Artificial cells made from scratch in the lab could one day offer a more effective, patient-friendly diabetes treatment.

Diabetes, which affects more than 400 million people around the world, is characterized by the loss or dysfunction of insulin-making beta cells in the pancreas. For the first time researchers have created synthetic cells that mimic how natural beta cells sense blood sugar concentration and secrete just the right amount of insulin. Experiments with mice show that these cells can regulate blood sugar for up to five days, researchers report online October 30 in Nature Chemical Biology.
If the mouse results translate to humans, diabetics could inject these artificial beta cells to automatically regulate their blood sugar levels for days at a time.

That would be a “a huge leap forward” for diabetic patients who currently have to check their blood sugar and inject insulin several times a day, says Omid Veiseh, a bioengineer at Rice University in Houston who wasn’t involved in the research. “Even if it were just a one-day thing, it would still be impressive,” he says.
Fashioned from human-made materials and biological ingredients like proteins, these faux cells contain insulin-filled pouches much like the insulin-carrying compartments inside real beta cells. And, similar to a natural beta cell, when one of these artificial beta cells is surrounded by excess blood sugar, its insulin sacs fuse with its outer membrane and eject insulin into the bloodstream. As blood sugar levels drop, insulin packets stop fusing with the membrane, which stems the cell’s insulin secretion.
Fabricating artificial insulin delivery systems that actually imitate the inner workings of real beta cells for ultrafine blood sugar regulation is “an engineering feat,” says Patrik Rorsman, a diabetes researcher at the University of Oxford who wasn’t involved in the work. The cellular imitations are “not as perfect as the beta cells we’re equipped with when we’re healthy,” he adds. For one thing, the faux cells eventually run out of insulin to release. But Rorsman believes that such artificial cells present a viable diabetes treatment.
Unlike transplanted beta cells — or other types of real cells genetically engineered to release insulin for diabetes treatment (SN: 1/15/11, p. 9) — these artificial cells could be mass-produced and have a much longer shelf life than live cells, says study coauthor Zhen Gu, a biomedical engineer at the University of North Carolina at Chapel Hill.

When Gu and colleagues injected their synthetic cells into diabetic mice, the animals’ blood sugar levels normalized within an hour and stayed that way up to five days, when the cells ran out of insulin. The researchers plan to perform further tests on lab animals to assess the fake cells’ long-term health effects before running clinical trials.

Even for patients who manage their insulin with automated mechanical pumps (SN Online: 5/8/10), synthetic cells offer the advantage of more precise, real time blood sugar regulation, says Michael Strano, a bioengineer at MIT. The creation of the new faux cells not only poses a potential diabetes treatment, “but it’s also a bellwether. It’s slightly ahead of its time,” says Strano. “I think therapeutics of the future are going to look like this.”

Much of what happens on the Earth’s surface is connected to activity far below. “Beneath Our Feet,” a temporary exhibit at the Norman B. Leventhal Map Center in the Boston Public Library, explores the ways people have envisioned, explored and exploited what lies underground.

“We’re trying to visualize those places that humans don’t naturally go to,” says associate curator Stephanie Cyr. “Everybody gets to see what’s in the sky, but not everyone gets to see what’s underneath.”
“Beneath Our Feet” displays 70 maps, drawings and archaeological artifacts in a bright, narrow exhibit space. (In total, the library holds a collection of 200,000 maps and 5,000 atlases.) Many objects have two sets of labels: one for adults and one for kids, who are guided by a cartoon rat mascot called Digger Burrows.

The layout puts the planet’s long history front and center. Visitors enter by walking over a U.S. Geological Survey map of North America that is color-coded to show how topography has changed over geologic time.
Beyond that, the exhibit is split into two main themes, Cyr says: the natural world, and how people have put their fingerprints on it. Historical and modern maps hang side by side, illustrating how ways of thinking about the Earth developed as the tools for exploring it improved.

For instance, a 1665 illustration drawn by Jesuit scholar Athanasius Kircher depicts Earth’s water systems as an underground network that churned with guidance from a large ball of fire in the planet’s center, Cyr says. “He wasn’t that far off.” Under Kircher’s drawing is an early sonar map of the seafloor in the Pacific Ocean, made by geologists Marie Tharp and Bruce Heezen in 1969 (SN: 10/6/12, p. 30). Their maps revealed the Mid-Atlantic Ridge. Finding that rift helped to prove the existence of plate tectonics and that Earth’s surface is shaped by the motion of vast subsurface forces.

