Return of the bat: European species make a comeback

Defying years of shrinking habitat and disappearing roosts, bats are making a comeback in Europe.

Bat numbers – collected from 6000 hibernation sites in nine European countries – have increased by 43 per cent between 1993 and 2011, according to a new report by the European Environmental Agency (EEA). The study, which tracks 16 of Europe's 45 bat species, is the most comprehensive population study of bats on the continent to date.

"This trend is a definite sign of hope," says Karen Haysom, director of science at the British Bat Conservation Trust, a partner in the study.

Armed with a statistical method that proved key in earlier EEA studies of European butterfly and bird population trends, Haysom and her collaborators input decades of national bat data into a dataset that revealed how bat numbers changed from winter to winter according to species and region. Never before had such data – reported by scientists and also by thousands of amateur bat enthusiasts, who counted hibernating animals in local caves and other roosts – been consolidated over such a broad time span and geography, Haysom says.

"This is giving us a chance to put our numbers in a different and very valuable context, and think about why some bat species are doing well in some countries compared with others," she says. Population trends were calculated in Latvia, Hungary, The Netherlands, Austria, Portugal, Slovenia, Slovakia, Germany and the UK.

The bat-phone

In the second half of the 20th century, European bat populations plummeted due to increased agriculture, intentional killing, destruction of roosts and exposure to roofs treated with a pest-repellent called dieldrin. The decline was further fuelled by bats' naturally long lifespan and slow reproduction rate, Haysom says.

But recent conservation efforts including cave protection, bat-friendly farming practices, local bat-assistance hotlines – bat-phones, if you will – and educational campaigns like local "bat walks" may have helped turn the tide.

The EEA team found that nine bat species, including Daubenton's bat (Myotis daubentoni ) and the Mediterranean horseshoe bat (Rhinolophus euryale ) have increased, while several others held stable.

Citizen science

"Though the report is heartening, the job is certainly not done," Haysom says. For instance, the grey long-eared bat (Plecotus austriacus ) showed a continent-wide decline.

Bat specialist Paul Racey of the International Union for Conservation of Nature says the project demonstrates the power of citizen science in animal conservation efforts.

"To count butterflies or birds on a nice summer's day is one thing, but counting bats hibernating in dark, damp, cold places – that's a totally different ball game," he says. "And yet, amazingly, thousands of volunteers and thousands of sites in Europe were committed to the work."

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Read More

Black bloom in the Atlantic skirts Brazil's coast

(Image: NASA)

What is this dark stain reaching along Brazil's Atlantic coast to São Paulo? It showed up in a recent satellite photo, stretching nearly 800 kilometres across the ocean.

The snapshot was taken on 19 January by Aqua, a NASA spacecraft designed to track the Earth's water cycle. Local biologists say the black bloom is made up of hosts of a microscopic animal called Myrionecta rubra. Seen close up, the bloom is deep red, but the play of light on the ocean means it looks black from orbit.

Such blooms sometimes represent a serious threat to marine life, and they have even spurred the development of ultrasound weapons to kill them off.

Is this Myrionecta bloom as ominous as it looks? The animal lives a couple of metres under the water's surface, and it's a thief. It survives by preying on algae, gobbling up their chloroplasts so it can do its own photosynthesis. However, it poses little threat to other animals.

Pockets of water closer to the Brazilian coast appear bright green – probably algae or sediment – while white clouds streak over land and sea.

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Read More

Mud dump in Great Barrier Reef park could choke life

Australia will dump millions of tonnes of sludge inside the Great Barrier Reef Marine Park so that it can export more coal. And that could be just the beginning.

Plans to start mining and exporting coal from one of the country's biggest deposits – the Galilee basin – require the expansion of the Abbot Point shipping port in north Queensland, within the boundaries of the famous marine park. In December, the federal government gave the go-ahead for this.

Since then, conservationists, fisheries and scientists have been pleading for the 5 million tonnes of soil and sediment that will be dredged not to be dumped back into the marine park.

But today, the Great Barrier Reef Marine Park Authority – the agency mandated to protect the park – approved the dumping, which is most likely to be at a location near Bowen, 25 kilometres south-east of Abbot Point.

Smothered coral

The decision comes despite more than 230 scientists signing a letter to the head of the authority asking for the dumping to be stopped. "The best available science makes it very clear that expansion of the port at Abbot Point will have detrimental effects on the Great Barrier Reef," the letter said. "Sediment from dredging can smother corals and seagrasses and expose them to poisons."

The federal minister for the environment, Greg Hunt, says a series of conditions on the development, including funding for programmes to support the health of the reef, will mean that the water quality will actually improve by 150 per cent. "The conditions I have put in place for these projects will result in an improvement in water quality and strengthen the Australian government's approach to meeting the challenges confronting the reef into the future," he said in a press release.

"I think that sounds ridiculous," says Selina Ward, a coral reef ecologist from the University of Queensland who co-authored the petition. She says an enormous amount of work has gone into improving water quality over the last two years, and 360,000 tonnes of sediment has been removed from the water. To offset the 5 million tonnes the Abbot Point extension will dump would cost about A$500 million (US$430 million) and unimaginable effort, she says.

Sediment choke

Sediment, which can travel long distances, will kill seagrass, exacerbating the decline in dugong populations that feed on it. The destruction of seagrass could also trigger the release of vast amounts of carbon stored under it.

Corals will also be affected. Many species get almost all their energy and nutrients from the algae that live symbiotically on them. When increased sediment stops light from getting through the water, the algae stop growing, weakening the coral.

The bigger port will lead to a rise in ship traffic, which increases the chance of a collision with the reef or with other marine life, Ward says.

The decision may mark the beginning of a series of dredging projects along the Great Barrier Reef coastline, says Jon Brodie from James Cook University in Queensland. For example, Abbot Point could be expanded further to accommodate the Alpha North Coal Project, another recently approved scheme to extract and export coal from the Galilee basin. Brodie says that if you add up all the proposed dredging along the reef, it will come to 140 million tonnes of sediment over the next decade.

Brodie says he is not against the ports, and notes that there are alternatives to dumping the dredged soil. Although they are expensive, long jetties can be built into deep water to avoid dredging altogether. Or if dredging goes ahead, it can be secured behind seawalls. "They just want to do it as quick and dirty as possible," he says.

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Read More

Today on New Scientist

Threatwatch: Mother virus of China's deadly bird flu

Ten years after H5N1, yet more deadly bird flu has emerged from China. Is it time to do something about the virus spawning them all?

Green sky thinking: Astronomy's dirty little secret

Astronomy produces a lot of carbon emissions, but it could be one of the greenest sciences if observatories harness their solar and wind resources

Star next door may host a 'superhabitable' world

The closest star to the sun, Alpha Centauri B, is just the right type to host a planet even better suited to life than Earth

Give the gift of life by donating your medical records

There are huge benefits to using confidential records in England for research purposes, says charity leader Sharmila Nebhrajani

Feedback: And then there were lawyers

First the polar bears whimpered and then there were lawyers, wandering pole problem, the internet before its time and more

Too much sugar in food? Follow the salt solution

The food industry is already weaning us off salty food. Time to follow suit with the sweets

Healthy-weight toddlers protected from later obesity

Young children that don't become overweight are at less risk of future obesity, researchers say – so what's the best way to keep under-5s a healthy size?

