Spyware that can identify what films you are watching

We know what you’re doing

REMEMBER that racy film you probably should not have enjoyed on Netflix last weekend? Eran Tromer’s algorithms can tell what it was. Although videos streamed from services such as Netflix, Amazon and YouTube are encrypted in various ways to ensure privacy, all have one thing in common: they leak information. Dr Tromer, of Tel Aviv university, his colleague Roei Schuster and Vitaly Shmatikov of Cornell have worked out how those leaks can identify the film you are watching—even if they cannot directly observe the stream of bits delivering it, or obtain access to the device on which you are watching it.

Videos streamed over the internet are usually transmitted using a standard called MPEG-DASH. This chops a data stream up into segments that are then encrypted and fetched one at a time by the machine playing the video. The result is an on-off, “bursty” pattern of data arrival. But not all segments are equal. One depicting the mating habits of sloths will contain less information than another showing a car chase. Streaming services use something called variable bit-rate (VBR) compression to take advantage of this….Continue reading
Source: Economist

How to build an artificial womb

Sheep may safely laze

THESE days, in rich countries, premature birth is the main cause of infant mortality. A baby born at 23 weeks—just over half way through a normal pregnancy—has a fighting chance of survival. But underdeveloped lungs struggle to cope with breathing air. External pumps used to circulate blood impose potentially fatal stresses on tiny hearts. Those that do pull through are often left with lifelong problems that range from brain damage to blindness. In a paper just published in Nature Communications, a team of doctors at the Children’s Hospital of Philadelphia, led by Alan Flake, describe an artificial womb that, they hope, could improve things dramatically, boosting the survival rate of the most premature babies while reducing the chance of lasting disabilities.

The device, which looks a bit like a high-tech jiffy bag, is designed to mimic a real womb as closely as possible (see picture above, of a fetus after 28 days in the artificial womb). The fetus—a lamb in the team’s trials—is surrounded in a substitute for the amniotic fluid that keeps the animal’s lungs filled with liquid in a real uterus….Continue reading
Source: Economist

The first humans in America may not have been Homo sapiens

WHEN did the first human beings arrive in the Americas? Though there are arguments about the details, the consensus is that it was around 15,000 years ago, when retreating glaciers at the end of the last ice age permitted travellers from Asia to cross what is now the Bering strait but was then dry land.

This makes sense. The evidence suggests that, recent migrants from Africa and their progeny aside, people now alive in Asia, Australia, Europe and the Americas are descended from a handful of Africans who left the continent of their birth about 70,000 years ago. This fits nicely with the conventional date for America’s colonisation, by giving time for the heirs of these African émigrés to make it to eastern Asia, ready for the hop to the New World when conditions permitted.

What, then, to make of a discovery, reported in this week’s Nature, by Thomas Deméré of the San Diego Natural History Museum and his colleagues? They have just dated an archaeological site found in California in 1992, which seems to be a place where human beings used stone tools to dismember a mastodon, a now-extinct type of elephant. Unfortunately for existing theories, the…Continue reading
Source: Economist

Plastic-eating caterpillars could save the planet

MOST scientific research follows a logical progression, with one experiment following up on the findings of another. Every now and then, however, serendipity plays a part. Such is the case with a paper just published in Current Biology, which reveals to the world a moth that is capable of chewing up plastic.

The experiment behind the paper was inspired when Federica Bertocchini, an amateur beekeeper who is also a biologist at Cantabria University, in Spain, was looking at some of the honeycombs in her hives and noticed caterpillars chewing holes through the beeswax and lapping up the honey. Such pests are not uncommon, so to be certain of what she was dealing with, she collected some of the caterpillars and took them home in a plastic shopping bag for subsequent examination. She assumed the larvae would be unable to escape from this bag, but she was wrong. When, a few hours later, she got around to looking at her captives she found the bag pierced by holes and the caterpillars roaming around her house.

After rounding them up, she identified them as the larvae of the greater wax moth, a well-known pest of bee hives. On considering their escape from their…Continue reading
Source: Economist

Makeover for mobile phones

AFTER years of hot air and hyperbole, the fifth generation (5G) of mobile-phone technology has entered its final phase of testing, in preparation for its debut around the world. The Third Generation Partnership Project (3GPP), an industry group for mobile phones, has still to sign off on a 5G reference design that satisfies all its members. But that has not stopped manufacturers from introducing 5G chip-sets and modems for wireless carriers to test. The hope is to get 5G mobile networks up and running in time, at least, for the winter Olympics in South Korea in February 2018. Japan has its own plans for the technology when it hosts the summer Olympics in July 2020. Expect wireless carriers to start rolling out their 5G networks in earnest shortly thereafter.

