Indholdsfortegnelse for Christmas 2018 i BBC Science Focus Magazine

MSG’s no good for me I found your feature on monosodium glutamate (November, p101) to be of great interest, as I am allergic to this substance and it is dangerous to me. If I ever eat a Chinese meal, my eyes start to water and my throat closes over to a dangerous extent. I have no other allergies and this one is listed on my hospital notes. I may be in a small minority, but this substance is not harmless. I miss my favourite takeaway, but I won’t risk such a HTKIJVGPKPI›GZRGTKGPEG››| Bill Leahy, via email Why north? I very much enjoyed your article on the proposed British spaceport in Scotland (November, p76). The story was missing one important element, though, in my opinion. That is, what is the logic/benefit,…

How much does a kilogram weigh? It’s a simple question with a complicated answer – and next May, that answer is changing for the first time in over a century. As it stands, a kilogram is defined by a lump of metal kept in a safe in Paris. Officially called the International Prototype of the Kilogram (IPK), but more affectionately referred to as Le Grand K, it’s a cylinder made from a platinum-iridium alloy that has defined the kilogram since 1889, when it was officially sanctioned and put into storage at the International Bureau of Weights and Measures (BIPM) in France. There are also several copies of it around the world – the UK’s specimen is held by the National Physical Laboratory (NPL) in Teddington. Before the metric system was…

The picture below shows the moment two become one: astronomers have caught the first images of black holes combining to form the cores of new galaxies. A team led by Eureka Scientific’s &T›/KEJCGN›-QUU›WUGF›VJG›9/|-GEM› Observatory in Hawaii, the Hubble Space Telescope, and the Burst Alert Telescope (BAT) aboard NASA’s Neil Gehrels Swift Observatory, to find and photograph several pairs of merging black holes. Coalescing galaxies have been spotted before, but only in their early stages. The final stage of the process, in which their respective black holes merge, has never been imaged before because it occurs behind the enormous, dense cloud of gas and dust that is produced as each of them consumes the surrounding material. The team was able to overcome this obstacle with the help of X-ray data gathered…

Cotton Eye Joe hasn’t got anything on this guy: a set of footprints left by a sidestepping reptile-like creature have been discovered covering a fallen boulder along the Bright Angel Trail in the Grand Canyon, Arizona. The tracks were first discovered in 2016 by a group of hikers, who then alerted Prof Stephen Rowland, a geologist at the University of Nevada. The tracks are estimated to be around 310 million years old, and date back to a time when the supercontinent Pangaea was being formed, making them the oldest ever found in the Grand Canyon. “My first impression was that it looked very bizarre because of the sideways motion,” said Rowland. “It appeared that two animals were walking side by side. But you wouldn’t expect two lizard-like animals to be…

COMPUTING THE BROADENING REACH OF MACHINE LEARNING Machine learning is the process of feeding data into a program so that it ‘learns’ how to perform a certain task, without engineers having to explicitly program an algorithm. A few years ago, companies like Google and Microsoft open-sourced their machine learning platforms, allowing anyone to apply machine learning tools to their own projects. This year, we’ve really started to see the fruits of those accessible platforms, with machine learning applied to a wider range of tasks that ever before. Machine learning is now being used, for instance, to detect the sounds of illegal logging in the rainforest, monitor the health of dairy cows, and detect cancer cells that are too small for pathologists to see. However, machine learning isn’t without its share…

Here’s a delicate truth: we’re all approaching the ends of our lives. Every day counts us down, it’s just that most of us rarely talk, or even think, about it. And when we do, we feel scared of pain and panic and feeling out of control; afraid of sadness and saying goodbye; worried about deaths we’ve seen on TV or in films. I’ve worked in palliative medicine for over 30 years, helping to improve the conditions of those nearing the ends of their lives. I’ve sat by the bedsides of scores of dying people and it’s taught me a lot about the realities – and misconceptions – of death. More than half a million people die in the UK each year and almost all of them from a condition that…

The opening sentence of LP Hartley’s The Go-Between is, “The past is a foreign country: they do things differently there.” But a similar claim has been made by a group of astronomers. For 20 years, they have been suggesting that the laws of physics in the early Universe differed subtly from today’s. And in the next few years, a new generation of astronomical instruments will put this controversial claim to the ultimate test. The feature of physics which is claimed to have changed is the ‘fine-structure constant’. Known as ‘alpha’, it dictates the strength of the interaction between electrically charged particles and photons of light. Since such an interaction is the source of electromagnetism, it governs the strength of the electromagnetic force. Alpha is vital to our existence. If it…

