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The world’s known helium reserves just ballooned. Applying gas-finding techniques from the oil industry, scientists uncovered a vast reservoir of more than a trillion liters of helium gas beneath Tanzania. That’s enough to satisfy the world’s helium needs for around seven years, the researchers announced June 28 at the Goldschmidt Conference, a geochemistry meeting being held in in Yokohama, Japan. The find may allay fears that a global helium shortage will hit when the U.S. Federal Helium Reserve — currently the world’s largest helium source — runs dry within the next few years.

While previously known helium reserves were discovered by chance during oil and gas exploration, geologist Diveena Danabalan of Durham University in England and colleagues applied geologic know-how to their helium hunt. Helium accumulates underground during the radioactive decay of unstable elements such as uranium. That helium, though initially trapped, can be liberated when surrounding rock melts during volcanic activity. Using this information as well as seismic imaging of gas-trapping underground formations, the researchers discovered five spots in a volcanic region of Tanzania where water and helium-rich gas bubble to the surface from underground reservoirs.

The researchers predicted that they will be able to find more helium reservoirs and help meet society’s helium needs. Those needs go beyond just making balloons float and voices sound squeaky: Helium is essential for scientific research and a critical component of the cooling systems that allow medical MRI scanners to function.

All systems are go for the Juno spacecraft’s July 4 encounter with Jupiter.

“We couldn’t be more excited about being this close to Jupiter’s doorstep,” said Diane Brown, Juno program executive at NASA Headquarters in Washington, D.C., during a June 30 news briefing.

The scientific instruments have been shut off and the final command sequence for going into orbit around Jupiter has been uploaded to the spacecraft’s computers. On July 4, the probe will fire its main engine for 35 minutes, using it as a brake to slow down and be captured by Jupiter’s gravity. Once in orbit, Juno will spend 20 months figuring out what’s hiding beneath the thick clouds that encase the planet.

Juno has been busy during its final approach. On June 28, it got one more look at Jupiter and three of its moons. And last week Juno monitored changes in interplanetary plasma (see below) as it crossed a magnetic boundary that shields Jupiter from the stream of charged particles blowing from the sun.

Now all scientists can do is wait. “I have mixed emotions,” said mission lead Scott Bolton, a planetary scientist at the Southwest Research Institute in San Antonio. “I’m excited, but I also have tension and nervousness.” Juno has to perform a critical engine burn all on its own while passing through treacherous belts of radiation that encircle the planet. A series of radio tones from the spacecraft will let mission scientists know whether or not it worked.

“Come see us on July 4,” Bolton said.

Any traveler to the Olympics could potentially bring Zika home, but just four countries bear a substantial risk of seeing the virus spread.

Chad, Djibouti, Eritrea and Yemen all have the right ingredients to sustain mosquito-borne transmission, researchers report July 13 in a weekly report of the U.S. Centers for Disease Control and Prevention. Few people typically travel from those countries to places where Zika virus is active, but the Olympics will change that.

To gauge the risk of a single person traveling to Rio de Janeiro for the Olympics, becoming infected and then sparking an outbreak back home, CDC scientist Ardath Grills and colleagues analyzed environmental and population data for 206 countries planning to participate in the Games.

All countries risk importing Zika from Rio, the authors write, but only 19 not currently reporting Zika outbreaks have the susceptible populations and environmental conditions needed to keep local transmission going. And all but Chad, Djibouti, Eritrea and Yemen already have lots of travelers trekking back and forth from Zika-afflicted countries.

For most countries, including the United States, travel to the Olympics doesn’t add much to the risk (SN Online: 6/14/16). (Overall, the number of people planning to travel to the Games — up to an estimated 500,000 — is less than 0.25 percent of the total number of travelers in 2015 to countries with Zika, the researchers estimate.)

The new analysis is based on “worst-case scenarios,” the authors say. It does not change current public health warnings: Pregnant women should steer clear of the Games and people should take steps to avoid spreading the virus via sexual transmission when they return home.

Analyzing a bevy of diverse data, scientists have drawn a new map of the human brain in extreme relief. Their approach demarcated 180 areas in each half of the outer layer of the brain — including 97 regions in each half that haven’t been described before. The high-resolution map will allow scientists to more precisely scrutinize brain regions and see how they change with, for instance, age and disease.

Many previous maps of the brain have been built with just one type of data. The new map, described July 20 in Nature, forms a holistic view of the brain by combining several different types of information. These specs included how areas behaved while doing certain tasks or nothing at all, as well as detailed anatomical data about the shape and thickness of the brain. Using these metrics from 210 healthy people, neuroscientist David Van Essen of Washington University in St. Louis and colleagues found that each hemisphere contains 180 distinct areas (separated by black lines in image). In this view, colors show how tightly linked each area is to other brain areas that handle auditory (red), touch and movement (green) or visual (blue) information.

