WASHINGTON — A quantum internet could one day allow ultrasecure communications worldwide — but first, scientists must learn to tame unruly quantum particles such as electrons and photons. Several new developments in quantum technology, discussed at a recent meeting, have brought scientists closer to such mastery. Scientists are now teleporting particles’ properties across cities, satellite experiments are gearing up for quantum communications in space, and other scientists are developing ways to hold quantum information in memory.

In one feat, scientists achieved quantum teleportation across long distances through metropolitan areas. Quantum teleportation transfers quantum properties of one particle to another instantaneously. (It doesn’t allow for faster-than-light communication, though, because additional information has to be sent through standard channels.)
Using a quantum network in Calgary, scientists teleported quantum states of photons over 6.2 kilometers. “It’s one step towards … achieving a global quantum network,” says Raju Valivarthi of the University of Calgary in Canada, who presented the result at the International Conference on Quantum Cryptography, QCrypt, on September 12.

A second group of scientists recently teleported photons using a quantum network spread through the city of Hefei, China. The two teams published their results online September 19 in Nature Photonics.

The weird properties of quantum particles make quantum communication possible: They can be in two places at once, or can have their properties linked through quantum entanglement. Tweak one particle in an entangled pair, and you can immediately seem to affect the other — what Albert Einstein called “spooky action at a distance.” Using quantum entanglement, people can securely exchange quantum keys — codes which can be used to encrypt top-secret messages. (SN: 11/20/10, p. 22). Any eavesdropper spying on the quantum key exchange would be detected, and the keys could be thrown out.

In practice, quantum particles can travel only so far. As photons are sent back and forth through optical fibers, many are lost along the way. But certain techniques can be used to expand their range. Quantum teleportation systems could be used to create quantum repeaters, which could be chained together to extend networks farther. But in order to function, quantum repeaters would also require a quantum memory to store entanglement until all the links in the chain are ready, says Ronald Hanson of Delft University of Technology in the Netherlands. Using a system based on quantum entanglement of electrons in diamond chips, Hanson’s team has developed a quantum memory by transferring the entanglement of the electrons to atomic nuclei for safekeeping, he reported at QCrypt on September 15.

Satellites could likewise allow quantum communication from afar. In August, China launched a satellite to test quantum communication from space; other groups are also studying techniques for sending delicate quantum information to space and back again (SN Online: 6/5/16), beaming up photons through free space instead of through optical fibers. “A free-space link is essential if you want to go to real long distance,” Giuseppe Vallone of the University of Padua in Italy said in a session at QCrypt on September 14. Particles can travel farther when sent via quantum satellite — due to the emptiness of space, fewer photons are absorbed or scattered away.
Quantum networks could also benefit from processes that allow the use of scaled-down “quantum fingerprints” of data, to compare files without sending excess data, Feihu Xu of MIT reported at QCrypt on September 12. To check if two files are identical — for example, in order to find illegally pirated movies — one might compare all the bits in each file. But in fact, a subset of the bits — or a fingerprint — can do the job well. By harnessing the power of quantum mechanics, Xu and colleagues were able to compare messages using less information than classical methods require.

The quantum internet relies on the principles of quantum mechanics, which modern-day physicists generally accept — spooky action and all. In 2015, scientists finally confirmed that a key example of quantum weirdness is real, with a souped-up version of a test known as a Bell test, which closed loopholes that had weakened earlier Bell tests (SN: 9/19/15, p. 12). Loophole-free Bell tests were necessary to squelch any lingering doubts, but no one expected any surprises, says Charles Bennett of the IBM Thomas J. Watson Research Center in Yorktown Heights, N.Y. “In a certain sense it’s beating a dead horse.”

But Bell tests have applications for the quantum internet as well — they are a foundation of an even more secure type of quantum communication, called device-independent quantum key distribution. Typically, secure exchanges of quantum keys require that the devices used are trustworthy, but device-independent methods do away with this requirement. This is “the most safe way of quantum communication,” says Hanson. “It does not make any assumptions about the internal workings of the device.”

Motors too small to see with the eye may soon have the power to drive innovations in chemistry, biology and computing. Three creators of such nanoscopic machines were honored October 5 with the Nobel Prize in chemistry.

Sharing the prize of 8 million Swedish kronor (about $930,000) equally are Jean-Pierre Sauvage, J. Fraser Stoddart and Bernard Feringa. “If you had to choose three people at the top of the field, that’s it. These are the men,” says James Tour, a na
Recognition of the burgeoning field of molecular motors will draw more money and inspire children to become scientists, says Donna Nelson, an organic chemist at the University of Oklahoma in Norman and the president of the American Chemical Society. “It will benefit not only these three chemists, it will benefit the entire field of chemistry.”
Chemists and physicists have envisioned molecular machines since at least the 1960s, but were never able to reliably produce complex structures. Then in 1983, Sauvage, of the University of Strasbourg in France, devised a method for making interlocking molecular rings, or catenanes. Sauvage’s molecular chain set the stage for the rest of the field (SN: 9/8/90, p. 149).

