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Hurricane season has officially begun in the North Atlantic, and it’s not just coastal communities that have to worry. A population of sooty terns off the southwest tip of Florida might want to worry, too. Depending on when and where storms hit, the terns could be in for a tough time. Their migratory route overlaps with the general path of hurricanes traveling from the waters off Africa up to the United States, a new study finds.

Sooty terns can be found all over the world. But the ones that nest in the Dry Tortugas National Park, west of Key West, are among the best known. The birds have been the subject of a long-term study that started back in 1959, and of other studies that stretch back into the early 20th century. Those studies revealed much about the birds’ growth and behavior, but not much about the terns’ migration.

In 2011, Stuart Pimm, an ecologist at Duke University, and colleagues attached geolocators to 25 sooty terns. A geolocator is “a remarkably stupid device,” Pimm says. It simply records how bright it is every 12 minutes. From that information, researchers can determine sunrise and sunset from day to day — and therefore approximate the birds’ location. But they have to retrieve the devices to get the data. That meant finding those 25 birds in a population of 80,000.

The researchers managed to find two.

But those two birds had some remarkable data. The geolocators recorded that the birds had experienced a 12-hour day in December, offset by five hours from Florida. That meant that they had been flying somewhere around the equator and were headed toward Africa.

But perhaps those two birds were outliers. So in 2014, Pimm’s group got some more sophisticated technology that could transmit a bird’s location. The new tech was also a lot more expensive, so the scientists were able to track only five birds. But the researchers also didn’t have to wait a year to get the data — or search for the birds among a population of thousands. “I would get up every day and check on where the birds were,” Pimm recalls.

At least some of the terns were flying south through the Caribbean, southeast along the coast of South America and then to the middle of the Atlantic, where they spent the winter, the team reports May 10 in PeerJ.
It’s a path that takes the birds straight up hurricane alley the long way, Pimm notes.

The researchers then took advantage of all those decades of banding birds. They matched historical reports from 1960 to 1980 of wrecked (that is, dead) sooty terns with tropical storms and hurricanes. Some years the birds were fine, but, Pimm says, “some years they get absolutely slaughtered.” If a storm hits at the wrong place and the wrong time, the birds are out of luck. Even if they manage to survive the high winds and heavy rains, they can be blown far off course. Hurricane Camille, for instance, took one poor sooty tern to the Great Lakes in 1969.

In some years, hurricanes may take out a small portion of the sooty tern population, but it doesn’t appear to be enough to cause big declines. Pimm worries, though, about what might happen in the future. It is not yet clear how climate change might change the severity or frequency of hurricanes — and thus affect the terns — but it is something to keep an eye on, Pimm says.

Zuul is back. But don’t bother calling the Ghostbusters. Zuul crurivastator is a dino, not a demon. A 75-million-year-old skeleton unearthed in Montana in 2014 reveals a tanklike dinosaur with a spiked club tail and a face that probably looked a lot like its cinematic namesake.

The find is the most complete fossil of an ankylosaur, a type of armored dinosaur, found in North America, researchers report May 10 in Royal Society Open Science. It includes a complete skull and tail club, plus some preserved soft tissue, says study co-author Victoria Arbour, a paleobiologist at the Royal Ontario Museum in Toronto. “It really gives us a good idea of what these animals looked like.”
The bones reveal that Z. crurivastator had spikes running all the way down its tail, not just on the club itself. That arrangement means the weaponry was more than just a “massive sledgehammer,” Arbour says. The club was a formidable weapon. The term crurivastator comes from the Latin for “shin destroyer.”
Arbour previously created mathematical models to calculate the force with which similar ankylosaurs might have swung their tails. These appendages provided a winning combination: good at absorbing impacts and able to smack an opponent hard enough to hurt, she says. Despite their armor and fearsome tail, ankylosaurs were plant eaters. So they probably used their tails to smack predators or compete with other ankylosaurs.

Arbour and museum colleague David Evans plan to investigate the thin sheet of fingernail-like material covering the bony plates on the tail, along with other details of the fossil that are typically lost in such old specimens. The rare, preserved soft tissue might even let scientists extract ancient proteins, Arbour says, providing insight into how these building blocks of life have changed since the days of dinos.

Having all this material in hand, she says, “kind of pushes the envelope about what we can identify in the fossil record.”