The discovery of unknown yeasts hiding in lichens from six continents could shake up a basic idea of what makes up a lichen partnership.

For more than a century, biologists have described a lichen as a fungus growing intimately with some microbes (algae and/or cyanobacteria) that harvest solar energy. The fungus is treated as so important that its name serves as the name for the whole lichen.

Biologists have recognized that more than one fungus can show up in lichen close-ups, but their role hasn’t been clear. Now that may be on the brink of changing.
Fifty-two genera of lichens collected from around the world include a second fungus — single cells, called yeasts, of a previously unknown order now christened Cyphobasidiales. Toby Spribille of the University of Graz in Austria and colleagues report the finding online July 21 in Science.
The first example discovered illustrates why these yeasts might turn out to be more than parasites or mere hitchhikers, says study coauthor John McCutcheon of the University of Montana in Missoula. He and Spribille started the research out of curiosity. They wondered how the yellow, toxin-bearing, thready tangles of lichen called Bryoria tortuosa could have the same fungus and the same algal partner — and thus technically be the same species — as the brown, toxin-poor lichen traditionally called B. fremontii. The researchers looked to see which genes were active in each lichen in hopes that some discrepancy could explain the difference in forms. What the researchers found had nothing to do with the alga or previously known fungus. Instead, ample genetic activity of more abundant yeasts in the toxic B. tortuosa turned out to be the most striking disparity.

After five years of work, the research team now has microscope images of yeast cells embedded in the outer layer, or cortex, of B. tortuosa. Gene-activity results suggest that the yeasts could be what’s making the difference between the forms, maybe even synthesizing toxic vulpinic acid. The yeasts turning up across this widespread class of lichens might explain other mysteries, such as why researchers have largely failed to re-create lichen partnerships in the lab.
It’s a bold hypothesis, but lichenologist Robert Lücking of the Botanic Garden and Botanical Museum Berlin-Dahlem takes the idea of yeast partners seriously. “This will be a huge surprise to the lichenological and mycological community,” he says.

Mosquitoes in Miami now appear to be transmitting Zika virus.

Four cases of Zika infection in Florida were probably acquired via the bite of local mosquitoes, the state’s health department announced July 29. These are the first cases of local transmission of the virus in the continental United States.

“Zika is now here,” Tom Frieden, director of U.S. Centers for Disease Control and Prevention, said in a news briefing July 29.

No mosquitoes trapped yet have tested positive for the virus, but officials suspect Aedes aegypti mosquitoes in a several-block area in north Miami are to blame. “Everything we’ve seen so far indicates that this is mosquito-borne transmission,” Frieden said.

Florida’s small cluster of cases does not necessarily foreshadow an epidemic, he said. The four infected people probably were bitten in early July. Since then, Florida has stepped up efforts to stamp out mosquitoes — including going door-to-door to get rid of standing water and spraying insecticides by truck and by people on foot.

“We believe that widespread transmission in the continental U.S. is unlikely,” Frieden said. “But it’s not impossible.”

Two other mosquito-borne diseases, dengue and chikungunya, have spread locally in Florida in the past. But, Frieden said, those diseases generally dead-end after infecting just one person.

From 1863 to 1890, Leopold and Rudolf Blaschka made more than 10,000 sea creatures out of glass. There were anemones with tapered tentacles and pearled undersides, translucent jellyfish trailing the most delicate threads and feather stars more than worthy of their name despite their rigid composition. The intricate invertebrates, crafted by the father-son team at their studio in Dresden, Germany, were shipped across the world to serve as teaching models at universities and museums. In an era before marine surveys and underwater photography, before the rise of scuba diving resorts, the Blaschkas showed the world the wonders of the sea.

Over five dozen of their glass wonders are now on display at the Corning Museum of Glass in “Fragile Legacy.” Though the exhibit opens with glass eyeballs and a piece of jewelry — a nod to the Blaschkas’ pre-invertebrate business — the highlight is a darkened room set up like an aquarium, with sea creatures seemingly floating in blue. There’s a notable absence of museum placards and descriptions. “We really want people to look at the glassiness,” says Marvin Bolt, a curator of the exhibit, before pointing out the “Field Guide to Underwater Models.” The pamphlet contains each animal’s species name, as it was known in 1885 (when Cornell University acquired the pieces, now on loan to Corning) and as it is known today.
The aquarium offers a sense of the Blaschkas’ style, but it’s the room next door that provides the substance. Sketches and watercolors, bottles of colored powders, tweezers, pliers, scoops and wire, along with a demonstration video, give a fuller sense of how the Blaschkas did their work. Equally impressive are the matchboxes filled with kleine augen (“little eyes” in German) and other tiny but uniform component pieces, suggestive of an assembly line approach to handcrafting the final glass forms. A series of case studies explains how conservators stabilized the pieces, and a trailer for a related documentary, also titled Fragile Legacy, highlights the vulnerability, not of the glass, but of the real-world creatures living in warming seas.
There’s one thing you won’t find in this exhibit — the flowers that the Blaschkas are most famous for today, commissioned by Harvard beginning in 1886. But you’ll spot seeds of this later work in the sea animals’ slender stalks and garlands of orbs. As the Blaschkas moved on to new subjects, their artistry evolved from the forms they’d already mastered.