First graphene radio broadcast is a wireless wonder

IBM's successful transmission to a radio chip made using graphene hints at the cheaper, less power-hungry wireless devices of the future

First glimpse of how HIV swamps the gut's immune cells

Researchers have captured high-resolution, 3D images of HIV virus lurking in the intestines of mice with "humanised" immune systems

First brain map of speech units could aid mind-reading

The map is the first to show brain areas devoted to distinct types of phoneme – it could allow what someone is hearing to be read from a brain scan

Conversation app helps parents boost child's language

A smartphone-based system that listens to parents talk to their child can build the child's language skills by offering the parents cues in real time

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Read More

Threatwatch: Mother virus of China's deadly bird flu

Threatwatch is your early warning system for global dangers, from nuclear peril to deadly viral outbreaks. Debora MacKenzie highlights the threats to civilisation – and suggests solutions

Exactly 10 years after H5N1 bird flu exploded across south-east Asia, the virus is still widespread, and has been joined by new killer types of bird flu. Human cases of H7N9 flu are surging in south-east China, and a new type of bird flu, H10N8, has claimed its second human victim, in the same region.

Now it seems that all of these viruses stem from a single, mother virus. Targeting it might stop it from spawning new, deadly viruses in the future.

Few people have heard of H9N2, but this virus was crucial in giving rise to the three dangerous bird flu viruses that have emerged so far in China – H5N1, H7N9 and H10N8.

None of these viruses has yet evolved the ability to spread readily in people and potentially trigger a pandemic – although we know H5N1 can, and H7N9 and H10N8 seem similar. But even if those viruses never go rogue, their cousins might, because the real problem is their common ancestor, which endowed them with the genes that make them dangerous.

The enabler

"H9N2 is the enabler, the one to worry about," Robert Webster of St. Jude Children's Research Hospital in Memphis, Tennessee, told New Scientist. Bird flu is usually a gut infection in ducks, but H9N2 has evolved into a benign respiratory virus in chickens that has spread across Eurasia. When multiple flu viruses infect the same host, they can swap genes. They may be named for their various H and N surface proteins, but H5N1, H7N9 and H10N8 all got some or all of their "internal" genes from H9N2.

Those genes – for the enzymes that replicate the viral genome, for example, or a protein that confuses a host's immune system – can make these viruses dangerous, says Webster. Any of them might become pandemic if they acquire the right mutations to spread in people – or hybridise with a normal human flu.

Closing Asia's ubiquitous live poultry markets would be the key to controlling N9N2, says Webster, as this is where H9N2 and its spin-off viruses spread, mingle and evolve – and where humans catch them.

That is just what China is trying to do. As millions celebrate Lunar New Year this week with home-slaughtered poultry, Shanghai and three other cities have shut their live markets and officials are urging people to eat pre-slaughtered, frozen birds. The continued threat from China's bird flu may depend on whether that catches on. "It's the Year of the Horse in China," says Webster. "I hope they can get the stable door closed before the horse has bolted."

Back with a vengeance

H7N9 emerged in south-east China last spring, infecting 136 people, a third of whom died. In response, Chinese flu scientists called for live poultry markets to be shut last April. Some were – but they were re-opened when flu cases dropped in the following months.

The virus returned with a vengeance at the end of last year, however. So far 131 more infections have been reported since October last year. Caitlin Rivers of Virginia Tech in Blacksburg, Virginia, has modelled the spread of H7N9, and says she is convinced that poultry markets are a primary driver of the outbreak.

Now the affected area is growing and south-east China is reporting some half dozen new cases per day, so the call to close markets is strengthening. China's National Health and Family Planning Commission announced this week that live markets should close if they harbour H7N9, after the country's Ministry of Agriculture confirmed that the virus is mainly found in these markets, rather than on farms.

Killer in the family

But H7N9 is not the only problem. The latest killer in the family, H10N8, took the life of a 73-year-old woman in December last year, and now a 55-year-old woman is critically ill with it after visiting a live poultry market. "We know very little about H10 viruses," says Richard Webby, also at St. Jude, and there may be other new viruses that have not been detected yet.

Meanwhile, H5N1 still circulates in Chinese poultry – silently, because it can spread in vaccinated birds without causing obvious disease. A Canadian woman died of H5N1 flu this month after flying home from a visit to Beijing, even though the city has not reported a case of H5N1 in years.

Shanghai and three cities in Zhejiang Province, the hardest hit by the current outbreak of H7N9, have now temporarily shut their live markets. Officials from one of these cities, Hangzhou, say they want to make the closure permanent, and switch to frozen, centrally slaughtered poultry. Zhang Yonghui, head of the Guangdong Centre for Disease Prevention and Control, told China's official news service Xinhua this week that the government should switch the country to such industrial chicken slaughter.

That will not be easy. Hopes that the temporary market closures of last spring would become permanent were dashed when consumers demanded their re-opening. "I can understand the difficulty," says Webster. "Culturally, the Chinese must eat freshly slaughtered poultry on New Year's Day," and they tend to prefer it at any time.

But the risks, he says, have become too high. The world now waits to see what the future holds for China's chickens.

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Read More

Too much sugar in food? Follow the salt solution

ANYONE who worries about their diet must have had a few anxious moments about sugar in recent weeks. The media has been full of stories about its effects on health, from obesity and diabetes to liver disease. Some stories were exaggerated, but many got it right (see "Sugar on trial: What you really need to know").

It's hardly news that sugar is bad for you, so why the sudden interest? One underappreciated reason is the success of a public health battle against another white crystalline powder.

Around 20 years ago a small group of cardiovascular specialists in the UK decided to do something about the large amounts of salt being added to processed food. As a result of their campaign, people in the UK now eat around 15 per cent less salt than they used to, preventing thousands of deaths a year from strokes and heart attacks.

How did they do it? The answer was to work with the food industry, not against it. The campaigners persuaded manufacturers to gradually reduce the amount of salt in processed foods. The aim was to wean people off salt. It worked: people in the UK now prefer foods with less salt. That success is being replicated worldwide.

Salt is still a problem, but the salt campaigners have made enough progress to turn their attention to sugar. There are reasons to believe that the anti-salt tactics will work again. Like salt, sugar leads to habituation. The more you eat, the less sensitive your taste buds become to it, so gradual weaning should work.

Salt reduction has shown that the food industry can do the right thing for public health. Sugar is a problem on a similar scale. The industry can – and should – help to solve it.

This article appeared in print under the headline "Look to salt success to reduce sugar"

• New Scientist


• Not just a website!


• Subscribe to New Scientist and get:


• New Scientist magazine delivered every week


• Unlimited online access to articles from over 500 back issues


• Subscribe Now and Save

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Read More

Healthy-weight toddlers protected from later obesity

Prevent obesity in the under-5 and the benefits can last years. This was the message of a widely reported study published this week. So how do you help youngsters maintain a healthy weight?

The new study involved 7700 children and was led by Solveig Cunningham of Emory University in Atlanta, Georgia. Her team showed that if children reach their fifth birthday without becoming overweight or obese, their chances of developing obesity as a teenager are reduced fourfold. The researchers conclude that obesity might be best tackled by focusing on measures to prevent it in the pre-school years (NEJM, doi.org/q9n).

Perhaps the first place to begin tackling childhood obesity is before the child is even born. Studies suggest that taking action to correct poor lifestyle choices and poor diet in mothers – both before and during pregnancy – could affect the fetus and decrease the resulting child's subsequent vulnerability to obesity.