Stoddart, of Northwestern University in Evanston, Ill., improved the efficiency so that he could produce large quantities of molecular machines, starting in 1991 with rings clipped around a central axle. That structure is known as a rotaxane. He and colleagues learned to control the slide of the rings along the axle, making a simple molecular switch. Such switches could be used to create molecular computers or drug delivery systems. Stoddart showed in 2000 that it was possible to make molecular “muscles” using interlocking rings and axles. Stoddart and colleagues have since devised molecular elevators and pumps based on the same molecules.
Feringa, of the University of Groningen in the Netherlands, ramped things up another notch in 1999 by building the first molecular motor. Things move so differently at the molecular scale that many researchers weren’t sure anyone could precisely control the motion of molecular motors, says R. Dean Astumian of the University of Maine in Orono. Feringa’s innovation was to devise asymmetric molecules that would spin in one direction when hit with a pulse of light.

Up to 50,000 of the motors could span the width of a human hair, says Tour. Alone, one of the spinning motors doesn’t pack much punch (SN: 2/7/04, p. 94), but harnessed together in large numbers the little motors can do big work, he says. Groups of the whirring motors powered by light can rotate a glass rod thousands of times their size and do other work on a macroscopic scale. Feringa also harnessed his motors into a four-wheel-drive “nanocar” (SN: 12/17/11, p. 8).

The process of making molecular machines has improved drastically over recent decades, thanks in large part to the work of the three newly christened laureates, says Rigoberto Advincula, a chemist at Case Western Reserve University in Cleveland. Scientists have a better understanding of how to construct molecules that more reliably bend, loop and connect to form shapes. “You don’t have tweezers to put them together,” he says. “You template the reaction so that the thread to goes through the ring. That then makes it easier for the two thread ends to meet each other.” New techniques have also allowed the production of more intricate shapes. Further development will bring these processes to even bigger scales, allowing for the design of molecular machines for everything from energy harvesting to building protein complexes, Advincula says.
Such applications are still on the horizon and no one really knows what sorts of machines chemists can make from molecules yet. When people question Feringa about what his molecular motors can be used for, he “feels a bit like the Wright brothers” when people asked them after their first flight why they needed a flying machine, he said during a telephone call during the announcement of the prize. There are “endless opportunities,” including nanomachines that can seek and destroy tumor cells or deliver drugs to just the cells that need them, Feringa speculated.

Stoddart, who was born in Edinburgh and moved to the United States in 1997, applauded the Nobel committee for recognizing “a piece of chemistry that is extremely fundamental in its making and being.” Sauvage, in particular, created a new type of molecular bond in order to forge his chain, Stoddart said during a news conference. “New chemical compounds are probably several thousand a day worldwide,” he said. “New chemical reactions, well, maybe a dozen or two a month. Maybe I go over the top there. But new bonds, they are few and far between. They are really the blue moons. So I think that’s what’s being recognized, more than anything.”

With virtual reality finally hitting the consumer market this year, VR headsets are bound to make their way onto a lot of holiday shopping lists. But new research suggests these gifts could also give some of their recipients motion sickness — especially if they’re women.

In a test of people playing one virtual reality game using an Oculus Rift headset, more than half felt sick within 15 minutes, a team of scientists at the University of Minnesota in Minneapolis reports online December 3 in Experimental Brain Research. Among women, nearly four out of five felt sick.
So-called VR sickness, also known as simulator sickness or cybersickness, has been recognized since the 1980s, when the U.S. military noticed that flight simulators were nauseating its pilots. In recent years, anecdotal reports began trickling in about the new generation of head-mounted virtual reality displays making people sick. Now, with VR making its way into people’s homes, there’s a steady stream of claims of VR sickness.

“It’s a high rate of people that you put in [VR headsets] that are going to experience some level of symptoms,” says Eric Muth, an experimental psychologist at Clemson University in South Carolina with expertise in motion sickness. “It’s going to mute the ‘Wheee!’ factor.”

Oculus, which Facebook bought for $2 billion in 2014, released its Rift headset in March. The company declined to comment on the new research but says it has made progress in making the virtual reality experience comfortable for most people, and that developers are getting better at creating VR content. All approved games and apps get a comfort rating based on things like the type of movements involved, and Oculus recommends starting slow and taking breaks. But still some users report getting sick.