What had two puny arms, lived 90 million years ago and probably chowed down on other dinosaurs? (Hint: It’s not T. rex.)

A new dinosaur discovered in what is now Patagonia had the runty forelimbs of a Tyrannosaurus rex but is no cousin of the giant iconic predator, researchers report July 13 in PLOS ONE.

The new species, Gualicho shinyae, has a close relative in Africa, an analysis of fossils suggests. T. rex’s ancestors, on the other hand, came from Asia.
Gualicho is a “smaller, slimmer, trimmer version of a T. rex,” says study coauthor Peter Makovicky, a paleontologist at the Field Museum in Chicago. It probably weighed about a ton and was longer than a pickup truck.
In 2007, Makovicky’s team discovered Gualicho’s partial skeleton — including those impractical arms. The dinosaur probably caught prey with its huge head, Makovicky says. Though the researchers haven’t dug up a skull yet, tiny arms seem to be a trade-off for a big head. Finding Gualicho’s skull would help nail down that idea, he adds.

Gualicho may have fed on grazers called ornithopods, such as duck-billed dinosaurs. Or perhaps it fed on the long-necked, long-tailed sauropods, which were common in the region. But only the youngsters. Sauropod adults were gigantic, Makovicky says, definitely not prey for a (relatively) little guy like Gualicho.

It’s hard to pin down Stephen Wolfram’s scientific discipline. He is part mathematician, part computer scientist, part physicist. He’s also an inventor and entrepreneur, known for the mathematics software package Mathematica and a variety of other endeavors. And he blogs.

Among his blog posts and other essays and talks are commentaries on the lives of other prominent figures from science and math; some Wolfram knew personally, others he has researched extensively. In his new book Idea Makers, Wolfram has collected accounts of 16 such people, discussing their work and its meaning for the nature of science and the process of understanding math, computing and the physical world. Each entry provides a healthy dose of personal information as well.
Some of the people Wolfram discusses are widely known — Richard Feynman and Steve Jobs, for example. Others are relatively obscure, such as Russell Towle and Richard Crandall. But all have captivated Wolfram’s interest, either by way of friendship or their historical importance for the fields of study that Wolfram himself has contributed to.

On the historical side, Wolfram offers his views of the logician Kurt Gödel, computer scientist (perhaps the original computer scientist) Alan Turing and mathematicians John von Neumann and George Boole. Wolfram provides an especially extensive discussion of Ada Lovelace and her interactions with Charles Babbage as they contemplated the prospect of powerful computing engines a century ahead of their time.

Wolfram also dives into the story of Srinivasa Ramanujan, and the lessons his genius offers about the nature of math. With little formal training, Ramanujan discovered many surprising results that seemed at first glance to be a bunch of “random facts of mathematics.” But in recent decades, many have been linked to deep mathematical principles that he seems to have somehow perceived without knowing it. How did he do it? Wolfram suspects that he “had intuition and aesthetic criteria that in some sense captured some of the deeper principles we now know, even if he couldn’t express them directly.”

Personal style, whether as reflected in the subtle genius of Ramanujan or the boldness of vision-driven Jobs, plays an underappreciated role in the progress of science and technology. Wolfram has collected some illuminating examples of the ways the human side of scientific thinkers can enrich the work they do.

Zika may harm grown-up brains.

The virus, which can cause brain damage in infants infected in the womb, kills stem cells and stunts their numbers in the brains of adult mice, researchers report August 18 in Cell Stem Cell. Though scientists have considered Zika primarily a threat to unborn babies, the new findings suggest that the virus may cause unknown — and potentially long-term — damage to adults as well.

In adults, Zika has been linked to Guillain-Barré syndrome, a rare neurological disorder (SN: 4/2/16, p. 29). But for most people, infection is typically mild: a headache, fever and rash lasting up to a week, or no symptoms at all. In pregnant women, though, the virus can lodge in the brain of a fetus and kill off newly developing cells (SN: 4/13/16).
If Zika targets newborn brain cells, adults may be at risk, too, reasoned neuroscientist Joseph Gleeson of Rockefeller University in New York City and colleagues. Parts of the forebrain and the hippocampus, which plays a crucial role in learning and memory, continue to generate nerve cells in adult brains.

In mice infected with Zika, the virus hit these brain regions hard. Nerve cells died and the regions generated one-fifth to one-half as many new cells compared with those of uninfected mice. The results might not translate to humans; the mice were genetically engineered to have weak immune systems, making them susceptible to Zika.

But Zika could potentially harm immunocompromised people and perhaps even healthy people in a similar way, the authors write.