For instance, a study led by Julie Dodd at the University of Adelaide in South Australia showed that dietary management of pregnant women who were themselves obese – a risk factor for having overweight babies – reduced by 14 per cent the likelihood that their babies would be heavier than 4 kilograms (9 pounds) – a weight that, in Australia, puts a baby among the heaviest 10 per cent.

"Genetics plays a role, as does epigenetics – the programming of genes in the fetus," says Elsie Taveras of the Massachusetts General Hospital in Boston, who co-authored an editorial in the NEJM commenting on Cunningham's results this week. "The fetal environment may therefore have impacts which predispose the baby to be especially vulnerable to rapid weight gain."

Resetting expectations

After the birth, focus might shift to the quality – and quantity – of a baby's diet. Here, reducing the protein content of infant formula so that it matches that of breast milk is proving effective. A 2009 study led by Bert Koletzko of the University of Munich Medical Centre in Germany showed that babies grew just as long but were 20 per cent lighter if fed on low-protein rather than high-protein formula. They also matched the weight-gain patterns of breastfed babies more closely. "It's cheap and easy, and all it takes is changing the recipe," says Koletzko.

Meanwhile, Ken Ong at the University of Cambridge is leading a study to give behavioural support to mothers whose babies are growing exceptionally fast through overfeeding. The idea is to try to help them bring their babies to more normal rates of growth.

"It's not just telling mothers how much to feed, but re-setting their expectations about what's healthy growth," says Ong, who has so far recruited 400 of the target 700 mothers he needs to begin the study.

Historical hangover

Historically, says Ong, one of the problems has been that fast weight gain has been seen as a good thing. This was not helped by earlier birth growth charts, which actually encouraged overfeeding. Based on formula-fed babies, the charts have now been replaced by the World Health Organization to reflect healthy weights calibrated by breastfed babies.

It's not all about diet, though: the environment around a baby or young child is a factor too, says Taveras. Trying to introduce regular sleep patterns and avoiding exposure to fast-food advertising on television can help.

"We published a study in September showing that introduction of healthy routines to households at risk had a significant impact within six months," says Taveras. "Body mass indexes were half a unit lower in the intervention group than in the control group. This is large enough to make the difference between being classed as obese or overweight, or between being overweight and normal weight."

The good news is that these strategies appear to be bearing fruit: rates of childhood obesity in the US and elsewhere in the world are showing signs of falling.

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Read More

First graphene radio broadcast is a wireless wonder

Three letters beamed across a lab bench may spark a revolution in wireless communication. The seemingly simple transmission of "IBM" was received by the first working radio chip to be made from the modern wonder material, graphene – sheets of carbon, each just one atom thick.

Graphene, with its flat, hexagonal lattice, was first isolated a decade ago. It won its discoverers a Nobel prize in physics, in part because its high electrical and thermal conductivity led to broad predictions that it would completely replace silicon transistors, the key component in many electronics. This latest achievement shows that analogue circuits such as radios can indeed make use of the material, potentially leading to cheaper, more efficient wireless devices.

Until now, making wireless circuits like the ones in Bluetooth and WiFi chips has not been possible with graphene transistors, because it is too delicate a material and only weakly adheres to the standard silicon base. In 2011, IBM researchers made a radio microchip with graphene transistors, but they found that placing other necessary metal components, such as resistors and coils, on top of the transistors physically damaged them. This seriously degraded their ability to amplify voltages – a key requirement when attempting to boost feeble radio signals – and the team was not able to receive a broadcast.

"Taming this new material so we could process it properly, and without damaging it, became our biggest challenge," says Supratik Guha, IBM's director of physical sciences at the company's lab in Yorktown Heights, New York. With funding from the US Pentagon's Defence Advanced Research Projects Agency (DARPA), a team led by IBM's Shu-Jen Han has found the answer: make graphene-based chips in reverse.

Reverse the flow

The team found that if they place the metal components on the chip first and then add the graphene transistors, the devices do not suffer the same structural stresses and damage as the 2011 chip. "We found that simply by reversing the flow of the manufacturing process, the gain of graphene transistors is now 10,000 times better than before," says Han. The team built the chips on standard silicon wafers, suggesting no major changes in production technology will be necessary.

To test the circuit, the team sent a radio signal containing the letters I, B and M, and the device received it perfectly, its makers claim. Graphene's high conductivity means the graphene circuit uses less power than traditional radio chips, which makes it attractive for use in the wearable radio devices DARPA wants for the US military.

Feverish research competition in the graphene arena meant a spokesman for a rival lab preferred to comment anonymously on IBM's work. The result is impressive, he says. He still thinks it will be at least 20 years before graphene chips become commonplace, and even then devices like IBM's, which mix graphene and silicon, will have the best shot at success.

Journal reference: Nature Communications, DOI: 10.1038/ncomms4086

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Read More

First glimpse of how HIV swamps the gut's immune cells

Video: First glimpse of how HIV swamps the gut's immune cells

We've been given the first glimpse of HIV in attack mode in the gut, shedding light on how the virus hijacks immune cells, multiplies and spreads throughout the body.

A team of biochemists have used electron tomography microscopes to capture the first high-resolution, 3D images of the HIV virus lurking in the intestines of "humanised" mice, whose immune systems are made up largely of human cells.

"This is the next step in studying how the virus interacts with immune cells in its natural environment, not in a Petri dish" says Mark Ladinsky, part of the team at the California Institute of Technology that carried out the work.

Although it was known that HIV hides out in the gut, Ladinsky says no one had expected to find such large pools of circulating virus.

In this video reconstruction, the team presents a sequence of intestinal cross-sections just 0.9 nanometres thick taken from a deep region of intestinal tissue that houses immune cells. These are called intestinal crypts, after their pocket-like shape.

The microscopic images are laid on top of one another to give the viewer a "zoom through" look at spherical particles of HIV virus (labelled in blue) within a small tissue volume.

Two immune cells called CD4 T-cells that have been infected with HIV lie side by side, taking up most of the frame. The HIV has commandeered the immune cells and new viruses bud from the cell surfaces to join a pool of more than 300 free, mature HIV particles circulating in the space between the cells.

In the second part of the clip, the gut tissue disappears to show only the pool of virus, which is rotated in 3D to demonstrate the spread of HIV within the intestinal crypt.

HIV house

Studying the large pools of virus in these crypts is crucial to understanding HIV's rapid spread, Ladinsky says. The intestinal tissue, which houses 70 per cent of the body's immune cells, is one of the first regions that HIV attacks. Within the first month of infection, the virus can ravage more than 50 per cent of the intestinal tissue's CD4 T-cells.

The high concentration of virus in the crypts, Ladinsky says, may help to explain the rapid immune cell destruction they cause. The crypts are a reservoir for HIV in people with the virus, he says, allowing the virus to avoid any antiretroviral drugs circulating in the blood. This makes the tissue an important focus for researchers developing therapies to flush out the virus.

Wes Sundquist, a biochemist at the University of Utah in Salt Lake City, says the study is a technical feat. Producing an image with a fine-enough resolution to see an object as small as an HIV virus is notoriously difficult to achieve for delicate tissue samples, he says.

"The next step is to try and image what HIV virus looks like in the intestines of human patients, especially in those who are taking antiretroviral drugs and those who can control it on their own," he says.

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Read More

First brain map of speech units could aid mind-reading

Video: How speech sounds activate the brain

"He moistened his lips uneasily." It sounds like a cheap romance novel, but this line is actually lifted from quite a different type of prose: a neuroscience study.

