Volkswagen's announcement that no evidence of forced labor was found in its supply chain in Northwest China's Xinjiang Uygur Autonomous Region not only refutes lie spun by some anti-China forces in the West, it also reflects an intensified tussle between European business and political circles, as the latter politicizing human rights issues runs counter to market rules and European companies' interests, said Chinese experts. They also warned Europe against following the US in weaponizing claims of "forced labor," as such move will hurt Europe's interests more than the US.

The audit on Volkswagen's jointly owned plant in Xinjiang was carried by Loening Human Rights & Responsible Business GmbH, among the site's 197 employees in SAIC-Volkswagen (Xinjiang) Automotive Co.

The audit encompassed on-site document checks in Urumqi city as well as interviews with staff and executives of the legal entity in Xinjiang. Several on-site inspections, including walkabouts of the outdoor premises of the plant were also part of the auditing process.

As of November 1, 2023, the legal entity had 197 employees, of which 150 employees are of Han ethnicity, accounting for 76.1 percent, and 23.9 percent of employees are ethnic minorities including Uygurs.

Loening said that the employees are qualified, having worked for the company for a long time of up to 10 years, have a low work intensity and are being remunerated above the average in the region. Overtime work is next to non-existent.

There were no indications of any use of forced labor among the employees at the plant, it said.

The result serves as a strong rebuttal to certain Western countries' smear campaign hyping the claims of "forced labor" in Xinjiang, as the audit process was conducted independently, in accordance with US and European standard and in line with the truth, a professor specializing in human rights issues at Southwest University of Political Science and Law, who requested anonymity, told the Global Times.

Earlier this year, Volkswagen investors demanded that the carmaker request cooperation from SAIC to conduct an independent audit of labor conditions at the site in Xinjiang, Reuters reported. Volkswagen's China chief Ralf Brandstaetter said there was no evidence of human rights violations or forced labor when he toured the site in February.

Big German companies, such as Volkswagen, have become targets of blame by some forces in Europe over human rights issues in China, because Germany has the closest trade cooperation with China within the EU, said Cui Hongjian, a professor with the Academy of Regional and Global Governance with Beijing Foreign Studies University. He said that those forces intend to use big corporations to pressure Germany and they believe once Germany changes its stance on China, it would help form a tougher stance against China within the EU.

Cui noted that the Volkswagen case has proved that the tendency in EU using political issues to poison cooperation has repulsed the European business circle. Big European companies now find the judicial and legal environment they thrived on has been eroded by certain China hawks in the EU, noting that cases such as forcing companies to prove their innocence will be repeated as long as some in Europe still see China as a threat.

In September 2022, the European Parliament proposed a regulation to ban products made using forced labor, including child labor, in the European Union (EU) internal market. However, the regulation has stalled, as member states struggle to agree on a common position that would allow inter-institutional negotiations to begin.

Part of the rationale behind Europe's "forced labor" move is to push for supply chain reconstruction, which might run against market rules as well as companies' interests, said Yan Shaohua, a research associate professor at the Center for China-Europe Relations, Fudan University. He noted that Volkswagen's example mirrors a tussle between business and political circles in Europe and helps to clear some misperceptions toward Xinjiang in Europe.

Dispel misunderstanding

"Forced labor" topic has been frequently abused by Western countries, especially the US, to pressure foreign companies who do business with China and Chinese companies. Similar to Volkswagen, US shoe company Skechers had a batch of its products manufactured in China seized by US customs, citing the so-called Uyghur Forced Labor Prevention Act, the Global Times learned from sources in 2022.

In order to meet the demand of the US customs, Skechers organized an independent investigation conducted by a third party, which found no evidence to support the "forced labor" allegations.

In September, US Department of Homeland Security said in a statement that it added three Chinese companies - Xinjiang Tianmian Foundation Textile Co Ltd, Xinjiang Tianshan Wool Textile Co. Ltd, and Xinjiang Zhongtai Group Co. Ltd - to the Uyghur Forced Labor Prevention Act (UFLPA) Entity List for their business practices involving "persecuted" minorities in Xinjiang, media reported.

In response, Chinese Foreign Ministry spokesperson Wang Wenbin said that China has made clear time and again that the allegations of "forced labor" in Xinjiang are nothing but an enormous lie propagated by people against China to smear our country's image.

Washington is determined to spin "forced labor" lie in order to strip China from the global supply chain, as Xinjiang remains a relatively small market for the US. However, Xinjiang's market is much more important for Europe, thus if Europe follows the US to weaponize "forced labor" claims, European companies and its economy will feel the pinch, Cui said.

