New archaeology era for shipwrecks discovered in South China Sea

China's manned submersible Shenhai Yongshi (Deep-sea Warrior) placed underwater permanent survey markers at the core areas of two Ming Dynasty-era sunken ships in the South China Sea after conducting preliminary search and image recordings on Saturday, opening a new chapter in China's deep-sea archaeology.

An underwater archaeological investigation formally kicked off on Saturday for the two ships discovered last October in the South China Sea, said China's National Cultural Heritage Administration on Sunday.

The two ships were discovered in October 2022 in the South China Sea at a depth of about 1,500 meters. One site is mainly composed of about 100,000 porcelain relics. Based on a preliminary survey, the ship may have sunk during the Emperor Zhengde period (1506-21) of the Ming Dynasty. 

The other site has a large number of timber  logs, and the ship is believed to have been carrying overseas cargoes to China, dating back to the Emperor Hongzhi period (1488-1505) of the Ming Dynasty.

Archaeologists said the systematic archaeological investigation will last for about a year in three phases. 

The first phase began on Saturday and will last until early June. Manned submersibles will be released to determine the distribution range of the sites for multi-angle and comprehensive data collection and archaeological recording, and to extract specimens of representative cultural relics and samples of the seabed sediment.

The second and third phases are planned to be implemented from August to September in 2023 and from March to April in 2024. After the archaeological surveys, the next step will be proposed on the basis of the sunken ships' status and technical conditions.

The investigation of the two shipwrecks will provide evidence of ancient Chinese people's activity in the South China Sea, making breakthroughs in the study of Chinese maritime history, ceramic history, overseas trade history and the Maritime Silk Road.

China's Shenzhou-16 crew complete first extravehicular activity

Shenzhou-16 crew members Jing Haipeng, Zhu Yangzhu and Gui Haichao successfully completed all the assigned tasks and safely returned to the space research module with the support of the robotic arm after about eight hours of their first extravehicular activity (EVA), the China Manned Space Engineering Office (CMSA) said on Thursday.

During the spacewalk, the astronauts completed tasks including bracket installation and lifting of panorama camera B in the core module and the unlocking and lifting of panorama cameras A and B of the Mengtian lab module.

Jing and Zhu went out for the spacewalk. Zhu has become the first space flight engineer to perform an EVA.

The Shenzhou-16 crew will also carry out a number of space science experiments and conduct multiple EVAs.

The Shenzhou-16 crew is composed of three types of astronauts: commander, flight engineer, and payload expert. They have been in orbit for 51 days since they entered the space station on May 30.

According to the CMSA, the radiation biology exposure experiment is significant for ensuring a healthy long-term stay in orbit for astronauts and promoting China's crewed lunar landing plans.

With the installation of gas cylinders in the electric propulsion system in orbit, this is the first time the "gas exchange" method has been used to complete the replenishment of electric propellants for long-term orbit maintenance of the space station, making its operation more economic and efficient.

The CMSA said the Shenzhou-16 crew are in good condition, and the space station is running stably.

China launched the Shenzhou-16 manned spacecraft on May 30, sending three astronauts to its space station for a five-month mission.

These beetles use surface tension to water-ski

Waterlily beetles (Galerucella nymphaeae) literally fly across water, high speed videography and a bit of mathematical modeling reveals.

The beetles have a combination of hydrophobic hairs that line their legs and hydrophilic claws that grip the surface of water without getting too wet. Prior to “take off,” the insects lift their middle pair of legs. Then, the insects beat their wings extremely fast and fly horizontally across a pool of water. It looks a lot like water-skiing.
In lab tests, waterlily beetles reached 0.5 meters per second — without an active brake system. Surface tension keeps the insects afloat, they found. The insects create ripples in the water, which generates drag at speeds greater than 0.23 meters per second (more drag than when the beetles just fly through air). Thus, for these beetles, skiing across a pond at breakneck speeds costs a lot of energy and requires greater wing thrust than normal flying. However, this mode of getting around could be more advantageous for foraging and help them avoid underwater predators like fish, the researchers speculate March 2 in the Journal of Experimental Biology.

