that that happens correctly,’ says Middleton. ‘The other thing is that haemoglobin is small: if you just have a single globin with haeme on it and you were to inject that into somebody, it was would [go straight] through the kidneys and have no half life of circulation.’
Producing globins on a large scale is also difficult. At the moment, they are made by inserting a gene into yeast and allowing the organism to make them slowly but surely. But it would be difficult to make globins on an industrial scale this way.
And where do you get the haeme from? The US firm Biopure has successfully made artificial blood from a polymer of artificial haemoglobin molecules and its makers claim it is more efficient than real blood because it absorbs and releases oxygen three times faster. It is also less viscous than real blood, so can flow past obstructions that could block normal red blood cells. But its haeme is extracted from cows’ blood, and is unlikely to become popular in places such as Britain, where the fear of mad cow disease is still fresh.
Who better to enlighten us than three of Britain’s own Nobel laureates, Tim Hunt, Harry Kroto and John Walker?
‘As with all human affairs, it pays to be incredibly clever, incredibly hard working and incredibly lucky. But to be frank I’d put the emphasis on the last one,’ says Tim Hunt of Cancer Research UK, who with Paul Nurse won the Nobel prize for physiology or medicine in 2001.
Sadly, Lady Luck, and the fact that she might well forget to look your way, is something any wannabe Nobel prizewinner has just got to accept. But setting luck aside, there are ways of stacking the odds of landing a Nobel in your favour. One way is to take a chance on finding something no one else is even close to discovering.
‘These Nobel people are really keen on discovery with a capital D and with pioneers, people who really opened a door on something when nobody even realised it was there,’ says Hunt.
If taking the chance leads you to something interesting, it could give you a far better chance of winning a Nobel than jumping on the latest bandwagon. ‘You can be a brilliant scientist, be fantastically effective and have a huge team of people churning out results and never get within a million miles of winning a Nobel prize because you are treading a well-worn path. Everything you find out is more or less expected,’ says Hunt.
The best bet, according to Hunt, is to find just the right kind of experiment. ‘It’s no good trying to understand consciousness, you’ll just flail away getting nowhere, and it’s no good wanting to know how your left foot goes in front of your right because anybody can do that. But somewhere in between is that land where you might make a really big difference and discover something really important. That’s where you want to focus your effort,’ he says.
There is a risk in pursuing obscure scientific problems that no one else is interested in though. You could end up in an academic wasteland so bereft of interest that you fail to win grants and slowly find yourself unemployable. The key, whether by intention or accident, is to do the right experiment at the right time, says Harry Kroto of the University of Sussex, who won the Nobel prize for chemistry in 1996. ‘The most important experiments are the ones where you really don’t know beforehand where you are going or what you are going to find,’ he says.
At the very minimum, you need to be doing science because you feel a need to crack whatever problem it is you are studying. ‘If it’s hard work and you enjoy it, that’s a good start,’ says Kroto. ‘The only recipe I have for my research is that if it is interesting to me I do it.’
John Walker, director of the Medical Research Council’s Dunn human nutrition unit in Cambridge, and winner of the Nobel prize for chemistry in 1997, says that one of the worst mistakes you can make is to want a Nobel prize too much. ‘I’ve met several people who set themselves the task of winning a Nobel prize and most of them ended up very disappointed,’ he says. ‘I think it’s dangerous to assume you can win a Nobel prize because many people do good enough work, but for whatever reason they don’t actually win the prize. At the end of the day, it’s in the hands of the Nobel academies in Sweden and it all comes down to what they perceive as worthy of it.’
No. Any cosmologist would have a hard time ‘proving’ the existence of anything that exists before time or beyond space. An evolutionary biologist is in no position to demonstrate precisely how life began, simply what paths it took after it did begin.
Many scientists do believe in a personal God, but not because they have scientific evidence for Him. Some state that they are in no position to say whether God does or doesn’t exist. Isaac Newton and John Ray embarked on a study of the cosmos and of life on Earth, because they believed it would reveal God’s handiwork. Gradually, even the most devout began to accept that science showed no such thing.
‘I flatly reject the argument that the origin of life was some sort of miracle,’ says Paul Davies, author of a book about cosmology called God and the New Physics. ‘To be sure, we don’t yet know how it happened, but that doesn’t mean a cosmic magician is needed to prod atoms around.’
It is about burying cow horns full of manure and planting crops according to signs of the zodiac. Reports say the Prince of Wales has decided to experiment with some of the principles of biodynamics, a type of agriculture founded by an Austrian philosopher, Rudolf Steiner, in the early 20th century.
‘Steiner said you should treat the farm as an entity and know that whatever you do on one part of the farm affects it elsewhere,’ says Alan Brockman, a Kent-based farmer with 40 years’ experience of biodynamics.
Brockman says biodynamics means taking account of natural cycles when farming. ‘Say we want to plant carrots. We’ll pick out a constellation, such as Virgo, Capricorn or Taurus and plant them when the moon is moving through them. Those constellations all stimulate root development,’ he says.
But Geoff Squire at the Scottish Crop Research Institute says that, while seed germination depends on differences in temperature, sunlight and moisture, there’s no evidence that the moon makes any difference. As one scientist puts it: ‘Biodynamics? It’s kind of an occult-based farming system.’
Apparently not. For many years, mobile users have diligently switched off their phones after being told that sensitive electronic equipment on jets or in hospitals might malfunction under the influence of the microwave radiation emitted by the phone.
But it seems it may all have been unnecessary. ‘They were erring on the side of caution more than anything else,’ says John Pollard, a lecturer in indoor personal networks at University College London, about attitudes to mobile use on jets and in hospitals.
