Sommaire pour April 2016 de BBC Science Focus Magazine

In the not too distant future, the skies will hum with the sound of drones. It seems almost inevitable that we’ll see flying robots whizzing around overhead working as couriers, traffic wardens, police officers and more. Right now, though, their work is a little bit more glamorous. Scientists are piloting unmanned aerial vehicles (UAVs) into some of the most inhospitable corners of the planet and beyond. Whether they’re mapping the heart of a volcano or uncovering ancient Amazonian villages, these agile craft are launching a new age of discovery in which treasures are being found by fearless robots, rather than intrepid explorers. Check out the plucky drones on p34. Meanwhile, astronomers also have a new tool to help them explore the heavens. In February, physicists announced that they had finally…

Media scare Jamie Carter’s article ‘VR gets real’ (February, p68) points out many advantages of the use of virtual reality, but doesn’t mention the downside that should cause concern for many parents of schoolkids or students. Battlestar Galactica spin-off Caprica featured teenagers visiting hedonistic virtual reality nightclubs. It is, I find, quite sobering to think that children and students could enter nightclubs and try for themselves the ‘enjoyment’ of drinking and drug-taking before physically doing it. Yes, some people would argue that it’s not actually real. But from pretend games come the opportunities for youngsters to ‘learn’ the dark side of VR and meet with undesirables. I know technology is here to stay, but how do we avoid an issue such as this? Peter Carey, Portchester It’s unlikely that VR…

“ONLY THE SPINACH SHOWED POOR BIOMASS PRODUCTION” In hit sci-fi movie The Martian, stranded astronaut Mark Watney (played by Matt Damon) feeds himself by growing potatoes in soil from the Red Planet’s surface. Now, researchers from the Netherlands have replicated the feat using simulated Martian soil made from rock taken from Hawaiian volcanoes. The team successfully harvested 10 different crops including tomatoes, peas, rocket and cress. The plants grew just as well as controls planted in regular potting compost. “That was a real surprise to us,” said researcher Wieger Wamelink. “It shows that the Mars soil simulant has great potential when properly prepared and watered. Only the spinach showed poor biomass production.” The plants were grown in trays filled with a mix of simulation soil, which was created by NASA,…

It is still unclear why some people develop coeliac disease, but it appears to be associated with certain genetic mutations. The unpleasant symptoms illustrated here will clear up once a sufferer adopts a gluten-free diet. SKIN Brittle nails Acne Eczema INTESTINES Diarrhoea Bloating Constipation MOUTH Ulcers Enamel erosion JOINTS AND MUSCLES Pain Swelling STOMACH Pain Nausea IN FEMALES Infertility Miscarriage Early menopause The wall of the small intestine is covered with little, finger-like projections called villi. These give the intestine a large surface area, allowing the efficient absorption of nutrients. The image on the left shows how the villi become flattened and inflamed in sufferers of coeliac disease, while the image on the right illustrates the villi in a healthy individual.…

On 14 September 2015, a new window into the Universe was opened. Researchers at LIGO (Laser Interferometer Gravitational-Wave Observatory) caught the distant murmurs of two black holes colliding, and in doing so made the first direct detection of gravitational waves. This discovery is yet another victory for Einstein’s General Relativity. But more than that, because gravitational waves carry information about some of the most exotic events in the cosmos, they will allow astronomers to see the Universe in a new way. At the beginning of this revolution, here are some of the game-changing developments astronomers may uncover in the years ahead. Black holes The signal picked up by LIGO is believed to have come from two huge black holes colliding 1.3 billion light-years away. One of the black holes in…

“WORLD-CLASS RUGBY PLAYERS AND BOXERS OFTEN END UP CATEGORISED AS WADDLING FATTIES” First thing every morning I go through the same ritual. I stand on the bathroom scales to check if my weight is below 11st 7lb. If it’s not, my day is pretty much ruined. But if it is, I feel happy for, oh, as long as 30 seconds. The reason: 11st 7lb is the weight above which someone of my height becomes an official, certified lard-arse. Health experts put it slightly more politely: it’s the weight that, when expressed in kilograms and divided by the square of my height in metres, gives a Body Mass Index (BMI) in excess of 25 – which classifies as overweight. And that, in turn, means I’d face a greater risk of ill…