Ancient Assyrians buried their dead with turtles

Ancient Assyrians sent their dead to the afterlife with fearsome companions: turtles. Excavations of a burial pit in southeastern Turkey revealed skeletons of a woman and a child, plus 21 turtles, a team led by archaeologist Rémi Berthon of France’s National Museum of Natural History reports in the February Antiquity.

The burial is part of an Assyrian site called Kavuşan Höyük that dates to between 700 and 300 B.C. The turtle bonanza included shells from one spur-thighed tortoise (Testudo graeca) and three Middle Eastern terrapins (Mauremys caspica), plus bones from 17 Euphrates soft-shelled turtles (Rafetus euphraticus). Butchering marks on the R. euphraticus bones indicate that the turtles may have been eaten in a funerary feast, Berthon and his colleagues write.
Back then, turtles were not a regular meal in Mesopotamia. Turtle bones, however, were thought to ward off evil. The abundance of R. euphraticus turtles, a notoriously aggressive species, in this burial pit suggests the deceased had high social status.

To ancient Assyrians, these ferocious reptiles probably represented eternal life and served as psychopomps — mythical guides to the afterlife, the team writes.

Editor’s Note: This story was updated on 4/15/16 to note that turtles were a rare part of the Mesopotamian diet.

Science’s inconvenient (but interesting) uncertainties

Earth sciences reporter Thomas Sumner recalls seeing the documentary film An Inconvenient Truth when he was in high school. The climate science presented in the movie didn’t surprise him too much — a science-minded student, he had already read about many of the issues. But, he says, the film started a broader dialog about global warming.
“People started caring,” he says, noting that he remembers his own family talking about it (and not always harmoniously) at the time. Revisiting the dramatic predictions made in the film proved an interesting journey for Sumner.
“The main criticism I heard was that the film had watered down the science,” he says. Climate science is amazingly complex, and so is modeling effects of change — from how much sea level might rise to how a warming climate could alter hurricane patterns. Even more striking to Sumner were the sheer number of uncertainties that remain. Those uncertainties are not about whether the climate is changing, but about the details of what such changes will mean for the oceans, the atmosphere and the living things on land — and when the various dominoes might fall. Telling the future is hard, especially about interrelated complex systems, but as Sumner reveals in his story, scientists have made steady progress in the last decade.

Another interesting point is the documentary’s (and Al Gore’s) role in politicizing climate science, which is fair to assume was one of the aims. “Gore was polarizing,” Sumner says. “He created a conversation about global warming, but he also cemented it as a political issue.”

Teeth and gums are neither political nor talked much about. But, as contributing correspondent Laura Beil reports, scientists studying a possible role for gum disease in what ails the body must contend with a slew of uncertainties, not unlike those faced by climate scientists. The bacteria that cause gum disease, some studies find, can travel to the arteries, heart, brain and other sites where they can cause havoc. Not all studies agree, and proving the oral bacteria–disease link beyond a doubt may not yet be within scientists’ grasp. But the fix is relatively simple, even if avoided by many: frequent flossing and regular visits to the dentist.

Keeping things simple was the underlying goal of the team of scientists attempting to build, from scratch, a synthetic organism with the least possible number of genes, as Tina Hesman Saey reports. After many tries, the effort succeeded, but not without first humbling the researchers involved. In the initial attempts, their computer-designed minimal genomes didn’t take. What ultimately worked was putting back some of the unknowns — genes with no known cellular job to do. Only then did the DNA inserted into the shell of a microbial cell yield a synthetic microbe capable of growing and reproducing.

Telling a good story about complex science, whether in a film or in a report on the latest research, requires some simplification. But sometimes the most interesting part lies in the uncertainty.

A weasel has shut down the Large Hadron Collider

CERN’s Large Hadron Collider is in standby mode after a 66-kilovolt/18-kilovolt electrical transformer suffered a short circuit April 29 at 5:30 a.m. Central European Time. The culprit: A small wild animal, believed to be a weasel, gnawing on a power cable.

“The concerned part of the LHC stopped immediately and safely, though some connections were slightly damaged due to an electrical arc,” Arnaud Marsollier, who leads CERN’s press office, wrote in an e-mail to Science News.