Along with other sentences, including "Have you got enough blankets?" and "And what eyes they were", it was used to build the first map of how the brain processes the building blocks of speech – distinct units of sound known as phonemes.

The map reveals that the brain devotes distinct areas to processing different types of phonemes. It might one day help efforts to read off what someone is hearing from a brain scan.

"If you could see the brain of someone who is listening to speech, there is a rapid activation of different areas, each responding specifically to a particular feature the speaker is producing," says Nima Mesgarani, an electrical engineer at Columbia University in New York City.

Snakes on a brain

To build the map, Mesgarani's team turned to a group of volunteers who already had electrodes implanted in their brains as part of an unrelated treatment for epilepsy. The invasive electrodes sit directly on the surface of the brain, providing a unique and detailed view of neural activity.

The researchers got the volunteers to listen to hundreds of snippets of speech taken from a database designed to provide an efficient way to cycle through a wide variety of phonemes, while monitoring the signals from the electrodes. As well as those already mentioned, sentences ran the gamut from "It had gone like clockwork" to "Junior, what on Earth's the matter with you?" to "Nobody likes snakes".

This showed that there are distinct areas in a brain region called the superior temporal gyrus that are dedicated to different types of sounds – the STG is already known to be involved in filtering incoming sound.

One cluster of neurons responded only to consonants, while another responded only to vowels. These two areas then appeared to divide into even smaller groups. For example, some of the consonant neurons responded only to fricatives – sounds that force air through a narrow channel, like the s sound at the beginning of "scientist". Others responded only to plosives – sounds that block airflow, like the b in "brain".

Other scientists have used neural activity in attempts to recreate what people are looking at or capture people's thoughts in the form of their inner voice.

Mystery of meaning

Mesgarani thinks that the phoneme map may make it easier to figure out what someone is hearing from nothing but brain signals. He has tried to do this before by analysing neural responses to sound in ferrets and in people. The map should make relating the brain activity to specific sounds much easier.

Sophie Scott at the Institute of Cognitive Neuroscience at University College London cautions that the way we hear language is more complicated than just lining up different phonemes. Sounds change in subtle ways when they come together, so the brain must analyse the sequence as a whole.

"I think it's a shame that they haven't taken a more realistic approach to what we know actually happens when people listen to speech," Scott said. "Information isn't located at the level of the segments, it's actually extending over the sequence."

Mesgarani agrees that how the brain turns phonemes into meaning is still unknown. "How the brain takes these basic units, and puts them together to form sub-word and words, and ultimately meaning, remains a mystery," he says. He hopes the phoneme map will one day help answer this question, too.

Journal reference: Science , DOI: 10.1126/science.1245994

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Read More

Conversation app helps parents boost child's language

A smartphone-based system that listens to parents converse with their child can build the child's language skills by offering parents cues in real time

A CHILD'S development depends on the world around them and chatting with parents is crucial. But around 1.3 million children in the US alone have trouble picking up language skills, meaning their parents must visit therapists to learn strategies to help them communicate. A app that listens to their every word might help.

The system, called TalkBetter, was designed by computer scientists at KAIST in Daejeon, South Korea, working with speech-language pathologists at Ewha Womans University in Seoul. It helps parents by listening to and analysing the ebb and flow of talk between them and their child. It then gives clinically relevant nudges to guide the interaction and improve the child's language skills.

Parents wear a Bluetooth earpiece and microphone while the child just wears a microphone, all connected to a smartphone. Software on the phone examines the exchanges between the two, watching out for when the parent speaks too fast, doesn't give their child enough time to respond, or ignores speech from the child. If any of these things happen, it alerts the parent via the earpiece.

Feedback from some of the 13 parents that took part in an early trial in Seoul was enthusiastic. "Can we buy this now? How much is it?" wrote one. The system will be presented at a computer conference in Baltimore, Maryland, this month.

Full clinical trials of TalkBetter are under way, but lead researcher Inseok Hwang at KAIST already has additional ideas for it. "We developed a preliminary app which targets and monitors group discussion, trying to give real-time feedback," he says. "If one person dominates the conversation, for instance, then the smartphone might give a gentle reminder to let others speak."

Stephen Hannon, president of The LENA Research Foundation in Boulder, Colorado – a charity dedicated to early language development – sees the potential in real-time feedback on parent-child conversations, but worries about the effect of micromanaging parents in this way.

This month, Hannon's group will employ a similar system in a bid to close the gap in language development between richer and poorer families in Providence, Rhode Island. Children growing up in low-income families in the US hear millions fewer words than their richer peers, which is thought to affect their academic development.

The Providence Talks project will use body-worn microphones and speech-analysis software to measure the amount of talking that children in poorer families hear every day. The organisation will then coach parents in how to boost home conversation. Hannon aims to enrol 2500 families in 2014.

This article appeared in print under the headline "Listen in to help out"

• New Scientist


• Not just a website!


• Subscribe to New Scientist and get:


• New Scientist magazine delivered every week


• Unlimited online access to articles from over 500 back issues


• Subscribe Now and Save

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Read More

Stem cell timeline: The history of a medical sensation

Stem cells are the cellular putty from which all tissues of the body are made. Ever since human embryonic stem cells were first grown in the lab, researchers have dreamed of using them to repair damaged tissue or create new organs, but such medical uses have also attracted controversy. Yesterday, the potential of stem cells to revolutionise medicine got a huge boost with news of an ultra-versatile kind of stem cell from adult mouse cells using a remarkably simple method. This timeline takes you through the ups and downs of the stem cell rollercoaster.

1981, Mouse beginnings

Martin Evans of Cardiff University, UK, then at the University of Cambridge, is first to identify embryonic stem cells – in mice.

1997, Dolly the sheep

Ian Wilmut and his colleagues at the Roslin Institute, Edinburgh unveil Dolly the sheep, the first artificial animal clone. The process involves fusing a sheep egg with an udder cell and implanting the resulting hybrids into a surrogate mother sheep. Researchers speculate that similar hybrids made by fusing human embryonic stem cells with adult cells from a particular person could be used to create genetically matched tissue and organs.

1998, Stem cells go human

James Thomson of the University of Wisconsin in Madison and John Gearhart of Johns Hopkins University in Baltimore, respectively, isolate human embryonic stem cells and grow them in the lab.

2001, Bush controversy

US president George W. Bush limits federal funding of research on human embryonic stem cells because a human embryo is destroyed in the process. But Bush does allow continued research on human embryonic stem cells lines that were created before the restrictions were announced.

2005, Fraudulent clones

Woo Suk Hwang of Seoul National University in South Korea reports that his team has used therapeutic cloning – a technique inspired by the one used to create Dolly – to create human embryonic stem cells genetically matched to specific people. Later that year, his claims turn out to be false.

2006, Cells reprogrammed

Shinya Yamanaka of Kyoto University in Japan reveals a way of making embryonic-like cells from adult cells – avoiding the need to destroy an embryo. His team reprograms ordinary adult cells by inserting four key genes – forming "induced pluripotent stem cells".

2007, Nobel prize

Evans shares the Nobel prize for medicine with Mario Capecchi and Oliver Smithies for work on genetics and embryonic stem cells.

2009, Obama-power

President Barack Obama lifts 2001 restrictions on federal funding for human embryonic stem cell research.