As someone who writes about food and health, I’m sometimes asked what the modern equivalent of the health crisis caused by smoking will be. What are we doing now that we will look back on in horror, and ask ourselves ‘how did we not see the harm’? My answer is dieting. I believe that in 50 years’ time, our grandchildren will ask us why we thought that short-term starvation was an effective way to permanently alter our weight. And they might also ask us how we became so obsessed with making the wonderfully diverse set of human bodies exactly the same shape and size. In the UK, almost half of us will have attempted a weight loss diet over the past year. Studies suggest that almost all dieters will eventually…

Do you remember the first time you experienced ASMR? The ASMR sensation has always been part of my normal sensory experience and I don’t remember a ‘first time’. If you are ASMR-sensitive then you have it right from early childhood. The main experiences I remember as a child were eye tests, haircuts, having my back drawn on and listening to the teacher read a story in school. How did you get started making videos? I first discovered that ASMR videos existed on YouTube after a car accident and subsequent PTSD. I was struggling to sleep and looked on YouTube for relaxation videos. My life changed so much once I realised there was a name for the feeling I had experienced my whole life! Finding out that others experienced it and…

CRUST 0-200KM DEEP The surface of the Earth is made of rigid yet flexible tectonic plates. Continental plates are old and light, composed of low-density minerals rich in silica. Continental plates average 15 to 30 kilometres thick, although the most ancient plates can be up to 200 kilometres thick. Oceanic plates are younger and denser, composed of high-density minerals rich in iron and magnesium with little silica. At just 7 to 10 kilometres thick, they are thinner than continental plates. MANTLE 30-2,890KM DEEP The thickest layer of the Earth consists of hot, ductile rock rich in iron and magnesium. Over millions of years, the mantle flows in enormous convection cells (shown here by yellow arrows) that drive plate tectonics and feed hot spots below volcanoes. Diamonds form in the upper…

Prof Guy Gratton Aerospace engineer, and visiting professor at Cranfield University “This is very clever application of the principle of ion thrusters to an aircraft, using high voltages to ionise then accelerate the air at high speeds. So far they have only been used on spacecraft, usually to help a satellite stay in position in orbit. “It’s clearly early days, but the team at MIT have done something we never previously knew was possible: using accelerated ionised gas to propel an aircraft. Aeronautical engineers around the world are already trying hard to find ways to use electric propulsion. This technology will offer something else that in the future may allow manned and unmanned aircraft to be more efficient and non-polluting. In particular, the fact that they have already got this…

What is ’Oumuamua? ’Oumuamua means ‘messenger from faraway’ or ‘a scout that arrived first’, in Hawaiian. It’s the first object ever discovered in the Solar System that comes from outer space. We can tell that because it’s moving too fast to be bound to the Sun gravitationally. What’s so unusual about it? It appears to have an extreme shape that’s 5 to 10 times longer than it is wide, based on the reflected sunlight. If it’s a perfect reflector, it’s at least 20 metres in size; if not, then it’s hundreds of metres in length. So it doesn’t look like any asteroid we’ve ever seen. It also deviates from the orbit that we’d expect based on the Sun’s gravity, and that’s due to some extra force acting on it. For…

When I first met LC, she was 25. She had a beautiful memory, I was told, and beautiful memories are my research hobby. LC could remember her life as a rich, flowing narrative: the colours of her clothes, her exact conversations, the minutiae of her daily routine. But there was a glitch. Her beautiful memory spanned only between the ages of 9 and 14, and it only covered events related to her devout Catholic faith. During those times, she could remember everything, but the rest was as scattered and vague as it is for any of us. LC’s case may seem peculiar, but she was just doing an extreme version of what we all do every day: building a story of our past. We all need a personal history in…

“We could get around the restrictions of natural selection and accelerate evolution using a ‘gene drive’” Natural selection only makes features more common if they help organisms survive or reproduce. But we could get around that restriction by accelerating evolution using something called a ‘gene drive’. Gene drives are bits of DNA that work by breaking the laws of inheritance. Many organisms inherit genes on pairs of chromosomes, one from each parent, so their offspring have a 50/50 chance of inheriting either the maternal or paternal copy of any given gene. But a gene drive can copy-and-paste its DNA sequence from the chromosome carrying it to the other chromosome, ensuring the drive is passed on to 100 per cent of an organism’s offspring. Over multiple generations, the drive rapidly spreads…