Sadly, the weasel did not survive the event, but the LHC should be back online soon. “It may take a few days to repair but such events happened a few times in the past and are part of the life of such a large installation,” Marsollier writes. The power outage comes just as the LHC is preparing to resume collecting data.

This isn’t the the first time an odd event has stalled operations at the particle collider outside Geneva on the Swiss-French border. In 2009, a piece of bread (supposedly a baguette dropped by a bird or from an airplane) interrupted a power installation for an LHC cooling unit.

Heartburn drugs can damage cells that line blood vessels

A popular type of heartburn medicine could hasten wear and tear of blood vessels.

Proton pump inhibitors, or PPIs, gunk up cells that typically line the veins and arteries like a slick coat of Teflon, researchers report May 10 in Circulation Research. Excess cellular junk ages the cells, which could make blood vessels work less smoothly.

The results, though controversial, are the first inkling of evidence that might explain why PPIs have recently been linked to so many different health problems, from heart attacks to dementia.
“The authors present a compelling story,” says Ziyad Al-Aly, a nephrologist at the Veterans Affairs Saint Louis Health Care System in Missouri. It begins to outline how using PPIs could spell trouble later on, he says. But Al-Aly notes that the study has one big limitation: It was done in cells, not people.

Gastroenterologist Ian Forgacs from King’s College Hospital in London agrees. Drawing conclusions about humans from cells grown in the lab requires “a huge leap of faith,” he says. So far, scientists have found only correlations between PPIs and their alleged side effects. “We need to know whether these drugs really do cause dementia and coronary disease and renal disease,” he says.

In the last few decades, proton pump inhibitors have emerged as a kind of wonder drug for heartburn. The drugs switch off molecular machines that pump acid into the stomach. So less acid surges up to burn the esophagus.

In 2012, nearly 8 percent of U.S. adults were taking prescription PPIs, according to a survey published last year in JAMA. (Some PPIs are also available over-the-counter.) Many people use PPIs for longer than they’re supposed to, says study coauthor John Cooke, a cardiologist at Houston Methodist Research Institute in Texas. “These are very powerful drugs­ — they’re not Tums,” he says. “They have side effects.”

Several of these side effects are still under debate. And if PPIs do increase the risk of dementia, say, or kidney disease, no one knows how. So Cooke and colleagues explored what chronic exposure to the drugs, which travel through the bloodstream, does to cells lining the blood vessels.
Human cells treated with a PPI called esomeprazole (sold as Nexium) seemed to age faster than untreated cells, the researchers found. The cells lost their youthful shape and instead “looked kind of like a fried egg,” Cooke says. They also lost the ability to split into new cells, among other signs of aging.

Cooke traced the rapid aging to mishaps in acid-filled cellular chambers called lysosomes. These chambers act as tiny garbage disposals; they get rid of junk like broken-down proteins. But PPIs, which work so well at shutting down acid production in the stomach, also seemed to shut down the acidic garbage disposals, too, the researchers found. That caused proteins to pile up, forming “little heaps of rubbish,” Cooke says.

Mucking with blood vessels’ lining could trigger all sorts of problems. For instance, instead of gliding easily through, platelets and white blood cells could get hung up, sticking to vessel walls like Velcro. “That’s how hardening of the arteries starts,” Cooke says.

The next step is to see if similar damage occurs in people. Doctors and regulatory agencies should take a second look at the widespread use of PPIs, too, Cooke says. “There’s enough data now that we have to be very cautious in our use of these agents.”

But some researchers think PPIs are getting a bum rap. “Everybody and their mother now want to hammer PPIs,” says gastroenterologist David Metz of the University of Pennsylvania. “It’s unfortunate because they’re spectacular drugs and they save people’s lives.”

The real question, Al-Aly says, is whether the benefits outweigh the risks.

Hornbills join toucans in the cool beak club

In the scorching heat of the Kalahari Desert, some birds still manage to keep their cool.

Thermal imaging reveals that the southern yellow-billed hornbill (Tockus leucomelas) vents heat from its beak, a phenomenon previously observed in toco toucans (Ramphastos toco). A team of South African researchers snapped infrared photos of 18 hornbills on a farm in the southern edge of the desert at temperatures from 15° to 45° Celsius.