Once every 53 days, Jupiter pulls Juno close. Locked in orbit since July 2016, the spacecraft has made five close flybys of the planet so far. More than 1,300 Earths could fit inside Jupiter, but Juno takes only two hours to zip from pole to pole. That mad, north-to-south trek is shown below in a sequence of 14 enhanced-color images taken May 19.

Each image’s width corresponds to the width of the field of view of JunoCam, Juno’s visible light camera. As the spacecraft zooms closer, to about 3,400 kilometers above the cloud tops, less total area of Jupiter can be seen, but more details emerge. Turbulent clouds, for example, signal massive tempests along the equator. New data from the mission reveal that near the equator, ammonia rises from unexpectedly deep in the Jovian atmosphere (SN Online: 5/25/17). Such upwelling might fuel storms like these, but it’s too early for scientists to tell. And what look like pinpricks of light across the entire south tropical zone are actually 50-kilometer-wide cloud towers. Found high in Jupiter’s atmosphere, these clouds are probably made of ice crystals.
“It’s snowing on Jupiter, and we’re seeing how it works,” said Juno mission leader Scott Bolton of the Southwest Research Institute in San Antonio in a May 25 news conference. Or “it could be hail,” he added. Either way, it’s not snow or hail as we know it. The precipitation is probably mostly ammonia ice, but there may be water ice, too.

Juno doesn’t have eyes only for Jupiter. Sometimes the spacecraft stargazes, too. On its initial science flyby last August, Juno captured the first image of Jupiter’s main ring seen from the inside looking out. In the background of the newly released image, Betelgeuse, in the constellation Orion, peeks above the gauzy band, and the three stars of Orion’s belt glint from the bottom right. Taken with Juno’s star-tracking navigation camera, the shot reveals that “heaven looks the same to us from Jupiter,” said Heidi Becker, leader of Juno’s radiation monitoring team at NASA’s Jet Propulsion Laboratory in Pasadena, Calif.

People with weakened immune systems might help scientists get a jump on the flu virus.

Some flu virus mutations popped up again and again in cancer patients with long-term infections, researchers report June 27 in eLife. And some of those mutations were the same as ones found in flu viruses circulating around the world a few years later, evolutionary virologist Jesse Bloom of the Fred Hutchinson Cancer Research Center in Seattle and colleagues discovered. The findings may eventually help vaccine developers predict flu strain evolution.
“You can’t predict what’s going to happen next year,” — at least not yet, Bloom says. But monitoring infections in many people may indicate which parts of the virus are most likely to change in the future.

Most people who catch the flu get over it in about a week. Previous studies have suggested that the virus doesn’t change much within one person. It must pass through tens to hundreds of people to build up enough mutations to give it an advantage over other flu viruses, Bloom says. That makes predicting flu evolution tricky.

A coffee shop conversation alerted Bloom to a potential treasure: multiple nasal wash samples from four cancer patients who had had the flu for months in 2006 and 2007. Part of their cancer treatments had weakened all four people’s immune systems, making it hard for them to fight off the infections.

Evolutionary biologist Katherine Xue in Bloom’s lab and colleagues examined genetic material from the nasal washes, identifying mutations present in at least 5 percent of flu viruses in each person. The team tracked competition between virus variants within each person over time and compared virus evolution patterns among the patients.

Nine flu mutations popped up in at least two separate patients. Of those, five were in the virus’s hemagglutinin gene. That gene encodes a sugar-studded protein on the virus’s outer surface that helps the virus stick to and invade human cells. The immune system commonly makes antibodies against hemagglutinin that foil the strain’s ability to infect the host again. As a result, the virus has to mutate so that the protein will be different enough to evade the immune system.
Four amino acids of the hemagglutinin protein were frequently changed by mutations in the cancer patients’ viruses and popped up years later in flu strains worldwide, too. Those amino acids are the 138th, 193rd, 223rd and 225th links in the chain of amino acids that make up the hemagglutinin protein.

In some cases, the mutations produced the same amino acid change in both the cancer patients’ and the global virus strains circulating after 2010. For instance, the amino acid valine was altered to isoleucine at position 223. That happened in two cancer patients in 2006 and 2007. After about 2012, nearly all viruses circulating worldwide had the same change.