The race to launch 5G is reminiscent of the rush to do likewise with Wi-Fi in the 1990s, when equipment makers hurried out interim gear both in order to influence emerging standards (and thus lock in their own particular patents) and to get a foot in the door ready for when the technology took off. Which it duly did. Many believe 5G could be an even bigger change. Hype aside, the technology is more than just a faster,…Continue reading
Source: Economist

Imitating people’s speech patterns precisely could bring trouble

UTTER 160 or so French or English phrases into a phone app developed by CandyVoice, a new Parisian company, and the app’s software will reassemble tiny slices of those sounds to enunciate, in a plausible simulacrum of your own dulcet tones, whatever typed words it is subsequently fed. In effect, the app has cloned your voice. The result still sounds a little synthetic but CandyVoice’s boss, Jean-Luc Crébouw, reckons advances in the firm’s algorithms will render it increasingly natural. Similar software for English and four widely spoken Indian languages, developed under the name of Festvox, by Carnegie Mellon University’s Language Technologies Institute, is also available. And Baidu, a Chinese internet giant, says it has software that needs only 50 sentences to simulate a person’s voice.

Until recently, voice cloning—or voice banking, as it was then known—was a bespoke industry which served those at risk of losing the power of speech to cancer or surgery. Creating a synthetic copy of a voice was a lengthy and pricey process. It meant recording many phrases, each spoken many times, with different emotional emphases and in different contexts (statement, question,…Continue reading
Source: Economist

Using fluorescent bacteria to find landmines

BATTLEFIELDS strewn with mines are one of the nastiest legacies of war. They ensure that, long after a conflict has ceased, people continue to be killed and maimed by its aftermath. In 1999, the year the Ottawa Mine Ban Treaty came into force, there were more than 9,000 such casualties, most of them civilians. Though this number had fallen below 4,000 by 2014 it is, according to the Landmine and Cluster Munition Monitor, an international research group, rising again as a consequence of conflicts in Libya, Syria, Ukraine and Yemen.

These days most mines have cases made from plastic. Only the firing mechanisms include any metal. That means mines are hard to find with metal detectors. Many ingenious ways to locate and destroy them have been developed, ranging from armour-plated machines that flail the land, via robots equipped with ground-penetrating radar, to specially trained rats that can smell the explosives a mine contains. Such methods have, though, met with mixed success—and can also be expensive. Flails, for instance, scatter shrapnel and explosive residue around a minefield, making it hard to confirm that no undetonated devices remain. Minehunting rats, meanwhile,…Continue reading
Source: Economist

Having secrets is not a problem. Thinking about them is

KEEPING a secret is hard work, as both common sense and past studies confirm. Omitting pertinent information from a conversation, or even intentionally misleading an interlocutor, requires nimble thinking. How much of a burden, though, is merely possessing a secret, rather than trying to defend it against a nosy questioner? The catharsis that often accompanies confessing guilty secrets suggests it may be quite large. But, until now, no one has examined the matter scientifically.

In a study just published in the Journal of Personality and Social Psychology, Michael Slepian of Columbia University, in New York, attempts to correct that omission. He and his colleagues presented a set of volunteers with a list of 38 sorts of things surveys suggest people commonly keep secret about themselves. Examples included infidelity, theft, poor performance at work, sexual orientation, having undergone an abortion and drug taking. Some of Dr Slepian’s volunteers participated over the internet. Some, recruited in New York’s biggest public space, Central Park, participated face to face. All remained anonymous—and, within statistical limits, both groups responded…Continue reading
Source: Economist

Crayfish may help researchers understand drunkenness

I’m not as thunk as drinkle peep I am

HUMANS are not the only species to enjoy a snifter. Myriad experiments on other animals, from rats and monkeys to bees and fruit flies, show that they also get drunk, will seek out alcohol given the opportunity and may even develop a dependence on the stuff. But alcohol promotes conviviality as well as drunkenness, and that relationship is less well explored. In particular, there are few studies of whether the link is reciprocal—whether conviviality, or at least a sociable environment, affects susceptibility to alcohol. This question has, however, now been looked into. In a paper just published in Experimental Biology, Matthew Swierzbinski, Andrew Lazarchik and Jens Herberholz of the University of Maryland have shown that a sociable upbringing does indeed increase sensitivity to alcohol. At least, it does if you are a crayfish.

The three researchers’ purpose in studying drunken crayfish is to understand better how alcohol induces behavioural changes. Most recreational drugs, from cocaine and heroin to nicotine and caffeine, have well-understood effects on known receptor…Continue reading
Source: Economist

Penicillin changes the behaviour of young mice

THE symbiosis between human beings and the bacteria dwelling in their guts is a delicate thing. When it works well, both sides benefit. The bugs get a comfy home. The hosts get help with their digestion, making more food available than otherwise would be. If relations are upset, though, bad consequences may flow. Both obesity and malnutrition can be exacerbated by the wrong gut bacteria. Illnesses such as asthma and eczema are linked to a lack of certain bugs from an infant’s intestines. And there is evidence, from experiments on mice, that an absence of gut flora affects the development of the brain. Such absence weakens the blood-brain barrier, which normally helps to keep foreign material out of that organ. It also seems to make animals less sociable than would otherwise be expected.

The experiments which show these brain and behavioural changes have, though, either been done on mice raised in sterile conditions or on ones that have had their alimentary bacterial ecosystems “nuked” with antibiotics in high dose—far higher, pro rata, than would be administered to a human for medical reasons. The next stage is to test whether anything similar happens to mice fed…Continue reading
Source: Economist