Can you describe the sensation of ASMR? It travels up into my head and it feels like it’s glowing. Then it kind of trickles down the spine and goes up and down. I imagine it as lights going on and off up and down the spine like a ripple. It’s so good. Do you remember the first time you felt it? Definitely – I was 12 or 13, and it was the first time I listened to music using headphones. I was lying on my front in bed, and it was dark because the lights were out. I was listening to Christina Aguilera’s The Voice Within. There’s this incredible bit towards the end, it’s so passionate and heartfelt and her voice is amazing. What kinds of experiences trigger the sensation…

Why might we need arti›cial wombs? Researchers hope that artificial wombs will increase the survival chances of extremely premature babies, allowing the babies to develop as if they’re still inside the mother. In 2017, paediatric surgeons at the Children’s Hospital of Philadelphia in the US revealed a new technique that involves suspending the foetus in a ‘biobag’ full of synthesised amniotic fluid. They’ve so far tested the device on premature lambs, attaching the animal’s umbilical cord to a gas exchange machine outside the bag that keeps the blood topped up with oxygen and nutrients. Some of the lambs were kept alive up to birth weight, so if the team can make this technology safer, they may be able to adapt it to save human babies. What does a baby get…

What is the time resolution of our senses? LILLIA NELSON (AGE 10), HAMPSHIRE When you watch a film, the cinema projects a series of still frames one after the other, but you perceive it as continuous motion because each frame is only shown for about 40 milliseconds. In fact, under ideal conditions we can spot a flicker in a light even if it lasts for just 25 milliseconds. Our other senses react at different speeds, though. Hearing is much faster, with a time resolution of just three milliseconds, but touch can only manage 50 milliseconds. Smell and taste are the slowest and can take more than a second to react to a new sensation. LV…

Bitey mite SAINT PIERRE , RÉUNION A tiny Varroa destructor mite clings to the hairs next to a honeybee’s eye (seen here on the right). Female mites attach to adult bees, sucking their haemolymph (insect ‘blood’) and spreading viruses. To make matters worse, when the bee returns to its hive, the mite crawls off into a brood cell containing a bee larva and gets itself sealed inside, where it lays its eggs. When the young mites hatch they feed on the developing bee pupa, which later emerges from its cell weakened or deformed. “Mites can be controlled chemically and by dusting the bees with fine powders,” says entomologist Prof Adam Hart. “But perhaps the best method is to breed bees that remove infected pupae from the brood cells before the…

Well, this has blown some of the current thinking out of the water! Asteroids typically get all the credit for bringing H2O to Earth, but a new study suggests they may have to share the limelight with another source – the solar nebula, the cloud of gas and dust that eventually coalesced into the Sun and the rest of our Solar System. Scientists from Arizona State University researching the chemical composition of Earth’s water have found that some of it doesn’t match the profile of the ice that arrived in asteroids. By checking the ratio of hydrogen to deuterium (a hydrogen atom containing an extra neutron) in water samples, the team could determine the water’s likely source. The ratio of hydrogen to deuterium in ocean water is a good match…

What did they do? Researchers at the University of the Arts in Bern, Switzerland blasted a batch of maturing Emmental cheese with a mix tape that included tunes from classic rockers Led Zeppelin, hip-hop legends A Tribe Called Quest and excerpts from Mozart’s opera The Magic Flute. Why did they do that? Some gardeners have long maintained that talking to their plants, or even playing them music, helps them to stay healthy and grow more quickly. And believe it or not, there is a small area of research known as sonochemistry in which researchers investigate the effect of exposure to ultrasound on chemical reactions. The team wanted to see if sound waves could affect the chemical processes going on within a cheese as it matures. What did they find? The…

There’s a new recipe for clean energy: take some cyanobacteria, add mushrooms, produce power. The correct combination of ingredients was discovered by researchers at the Stevens Institute of Technology in New Jersey, who were investigating ways to exploit cyanobacteria’s ability to generate electricity. Cyanobacteria proliferate in Earth’s oceans and produce energy by photosynthesising sunlight. But we’ve so far been unable to exploit their energy-producing ability, because the microorganisms can’t live on the artificial surfaces needed to draw an electric current. Mushrooms, however, naturally host a variety of microorganisms. Dr Manu Mannoor and Dr Sudeep Joshi, two engineers at the Stevens Institute, wondered if the fungi could provide the right habitat for the cyanobacteria to survive and produce electricity. “WE SHOWED THAT A HYBRID SYSTEM CAN INCORPORATE AN ARTIFICIAL COLLABORATION BETWEEN…