In another case, those same two cancer patients’ viruses had tyrosine at position 193, but globally circulating viruses had either phenylalanine or serine at that position, the researchers found. Those results indicate that at some spots in the protein, particular changes are important, but other positions are more malleable.

Within patients, viruses carrying different amino acids seemed to directly compete against each other; as one became more frequent, the other was reduced in abundance. That’s the same sort of pattern researchers observe at the global level. Knowing which mutations commonly win competitions in immune-compromised patients may give a preview of winners in the global flu fight.

Not all of the flu mutations that arose in the cancer patients were later found in the general population, says infectious disease biologist Katia Koelle of Duke University. For instance, a mutation called L427F (changing leucine at position 427 to phenylalanine) was found in more than 75 percent of flu viruses in three of the cancer patients, but it was never seen in flu viruses circulating globally. That mutation might give flu viruses some advantage within a person, but might not be efficient at spreading from person-to-person, Koelle says. Studies that compare flu alterations in multiple people won’t immediately tell researchers how to design vaccines, she says, but could point to parts of the virus for further investigation.

Xue and Bloom say they would like to repeat the study, perhaps this time in very young children and elderly people — two groups that also have weaker immune systems than most adults.

Jupiter’s Great Red Spot is ready for its close-up. On July 10, NASA’s Juno spacecraft will fly directly over it, providing the first intimate views of Jupiter’s most famous feature.

The Great Red Spot is a 16,000-kilometer-wide storm that’s been raging for centuries. Juno will soar just 9,000 kilometers above the Red Spot’s swirling clouds, collecting data with its eight scientific instruments and snapping pictures with its JunoCam imager.

Since Juno started orbiting Jupiter last July, it’s revealed many new, sometimes surprising insights into the planet’s structure, atmosphere, and magnetic field. The forthcoming Red Spot observations are expected to help scientists understand what drives Jupiter’s iconic storm.

Physicists have now probed the memory of Maxwell’s demon, a devious, hypothetical beast. By peeking at information retained by a laboratory version of the creature, scientists confirmed the role of information in saving the second law of thermodynamics from the onslaught of a tiny, superpowerful being intent on wreaking havoc.

In work reported online July 3 in the Proceedings of the National Academy of Sciences, a team of researchers created a quantum version of Maxwell’s demon in the lab and measured both the information stored in its memory and the energy it extracted from a system. The results directly illustrate that information plays a key role in the demon’s attempts to distill energy.
Since 1867, when the demon was proposed by physicist James Clerk Maxwell, scientists wondered whether such a creature could violate the second law, a sacred tenet of physics. It declares that the entropy, or disorder, of a closed system cannot decrease over time.

Maxwell suggested that a nefarious tiny being could shuttle around molecules to decrease entropy — for example, by putting all the fast-moving molecules on one side of a box containing a gas and the slower ones on the other side. Such an improbable reconfiguration would break the second law, allowing the demon to illegally siphon off energy.

A century later, a solution to this dilemma was found: The demon must record information about the molecules in order to manipulate them, and that information has physical relevance. Storing that information in its “brain” increases the entropy of the demon, compensating for the entropy decrease the demon produces. As the demon extracts energy, it must delete the contents of its memory in order to store new information and manipulate other molecules. That deletion, physicist Rolf Landauer determined in 1961, costs energy and releases entropy, with the result that the demon’s energy harvest is negated.

To show that the demon indeed remembered the properties of the system, the researchers probed the quantum state of the demon’s memory.

“The state of the memory is very important,” says physicist Juan Parrondo of Complutense University of Madrid, because it is what confirms that the second law still holds. “This is the first experiment which really addresses this question,” says Parrondo, who was not involved with the research.
In the experiment, performed by physicist Benjamin Huard and colleagues, the demon extracts energy from the system, a tiny circuit made of superconducting metal, which can carry electricity without resistance. Light tuned to a particular frequency causes the system to jump from a low-energy to high-energy state, or vice versa, absorbing or emitting a photon, or particle of light, in the process. The demon — a superconducting cavity within which microwaves bounce back and forth — manipulates the system to ensure that energy can be drained from the system, but not absorbed, allowing the demon to capture the energy released.

