A Chinese experimental team released a video on social media on Tuesday, saying that they successfully verified the synthesis of LK-99 crystal that can be magnetically levitate for the first time, with larger levitated angle than that of the previous sample obtained by a South Korean team, which is expected to realize the true significance of non-contact superconducting magnetic levitation.

The video was released by a team led by Chang Haixin, a professor at the School of Materials Science and Technology of Huazhong University of Science and Technology, with postdoctoral researcher Wu Hao and doctoral student Yang Li.

However, the video  also stated that they have currently only verified the Meissner effect. Although this crystal exhibits diamagnetism, it is relatively weak and does not possess "zero resistance," and its overall behavior is similar to that of a semiconductor curve. The publisher believes that even if LK-99 has superconducting properties, they are only in trace amounts of superconducting impurities, unable to form a continuous superconducting path.

Previously, a research team from South Korea uploaded two papers on arXiv claiming to have discovered the "world's first room-temperature superconducting material," attracting attention from the globe. It is reported that this material is mainly a modified perovskite crystal structure (referred to as LK-99), a type of lead phosphate with copper doping.

However, the team has faced skepticism due to the insufficient experimental data they have currently provided to prove LK-99 is  a superconductor. Multiple research teams worldwide are attempting to synthesize LK-99 to verify the experimental results at the moment.

After the two papers on LK-99 from South Korean scientists were made public, researchers from the School of Materials Science and Engineering at Beihang University and the Shenyang National Research Center for Materials Science also released their relevant research findings.

Researchers Sun Yan and Liu Peitao from the Institute of Metal Research, Chinese Academy of Sciences, stated that they primarily conducted theoretical calculations. According to the computational results, there is a possibility of room-temperature superconductivity using  LK-99. The results also provided some explanations from the perspective of energy bands, but this does not serve as definitive proof.

The research team from Beihang University conducted tests on the synthesized LK-99 and found that its room-temperature resistance is not zero, and no magnetic levitation was observed. The paper states that the material exhibits characteristics similar to a semiconductor rather than a superconductor.

Room-temperature superconductivity would enable long-distance lossless power transmission, leading to a new wave of global infrastructure development in the electricity network. Additionally, breakthroughs are expected in areas such as superconducting magnets, superconducting cables, and superconducting maglev trains, according to  media reports.

The breakthrough in room-temperature and atmospheric pressure superconducting materials would undoubtedly bring about revolutionary changes in various fields, including energy, transportation, computing, and medical diagnostics.

A mite and a virus are in cahoots in an attack on honeybee health.

The parasitic mite Varroa destructor feasts on bees of all ages and reproduces on pupae. As the mite travels through bee colonies, it can spread deformed wing virus, which can cause crippled wings and death in extreme cases. By suppressing a bee’s immunity, the virus may improve a mite’s ability to feed and breed on baby bees, researchers in Italy report March 7 in Proceedings of the National Academy of Sciences.

Mites were more likely to become mothers on Italian honeybee larvae with higher levels of viral infection, the team found. The number of mites that successfully laid eggs soared from 22 percent on bee larvae that developed normally to 40 percent on bees with infections severe enough to cause crippled wings. Still, mite fertility decreased again on bees with very high levels of viral infection. Understanding the complexities of this mite-virus collusion could help explain the factors leading to colony losses and protect honeybees in the future, the researchers say.

The humble tumbleweed — that icon of the American West, blowing across the dusty, dry landscape of every old Western movie — is an immigrant.

And it isn’t a single species, but several. The first known tumbleweed species to arrive in the United States, Salsola tragus, or Russian thistle, is thought to have hitched a ride in a package of flax seed that some Russian immigrants brought with them to South Dakota in 1873. Over the years, other tumbleweed species arrived, including S. australis, which is thought to be a native of Australia or South Africa, though their paths into the country are less well known.

The species all look pretty similar, though despite the name, they don’t all tumble. They are all weeds, and ones that can pose a fire hazard during drought — a flaming ball of dry plant material that can be blown from place to place. It’s such a serious problem that scientists have even suggested importing fungi from Russia to control the plants.