2010, Spinal injury

A person with spinal injury becomes the first to receive a medical treatment derived from human embryonic stem cells as part of a trial by Geron of Menlo Park, California, a pioneering company for human embryonic stem cell therapies.

2012, Blindness treated

Human embryonic stem cells show medical promise in a treatment that eases blindness.

2012, Another Nobel

Yamanaka wins a Nobel prize for creating induced pluripotent stem cells, which he shares with John Gurdon of the University of Cambridge.

2013, Therapeutic cloning

Shoukhrat Mitalipov at the Oregon National Primate Research Center in Beaverton and his colleagues produce human embryonic stem cells using therapeutic cloning – the breakthrough falsely claimed in 2005.

2014, Pre-embyronic state

Charles Vacanti of Harvard Medical School together with Haruko Obokata at the Riken Center for Developmental Biology in Kobe, Japan, and colleagues announced a revolutionary discovery that any cell can potentially be rewound to a pre-embryonic state – using a simple, 30-minute technique.

2014, Human trials

Masayo Takahashi at the same Riken centre is due to select patients for what promises to be the world's first trial of a therapy based on induced pluripotent stem cells, to treat a form of age-related blindness.

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Read More

Budgies may be behind latest spread of H7N9 bird flu

THE humble budgie has become an unexpected menace in the latest H7N9 bird flu outbreak.

H7N9 emerged in south-east China last March, infecting 136 people. It returned in October, infecting 116 more. Nearly a third of those infected have died.

The virus cannot spread readily between people, and most cases are linked to live poultry markets. But now Jeremy Jones at St Jude Children's Research Hospital in Tennessee and colleagues in China report that budgies, finches and sparrows can contract H7N9. They can shed enough virus from their beaks into drinking water to infect other birds (Emerging Infectious Diseases, doi.org/q8d).

These species are popular pets in China, especially for older men, who have disproportionately contracted H7N9. They also figure in Buddhist ceremonies in which birds are kissed then released.

Meanwhile, another virus has emerged from the Chinese poultry industry. H10N8 killed an elderly woman last year, and now a younger woman is critically ill.

This article appeared in print under the headline "Beware the budgie"

• Subscribe to New Scientist and you'll get:


• New Scientist magazine delivered every week


• Unlimited access to all New Scientist online content -
  
  a benefit only available to subscribers


• Great savings from the normal price


• Subscribe now!

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Read More

UK government to ban e-cigarettes for under-18s

"Vaping" will soon be out for kids in the UK: plans to ban sales of electronic cigarettes to under-18s were announced last week by the government and could come into force within a year. The nation joins the 26 US states that have banned sales to minors on the basis that smoking e-cigarettes, or vaping, might tempt them to try smoking, which globally kills 6 million people each year.

"We do not yet know the harm that e-cigarettes can cause to adults, let alone to children, but they are not risk-free," said Sally Davies, the UK government's Chief Medical Officer for England. E-cigarettes dispense nicotine as a vapour, but are safer than cigarettes because they do not contain the other harmful substances found in tobacco.

But fears remain that children could become addicted to the nicotine in e-cigarettes, and that vaping could de-stigmatise smoking. "It does make sense to restrict the availability of a potentially addictive product," says Martin Dockrell, director of research and policy at anti-smoking lobby group ASH.

The UK banned sales of real cigarettes to under-18s in 2007. 12-year-olds can legally buy nicotine replacement products such as gums and patches.

Research last year showed that e-cigarettes were as effective as gums and patches at helping smokers quit or cut down. European Union regulators were last week accused by a prominent group of scientists of drafting a scientifically unjustifiable law to limit too strictly the nicotine content of e-cigarettes. In a letter, the scientists expressed their concern that smokers using e-cigarettes to quit might return to real cigarettes if they find the nicotine content of e-cigarettes to be unsatisfying.

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Read More

Ploughable sensors help farmers get more crop per drop

AT THE end of March several small bundles of electronics will be ploughed into a field in Cheshire, UK. The sensors will measure soil temperature and moisture content, then transmit those measurements wirelessly to the surface. It is the kind of information farmers around the world need to conserve water while still growing enough crops to feed an expanding population.

Currently being tested in lab soil at the University of Manchester, UK, the sensors are cheap to produce, low-power and can be left to gather information in the soil for years without maintenance. They use radio frequency identification to communicate and harvest a small amount of power from an RFID reader mounted on a tractor that collects the data as it moves over each node, says Chuan Wang, who works on the project at the university.

Another team at the University of Nebraska-Lincoln (UNL) – based in the Midwest's Corn Belt – is already well on the way to making a large-scale version of Wang's system a reality. Nebraska is the home of the iconic center pivot irrigation system responsible for the perfect circles that decorate the fields in that part of the US. They are using wireless sensors, embedded in the soil, that transmit information about current soil conditions to a base station.

By understanding exactly how much moisture is in the soil, UNL team leader Mehmet Can Vuran says entire rotations of a pivot can be saved, along with thousands of litres of water. They are already working with one of the four major center pivot irrigation companies, TL Irrigation, to bring the system to market.

"Thirty or forty per cent water savings are possible without affecting yields," Can Vuran says. "In fact, yields can be improved by optimising water – if you provide too much water to a crop it reduces the yields."

The driving force for this kind of technology is rising population, he says. It is expected to increase by 40 per cent by 2050. Demand for food will double in developing countries. "If you look at the way we're using water, we're using 70 per cent of our freshwater resources for agriculture – most of our resources, and yet the future demands that will double. As farmers say, we basically need 'more crop for drop',"

This article appeared in print under the headline "Plough in sensors to get more crop per water drop"

• New Scientist


• Not just a website!


• Subscribe to New Scientist and get:


• New Scientist magazine delivered every week


• Unlimited online access to articles from over 500 back issues


• Subscribe Now and Save

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Read More

UK government to ban e-cigarettes for under 18s

"Vaping" will soon be out for kids in the UK: plans to ban sales of electronic cigarettes to under-18s were announced last week by the government and could come into force within a year. The nation joins the 26 US states that have banned sales to minors on the basis that smoking e-cigarettes, or vaping, might tempt them to try smoking, which globally kills 6 million people each year.

"We do not yet know the harm that e-cigarettes can cause to adults, let alone to children, but they are not risk-free," said Sally Davies, the UK government's Chief Medical Officer for England. E-cigarettes dispense nicotine as a vapour, but are safer than cigarettes because they do not contain the other harmful substances found in tobacco.

But fears remain that children could become addicted to the nicotine in e-cigarettes, and that vaping could de-stigmatise smoking. "It does make sense to restrict the availability of a potentially addictive product," says Martin Dockrell, director of research and policy at anti-smoking lobby group ASH.

The UK banned sales of real cigarettes to under-18s in 2007. 12-year-olds can legally buy nicotine replacement products such as gums and patches.

Research last year showed that e-cigarettes were as effective as gums and patches at helping smokers quit or cut down. European Union regulators were last week accused by a prominent group of scientists of drafting a scientifically unjustifiable law to limit too strictly the nicotine content of e-cigarettes. In a letter, the scientists expressed their concern that smokers using e-cigarettes to quit might return to real cigarettes if they find the nicotine content of e-cigarettes to be unsatisfying.

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Read More

Peanut allergy cured in children using immunotherapy

A potentially life-threatening peanut allergy has been essentially cured in nine out of 10 recipients of a new treatment which gradually escalates the amount of peanut protein the body can tolerate.