If the system is in the high-energy state, the demon allows the system to drop to lower energy, in the process spitting out a photon, which the demon can harvest for energy. But if the system is in the low-energy state, the demon prevents it from absorbing photons. The net result: Energy is sapped from the circuit. But, says Huard, of École Normale Supérieure de Lyon in France, “the information the demon learns about the system is encoded into its memory.”

The researchers probed this memory through a process called quantum tomography — meaning that they repeated the experiment many times and cataloged the state of the memory. The results revealed that, as expected, the demon retained the information about what energy state the system was in.

In addition to reading the demon’s mind, the researchers measured the work extracted from the system in a more direct manner than previous experiments. “This is one new feature of this implementation,” says Roberto Serra of Federal University of ABC in Santo André, Sao Paulo, Brazil. “This work is a very nice experiment.”

In Huard’s scheme — in contrast to some previous experiments — the demon and the system both operate on a quantum level. While the rules of thermodynamics were originally understood only for large systems like steam engines, scientists now hope understanding how the rules translate to small scales could one day lead to designs for more efficient quantum machines (SN: 3/19/16, p. 18).

A majority of football players whose brains were donated for research suffered a degenerative brain disease during their lives, according to the largest sample of players ever studied. The finding provides more evidence that the repetitive injuries to the brain sustained while playing American football are associated with the disease, researchers say.

Of 202 deceased former football players, 177 were diagnosed with chronic traumatic encephalopathy, which can cause a host of mood and behavioral issues as well as thinking and reasoning problems. Among 111 men who had played in the National Football League, 110 — a whopping 99 percent — had developed the disease, researchers report July 25 in JAMA. Three of 14 high school players also showed signs of the brain disease, as well as 48 of 53 college players. Researchers relied on brain autopsies of the players to make the diagnoses and interviewed family members and friends about the symptoms players had experienced.
This doesn’t necessarily mean all football players experience chronic traumatic encephalopathy. Many of the families who donated the brains for research could have been motivated to do so because their loved ones had noticeable symptoms, so the sample is not necessarily representative of the general football population. The results are still worrisome, though, researchers say.
“The fact that chronic traumatic encephalopathy was so common adds to our concern about the safety of playing football and the risk of developing neurologic symptoms later in life,” says neurologist Gil Rabinovici of the University of California, San Francisco, who wrote an editorial accompanying the article. This “hovers like a dark cloud over the game at all levels, even if the study cannot address how frequent the disease is, or who is at risk.”

Chronic traumatic encephalopathy, or CTE, shows up in athletes and others who’ve had repetitive injuries to the head, such as concussions. The only way to diagnose the disease is with an autopsy. In brains with the condition, a protein called tau goes “bad” and forms clumps in nerve cells and other brain cells. Although tau buildup is found in other brain diseases, like Alzheimer’s, in CTE, the protein congregates in brain cells around small blood vessels.
In 2008, a research team set up a brain bank to study the impact of head blows resulting from contact sports or military service. Behavioral neurologist Jesse Mez of Boston University School of Medicine and his colleagues classified players as having mild or severe CTE, depending on how widespread the tau clumps were in the players’ brains. The severity of disease seemed to track with the number of years spent playing football, says Mez. Among NFL players, 95 of the 110 diagnosed cases were severe. All three of the high school players’ cases were mild, while just over half of the college players’ cases were severe.

Yet the players’ reported symptoms while alive were similar, regardless of the severity seen in the brain. Behavioral and mood problems, such as impulsivity, anxiety and depression, were commonly reported in both severe and mild cases of the disease. Cognitive symptoms, including memory loss, were also typical for both groups. One major difference, Mez notes, was that dementia was more common in severe cases of CTE than in mild cases.

As for why players reportedly experienced similar symptoms no matter the severity, “the question is, is there something else going on,” such as inflammation, Mez says. “Or are there regions of the brain that we’re not looking carefully enough at?”

There still isn’t a way to diagnose CTE during life, and that’s “the 800-pound gorilla in the room,” says neurologist David Brody of Washington University School of Medicine in St. Louis.

Detecting the disease in patients will be crucial for understanding how common CTE is in the NFL, “let alone in the millions of people who participated in college, high school and youth football,” says Rabinovici. “In the meantime, we need to focus on prevention of concussions and other head impacts at all levels of contact sports.”

A round belly, stubby feet and a tapering tail made one armored reptile a lousy swimmer. Despite earlier reports, Eusaurosphargis dalsassoi might not have swum at all, scientists now say.