On another wall, a 1794 topological-relief drawing of Mount Vesuvius — which erupted and destroyed the Roman city of Pompeii in A.D. 79 — is embellished by a cartouche of Greek mythological characters, including one representing death. The drawing hangs above a NASA satellite image of the same region, showing how the cities around Mount Vesuvius have grown since the eruption that buried Pompeii, and how volcano monitoring has improved.

The tone turns serious in the latter half of the exhibit. Maps of coal deposits in 1880s Pennsylvania sit near modern schematics explaining how fracking works (SN: 9/8/12, p. 20). Reproductions of maps of the Dakotas from 1886 may remind visitors of ongoing controversies with the Dakota Access Pipeline, proposed to run near the Standing Rock Sioux Reservation, and maps from the U.S. Environmental Protection Agency mark sites in Flint, Mich., with lead-tainted water.

Maps in the exhibit are presented dispassionately and without overt political commentary. Cyr hopes the zoomed-out perspectives that maps provide will allow people to approach controversial topics with cool heads.

“The library is a safe place to have civil discourse,” she says. “It’s also a place where you have access to factual materials and factual resources.”

An immune system mainstay in the fight against viruses may harm rather than help a pregnancy. In Zika-infected mice, this betrayal appears to contribute to fetal abnormalities linked to the virus, researchers report online January 5 in Science Immunology. And it could explain pregnancy complications that arise from infections with other pathogens and from autoimmune disorders.

In pregnant mice infected with Zika virus, those fetuses with a docking station, or receptor, for immune system proteins called type I interferons either died or grew more poorly compared with fetuses lacking the receptor. “The type I interferon system is one of the key mechanisms for stopping viral infections,” says Helen Lazear, a virologist at the University of North Carolina at Chapel Hill, who coauthored an editorial accompanying the study. “That same [immune] process is actually causing fetal damage, and that’s unexpected.”
Cells infected by viruses begin the fight against the intruder by producing type I interferons. These proteins latch onto their receptor on the surfaces of neighboring cells and kick-start the production of hundreds of other antiviral proteins.

Akiko Iwasaki, a Howard Hughes Medical Institute investigator and immunologist at Yale School of Medicine, and her colleagues were interested in studying what happens to fetuses when moms are sexually infected with Zika virus. The researchers mated female mice unable to make the receptor for type I interferons to males with one copy of the gene needed to make the receptor. This meant that moms would carry some pups with the receptor and some without in the same pregnancy.

Pregnant mice were infected vaginally with Zika at one of two times — one corresponding to mid‒first trimester in humans, the other to late first trimester. Of the fetuses exposed to infection earlier, those that had the interferon receptor died, while those without the receptor continued to develop. For fetuses exposed to infection a bit later in the pregnancy, those with the receptor were much smaller than their receptor-lacking counterparts.

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The fetuses without the receptor still grew poorly due to the Zika infection, which is expected given their inability to fight the infection. What was striking, Iwasaki says, is that the fetuses able to fight the infection were more damaged, and were the only fetuses that died.

It’s unclear how this antiviral immune response causes fetal damage. But the placentas—which, like their fetuses, had the receptor — didn’t appear to provide those fetuses with enough oxygen, Iwasaki says.

The researchers also infected pregnant mice that had the receptor for type I interferons with a viral mimic — a bit of genetic material that goads the body to begin its antiviral immune response — to see if the damage happened only during a Zika infection. These fetuses also died early in the pregnancy, an indication that perhaps the immune system could cause fetal damage during other viral infections, Iwasaki notes.

Iwasaki and colleagues next added type I interferon to samples of human placental tissue in dishes. After 16 to 20 hours, the placental tissues developed structures that resembled syncytial knots. These knots are widespread in the placentas of pregnancies with such complications as preeclampsia and restricted fetal growth.

Figuring out which of the hundreds of antiviral proteins made when type I interferon ignites the immune system can trigger placental and fetal damage is the next step, says Iwasaki. That could provide more understanding of miscarriage generally; other infections that cause congenital diseases, like toxoplasmosis and rubella; and autoimmune disorders that feature excessive type I interferon production, such as lupus, she says.

We’re going to need a bigger trash can.

A pooling of plastic waste floating in the ocean between California and Hawaii contains at least 79,000 tons of material spread over 1.6 million square kilometers, researchers report March 22 in Scientific Reports. That’s the equivalent to the mass of more than 6,500 school buses. Known as the great Pacific garbage patch, the hoard is four to 16 times as heavy as past estimates.