Other treatments such as vaccines and antibodies are also under development, but the new oral immunotherapy is claimed to be the first to successfully allow people to tolerate such a food allergy.

"We've shown fantastic results, with 80 to 90 per cent of children being able to tolerate eating peanuts regularly after treatment," says Andrew Clark of Addenbrooke's Hospital in Cambridge, UK, who co-led the team that developed the treatment.

"Before the treatment, children and their parents had to check every food label, but now they can go out anywhere without fear of accidentally swallowing and reacting to traces of peanuts," he says.

Killer nut

Affecting two in every 100 children, peanut allergy kills around 50 people in the US each year – mainly through suffocating throat swellings – and results in 15,000 emergency hospital visits. "The only current 'treatments' are avoidance of peanut-containing food and shots of adrenaline to treat reactions," says co-leader of the team, Pamela Ewan, also at Addenbrooke's.

The trial, involving 99 children with peanut allergy aged between 7 and 16, is the largest ever to test an oral immunotherapy.

In the first part of the trial, 49 children received the oral immunotherapy. At their first visit to the hospital, with medical facilities standing by in case of bad reactions, the children received a tiny dose of peanut flour – around 2 milligrams – in their meal. The same amount was then added to their meals at home for two weeks. Then, every two weeks for a six-month period, the peanut flour dose was gradually boosted until it reached 800 milligrams. This is the equivalent of five whole peanuts, and 25 times the average amount of peanut that the children could tolerate beforehand.

Peanut challenge

A control group of 50 children received no therapy, and continued to avoid exposure to peanuts throughout the six-month period.

At the end of the trial period, the researchers tested all of the children's ability to safely consume gradually increasing amounts of peanut, under strict medical supervision. The researchers found that 41 of the 49 therapy recipients – 84 per cent – could handle the equivalent of five peanuts. None of the children in the control group could handle any more peanut than they could to begin with.

Next, 39 of those who could already handle five peanuts daily then faced an even sterner challenge: to try eating the equivalent of 10 peanuts, or 1400 milligrams, in one go. Twenty-four of the children, or 62 per cent, succeeded.

Finally, the 50 children in the control group underwent six months of the therapy. Of those, 91 per cent were able at the end to eat the equivalent of five peanuts a day, validating the original result in the process. "It's almost like we got two trial results for the price of one," says Ewan.

Absolutely huge

The researchers found that treatment led to a reduction in the activation of basophils, the white blood cells that trigger acute inflammation and swelling on exposure to peanut protein.

Other allergy specialists welcomed news of the therapy. "It's huge, absolutely huge," says Maureen Jenkins, director of clinical services at Allergy UK. "There hasn't been any way of treating this before."

Jenkins says that the effects of all previous attempts at treatment quickly wear off, but some children receiving the Addenbrooke's regimen have remained tolerant for five years, provided they regularly take small doses of peanut protein.

"We still need studies to see what happens if treatment stops totally, but this therapy will make a huge difference," she told New Scientist.

Don't try this at home

The research matters most for the children involved in the study. "After the trial, I felt as though a huge burden had been lifted off my shoulders," says one recipient of the treatment, 14-year-old Chris Poll of Perth, Australia. "I don't have to worry about going to parties any more, don't have to stress about going to school camps, and don't have to worry about eating in restaurants."

"A year after the trial I could eat five whole peanuts with no reaction at all," says Lena Barden, 11, from Histon in Cambridgeshire, UK. "But I still hate peanuts."

Ewan stresses that the Addenbrooke's regime should not be attempted beyond the controlled environment of a hospital until it has been developed further, such are the acute risks of peanut exposure in those with the allergy. "We must be absolutely clear to say: 'Don't try this at home'," she says.

"We're in the process of working towards being able to offer it as a specialised unit, and hope ultimately that a network of specialised units elsewhere in the UK can be set up to offer it safely," says Ewan. The team is also hoping to obtain a product license for the regime, possibly in collaboration with the pharmaceutical industry.

Journal reference: The Lancet, DOI: 10.1016/S0140-6736(13)62301-6

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Read More

Zoologger: Flying snake gets lift from UFO cross section

Video: Flying snake gets lift from UFO cross section

Zoologger is our weekly column highlighting extraordinary animals – and occasionally other organisms – from around the world

Species: Chrysopelea paradisi

Habitat: tropical rainforests of South Asia, gliding up to 100 metres from the tops of trees

Why crawl when you can fly? While their relatives slither on the ground, a few snakes take to the air, gliding from tree to tree. The most skilled of them all is the paradise tree snake, and we may finally have worked out why. It gets an aerodynamic lift by shifting its body into an unconventional, yet strangely familiar, form.

There are five species of flying snake, all native to south-east Asia. The five are reasonably average in the looks department – at least, until they begin to move. These snakes slither up trees before launching themselves from branches high in the canopy, undulating their bodies from side to side as they glide elegantly – at speeds of about 10 metres per second – to their destination.

Most studies into the snakes' gliding skills have focused on these wave-like body undulations, but Jake Socha of Virginia Tech in Blacksburg and his colleagues decided to focus on another factor.

Shape-shifter

It is clear that, once airborne, the snakes flatten their cylindrical bodies by splaying out their ribs. Slice a snake open, and the cross-sectional shape the body makes is reminiscent of a UFO from the classic Space Invaders arcade game. It's not a shape conventionally regarded as aerodynamic – but the biologists decided to investigate its properties anyway.

Socha's team recreated a 2D model of a mid-body snake slice, and then placed it in a tank filled with flowing water – a technique that allowed them to model how air would flow around it. It was much more aerodynamic than Socha expected, producing forces that, in air, would allow it to maintain near-maximum lift. "The forces are what allow it to move forward in the air and not fall down," he says.

In fact, the UFO shape outperformed more conventional aerofoil designs, like those used to construct the aircraft wings.

Scale is everything

Does that imply the aircraft industry could improve its designs? Probably not, says Socha. The trouble is, the UFO design works better than our conventional designs only for small objects gliding relatively slowly. An object about the size of a snake, in fact. Scale the design up to the size and speed of a jumbo jet, and the airflow no longer provides good lift. "If you tried to scale it up to make the wing of a passenger plane, it would be a terrible idea," says Socha.

The snakes' unusual cross-section will be a factor in their gliding ability that works with the body undulations, says Socha. His team's model suggests that the amount of lift the UFO shape provides varies depending on its orientation in the air, so the body movements may help the snake to carefully control the amount of lift while airborne.

The tip of the snake's tail, meanwhile, does not flatten out during flight and might be acting as a rudder. "One of the snakes I worked with had a naturally paralysed tail, it could glide well but it could never turn," Socha notes.

Together, these factors come together to produce a surprisingly effective little glider. Based on glide performance, Socha says their aerodynamics are pretty similar to flying squirrels.

Not bad for an animal with no limbs.

Journal reference: Journal of Experimental Biology DOI: 10.1242/jeb.090902

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Read More

Did newborn sun have weirdly weak solar wind?

OUR young sun may have been a late bloomer. The first reading of charged particles streaming from a younger solar twin shows that this constant particle flow, or wind, is rather wimpy. If our baby sun behaved like this, its timidity perhaps bought time for early Mars to play host to water.

Other young, sun-like stars are much more active than our middle-aged sun, blasting out more flares and high-energy radiation. For our sun, an increase in activity is often linked to a stronger wind, so astronomers suspected that these highly active stars would have very strong winds, and that our sun had a stormier youth too. That's why the latest find was a shock.