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1. Western Scotland Actual rainfall: 2,254.1mm Difference from 1961-1990 average: 135% 2. Northern Scotland Actual rainfall: 1,980.5mm Difference from 1961-1990 average: 123% 3. Northwest England and North Wales Actual rainfall: 1,576mm Difference from 1961-1990 average: 123% 4. Eastern Scotland Actual rainfall: 1,367.7mm Difference from 1961-1990 average: 123% 5. Southwest England and South Wales Actual rainfall: 1,304.5mm Difference from 1961-1990 average: 108% 6. North England Actual rainfall: 1,118.8mm Difference from 1961-1990 average: 119% 7. Northeast and East England Actual rainfall: 841.4mm Difference from 1961-1990 average: 112% 8. Midlands Actual rainfall: 798.1mm Difference from 1961-1990 average: 103% 9. South England Actual rainfall: 758.2mm Difference from 1961-1990 average: 99% 10. Southeast England Actual rainfall: 756.6mm Difference from 1961-1990 average: 99% Source:The Met Office metoffice.gov.uk/climate/uk/summaries/2015/annual/regional-values…

CRIME SCENE INVESTIGATION ‘Forensics officers’ are a crime show staple, but how does the work they really do match up to what we see on our TV screens? What is forensic science? Any scientific process used as part of a criminal investigation is considered forensic science. This spans both the grim, grisly procedures of the autopsy room and the cutting-edge analysis of a crime scene. But it also encompasses the less glamorous, painstaking lab work of DNA profiling, fingerprint analysis and the uncovering of hidden digital files. There is even such a thing as forensic accountancy. What techniques are used to solve crimes today? The bulk of modern forensic work involves the analysis of DNA or fingerprints left at a crime scene. In murder cases, forensic autopsies help work out…

MICHAEL MOSLEY The BBC science presenter looks at the lucrative free-from movement to find out whether gluten and lactose are really as evil as we are led to believe, or if we can tuck in to a guilt-free macaroni cheese. p46 ZOE CORMIER We’ve all typed in a Google search only to be greeted by some risqué images. But do we need to worry about the effect of porn on our minds? Science writer Zoe Cormier probes into the psychology to take a look. p68 TIM RUFFLE Tim Ruffle from Aardman Animations – the studio behind Wallace and Gromit and Shaun the Sheep – has turned his hand to something a little different this month by designing a flag for planet Earth. p76…

Question time In your March issue you ask “could your driverless car choose to kill you?” Is that moral dilemma really the point? Shouldn’t we be asking whether we should build something that can intentionally kill the user? Who would want to use such a device? And how should one weigh up the different factors? Is the person the car is choosing to save – at the cost of your life – a father of two young children, or a stroke patient, or 98 years old? Or let’s assume the passenger of the car and the bike are both of the same sex, age and marital status with children of the exact same age. The only difference is that one is a blue-collar worker and the other the prime minister.…

“How much of a landmark is this result? These results from Wageningen University are certainly exciting. Being able to grow our own food will be a critical component of long-term habitation on Mars – we’ll have to become space farmers! But we’re only just working out now what crop species might be best suited, and how to exploit ‘in situ resources’ using Martian water, nutrients and regolith [dust, soil and broken rock] rather than having to fly soil from Earth all the way to Mars. How closely did the experiment mimic the real conditions on Mars? This particular experiment used a simulant for the Martian regolith, but then added lots of organic fertiliser in the form of grass clippings and manure, which of course wouldn’t be available on Mars. So…

“AS WE DISCOVER MORE ABOUT BRAIN STIMULATION PROTOCOLS, WE’LL LIKELY SEE THESE TECHNOLOGIES BECOME ROUTINE IN TRAINING ENVIRONMENTS” Take the red pill: a team at HRL Laboratories in California has discovered that electrical brain stimulation can speed up the acquisition of skills. In the classic sci-fi movie The Matrix , Neo (played by Keanu Reeves) is able to learn kung fu instantly thanks to a device that uploads the martial art directly to his brain. While the HRL technique can’t quite replicate this, it was able to reduce the time trainee pilots took to learn to fly. The team measured the brain activity patterns of six commercial and military pilots, and then transmitted these patterns into novice trainees as they learned to pilot an aeroplane in a flight simulator. To…