So scientists have incentive to keep track of the tumbleweed invasion. In 2002, researchers reported that there was a new tumbleweed on the scene in California, S. ryanii. The new species was truly new; it combined the 36 chromosomes of S. tragus with the 18 chromosomes of S. australis to form a hybrid species with 54 chromosomes. S. ryanii was an intermediate of its two parents, with traits like fruit size and tumbling behavior falling square in the middle of the two others. And in 2008, scientists predicted that this made it likely that S. ryanii wouldn’t be as much of a problem as its parent species because it wouldn’t be as well adapted to the landscape.

It appears that isn’t the case. Shana Welles, now at the University of Arizona, and Norman Ellstrand of the University of California, Riverside surveyed tumbleweeds at 53 sites across California. In 2002, S. ryanii had been found in just two places in the San Joaquin Valley, but in 2012, the researchers found the plant in nine. In addition, the species also showed up at six other sites, including in coastal areas near San Francisco and Ventura. Clearly, the weed is spreading, Welles and Ellstrand report March 29 in the American Journal of Botany.

“It seems likely that the range of S. ryanii will continue to expand and [the species] is likely to become an important invasive species,” the team writes. It’s now another lookalike invader that can cause problems in the drought-prone West.

It’s even possible that S. ryanii could become an invasive species in other countries, the scientists say, should its seeds find a way to hitchhike across international borders, just like its great-great-great-great-great-grandparents did.

Where it rains, it rumbles. Rainwater and snowmelt help fuel intense earthquakes along a New Zealand tectonic fault, new research suggests.

Tracing the source of water flowing through New Zealand’s Alpine Fault shows that more than 99 percent of it originated from precipitation, researchers report April 19 in Earth and Planetary Science Letters. Scientists knew that underground fluids help trigger quakes, but the origins of these fluids have been uncertain. In this case, the nearby Southern Alps concentrate rainfall and meltwater on top of the Alpine Fault while the fault itself serves as an impermeable dam that traps the water.
The fault “essentially [is] promoting its own large fluid pressures that can lead to earthquakes,” says study coauthor Catriona Menzies, a geologist at the University of Southampton in England. Identifying the fluid source will help scientists better predict the fault’s seismic cycle, she says.

New Zealand sits on the boundary where the Australian and Pacific tectonic plates collide. This collision generates a powerful earthquake along the Alpine Fault around once every 330 years, with the most recent temblor in 1717; it also gradually formed the Southern Alps as the two plates scrunched upward. Moist air condenses on its way up and over the mountains, causing torrential rainfall that typically exceeds 10 meters annually. Menzies and colleagues wondered how much rainwater makes its way to the fault. Fluids within a fault help induce quakes by altering the strength of rock and by counteracting the forces that hold two sides of a fault together (SN: 7/11/15, p. 10).
Water divulges its origins in several ways. The researchers looked at water-deposited minerals in rocks, the relative abundance of helium in nearby hot springs and the various oxygen and hydrogen isotopes that made up the water — all fingerprints of the water’s source. Even though only about 0.02 to 0.05 percent of rainwater makes it to the fault’s depth, the work revealed that more water came from precipitation than from all other sources, such as water released from surrounding rocks and the underlying mantle. The 3-kilometer-tall Southern Alps may even serve as a water tower that boosts water pressure by heightening the stack of groundwater that sits on top of the fault.

While local geography makes the Alpine Fault unique, the new work provides a template for studying fluids in other earthquake-prone areas such as the recently active Japanese fault, says Patrick Fulton, a geophysicist at Texas A&M University in College Station.

Growth hormone mapped — Discovery of the complete chemical structure of the human growth hormone has been reported…. The discovery marks a major advance toward understanding how the powerful growth-promoting substance works and increases the chances for its eventual synthesis in the laboratory…. Some 5,000 fresh human pituitary glands were required to achieve the results.
— Science News, May 21, 1966

Update
In 1979, researchers produced a synthetic human growth hormone in the lab, using bacteria equipped with human hormone genes. Six years later, the synthetic growth hormone was approved for medical use; distribution of growth hormone collected from human pituitary glands had been halted after infected product was linked to Creutzfeldt-Jakob disease, a fatal brain-wasting disorder. Today, doctors use synthetic growth hormone to treat growth hormone deficiency, which can stunt growth in children. Because synthetic growth hormone can build muscle and trim body fat, it is prohibited as a doping agent by many sports organizations.