"Winds are hard to detect directly," says Brian Wood at the US Naval Research Laboratory in Washington DC. Instead, his team looked for the effect of stellar winds colliding with surrounding gas. That creates an ultraviolet glow which intensifies as winds get stronger (Astrophysical Journal Letters, doi.org/q33).

Using the Hubble Space Telescope, the team checked out a star that is almost exactly like our 5-billion-year-old sun but is just 500 million years old. The star shows lots of flares and other activity – but its wind is about half as strong as the sun's is today.

Other look-a-likes, about a billion years old, have much stronger winds, with around 10 times the oomph of the modern sun's output. This suggests a scenario where the stars start sleepy, ramp up and then settle back down by middle age.

If the young sun was sluggish, it might have given early Mars the time it needed for water, and perhaps life, to take hold. Evidence from NASA's rovers strongly supports the notion that the cold, dry Red Planet was once warm enough for rivers and oceans.

If so, it probably had a thicker atmosphere that vanished, perhaps stripped away by a strengthening solar wind, says Wood. NASA's MAVEN spacecraft is en route to Mars to study when and how the atmosphere was lost, including the possible influence of the sun.

This article appeared in print under the headline "Newborn sun's weak winds a boon to Mars?"

• New Scientist


• Not just a website!


• Subscribe to New Scientist and get:


• New Scientist magazine delivered every week


• Unlimited online access to articles from over 500 back issues


• Subscribe Now and Save

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Read More

More harm than good? Antioxidants defend cancer in body

They may be marketed as a way to protect yourself against disease, but antioxidant supplements are increasingly thought of as more foe than friend. We now have an idea why: antioxidants may protect healthy cells from DNA damage but they also protect cancer cells from our bodies' defences.

Antioxidants are chemicals such as beta-carotene and vitamins C and E, which mop up destructive free radicals produced when our cells metabolise energy. The new finding could help explain why some research, particularly in smokers, has shown that antioxidants end up raising rather than reducing the risk of getting cancer.

For example, in a prostate cancer prevention trial in 2011, men who took vitamin E for 5.5 years had a 17 per cent greater risk of developing the disease than men who took a placebo.

Now, research in mice has yielded a plausible explanation, at least for lung cancer. It seems antioxidants help early tumours survive and grow by protecting them and their DNA from damage from free radicals.

They do this by deactivating a gene called p53, dubbed the guardian of the genome, whose job is to destroy cells with defective DNA, including cancer cells. "Basically, the antioxidants shut off p53," which means the cancer cells can keep growing, says team leader Martin Bergö at the University of Gothenburg in Sweden.

To work out what was going on, Bergö and his colleagues triggered small lung cancers in mice and then gave some of them antioxidants. Of those receiving treatment, half got vitamin E and the other half an antioxidant called N-acetyl cysteine (NAC), a drug given to reduce mucus levels in people with chronic obstructive pulmonary disease (COPD).

Total knock-out

The results were dramatic. "The tumour number, size and aggressiveness increased threefold in the mice receiving either antioxidant, compared with non-recipients," says Bergö. "Also, survival was cut by at least 50 per cent."

Further experiments on colonies of tumour cells from humans and mice showed that they grew faster after exposure to the antioxidants. Moreover, the activity of p53 fell dramatically, suggesting that the antioxidants switched off the gene's ability to sense and destroy defective cells. The effect of antioxidants on tumour growth was the same as knocking out p53 altogether, Bergö found.

Bergö says the results only suggest risks for people who already have small lung tumours, or are at risk of them. "Our study doesn't say anything about the use of antioxidants in healthy people, and their risk of cancer in the future," he says. "But if you have lung cancer, or increased risk of lung cancer because you smoke or you have COPD, our results suggest antioxidants would fuel the growth of any tumours, so use them with caution, or not at all."

Balanced diet

Concerns have also been raised that antioxidants may interfere with cancer treatments, says Emma Smith, a spokesperson for Cancer Research UK. "We recommend that people stick to a healthy balanced diet, which should provide all the nutrients needed without taking supplements," she says.

Shyam Biswal of Johns Hopkins Bloomberg School of Public Health in Baltimore says the next step will be to see if NAC and other antioxidants promote tumours in mice at high risk of cancer having been exposed to a carcinogen, as well as those bred to have the disease. "It also warrants more study in patients with COPD," he says.

Bergö plans to perform some of this follow-up work, as well as investigating the effects of antioxidants on other cancers, including malignant melanomas and gut cancers.

Journal reference: Science Translational Medicine, DOI: 10.1126/scitranslmed.3007653

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Read More

Why you should care about the end of net neutrality

Companies can now pay for their pages to be delivered faster in the US. Does this mean the end of the internet as we know it?

IS THIS the end of the internet as we know it? On 14 January, the guiding principle of internet freedom, known as net neutrality, was demolished in a US appeals court in Washington DC. Pro-neutrality activists say it is the harbinger of dark times for our connected world. Information will no longer be free, but governed by the whims of big business. Internet Service Providers (ISPs) like Verizon and AT&T argue that since they built the physical backbone of the net they should be able to charge people to use it.

Lost amid the rancour is any hint of what this might mean for the average user – but there are several possibilities. The court ruling found that the US Federal Communications Commission (FCC) cannot regulate ISPs to prevent them from charging for different connection speeds. That means they are now free to demand users – whether they are big companies like Google or Netflix, or individuals – pay a premium for fast delivery of web pages, video and other content. Those who opt for cheaper schemes could see their traffic capped at slower speeds, or interrupted to make way for the big spenders.

If companies and ISPs can come to an agreement, though, things aren't likely to be quite as bleak, and the new landscape might look more like existing television subscription packages. Just as you can shell out for premium channels like HBO and Sky Movies, ISPs could offer internet packages that include Netflix and Hulu. In such a set-up, users only pay for what they want – like news channels or gaming sites – but not for the rest.

The early indications are, however, that the net-based firms who rely on ISPs the most are far from happy. Netflix, whose streaming video service accounts for more than a quarter of all internet traffic, is likely to be a prime target for ISPs planning to capitalise on the ruling. In reaction to the court's decision, Reed Hastings, the company's CEO, promised to vigorously protest any draconian discrimination from ISPs.

If such conflicts aren't resolved, things could get ugly. "Tweets, emails and texts will be mysteriously delayed or dropped. Videos will load slowly, if at all. Websites will work fine one minute, and time out another," said media advocacy group the Free Press in a statement after the verdict. "Your ISP will claim it's not their fault, and you'll have no idea who is to blame."

But the FCC could still intervene to keep net neutrality. The agency could designate ISPs as "common carriers", a label that would enable them to treat ISPs like phone companies, which are highly regulated. If the FCC doesn't act, activists worry about what it will mean for the little guys.

"The internet was supposed to be this great equaliser. It didn't matter where you lived or how wealthy you were," says Bartees Cox at Public Knowledge, a digital rights advocacy group. Without net neutrality, the poor and underprivileged are particularly at risk of losing out. If the internet is only available in high-priced bundles, then people will be restricted to what they can afford, he says.

Cox says the scales will also be tipped against internet start-ups, which won't have the capital to compete with established companies.

"It's a shame if this really goes through," he says. "The only person that wins at the end of the day is the ISPs."