The new study confirms these reports. A team led by Thomas Stoffregen, a kinesiologist who has been studying motion sickness for decades, tested the susceptibility of two sets of 18 male and 18 female undergraduates during two different VR games using an Oculus Rift DK2 headset. The first game, which involved using head motions to roll a virtual marble through a maze, made 22 percent of the players feel sick within the 15 minutes they were asked to play.

Another 36 students played the horror game Affected, using a hand-held controller to navigate a creepy building. This time, 56 percent felt sick within 15 minutes. Fourteen of 18 women, nearly 78 percent, were affected, compared with just over 33 percent of men. Though the study tested only an Oculus Rift, other companies’ VR headsets based on similar technology may have similar issues.
This gender difference shows up in almost any situation that can cause motion sickness, like a moving car or a rocking boat. But Stoffregen says the disparity can’t be explained by the most widely accepted theory of motion sickness, which suggests that it’s caused by a mismatch between the motion your body is sensing and what your eyes are seeing, like when you read in a moving car. With VR, the theory goes, your eyes think you’re moving, but your body feels stationary, and this makes you feel sick.

Stoffregen thinks motion sickness is instead caused by things that disrupt your balance, like a boat pitching over a wave. And if you try to stabilize your body in the virtual world you see — say, by leaning into a virtual turn — instead of in the physical world you’re in, you can lose stability.

Men and women are typically different shapes and sizes, so they differ in the subtle, subconscious movements that keep their bodies balanced, known as postural sway, Stoffregen says. This difference makes women more susceptible to motion sickness, he claims. For the new study, he measured participants’ balancing motions before they played the games and found a measurable difference in sway between those who reported feeling sick and those who didn’t.

Because motion sickness is a complicated set of symptoms, self-reporting by participants may not be a reliable way to measure it, Muth argues. And, he says, “I would say the science isn’t there yet to draw that conclusion” about gender bias, adding he’d like to see the result replicated with a larger group.

Even so, with VR potentially poised to jump from the gaming world into more mainstream aspects of society — Facebook CEO Mark Zuckerberg says he wants “a billion people on Facebook in virtual reality as soon as possible” — a gender disparity could become a real problem, especially if VR enters the workplace, Stoffregen says. “If it were only games, it wouldn’t matter, and nobody would care.”

Babies are little heartbreakers — literally. Genetic variants linked to fertility are also linked to coronary artery disease, a new study finds.

It’s not uncommon to find genes that affect more than one trait, but this is the first time scientists have seen a genetic connection between reproduction and heart disease, the researchers report online June 22 in PLOS Genetics. “Evolution is on a buy now, pay later plan,” says coauthor Stephen Stearns, an evolutionary biologist at Yale University. The connection “leads to a view of us as a bundle of trade-offs,” he says. And in this case, genes’ reproductive benefits apparently outweigh even lethal side effects later in life.
Coronary artery disease — one of the most deadly diseases worldwide — results from plaque accumulation in the arteries that supply blood to the heart. That type of buildup, which can start in young adulthood, has afflicted humans for millennia, and scientists have wondered why the genetic variants complicit in the disease haven’t yet been weeded out of the gene pool.

“There must be some advantage to these genes that makes them worth keeping,” says Shari Grossman, a geneticist at the Broad Institute in Cambridge, Mass., who was not involved in the study.

Researchers examined genetic variants associated with coronary artery disease and found evidence that they spread rapidly through the human population within the last 10,000 years or so. This implies that sometime in relatively recent human history these tweaked genes provided an evolutionary advantage.

Then the researchers reviewed 143 previous studies and discovered many of these same genes were linked to — and probably enhanced — important reproductive functions, such as male and female fertility as well as fetal development and survival. This suggests that the genetic quirks associated with coronary artery disease persisted because the people who had them bore more children.

Having birthrate-boosting genes was probably particularly advantageous in the last several thousand years because of the transition to agriculture, Stearns says. Agriculture led to people settling down and eventually moving to cities, where rampant infectious diseases hiked mortality rates, especially among children. People with these genetic variants would have been more likely to continue their lineage, even if they were predisposed to suffer heart problems later on.
This study may be a warning for gene therapy, since it suggests there are many genetic connections between different bodily functions that scientists don’t yet understand, Stearns says. If doctors want to treat coronary artery disease by editing a person’s DNA, it’s important to know what other traits might be affected.

The new findings also raise questions about the various functions of other disease-related genes, says Hamdi Mbarek, a molecular geneticist at Vrije University Amsterdam who was not involved in the work. For instance, a future study could examine whether genes associated with cancer have any hidden evolutionary benefits.

A bad bacterium may make colon cancer worse.

Streptococcus gallolyticus spurred growth of some colon cancer cells in lab dishes and in mice, researchers report July 13 in PLOS Pathogens. S. gallolyticus stimulates a biochemical chain reaction that scientists already knew is involved in the development of colon cancer, the researchers discovered.