Nearly 300 pregnant women in the United States show laboratory evidence of Zika virus infection.

The U.S. Centers for Disease Control and Prevention is monitoring 279 pregnant women, including 122 in U.S. territories, the government agency reported at a news conference May 20.

Those numbers are way up compared with previous counts: Last week, the CDC tallied 47 cases in the states and 65 in the territories. The increase reflects a change in reporting, rather than a spike in new cases, said CDC epidemiologist Margaret Honein, who heads the agency’s birth defects branch.

Before today, the CDC report included only pregnant women who had both positive lab test results and either symptoms or pregnancy complications linked to Zika. The new tally includes women without symptoms of infection.

“We’ve learned a lot in the past four months,” Honein said. Scientists have reported that asymptomatic mothers have given birth to Zika-infected babies with microcephaly or other birth defects, she said.

So far, less than a dozen of the 279 U.S. pregnancies have had adverse outcomes, but the agency wouldn’t specify what those outcomes were, or how many women have given birth, miscarried or terminated their pregnancies.

In the United States, Honein said, microcephaly typically affects six per 10,000 infants.

Scientists have found one of the youngest exoplanets ever, huddling close to a star that is just 2 million years old. Located 450 light-years from Earth in the constellation Taurus, the star is so young that it still has its baby fat — it is surrounded by the disk of gas and dust from which it formed.

The planet, CI Tau b, is hefty for an infant — tipping the scales at 11 times the mass of Jupiter, say astronomer Christopher Johns-Krull of Rice University in Houston and colleagues in a paper posted May 25 on arXiv.org. It’s surprising, the researchers say, that such a large planet could have formed in just 2 million years — peanuts on cosmic timescales.
Such baby-faced exoplanets have been spotted before (SN: 12/26/15, p. 14), but they’ve lingered farther from their stars. This fledgling planet shows that such behemoths can form quickly and snuggle close to their stars. Scientists still don’t know whether star-hugging planets form far away and migrate inwards, or whether they are birthed close to their stars. The new planet could shed light on that process.

The scientists used a variety of optical and infrared telescopes to reveal periodic variations in the frequency of the star’s light, caused by the planet’s gravitational pull. CI Tau b tugs its star back and forth as it swings around in a tight orbit that it completes every nine days, the researchers determined. Hints of the planet showed up in both optical and infrared light, ruling out spurious signals caused by sunspots or other variability within the young and active star.

Editor’s note: Science News astronomy writer Christopher Crockett is a coauthor on the paper, which incorporates work he did as an astronomer at Lowell Observatory in Flagstaff, Ariz., prior to joining Science News.

The brains of human ancestors didn’t just grow bigger over evolutionary time. They also amped up their metabolism, demanding more energy for a given volume, a new study suggests.

Those increased energy demands might reflect changes in brain structure and organization as cognitive abilities increased, says physiologist Roger Seymour of the University of Adelaide in Australia, a coauthor of the report, published online August 31 in Royal Society Open Science.

Blood vessels passing through bones leave behind holes in skulls; bigger holes correspond to bigger blood vessels. And since larger vessels carry more blood, scientists can use hole size to estimate blood flow in extinct hominids’ brains. Blood flow in turn indicates how much energy the brain consumed. (In modern humans, the brain eats up 20 to 25 percent of the energy the body generates when at rest.)
Seymour and colleagues focused on the carotid arteries, the vessels that deliver the bulk of the brain’s blood. The team looked at nearly three dozen skulls from 12 hominid species from the last 3 million years, including Australopithecus africanus, Homo neanderthalensis and Homo erectus. In each, the researchers compared the brain’s overall volume with the diameter of the carotid artery’s tiny entrance hole at the base of the skull.
“We expected to find that the rate of blood flow was proportional to the brain size,” Seymour says. “But we found that wasn’t the case.” Instead, bigger brains required more blood flow per unit volume than smaller brains.
The boost in blood flow, and therefore metabolism, suggests two possible conclusions, Seymour says. As hominid brains got bigger, they might have packed in more nerve cells, or their nerve cells might have fired more frequently. Either way, he argues, the increased blood flow suggests greater brainpower, perhaps reflecting reorganization of the brain over the course of evolution.