In 2021, Xinjiang recorded around 261.8 billion yuan ($41 billion) in foreign trade with EU countries in the first 11 months of the year, up 30 percent year-on-year.

As agreed between China and the EU, the 24th China-EU Summit will be held in Beijing on Thursday, Foreign Ministry spokesperson Hua Chunying announced on Monday.

Wang Yiwei, director of the Institute of International Affairs at the Renmin University of China said that as usual, human rights issue will be discussed between the two sides. "The Volkswagen case has proved that the reckless smearing of China and politicians' thwarting of China-Europe cooperation out of ideological prejudice has provoked antipathy among Europe's business communities, while the public is eager to get a more rational and objective picture of China."

The Vietnamese version of China's hit reality show Sisters Who Make Waves has recently been released on the country's national television platform VTV3 and sites like YouTube. The show is crowded with Vietnam's hottest celebrities and has become highly popular, attracting a wide range of local viewers. The original show made a similar splash in the Chinese entertainment market when it was first released in 2020.

The Chinese version included stars like Zhang Yuqi, who has gained over 13 million viewers on China's Sina Weibo, and the Vietnamese show is star-studded as well. 53-year-old Vietnamese singer Hồng Nhung has joined the show, along with actress Ninh Dương Lan Ngọc and model H'Hen Niê.

Wanghe Minjun, a TV industry expert, told the Global Times that celebrities on the show need to be successful women, but also need to have contrasting personalities.

"Like all reality shows, the program needs tension and something that can spur discussion," said the expert, such as "a woman who has been to red carpet events many times but still remains childish in everyday life."

The show has become popular on YouTube, with an episode released two weeks ago having been viewed by 4.97 million viewers.

"A singer can connect with listeners' emotions through her voice. Listening to Hồng Nhung is like watching a movie unfold in my mind. I'm impressed that her skill is increasing as she gets older," a Vietnamese netizen said in a post on YouTube.

Xu Shuming, a cultural sociologist, told the Global Times that Sisters Who Make Waves is actually an "encouraging show that gives the audience an image of modern women's potential in the social sphere."

"Compared to shows about young idols, ones about mature and successful women can be more eye-catching since they can draw the attention of a larger group of people," Xu told the Global Times.

Vietnamese actress and singer Chi Pu joined the original Chinese show for its 2023 season and became widely popular with domestic viewers.

Her appearance on the show reassured the international market about the "universal acceptance of the subject of women's power," Wanghe told the Global Times. Chi Pu's Chinese journey was also significant for the later Vietnamese adaptation.

The original Chinese version is available on China's video platform Mango TV, which collaborated with Vietnamese platforms VTV3 and YeaH1 Group, as well as production company STV Production.

"With the advantages of multiple platforms and a large audience, we are confident in creating a reality show that will be successful in the Vietnamese entertainment market in 2023," Le Phuong Thao, the chief investment representative of YeaH1 Group, told the media.

So far, the Vietnamese version of Sisters Who Make Waves has attracted a total of 33 sponsors, the highest ever for a Vietnamese reality TV show.

The show's international success also indicates that the burgeoning Chinese entertainment industry is able to produce cultural IP of a "global standard," Wanghe said.

Other Chinese reality shows like Street Dance of China and Our Songs, a singing program, have also been adapted into Vietnamese and Spanish versions. The singing program Super Vocal has also been brought to audiences in North America.

"Chinese IP is good not only because of the shows' creativity, but also the growing Chinese entertainment industry. Its scale has convinced many international insiders," Wanghe told the Global Times.

New observations of the whirling cores of dead stars have deepened the mystery behind a glut of antimatter particles raining down on Earth from space.

The particles are antielectrons, also known as positrons, and could be a sign of dark matter — the exotic and unidentified culprit that makes up the bulk of the universe’s mass. But more mundane explanations are also plausible: Positrons might be spewed from nearby pulsars, the spinning remnants of exploded stars, for example. But researchers with the High-Altitude Water Cherenkov Observatory, or HAWC, now have called the pulsar hypothesis into question in a paper published in the Nov. 17 Science.

Although the new observations don’t directly support the dark matter explanation, “if you have a few alternatives and cast doubt on one of them, then the other becomes more likely,” says HAWC scientist Jordan Goodman of the University of Maryland in College Park.