1 ROBO BUDDY Research shows that 41 per cent of us feel we’re talking to a friend when speaking to Siri etal, so Anki made its new digital assistant a cute little robot who responds to voice commands and does a happy shimmy when he gets things right. Anki Vector £199.99, anki.com 2 VR FOR THE MASSES Oculus Go rings in a new era for VR, where you don’t need to tether to a PC or slip your smartphone into a headset. It’s a fully contained VR system, so just slip on the headset and go. Plus, it’s at a cost that makes it more realistic for the masses. Oculus Go £199, oculus.com 3 DEVICE DEN Smartphones and tablets can help kids…

What in your opinion is the greatest engineering breakthrough of recent times? Start up of the Large Hadron Collider? Elon Musk’s self-landing rockets? 3D printing? Of course, there’s no simple answer. You see, technical evolution is subjective; how much does progress in that field resonate with you? By how much will it improve your life? if that field involves travelling faster and further, while protecting the planet and liberally sprinkling fun, Specialized’s new Turbo Levo electric mountain bike will ring loud and clear… Nineteen of the world’s leading engineers united at Specialized’s Turbo Innovation Centre in Switzerland to research, design and forge the most technologically advanced bicycle in the world. That 19 included a trio of innovators who've redefined what it means to cycle, namely team lead Vincent Patureau, electronics…

Bacteria do many things for us – from making our food and fuels to breaking down waste. But research suggests they could also determine whether or not it rains. The microorganisms that affect weather are known as ice-nucleation active bacteria. They are often found on crops and can cause plant disease. They have special proteins on their surface that help water in the air turn to ice at slightly warmer temperatures – around -3°C instead of -8°C. On the ground, these proteins can cause frost damage to crops. But when the bacteria are blown into the sky, they can cause ice crystals to form in the atmosphere – a crucial first step in the creation of rain or snow. The process, called ‘bioprecipitation’, was once thought to play only a…

Deep below the surface of our planet, an ocean lurks. It’s a secret world of water we only know about because of an unlikely messenger: diamonds. The rocks we see and interact with every day – mountain ranges, crumbling coastal cliffs, maybe the soft sediments and soils that line valley floors – are only a small portion of all the rocks on Earth. In-between the surface of the planet and the iron-rich core is the mantle, a warm, thick, gooey layer of rocks that flows like plastic. This is where the diamonds grow, hundreds of kilometres down. As the gemstones form, they freeze a moment of deep mantle geology, and when they arrive at the surface, scientists can poke and prod at them to understand more about the conditions within…

Alcohol is dangerous. Its abuse accounts for around 8,000deathsintheUKeveryyear,whilethesocietal cost – in terms of the strain on the NHS and the police – is enormous. It costs £3.5bn a year for the NHS to treat alcohol-related illnesses and injuries, while 70 per cent of violent incidents occurring during the evenings, nights and weekends involve alcohol. Many people are, of course, able to enjoy a drink without coming to any harm, or becoming addicted. But many aren’t: it’s estimated that 9 per cent of men and 3 per cent of women in the UK show signs of alcohol dependence. And if you do get hooked, the prospects aren’t great. There are many treatment programmes available, but over 80 per cent of people that complete one will be drinking dependently again within…

BCEM›KP›››››››/KEJCGN›(CTCFC[››TUV›ICXG› his famous lecture series ‘The Chemical History Of A Candle’ at the Royal Institution Christmas Lectures. In doing so, he taught young boys in the audience about the physics and chemistry behind one of the most essential items in their homes. The principle has stayed the same over the decades, with each year’s lecturer tackling contemporary topics in front of an audience of spellbound schoolkids. Now, 170 years on from discussing the science of candles, speakers have taken on topics like hacking your home, how to survive in space, and whether or not you could live forever. 9JKNG!UEKGPVK&E!MPQYNGFIG!JCU!EQPVKPWGF!VQ!KORTQXG%!VJG! presenters of the Christmas Lectures have consistently used over-the-top props and often nerve-racking experiments to get their young audience excited about the world of science. 6JGUG!"'!KVGOU!OCTM!UQOG!QH!VJG!OQUV!UKIPK&ECPV!OQOGPVU! in the history of the…