But not all of the blood coming into the brain through the carotid arteries directly supports mental prowess. “You need more complicated wiring for bigger and more cognitively advanced brains,” says Dean Falk, an evolutionary anthropologist at Florida State University in Tallahassee. “But those brains have more advanced cooling requirements.”

Some of the blood coming in through the carotid arteries absorbs heat generated by the brain’s activity and then drains away, helping to keep the brain cool, Falk says. So while the study is a scientifically rigorous look at metabolism and blood flow toward the brain, she says, a follow-up study is needed to account for the blood moving away from the brain.

Lawrence David’s gut check gets personalA Jim Carrey movie inspired computational biologist Lawrence David to change the course of his research. As a graduate student, David saw Yes Man, a 2008 film in which Carrey’s character is forced to say yes to all propositions.

David thought the movie’s message about opening yourself to new experiences, even uncomfortable ones, might make science more exciting than it already was. “Only good things would happen if I loosened up and said yes to everything,” he says.

The next day, his graduate mentor at MIT, Eric Alm, was talking about the brand-new science of the human microbiome, the collection of bacteria, viruses and other microscopic organisms inhabiting the human body. What someone ought to do, Alm suggested, is sample a person’s feces every day for a year to see whether the microbiome changes. “I had just seen the movie, so I said, ‘Well, I guess I have to say yes now,’ ” David recalls.
David took Alm’s suggestion a step further by chronicling his own microbiome, collecting his feces every day in “plastic hats that look like something the Flying Nun would wear.” He washed his mouth with a chemical solution and spit into a tube to harvest mouth bacteria, popping all the samples into his refrigerator or freezer until he could get them to the lab. He customized an iPhone diary app so he and Alm, who joined the study, could track 349 different health and lifestyle measures, which included the timing and consistency of bowel movements, sleep quality and duration, blood pressure, weight, vitamin use and mood. They noted, in detail, the foods they ate, symptoms of any illnesses and medications used to treat those illnesses. By the end of the year, David had “10,000 measurements of how two people lived their lives.”
David, now 33 and at Duke University, regularly opens himself to new scientific challenges, though they aren’t always quite so personal. Before finishing his degree at MIT, he had already initiated one new field of research and delved into several others outside his expertise.

Awards committees and granting organizations have taken note. David has won the Beckman Young Investigator award and the Searle Scholars award, which support cutting-edge work by young scientists. Fresh out of graduate school, he became a junior fellow at Harvard, where he led his own research.

“He has an ability to see what the problem is and just get it done in the most straightforward way possible,” Alm says.
David spent most of his graduate student years in Alm’s lab writing and running computer code that calculated the ancient birth dates of genes, reproducing the most likely evolutionary histories of gene families and predicting capabilities of ancient microbes. Alone that would have been a nice contribution; many researchers thought untangling those relationships would be too computationally complex, Alm says.

But to get the full picture, David had to expand into other fields, working with geologists and geochemists to determine whether his predictions made sense in light of Earth’s geologic history. In a study that birthed a new field by marrying geochemistry and genetics, he and colleagues discovered that genes encoding oxygen-producing proteins appeared hundreds of thousands of years before oxygen began accumulating in early Earth’s atmosphere (SN Online: 12/21/10). For a study published in Science in 2008, he also delved into ecology, investigating how ocean microbes evolve into separate species without the physical boundaries that would keep them from mixing.

Population flux
The personal microbiome challenge was an unprecedented look at how friendly bacteria change over time and with lifestyle and dietary choices. Long known to play an important role in digestion, the gut microbiome has recently been implicated in health conditions including heart disease, obesity and asthma, and may even influence behavior (SN: 4/2/16, p. 23). Many people have suggested that humans and their microbes are so interdependent, they should be considered composite organisms (SN: 1/11/14, p. 14).