Indeed, research carried out by the Medical Devices Agency in 1997 showed that outside a metre or so of sensitive medical apparatus, there seemed to be no danger at all. ‘I can imagine that aircraft devices are much less susceptible,’ Pollard says.
A mobile phone base station in a plane would work by communicating directly with satellites if the plane is over water, or with normal base stations if they are flying over land.
Airbus wants to introduce the technology on short-haul flights in the first instance, to avoid the possibility of passengers who might be asleep on long-haul being disturbed.
As for hospitals, ‘what I’m told is that doctors ignore the ban anyway,’ says Pollard. ‘They’ve all got mobile phones and they use them willy nilly.
You bet. Digital simulations, electronic fuses, smokeless compressed-air propellant and even rockets carrying computer chips have all fizzed over the horizon in recent years, although the chances are that your local November 5 display will rely on more conventional methods.
‘The biggest difference is in the machines used to fire the displays,’ says John Bush of the British company Millennium Fireworks. Large displays are planned using computer simulations, which allow the bangs and whistles to be tightly coordinated with music and lights, if required.
And forget the well-wrapped-up men shuffling around with lit tapers – the firing of the fireworks in big displays is done digitally too, often using signals sent from a computer.
When it comes to the fireworks themselves, not much has changed in years. They still work on the idea that different metals give off different wavelengths of light when they burn to produce colours, and most use the same delay fuses to place the bangs in the right place. ‘There’s not a lot of difference, although colours have changed slightly and there’s a slightly wider palette than there was 20 years ago,’ says Tom Smith, who ran the London millennium firework display.
Fancier fireworks are available, but at a price. To reduce the smoky haze left by its nightly displays, Disney has experimented with launch tubes fired by compressed air, and some manufacturers even offer computer chips inside the explosive shells, which they say allow such accurate timing of explosions that words can be spelled out. ‘It’s possible but it’s incredibly time consuming and unbelievably expensive,’ says the Reverend Ronald Lancaster, a renowned firework expert.
And the million-dollar question, is there a difference between an ‘ooh’ and an ‘ah’? Bush says there is. Pretty displays such as fountains of sparks falling from bridges tend to draw the latter, while punters save the former for sheer extravagance. ‘That’s an ooh because you’re just firing so much money in such a short space of time,’ he says.
No one in particular. When a donor’s face is spread over a recipient’s skull and facial muscles, the effect is a hybrid that doesn’t look like either person.
Unlike in the 1997 film Face/Off, in which Nicolas Cage and John Travolta have their faces switched, the recipient doesn’t end up looking exactly like the donor.
‘It’s a big question, because donors’ families don’t want to walk down the street and see the face of their loved one,’ says Peter Butler, a surgeon who is investigating the issues surrounding face transplants at the Royal Free Hospital in London.
‘What happens is you get the skin tone and texture and the hair colour transferred, but the bone structure dictates most of what the face will look like. The end result is they look like someone different,’ he adds.
Anyone who has a face transplant in the future will need to have counselling beforehand to prepare themselves for how they will look afterwards.
‘One of the problems is that there is now a lot of high expectation around about face transplants,’ says Butler. ‘It’s important to remember these people will have severe facial injuries and the transplant will be an improvement. But it is unlikely they will look completely normal. There will be scarring and tissue damage that will affect the final outcome,’ he says.
The high failure rates reported for cloning animals is an indicator. According to Wolf Reik, of the Babraham Institute, Cambridge, around 99% of clones die in the womb or suffer genetic abnormalities.
But what goes wrong? The problem is that the DNA used to make the clone is taken from cells that aren’t meant to create embryos. When a cell matures and turns into a particular cell type, such as skin, it programmes its own DNA to express the right genes at the right time to become, and remain, a skin cell. This is done in two ways. Firstly, chemical compounds are tagged on to the central protein thread (chromatin) that DNA is wrapped around. Second, compounds called methyl groups latch on to specific genes, governing when and if each gene is switched on or off. The way the DNA is programmed is different for every tissue type.
It’s no surprise then that skin cell DNA can lead to appalling defects if used to grow an embryo. ‘You get the wrong pattern of gene activity during development, so the clone dies early in the womb or has developmental abnormalities when it is born,’ says Reik.
But the very fact that some cloned animals are born, at least superficially, quite healthy, suggests that every now and again, the DNA is able to ‘forget’ what kind of cell it used to be and apply itself to making an embryo. Scientists know that it is chemicals in the body of the hollowed-out egg that help reprogramme the DNA, but quite how remains a mystery.
Harry Griffin, deputy director of the Roslin Institute, which gave us Dolly the sheep, says claims that genetic abnormalities produced by the cloning process can be detected before birth are nonsense. ‘There’s no way you could pick up some of these subtle, but life-threatening defects,’ he says.
There may be another barrier to human cloning. Some studies have suggested that clones born successfully have a biological age the same as the animal that donated the DNA. ‘It could mean you age far more quickly,’ says Reik.
Lord Winston, fertility expert at Hammersmith Hospital in London, thinks so. He singled out claims surrounding research into embryonic stem cells as being particularly overblown. The danger, he said, was that hype could lead to public expectation becoming unrealistically high, setting up an inevitably painful fall when scientists fail to come up with breakthroughs in the near future.
Richard Ashcroft, a bioethicist at Imperial College London, says the stem cell hype might not be as bad as Winston makes out. ‘To build public support for what they’re doing, scientists are always going to say there is the prospect to cure all these horrible diseases, but they’re cautious for the most part in saying when those cures will arrive.’
But stem cell researchers, especially those working on embryonic stem cells, which must be harvested from early-stage human embryos, may be more prone to hyping their work than others, adds Ashcroft. Because embryonic stem cells are deeply frowned on by many religious groups and others who disagree with the use of human embryos in research, scientists are under greater pressure to extol the potential of their work.