When air temperatures hit 30.7° Celsius, the difference between beak surface temperature and air temperature spikes — indicating the birds were actively radiating heat through their beaks. At most, the birds lost about 25.1 watts per square meter through their beaks. Hornbills probably manage this cool trick by dilating the blood vessels to increase flow in their uninsulated beaks, the team writes May 18 in PLOS ONE.

Toucans lose about 60 percent of their total heat loss through their beaks, but hornbills only shed up to 20 percent of their heat loss through this method. The researchers chalk that difference up to larger beak-to-body-size in toucans.

Bacteria resistant to last-resort antibiotic appears in U.S.

A last-ditch weapon against drug-resistant bacteria has met its match in Pennsylvania.

A 49-year-old woman has tested positive for a strain of Escherichia coli resistant to the antibiotic colistin, researchers report May 26 in Antimicrobial Agents and Chemotherapy.

It’s the first time in the United States that scientists have found bacteria carrying a gene for colistin resistance known as mrc-1, write study coauthor Patrick McGann of Walter Reed Army Institute of Research in Silver Spring, Md., and colleagues.
But perhaps even more alarming is that the gene rides on a transferable loop of DNA called a plasmid.

“That means we now see a possibility of spread,” says physician and clinical microbiologist Robert Skov. And not just from mother cell to daughter cell, he says, but to neighboring strains of bacteria, too.

Bacteria carry most of their genetic information in a tangle of DNA contained in chromosomes inside the cell. But tiny loops of DNA called plasmids hang around outside of the tangle. These loops carry extra information that bacteria can use, like how to protect themselves from antibiotics. Bacteria can swap plasmids like trading cards, effectively spreading instructions for antibiotic resistance.

In December, Skov and colleagues discovered a Danish patient carrying bacteria with mcr-1 plasmid DNA, like the woman in Pennsylvania. And in November of 2015, researchers reported something similar in China.

Until then, all known colistin resistance was due to tweaks in chromosomal DNA (which, unlike plasmid DNA, isn’t easily spread among bacteria), says Skov, of the Statens Serum Institut in Copenhagen, who was not involved with the new work.

Colistin, a 50-year-old drug that doctors largely stopped prescribing in the 1970s because of its side effects, has made a comeback in the last five to 10 years. It’s used when other antibiotics fail; it’s a treatment option for people infected with multidrug-resistant bacteria. Now, with colistin-resistant bacteria, Skov says, antibiotic treatment options are becoming more and more limited.

The problem, scientists have been pointing out for years, is that people are taking antibiotics too frequently. More use means more opportunity for bacteria to develop resistance.

Still, even with colistin-resistant bacteria emerging all over the world, Skov says he doesn’t expect thousands of people to become infected.

“The scenario now is that once in a while, we’ll see a patient carrying bacteria that we don’t have any good antibiotics left for.” But that, he adds “is dreadful enough.”

Earth has a tiny tagalong, and no, it’s not a moon

Quasisatellite
KWAH-zee-SAT-ah-lite n.
A body that orbits the sun and appears to orbit Earth.

Asteroid 2016 HO3 appears to orbit Earth, but that’s just an illusion. As the space rock loops around the sun, it plays leapfrog with our planet, sometimes speeding ahead sometimes falling behind. The asteroid’s suncentric orbit keeps it from qualifying as a full-fledged moon of Earth, but its constant proximity to us is enough to make it the only known “quasisatellite” of our world.
SUBSCRIBE
This temporary tagalong was discovered on April 27 in images from the Pan-STARRS observatory in Hawaii. The asteroid’s orbit around the sun is similar to Earth’s — one year on 2016 HO3 is just about 16 hours longer than an Earth year. Earth’s gravity keeps the asteroid from wandering; it never strays farther than about 400 million kilometers from Earth and never comes closer than about 14 million kilometers (38 times Earth’s distance to the moon).

The tiny rock — no more than about 100 meters across — has probably tagged along with Earth for about a century, and orbital calculations suggest that it will continue to do so for several centuries to come.