About 1.8 trillion plastic pieces make up the garbage patch, the scientists estimate. Particles smaller than half a centimeter, called microplastics, account for 94 percent of the pieces, but only 8 percent of the overall mass. In contrast, large (5 to 50 centimeters) and extra-large (bigger than 50 centimeters) pieces made up 25 percent and 53 percent of the estimated patch mass.
Much of the plastic in the patch comes from humans’ ocean activities, such as fishing and shipping, the researchers found. Almost half of the total mass, for example, is from discarded fishing nets. A lot of that litter contains especially durable plastics, such as polyethylene and polypropylene, which are designed to survive in marine environments.
To get the new size and mass estimates, Laurent Lebreton of the Ocean Cleanup, a nonprofit foundation in Delft, the Netherlands, and his colleagues trawled samples from the ocean surface, took aerial images and simulated particle pathways based on plastic sources and ocean circulation.
Aerial images provided more accurate tallies and measurements of the larger plastic pieces, the researchers write. That could account for the increase in mass over past estimates, which relied on trawling data and images taken from boats, in addition to computer simulations. Another possible explanation: The patch grew — perhaps driven by an influx of debris from the 2011 tsunami that hit Japan and washed trash out to sea (SN: 10/28/17, p. 32).

BOSTON — The bond between parent and child is powerful enough to override fear. New research shows that if a parent sits with a young child during a potentially scary situation, the child isn’t as afraid of it later.

The study is in line with research suggesting that during particular stages of development, a strong connection with a caregiver tamps down activity in the amygdala, the brain structure that helps process fear and spurs the fight-or-flight response.
“Fight or flight is pointless if you are tiny,” said developmental neuroscientist Nim Tottenham of Columbia University, who presented the work March 26 at a Cognitive Neuroscience Society meeting. For young kids, the bond with a caregiver not only helps ensure survival but also makes kids feel safe, enabling them to approach the world with confidence, Tottenham said. “Attachment is a strategy that has worked very well; it trumps everything.”

Kids from ages 3 to 5 were shown two shapes — a green triangle and a blue square. Just the square was accompanied by a loud, fingers-on-the-chalkboard kind of noise. Some kids had a parent sitting next to them while they saw the shapes; others sat with a researcher. After the parents left, kids chose which door to go through to get a present: one with the scary blue square on it, the other with the innocuous green triangle.

Kids paired with the experimenter avoided the door with the blue square. But kids who had sat next to a parent showed a slight preference for that door, even though they knew they would collect the same present from behind either door.

Stephen Hawking, a black hole whisperer who divined the secrets of the universe’s most inscrutable objects, left a legacy of cosmological puzzles sparked by his work, and inspired a generation of scientists who grew up reading his books.

Upon Hawking’s death on March 14 at age 76, his most famous discovery — that black holes aren’t entirely black, but emit faint radiation — was still fueling debate.

Hawking “really, really cared about the truth, and trying to find it,” says physicist Andrew Strominger of Harvard University, who collaborated with the famed scientist. Hawking “was deeply committed, his whole life, to this quest of understanding more about the physical universe around us.”

After earning his Ph.D. in 1965 at the University of Cambridge, Hawking continued studying cosmology there for the rest of his life. Due to a degenerative illness, amyotrophic lateral sclerosis, or ALS, Hawking gradually lost control of his body, requiring a wheelchair and eventually a voice synthesizer to speak. Yet his desire to uncover nature’s secrets remained boundless.
In one of the most significant realizations of his career, Hawking reported in 1974 that black holes emit a faint glow of particles. This effect arises from quantum mechanics, which states that a sea of transient particles and antiparticles pervades all of space. These “virtual” particles usually annihilate in an instant, but if one of those particles is lost inside a black hole’s boundary, or event horizon, its partner can escape, producing what’s now known as Hawking radiation (SN: 5/31/14, p. 16).

As a result, black holes can gradually evaporate and disappear. This led to a still unresolved paradox: Throw an encyclopedia into a black hole and the information will eventually be lost. But according to quantum mechanics, information can never be destroyed.

Many solutions have been proposed for this problem, but none has stuck. In 2016, Hawking and colleagues proposed a path toward a solution: Black holes might have “soft hair,” low-energy particles that would retain information about what fell inside (SN: 2/06/16, p. 16). Hawking’s collaborators, including Strominger, are still working on the research. Standing at the interface between two seemingly incompatible theories — quantum mechanics, which describes the very small, and the general theory of relativity, which describes gravity — the quandary and its resolution may eventually help reveal a unified theory of quantum gravity.