PLUTO MAY HAVE CLOUDS Photos sent back from the New Horizons spacecraft following its flyby of Pluto last July show what appear to be hazy, cloud-like features in the atmosphere. Pluto was demoted to dwarf planet status in 2006. If confirmed, the finding could strengthen the case for it to be reinstated as a full planet. ‘SIMPLE’ FACES ARE CONSIDERED MORE ATTRACTIVE A study at the University of Queensland has found symmetrical faces with no unusual features are perceived as more attractive. The effect is thought to be due to ‘simpler’ faces being easier for the brain to process. GETTING TATTOOS CAN PROTECT YOU AGAINST COLDS Maybe it’s time to get inked. The body’s stress response triggered by having multiple tattoos can lead to a strengthened immune system, researchers at…

“THE ALGORITHM ENABLES CENTIMETREACCURATE GPS TO BE INCORPORATED INTO SELF-DRIVING CARS” GPS is ubiquitous these days. From geotagging our photos on Facebook to finding our way around using Google Maps, the ability to pinpoint our precise location has never been more desirable. There are more safety-critical applications for it too, like making sure self-driving cars, when they finally get here, won’t drive us straight off a cliff. There are potential wider uses too – future leagues of robots will need GPS to navigate the world. So a new, more accurate GPS system that can measure your location to within mere centimtres accuracy is a welcome arrival. Or is it? GPS, developed by the US military, works by triangulating your position on Earth’s surface relative to three or more satellites. The…

You probably don’t think that Wi-Fi uses a lot of power, but sending and receiving data does require electricity – mostly to generate the analogue radio frequency (RF) element of a Wi-Fi signal. And as more and more ‘always on’ devices and cloud services play a role in our daily lives, the total power consumption of Wi-Fi systems is growing rapidly. Enter ‘passive Wi-Fi’, a system developed at the University of Washington that’s capable of making Wi-Fi transmissions that use 10,000 times less power. Rather than relying on a network of devices each with its own RF transmitter, passive Wi-Fi uses a single RF element that’s plugged into the mains to take care of all radio transmissions, which make up the biggest drain of power. Digital signals, which require almost…

ENEMAS For those not familiar with an enema, it involves injecting a fluid into the lower bowel via the rectum. The main medical reason for carrying out an enema is to relieve constipation. Alternative practitioners, however, claim a wide range of other, unproven benefits. DETOXING/ FASTING If you’d asked me a few years ago, I would have been sceptical about detoxing. But I’ve since looked into the research surrounding intermittent fasting and changed my mind. Restricting calories for two days a week can improve health. VAMPIRE FACELIFTS This consists of taking some of your blood, removing the red cells, then injecting the resulting platelet-rich plasma (prp) back into your face. It sounds flaky, but is based on good science and can accelerate healing. URINE DRINKING I have seen people drink…

Gravitational waves are ripples in the fabric of space-time. Think of space a stretched sheet of nylon. If you placed a bowling ball into the centre, the fabric would warp and sink, creating a kind of funnel. Drop any more balls onto the the sheet, and they’ll roll towards the centre where the bowling ball is. The Sun makes a similar depression in space itself, giving rise to the gravity that pulls Earth towards it. As an object accelerates through space – say a planet orbiting a star – its motion causes distortions in this fabric, which ripple outwards as waves. The bigger the mass of an object, the bigger the waves. The recently spotted gravitational waves came from two colliding black holes – some of the hugest objects in…

DR CHRISTIAN JARRETT Christian edits The British Psychological Society’s Research Digest blog. His latest book is Great Myths Of The Brain. DR ALASTAIR GUNN Alastair is a radio astronomer at the Jodrell Bank Centre for Astrophysics at the University of Manchester. PROF ROBERT MATTHEWS After studying physics at Oxford, Robert became a science writer. He’s visiting professor in science at Aston University. DR PETER J BENTLEY Peter is a computer scientist and author who is based at University College London. LUIS VILLAZON Luis has a BSc in computing and an MSc in zoology from Oxford. His works include How Cows Reach The Ground. What happens to the donor’s DNA in a blood transfusion? SUSAN BOWNASS, YELLING There is virtually none there to begin with. Only the white blood cells have…