Earth is constantly bathed in cosmic rays, particles from space that include protons, atomic nuclei, electrons and positrons. Several experiments designed to detect the showers of spacefaring particles have found more high-energy positrons than expected (SN: 5/4/13, p. 14), and astrophysicists have debated the excess positrons’ source ever since. Dark matter particles annihilating one another could theoretically produce pairs of electrons and positrons, but so can other sources, such as pulsars.
It was uncertain, though, whether pulsars’ positrons would make it to Earth in numbers significant enough to explain the excess. HAWC researchers tested how positrons travel through space by measuring gamma rays, or high-energy light, from two nearby pulsars — Geminga and Monogem — around 900 light-years away. Those gamma rays are produced when energetic positrons and electrons slam into low-energy light particles, producing higher-energy radiation.
The size and intensity of the resulting gamma-ray glow indicated that the positrons slowly dissipated away from their pulsar birthplaces, getting bogged down by magnetic fields that permeate the galaxy and twist up the particles’ trajectories. That sluggish departure suggests the particles wouldn’t have made it all the way to Earth, the researchers conclude, and therefore couldn’t explain the excess.

Astrophysicist Dan Hooper of Fermilab in Batavia, Ill., disagrees. He still thinks pulsars are the best explanation for the rogue antimatter. The gamma ray measurements are just one method for studying how cosmic ray particles propagate through space. Other methods indicate that the pulsars’ positrons should be able to make the trek across the galaxy swiftly enough to get to Earth, he says. “I have every confidence that those particles are now reaching the solar system.”

Ruling out pulsars still wouldn’t point the finger at dark matter. “I think they’ve made a good case that these pulsars are not the source,” says astrophysicist Gregory Tarlé of the University of Michigan in Ann Arbor. Instead, Tarlé thinks that scientists can explain the excess positrons by better understanding what happens as cosmic ray particles travel through space. Protons interacting with the interstellar medium — particles that permeate the spaces between stars — could produce positrons that would explain the observations, without invoking either dark matter or pulsars.

The conflict leaves physicists with their work cut out for them. “In order to prove that it’s dark matter, you have to prove that it’s not something ordinary,” says HAWC researcher Brenda Dingus of Los Alamos National Laboratory in New Mexico. Although the new result disfavors the most obvious ordinary candidates, Dingus says, other possibilities are still in the running. “We need to look harder.”

Like sailors and spelunkers, physicists know the power of a sturdy knot.

Some physicists have tied their hopes for a new generation of data storage to minuscule knotlike structures called skyrmions, which can form in magnetic materials. Incredibly tiny and tough to undo, magnetic skyrmions could help feed humankind’s hunger for ever-smaller electronics.

On traditional hard drives, the magnetic regions that store data are about 10 times as large as the smallest skyrmions. Ranging from a nanometer to hundreds of nanometers in diameter, skyrmions “are probably the smallest magnetic systems … that can be imagined or that can be realized in nature,” says physicist Vincent Cros of Unité Mixte de Physique CNRS/Thales in Palaiseau, France.
What’s more, skyrmions can easily move through a material, pushed along by an electric current. The magnetic knots’ nimble nature suggests that skyrmions storing data in a computer could be shuttled to a sensor that would read off the information as the skyrmions pass by. In contrast, traditional hard drives read and write data by moving a mechanical arm to the appropriate region on a spinning platter (SN: 10/19/13, p. 28). Those moving parts tend to be fragile, and the task slows down data recall. Scientists hope that skyrmions could one day make for more durable, faster, tinier gadgets.

One thing, however, has held skyrmions back: Until recently, they could be created and controlled only in the frigid cold. When solid-state physicist Christian Pfleiderer and colleagues first reported the detection of magnetic skyrmions, in Science in 2009, the knots were impractical to work with, requiring very low temperatures of about 30 kelvins (–243° Celsius). Those are “conditions where you’d say, ‘This is of no use for anybody,’ ” says Pfleiderer of the Technical University of Munich.

Skyrmions have finally come out of the cold, though they are finicky and difficult to control. Now, scientists are on the cusp of working out the kinks to create thawed-out skyrmions with all the desired characteristics. At the same time, researchers are chasing after new kinds of skyrmions, which may be an even better fit for data storage. The skyrmion field, Pfleiderer says, has “started to develop its own life.”
In a magnetic material, such as iron, each atom acts like a tiny bar magnet with its own north and south poles. This magnetization arises from spin, a quantum property of the atom’s electrons. In a ferromagnet, a standard magnet like the one holding up the grocery list on your refrigerator, the atoms’ magnetic poles point in the same direction (SN Online: 5/14/12).