Hawking made many other contributions, including studies of spacetime curvature during the Big Bang and the possibility that mini black holes might have formed in the universe’s infancy. Despite their groundbreaking nature, Hawking’s ideas remained largely theoretical, says Harvard theoretical astrophysicist Avi Loeb. Hawking radiation, for example, has never been directly detected. “That’s, unfortunately, why he didn’t get the Nobel Prize,” Loeb says.
Yet Hawking achieved a level of fame uncommon among scientists. He excelled at making abstruse science digestible to the public. With his books, most notably the best-selling A Brief History of Time, first published in 1988, Hawking inspired countless future scientists and science lovers (including the author of this article). Theoretical cosmologist Katie Mack of North Carolina State University in Raleigh first opened the book when she was about 10 years old. “I found it so fascinating at the time,” she says. “I found out that Stephen Hawking was called a cosmologist and so I said I wanted to be a cosmologist.” Hawking similarly motivated dozens of her colleagues, Mack says.

Hawking remained active in research even in the last months of his life. A paper on which he is a coauthor, which was updated in the weeks before his death, considered the physics of multiverses, the possibility that a slew of other universes exist in addition to our own.

A funeral was held for Hawking on March 31. Later this year, his ashes will be interred in Westminster Abbey in London, where they will rest alongside the remains of other famous British scientists, including Isaac Newton and Charles Darwin.

While the data was amassing, suddenly there came a tapping,
As of something gently rapping, rapping at LIGO’s door.

The source of a mysterious glitch in data from a gravitational wave detector has been unmasked: rap-tap-tapping ravens with a thirst for shaved ice. At the Advanced Laser Interferometer Gravitational-Wave Observatory, or LIGO, in the desert of Hanford, Wash., scientists noticed a signal that didn’t look like gravitational waves, physicist Beverly Berger said on April 16 at a meeting of the American Physical Society.

A microphone sensor that monitors LIGO’s surroundings caught the sounds of pecking birds on tape in July 2017, Berger, of the LIGO Laboratory at Caltech, said. So the crew went out to the end of one of the detector’s 4-kilometer-long arms to check for evidence of the ebony birds at the scene.

Sure enough, frost covering a pipe connected to the cooling system was covered in telltale peck marks from the thirsty birds. One raven, presumably seeking relief from the desert heat, was caught in the act. Altering the setup to prevent ice buildup now keeps the ravens from tapping, evermore.

After a two-day delay, the planet-hunting TESS telescope successfully launched into a clear blue sky at Cape Canaveral, Fla., at 6:51 p.m. EDT on April 18.

TESS, the Transiting Exoplanet Survey Satellite, is headed to an orbit between the Earth and the moon, a journey that will take about two months. In its first two years, the telescope will seek planets orbiting 200,000 nearby, bright stars, and identify the best planets for further study. TESS’ cameras will survey 85 percent of the sky by splitting it up into 26 zones and focusing on each zone for 27 days apiece.

TESS launched on a SpaceX Falcon 9 rocket. A previous launch attempt on April 16 was scrubbed so that SpaceX could run more tests on the rocket’s guidance, navigation and control system. SpaceX recovered the rocket’s first stage booster on an autonomous drone ship and hopes to reuse the rocket on a future launch.

Quantum entanglement has left the realm of the utterly minuscule, and crossed over to the just plain small. Two teams of researchers report that they have generated ethereal quantum linkages, or entanglement, between pairs of jiggling objects visible with a magnifying glass or even the naked eye — if you have keen vision.

Physicist Mika Sillanpää and colleagues entangled the motion of two vibrating aluminum sheets, each 15 micrometers in diameter — a few times the thickness of spider silk. And physicist Sungkun Hong and colleagues performed a similar feat with 15-micrometer-long beams made of silicon, which expand and contract in width in a section of the beam. Both teams report their results in the April 26 Nature.
“It’s a first demonstration of entanglement over these artificial mechanical systems,” says Hong, of the University of Vienna. Previously, scientists had entangled vibrations in two diamonds that were macroscopic, meaning they were visible (or nearly visible) to the naked eye. But this is the first time entanglement has been seen in macroscopic structures constructed by humans, which can be designed to meet particular technological requirements.

Entanglement is a strange feature of quantum mechanics, through which two objects’ properties become intertwined. Measuring the properties of one object immediately reveals the state of the other, even though the duo may be separated by a large distance (SN: 8/5/17, p. 14).