E. dalsassoi was first identified in 2003. Fossils were found near Monte San Giorgio at the Swiss-Italian border alongside the remains of marine reptiles and fish that lived roughly 240 million years ago. That association led scientists to conclude the creature was aquatic. But a complete skeleton of E. dalsassoi unearthed in 2002 in the Swiss Alps and recently assembled contradicts that idea.
At just under 20 centimeters long, the fossil, probably of a youngster, shows that E. dalsassoi widened at the stomach and slithered forward with stiff elbow and knee joints and spadelike claws. That’s not a swimmer’s build, paleontologist Torsten Scheyer of the University of Zurich and colleagues report June 30 in Scientific Reports.

Armed with rows of small spikes along its back and spear-shaped plates framing its head, sides and tail, the animal resembled today’s girdled lizards. The researchers speculate that this particular E. dalsassoi died on a beach and then got washed into the ocean.

Scientists have traced the sensation of itch to a place you can’t scratch.

The discomfort of a mosquito bite or an allergic reaction activates itch-sensitive nerve cells in the spinal cord. Those neurons talk to a structure near the base of the brain called the parabrachial nucleus, researchers report in the Aug. 18 Science. It’s a region that’s known to receive information about other sensations, such as pain and taste.

The discovery gets researchers one step closer to finding out where itch signals ultimately end up. “The parabrachial nucleus is just the first relay center for [itch signals] going into the brain,” says study coauthor Yan-Gang Sun, a neuroscientist at the Chinese Academy of Sciences in Shanghai.
Understanding the way these signals are processed by the brain could someday provide relief for people with chronic itch, Sun says. While the temporary itchiness of a bug bite is annoying, longer term, “uncontrollable scratching behavior can cause serious skin damage.”

Previous studies have looked at the way an itch registers on the skin or how neurons convey those sensations to the spinal cord. But how those signals travel to the brain has been a trickier question, and this research is a “major step” toward answering it, says Zhou-Feng Chen, director of the Center for the Study of Itch at Washington University School of Medicine in St. Louis.

A network of neurons in the spinal cord wrangles itch signals, previous research suggests. In particular, spinal neurons that make a protein called gastrin-releasing peptide receptor have been shown to be important in itch signaling. But those neurons didn’t link up directly to the parabrachial nucleus, or PBN, Sun’s team found; instead, they talked to other neurons that send messages to the PBN.

When mice were given injections of a drug that induces allergic itching, the rodents showed greater activity in those neurons connecting the spinal cord to the PBN, Sun and colleagues found. In another experiment, the researchers made neurons going to the PBN light-sensitive, and then used light to stop those neurons from sending messages. When those nerve cells were blocked, mice given an itch-triggering drug scratched less.

It’s too soon to say whether itch signals in humans follow the same route — or whether all kinds of itches take the same path. An allergic itch is different from the sort of itch that comes from a light touch, and the two might be handled differently by the brain (SN: 11/22/08, p. 16). And mice, unlike humans, can’t actually describe how itchy they’re feeling. So scientists have to rely on clues like scratching, a reaction to an itch, not a direct measurement of the sensation itself. Which raises the question: If you don’t feel an urge to scratch an itch, is the itch really there at all?

We came. We saw. We earned our 2017 eclipse t-shirts.

For us, the Aug. 21 total solar eclipse was the culmination of weeks — nay, months — of planning the stories you’ve recently seen on Science News. And as the big day finally approached, many members of the Science News staff past and present traveled far and wide to experience the spectacle.

Undeterred by traffic and clouds, and fueled by bottomless fried chicken and moon pies, correspondents made their way to small towns and big cities in the path of totality. For many of us, this was our first total solar eclipse, and it lived up to the hype. Astronomy writer Lisa Grossman wrote from her perch on a mountaintop in Wyoming, “I thought I knew what to expect from my first total solar eclipse. I had no idea.”

Even the crew at the Science News offices in Washington, D.C., got a pretty sweet view of the moon blocking out 81 percent of the sun. And it has inspired many of us to start planning now for the total solar eclipse that will cross the United States in April 2024.

All in all, the 2017 eclipse was unlike anything we’ve seen before, and it’s something we’re not likely to forget. But just in case, the video below showcases some snapshots from our trips to totality and back again.