Credit is usually given to the Scottish-born scientist and engineer Alexander Graham Bell, who was granted a US patent for what he called an ‘acoustic telegraph’ in 1875. His claim comes complete with the famous story of Bell using his invention to call his colleague in the next room with the words: “Mr Watson, come here – I want to see you.” Yet like many major inventions, whether Bell deserves all the credit has long been the subject of debate, not least over what exactly constitutes a ‘true’ telephone. For example, some historians point out that Italian engineer Antonio Meucci and German inventor Philipp Reis independently invented telephone-like devices that achieved the key breakthrough of turning sound into electric signals over a decade before Bell. In 2002, the US House…

DNA phenotyping something of a holy grail for forensic scientists, DNA phenotyping would be the creation of a ‘photofit’ image based on a DNA sample alone. But our current knowledge of, and ability to analyse, DNA is not yet sufficiently advanced to make this a reality. DNA profiling A person’s DNA profile is not simply their entire DNA sequence, which is billions of letters long. instead, profiling compares the DNA in around a dozen highly variable stretches of the human genome. Entomology the study of insects. Forensic entomologists can work out the time of a victim’s death by studying the types of insects feeding on their corpse. Loops, whorls and arches these are the classic patterns made by the ridges of skin in a fingerprint. Fingerprints are still commonly used…

1 IT’S NOTHING LIKE TV Forensic science, especially DNA analysis, can often involve tedious laboratory work – something that TV programmes usually neglect to show. For forensic evidence to hold up under scrutiny in court, every stage of the process – collection, handling, storage, and analysis – must be conducted to impeccable scientific standards. 2 PRINTS AND PROFILES DNA and fingerprints are the most commonly used forensic evidence in criminal investigations. Apart from identical twins, no two people have the same DNA, and DNA samples are compared at points where the human genome is known to be incredibly varied. Fingerprints are still used, though, as they’re cheaper to process and more likely to indicate what someone has been doing. 3 EXTRAORDINARY EVIDENCE A huge range of materials can be collected…

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What did they do? A team at the University of roehampton trained eight king penguins to walk on a treadmill and filmed them as they waddled along. And what did they do that for? King penguins have to schlep several miles inland from the Antarctic coast in order to breed. As they have no means of hunting for food on land, they must first fill their bellies with fish to enable them to survive the breeding season. the researchers wanted to find out if the penguins’ walking gait changed with body mass. What did they find? tubby penguins tend to widen their gait to accommodate extra weight but they also sway more from side to side. this increased waddling gives them extra stability and helps prevent them from toppling over.…

Do you think you’ve got what it takes to be a science journalist? Well now’s your chance to prove it: the University of the West of England’s Science Communication Unit is launching a writing contest in association with the Royal Institution and BBC Focus . The competition is open to anyone who doesn’t write for a living, and entries from bloggers and scientists are welcome. The topic is ‘The next big thing in science’. To enter, write an article on that theme that’s suitable for publication in BBC Focus . The judges, who include the Royal Institution’s Gail Cardew, IFL Science’s Justine Alford and BBC Focus’s acting editor Daniel Bennett, will be looking for lively, well-researched, thought-provoking stories. Articles must be no longer than 700 words and previously unpublished. Only…

GALILEO Currently under development by the European Space Agency and the European Union, the €5bn (£3.8bn) Galileo system (pictured below) will be accurate to one metre. The system will eventually consist of 30 satellites, of which just under half are already in orbit. It is due to reach initial operational capacity next year, with the network complete by 2020. COMPASS COMPASS, aka BeiDou-2, supersedes the BeiDou network, which provides satellite location services within China and the surrounding region only. Ten of its eventual 35 satellites are already in orbit and it should be fully operational by 2020, offering 10m resolution to civilians and 10cm resolution to the Chinese military. GLONASS GLONASS (pictured below) is Russia’s GPS. Construction of the satellite network began in 1976, and was completed in 1995. GLONASS…