This article appeared in print under the headline "Net not free for all"

• New Scientist


• Not just a website!


• Subscribe to New Scientist and get:


• New Scientist magazine delivered every week


• Unlimited online access to articles from over 500 back issues


• Subscribe Now and Save

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Read More

Beams of sound immerse you in music others can't hear

From restaurant music that only certain tables can hear to flying emails, the ability to place sound exactly where you want it has all kinds of unusual uses

IF YOU'RE sick of wading through a clogged email inbox or scrolling through endless Twitter timelines, Jörg Müller has a more fun way of sifting through your messages: sound.

In his audio-enabled "BoomRoom" at the Technical University of Berlin, Germany, emails and tweets fly around you like a flock of birds, each chirping a subtly different sound that identifies the sender. More urgent messages whizz directly over your head. Touch one and a computer reads it out.

Being able to direct sound in such a focused way has only recently become possible thanks to smarter audio processing algorithms, directional loudspeakers and gesture-recognition technology, says Müller. His flying email concept might still seem a bit far-fetched, but steering sound exactly where it is wanted is already catching on elsewhere in a number of different real-world applications. One day, it might even help create smart homes that can speak to their visually impaired owners.

For example, Parametric Sound of San Diego, California, has developed a highly directional "hypersound" loudspeaker that makes audible sound ride on an inaudible ultrasound carrier wave. This allows a gamer to be immersed in stereo audio that only they can hear – and it was a gaming highlight of January's Consumer Electronics Show in Las Vegas, Nevada.

Hypersound is also being trialled in branches of McDonald's in Disneyland and North Euclid, California. "There's often a TV on in McDonald's but not everyone wants to listen to it. So you can decide whether you want the TV sound beamed to your table," says Parametric Sound spokesman David Lowey. In toy shops, the Build-A-Bear chain is beaming instructions on how to build the toy to children using hypersound. "Car makers are looking at it too – so only the driver hears the GPS navigation instructions," Lowey says.

Back in Berlin, the BoomRoom consists of a ring of 56 loudspeakers that allow sounds to be assigned stationary or mobile positions in the space around you (see diagram). An array of 16 gesture-recognising cameras allows you to control what those sounds do. A music track, for instance, could be assigned to an object in the room such as a vase. To play the track you simply pick up the vessel and "pour out" a track in mid air. Gestures such as moving your hands apart or bringing them together can alter qualities like volume, treble and bass. "The instruments exist in mid-air so you can do your own sound mixing," says Müller, whose team is working alongside Sascha Spors of the University of Rostock, Germany.

The BoomRoom relies on a technique developed at the Delft University of Technology in the Netherlands called wave field synthesis (WFS). This constructs a 3D sound field by cancelling and reinforcing sound waves in much the same way as a hologram does with light waves. The trick is to use an algorithm that controls the speakers precisely and uses constructive and destructive interference of the sound waves to place sounds where they are wanted, moment by moment. "It's actually easier to produce a 3D sound field than it is with light because audio frequencies are so much lower," says Spors.

Timing so many loudspeakers at once is crucial and it has only just become possible because the computer power needed to run the algorithms has finally been developed, says Müller. The speakers aren't special in any way: all the WFS algorithms need to know is where each speaker is. "All the magic happens in software," says Müller. The system will be presented at the annual computer human interaction conference in Toronto, Canada, in April.

For Müller, the standout application of this technology is as a future smart room for people who are blind or sight-impaired. If a blind person entered a room, the important objects inside could announce their location. Users could also leave messages for one another in mid-air to be read out by a computer.

Another aim is to assign sounds to items in a room to reduce the number of gadgets we need. A bowl of marbles, for instance, could become an answering machine: the bowl could click when there are messages in it – and the user picks up a marble to hear a message. When they have heard it, pretending to pluck it out of the marble deletes the message.

To work in everyday life, the hope is that the flat panel actuators that act as loudspeakers by making glass and other flat surfaces vibrate will drop in price in coming years, making it cheap enough to fill houses with them. "We believe that in the future loudspeaker panels will be integrated in walls," says Müller.

The technology could also be a boon to gamers. The BoomRoom was first used for an audio-based lightsaber game in which a blindfolded person had to react to the "zummm, zummm" of a digital adversary's lightsaber, their voice or their breath on the back of their neck. It worked too well: "They found it impressively immersive and fun to use. But some hit out quite frantically and we had to calm them down to stop them hitting the speakers," says Müller.

Sound sculptor Bill Fontana of San Francisco, California – who once turned London's Millennium Bridge into a "live musical instrument" playing in the hall of the nearby Tate Modern – describes the Berlin technology as having fantastic potential to push sound in novel directions. "There is a lot of uncharted territory with using sound in our living and architectural spaces. Culturally, we are acoustically illiterate in many ways and regard most sound as noise."

This article appeared in print under the headline "Pure sound, direct to you"

• New Scientist


• Not just a website!


• Subscribe to New Scientist and get:


• New Scientist magazine delivered every week


• Unlimited online access to articles from over 500 back issues


• Subscribe Now and Save

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Read More

Cyclones hitting Australia plummet to 1500-year low

Off the chart: cyclone activity in Australia has been lower over the last 40 years than at any time in the past 1500 years. But the seemingly good news comes with a sting in the tail for people living on the coast.

Radar and satellite records of tropical cyclones – rotating storm systems – stretch back only about four decades. For an idea of trends on the longer term, researchers must go underground.

Compared with typical monsoonal rains, the severe rains associated with tropical cyclones are unusually low in the heavier oxygen isotope – oxygen-18. Stalagmites forming in caves record this difference, so by analysing their growth bands – which form each year in the wet season – geologists can establish whether or not a given year was characterised by cyclone activity.

The future, today

Jordahna Haig and Jonathan Nott of James Cook University in Cairns, Queensland, Australia, and their colleagues examined stalagmites from the coast of Queensland and Western Australia. Their results show that cyclone activity in Australia since 1900 has been dramatically lower than at any time since about AD 500. There was an even steeper drop from about 1960, corresponding closely with the sharp increase in global temperatures.

Climate models predict that cyclone frequency will decrease – and individual cyclones will become more intense – as the world warms. However, these effects were only expected to be significant by about 2050. "Models are saying this is going to occur later on. What we're saying is that we're seeing this now," says Nott.

Nott says anthropogenic climate change cannot be ruled out as a factor in the cyclone activity trend, although the link will be difficult to prove. But he notes that a cyclone record going back 1500 years provides an opportunity for long-term comparisons with records of other things that might affect cyclone activity, like solar minima and El Niño. It seems that these have not caused such a change in cyclone activity in the past.

Grossly underestimated risk

If cyclones are to become less frequent but more intense, that is bad news for people living on Australia's coast. It suggests they may have to deal with stronger cyclone-induced storm surges and flooding in future. "We've grossly underestimated the risks with building close to sea level," says Nott.

Scott Power from the Bureau of Meteorology in Canberra, Australia, says the issue is particularly important today because there are more people living along Australia's coast than ever before.

Whether a drop in cyclone activity around Australia means an increase in other regions of the planet is not clear, says Kevin Walsh at the University of Melbourne, Australia. For that, similar studies would need to be done elsewhere.

Nott and his colleagues are already on the case. They are now analysing geological records from Madagascar, to the Cook Islands and Vanuatu. "We're working on the whole southern hemisphere," he says.

Journal reference: Nature, DOI: 10.1038/nature12882

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Read More