Bacteria had to be in direct contact with tumor cells to speed growth, but exactly how the bacteria do that isn’t yet known. Further investigation could help researchers find ways to block the microbe’s action, leading to better treatments for colorectal cancer, says microbiologist Yi Xu of Texas A&M University Health Science Center in Houston.
People who have heart valve or blood infections of S. gallolyticus (previously known as S. bovis) often also have colorectal tumors. The bacterium has also been found growing on tumors in some colorectal cancer patients. But doctors couldn’t tell from association studies whether the bacteria were egging on tumors or were innocent bystanders.

Xu and colleagues grew S. gallolyticus in lab dishes with several different types of human cells. Three types of colon cancer cells grew faster, producing about 50 to 60 percent more cells within 24 hours, with the bacteria than they did when cultured with no bacteria or with a harmless, milk-fermenting bacterium called Lactococcus lactis. Normal human colon cells, kidney cells, lung cancer cells and two strains of colon cancer cells didn’t respond to the bacteria. Those results could mean that the bacterium doesn’t spur on all colon cancers, says Cynthia Sears, an infectious disease specialist at Johns Hopkins University School of Medicine who was not involved in the work. Finding out what makes some cells more vulnerable to the bacteria will be important for future studies, she says.

“It deserves a deeper look,” Sears says.

Colon cancer‒prone mice infected with S. gallolyticus had more and bigger tumors than those found in mice inoculated with L. lactis or with a saline solution.

Xu and colleagues don’t know all the details of how S. gallolyticus promotes colon cancer growth. But the researchers discovered that when the bacteria glom onto responsive colon cancer cells, the microbes boost a signal sent through a relay chain known as the beta-catenin pathway. That pathway was already known to be involved in generating colorectal tumors. The researchers have some evidence that S. gallolyticus may also work through other chemical signaling pathways to enhance colon cancer growth.
Whether the bacterium can initiate colon cancer isn’t clear, Xu says.

Researchers will also need to investigate how S. gallolyticus works with or against other microbes that live in the colon, says Ran Blekhman, a geneticist at the University of Minnesota in Minneapolis. The study is part of a growing trend away from merely associational studies toward discovering how microbes function in the body, he says. “This is basically the next step in microbiome research.”

Made out of a mere five molecules, the Ohio Bobcat Nanowagon checks in at 3.5 nanometers long and 2.5 wide — about the width of a DNA strand. Even so, it was the heftiest contender in the first-ever nanocar race earlier this year. This pip-squeak vehicle took home the bronze, but perhaps more importantly, researchers made a surprising observation while manufacturing this model of nanoracer.
About 90 percent of the Bobcat Nanowagons that researchers produced broke apart when the scientists tried attaching them to a racetrack. Most broken bits looked like two-wheel hoverboards.

“It’s very surprising that it seems to be easier to break the chassis than to remove the wheel from the chassis,” study coauthor Eric Masson said August 23 in a news conference at the American Chemical Society Meeting. The type of chemical bond linking atoms in the car frame is typically thought to be stronger than the kind of bond attaching its wheels.

Masson, a chemist at Ohio University in Athens, and colleagues aren’t sure why the Bobcat Nanowagon was more liable to snap in half than lose a wheel. Explaining this chemical quirk could help scientists better understand the operations of molecular machines, which may be useful for transporting information in electronic devices or delivering drugs to specific cells (SN: 10/29/16, p. 6).

Shellfish stowaways on boat hulls could become castaways, thanks to a superslippery material.

Crowds of mussels can grab onto ships, piers and other infrastructure. They slow down the boats they commandeer, and they’re expensive to remove. The hitchhikers can even travel to new places and become invasive species (SN: 3/18/17, p. 30). A new lubricant-infused material could one day help prevent mussels from getting a grip in the first place, scientists report in the Aug. 18 Science.
Researchers modified a flexible silicone material to which Asian green mussels (Perna viridis) ordinarily stick liberally, suffusing it with a silicone lubricant. Some of the lubricant forms a thin, liquid layer and smooths out any microscopic roughness on the material’s surface; the rest creates a reservoir within the material’s pores. When the top layer wears off, the reservoir replenishes it.

Normally, mussels probe a surface with a footlike appendage and then send out a sticky thread to latch on. But mussels trying to attach to the lubricant-infused material either didn’t send out those threads at all or directed them to the wrong target — to the animals’ own shell or a different surface. That misfire suggests that the shellfish didn’t recognize the lubricated surface as a place to cling to, says study coauthor Joanna Aizenberg, an engineer at Harvard University.
She and colleagues are already commercializing lubricated coatings for use in other applications, such as implanted medical devices where it’s crucial that blood or bacteria not hold on to a surface. Next stop, the slippery coatings could take to the seas.