In January, surgeons at Angers University Hospital in France successfully removed a brain tumour from a cancer patient with the aid of virtual reality (VR) goggles. Such operations often need to be carried out while the patient is conscious so surgeons can see which parts of the brain are functioning properly. However, as certain brain regions require specific stimuli to activate, it’s not always possible to observe the brain carrying out particular functions while the patient is on the operating table. By placing the patient in a VR environment, however, the French surgeons were able to replicate specific circumstances (in this case, bright objects in the patient’s peripheral vision) that stimulated the brain in the region from which the tumour was being removed. “By controlling what the patient sees and…

“WHEN THE TRIBE LAUGHS AT YOU, THEY’RE REALLY TELLING YOU NEVER TO DO THAT AGAIN” Which will come first: a universal theory that unites quantum mechanics and the General Theory of Relativity, or a scientifically scrupulous theory of humour, where laughter and the underpinning of all jokes is explained in a single, pithy sentence? My money remains on the universal theory. “Why are they laughing?” is the question of the paranoid man and the lecturer in anthropology. Humour studies is accused of being humourless, but it’s still fun to think about what makes something funny. Unlike biochemistry or cosmology, I don’t think an objective and scientifically accurate theory of comedy is necessary, though jokes canhelp us to understand the structure of our brains, the nature of artificial intelligence and what…

1. IT DEPENDS ON THE GUN Experiments using ballistic gelatine to mimic the human body suggest that a 9mm bullet from a handgun will penetrate about 60cm through human fat tissue. A fully jacketed bullet from an assault rifle, such as an AK-47, will go much further and can easily shoot through a brick wall. 2. NOBODY IS THAT FAT A morbidly obese person weighing over 125kg might have 60cm of fat at the thickest point, including subcutaneous fat and the fat that surrounds their organs. But no one has that thickness evenly across their entire body. Even a blue whale’s blubber is only 30cm thick. 3. DO YOU FEEL LUCKY? In 2010 Samantha Lynn Frazier was hit by a stray bullet in a shooting in Atlantic City, New Jersey.…

1. Chlorofluorocarbons (CFCs) are organic molecules with a low boiling point. Before they were discovered to deplete the ozone layer, CFCs were widely used as the refrigerant gas in fridges. 2. The company that first used CFCs in fridges was Kinetic Chemicals, owned by General Motors and DuPont. They trademarked their particular blend of CFC compounds as ‘Freon’ (pictured) in 1930. 3. In 1938, a DuPont researcher called Roy Plunkett found his gas cylinders of the CFC tetrafluoroethylene were clogged with a white slippery substance. The iron cylinder was catalysing the CFC into polytetrafluoroethylene (PTFE). 4. DuPont trademarked PTFE as Teflon. It wasn’t until 1954 that French engineer Marc Grégoire tried using it as a non-stick coating on frying pans. The company Tefal was named after ‘Teflon’ and ‘aluminium’.…

“TAKE A MOMENT TO THINK ABOUT THE FLUID IN YOUR BATHROOM, SHIFTING IN A SLOW WALTZ” When I was an undergraduate, one of my lecturers told tales of the geological discoveries that had been made by accident, of the many times when someone saw something odd but important while they were supposed to be focusing on something else. This is one of the strongest arguments for carrying out experiments, rather than just thinking about problems. You never know what the world is about to show you. This month, I did a demonstration for my students that turned out to be much more interesting than I’d expected. I spend far too much time in shops tilting bottles of shampoo to assess how slowly the liquid flows. That’s because buying colourless shampoo…

Both my father and grandfather were doctors, so in a way I was destined to become a medic too. But before I studied medicine, I studied psychology and became a musician. I played the clarinet, saxophone and drums. For a long time, I considered myself a professional jazzer and an amateur medic! My first medical job was at a homeopathic hospital in Munich. When you are studying medicine you don’t have time to think critically because there is so much to take in, so I was actually quite impressed with what I saw. When I took a job as a researcher, it changed my life. It turned me into a scientist and a critical thinker. I never look for controversy, but there have been a few times when I’ve found…