Quantum mechanics’ weird rules typically apply to small fry — atoms, electrons and other tiny particles — and not to larger things such as cats, chairs or buildings. But that division leads to a confounding puzzle. “Atoms behave like atoms, and cats behave like cats, and so where is that transition in between?” says physicist Ben Sussman of the National Research Council of Canada in Ottawa, who was not involved in the research.

Now, scientists are extending the dividing line to larger and larger objects. “One of our motivations is to keep on testing how far we can push quantum mechanics,” says Sillanpää, of Aalto University in Finland. “There might be some fundamental limit for how big objects can be” and still be quantum.
In Sillanpää’s experiment, two tiny aluminum sheets — consisting of about a trillion atoms and just barely visible with the naked eye — vibrate like drumheads and interact with microwaves bouncing back and forth in a cavity. Those microwaves play the role of drum major, causing the two drumheads to sync up their motions. In many previous demonstrations of entanglement, the delicate quantum link is transient. But this one was long-lived, persisting as long as half an hour in experiments, Sillanpää says, and, in theory, even longer. “Our entanglement lasts forever, basically.”
Taking a different tactic, Hong and colleagues demonstrated entanglement with two silicon beams, big enough to be seen with a magnifying glass. Within a region of each beam, in a 1-micrometer-long section composed of about 10 billion atoms, the structure expanded and contracted — as if taking deep breaths in and out — in response to being hit with light. Instead of microwaves, Hong and colleagues’ work used infrared light of the wavelength typically transmitted in telecommunications networks made of optical fibers, which means it could be incorporated into a future quantum internet. “From a technology standpoint, that really is crucial,” says physicist John Teufel of the National Institute of Standards and Technology in Boulder, Colo., who was not involved with the work.

Scientists could use such vibrating structures within a quantum network to convert quantum information from one type to another, transitioning from particles of light to vibrations, for example. Once constructed, a quantum internet could allow quantum computers to communicate and provide unhackable communication across the globe (SN: 10/15/16, p. 13).

The ability to entangle these specially designed structures moves scientists a step closer to that vision. “You can really start to think about building real devices with these things,” Sussman says.

New insights into how stars like the sun die might help explain why astronomers find bright planetary nebulae where they’re least expected. Simulations of how these stellar remnants form suggest that smaller stars have cores that heat up fast enough to produce bright nebulae upon their demise, researchers report online May 7 in Nature Astronomy.

A planetary nebula is what’s left over when a sunlike star sheds its outer envelope of gas. Radiation from the stellar core, now exposed, sets the expanding shell of gas aglow, creating the kind of candy-colored clouds seen in spectacular Hubble Space Telescope images, like that of the Cat’s Eye Nebula and the butterfly-shaped NGC 6302 (SN Online: 9/5/13).
Astronomers had thought a star’s mass dictated what sort of nebula it produced, with more massive stars creating the brightest nebulae and stars with lower masses, like the sun, making nebulae too faint to see from another galaxy.

But that idea didn’t match observations: The brightest planetary nebulae in older elliptical galaxies — thought to be home to only low-mass stars — are just as luminous as those in younger, spiral galaxies, where massive stars abound. The puzzle vexed astronomers for decades.

Now, astrophysicist Albert Zijlstra at the University of Manchester in England, and colleagues have simulated planetary nebulae formation based on a new theory of stellar evolution. This theory says that after smaller stars shed their outer envelopes, their bare cores heat up more quickly than previously thought. That allows the cinderlike stellar core to pump more energetic radiation into the surrounding nebula before the gas expands too far out into space, ultimately making for a brighter nebula, explains Christophe Morisset, an astronomer at the National Autonomous University of Mexico in Mexico City not involved in the work.

Simulations showed that stars ranging from 1.1 to three times the mass of the sun produce nebulae with similar brightness. That result could explain why nebulae found in galaxies with stars that are 7 billion years old can be just as bright as those found in galaxies chock-full of 1-billion-year-old stars.
This finding marks “an important step forward” in understanding the universe’s population of planetary nebulae, says Penn State astronomer Robin Ciardullo, who was not involved in the work.

But some mystery still remains: For the most ancient elliptical galaxies with very small stars over 7 billion years old, the simulations didn’t produce planetary nebulae bright enough to match what astronomers see in the sky. So there’s still “a little ways to go” before astronomers can explain why bright nebulae are so ubiquitous, he says.