David, Alm and colleagues presented the results of their study in 2014 in Genome Biology. They found that the gut microbiome remains stable for months, but some events, such as travel, illness or changing the fiber content of the diet, can rapidly change the mix of gut microbes. Only a handful of studies have ever been done on this fine of a timescale, Alm says.

A project that would have made others hold their noses “might have been the most enjoyable thing I’ve done in science,” David says. The microbiome analysis relied on computer tools similar to ones he had used as an undergraduate researcher at Columbia University, making it intellectually satisfying.

But the real appeal was how others responded to the work. “People were immediately captivated by the work, and would start to tell me about their own gastrointestinal histories, odd things they had eaten and how that affected the bacteria in their gut,” David says. People sometimes asked his advice on what to eat to keep their gut microbiomes healthy, a question for which he didn’t have a clear answer. “There’s an irony to this,” he says. His voice drops to a whisper as he confesses: “I love junk food…. I shouldn’t be a poster child.”

Hooked on the microbiome, David began studying other people’s bacteria with the help of Peter Turnbaugh, a microbiologist then at Harvard and now at the University of California, San Francisco. By intentionally manipulating people’s diets, the researchers found that it takes only a day for a major dietary change, such as a meat-eater going vegetarian, to shift the composition of gut bacteria. The results, which surprised researchers who had thought such shifts would be more gradual, were reported in Nature in 2013 (SN Online: 12/11/13).

When he arrived at Duke in 2013 to start his own lab, David had a strong track record of developing computational tools to analyze complex datasets, says John Rawls, a microbiome researcher at Duke. But what makes David special isn’t just that he’s a good computer coder. “What sets him apart is his ability to incorporate technology and concepts from engineering into his work,” Rawls says.

Most labs that study the microbiome start with animal studies. But David began with a machine — an artificial gut for growing and manipulating intestinal microbes donated by human volunteers. The contraption consists of multiple growth chambers bristling with plastic tubes. Inside, what David has called “the world’s nastiest slurry” (a fecal sample from a donor) ferments in conditions similar to those in the intestines. One tube feeds into what looks like a dome hair dryer from a beauty salon. That’s a concession to neighboring researchers who complained about the pungent smell.

When graduate student Rachael Bloom joined the lab, David persuaded her to try a completely different way of growing bacteria from feces, designing chips with channels that separate out bacteria into microscopic drops of liquid. In just a few minutes, Bloom can create what are essentially thousands of tiny petri dishes, each with a single bacterium. Neither student nor mentor had any experience with the “microfluidics” technique, but David encouraged Bloom to try, and even be open to failure. “In retrospect, that could be really dangerous,” says Bloom, “but I have learned so much.”

David’s aptitude for engineering shows up at home, too. To keep his two preschool children from getting up too early, David rigged LED lights on a timer. The kids have to wait for the lights to go off before getting out of bed. His wife, a psychiatrist, reinforces the good behavior with a treat.

David says he “tends to be an optimist,” and just assumes his team will find a way over or around any hurdle. “He’s very adventurous. He’s very creative,” says Turnbaugh. “He’s one of the great people in microbiome research who is thinking outside the box and not just following a template.”

David has a simple explanation for why he continues to say yes to projects outside his comfort zone: “I’m easily fascinated.”

A half-century after scientists first introduced a vaccine to combat measles, the disease has been eliminated from a swath of the globe stretching from Canada to Chile — and all the countries in between.

The region is the first in the world to have eliminated the viral disease, the Pan American Health Organization and World Health Organization announced September 27. That’s different from eradication, which means an infectious disease has been scrubbed out permanently, worldwide. So far, only smallpox has been eradicated.

Though measles outbreaks still crop up occasionally in the Americas (this year 54 people have contracted the disease in the United States), they stem from travelers bringing the virus in from other parts of the world. A home-grown outbreak in the Americas hasn’t occurred since a 2002 outbreak in Venezuela.

Because measles still circulates widely elsewhere, vaccination remains crucial, PAHO Director Carissa Etienne noted in a press statement. “Our work on this front is not yet done,” she said. “We cannot become complacent with this achievement but must rather protect it carefully.”