Skyrmions, which dwell within such magnetic habitats, are composed of groups of atoms with their magnetic poles oriented in whorls. Those spirals of magnetization disrupt the otherwise orderly alignment of atoms in the magnet, like a cowlick in freshly combed hair. Within a skyrmion, the direction of the atoms’ poles twists until the magnetization in the center points in the opposite direction of the magnetization outside. That twisting is difficult to undo, like a strong knot (SN Online: 10/31/08). So skyrmions won’t spontaneously disappear — a plus for long-term data storage.

Using knots of various kinds to store information has a long history. Ancient Incas used khipu, a system of knotted cord, to keep records or send messages (SN Online: 5/8/17). In a more modern example, Pfleiderer says, “if you don’t want to forget something then you put a knot in your handkerchief.” Skyrmions could continue that tradition.
On the right track
Skyrmions are a type of “quasiparticle,” a disturbance within a material that behaves like a single particle, despite being a collective of many individual particles. Although skyrmions are made up of atoms, which remain stationary within the material, skyrmions can move around like a true particle, by sliding from one group of atoms to another. “The magnetism just twists around, and thus the skyrmion travels,” says condensed matter physicist Kirsten von Bergmann of the University of Hamburg.

In fact, skyrmions were first proposed in the context of particles. British physicist Tony Skyrme, who lends his name to the knots, suggested about 60 years ago that particles such as neutrons and protons could be thought of as a kind of knot. In the late 1980s, physicists realized the math that supported Skyrme’s idea could also represent knots in the magnetization of solid materials.

Such skyrmions could be used in futuristic data storage schemes, researchers later proposed. A chain of skyrmions could encode bits within a computer, with the presence of a skyrmion representing 1 and the absence representing 0.

In particular, skyrmions might be ideal for what are known as “racetrack” memories, Cros and colleagues proposed in Nature Nanotechnology in 2013. In racetrack devices, information-holding skyrmions would speed along a magnetic nanoribbon, like cars on the Indianapolis Motor Speedway.

Solid-state physicist Stuart Parkin proposed a first version of the racetrack concept years earlier. In a 2008 paper in Science, Parkin and colleagues demonstrated the beginnings of a racetrack memory based not on skyrmions, but on magnetic features called domain walls, which separate regions with different directions of magnetization in a material. Those domain walls could be pushed along the track using electric currents to a sensor that would read out the data encoded within. To maximize the available space, the racetrack could loop straight up and back down (like a wild Mario Kart ride), allowing for 3-D memory that could pack in more data than a flat chip.
“When I first proposed [racetrack memories] many years ago, I think people were very skeptical,” says Parkin, now at the Max Planck Institute of Microstructure Physics in Halle, Germany. Today, the idea — with and without skyrmions — has caught on. Racetrack memories are being tested in laboratories, though the technology is not yet available in computers.

To make such a system work with skyrmions, scientists need to make the knots easier to wrangle at room temperature. For skyrmion-based racetrack memories to compete with current technologies, skyrmions must be small and move quickly and easily through a material. And they should be easy to create and destroy, using something simple like an electric current. Those are lofty demands: A step forward on one requirement sometimes leads to a step backward on the others. But scientists are drawing closer to reining in the magnetic marvels.

Heating up
Those first magnetic skyrmions found by Pfleiderer and colleagues appeared spontaneously in crystals with asymmetric structures that induce a twist between neighboring atoms. Only certain materials have that skyrmion-friendly asymmetric structure, limiting the possibilities for studying the quasiparticles or coaxing them to form under warmer conditions.

Soon, physicists developed a way to artificially create an asymmetric structure by depositing material in thin layers. Interactions between atoms in different layers can induce a twist in the atoms’ orientations. “Now, we can suddenly use ordinary magnetic materials, combine them in a clever way with other materials, and make them work at room temperature,” says materials scientist Axel Hoffmann of Argonne National Laboratory in Illinois.

Scientists produced such thin film skyrmions for the first time in a one-atom-thick layer of iron on top of iridium, but temperatures were still very low. Reported in Nature Physics in 2011, those thin film skyrmions required a chilly 11 kelvins (–262° C). That’s because the thin film of iron loses its magnetic properties above a certain temperature, says von Bergmann, who coauthored the study, along with nanoscientist Roland Wiesendanger of the University of Hamburg and colleagues. But thicker films can stay magnetic at higher temperatures. And so, “one important step was to increase the amount of magnetic material,” von Bergmann says.

To go thicker, scientists began stacking sheets of various magnetic and nonmagnetic materials, like a club sandwich with repeating layers of meat, cheese and bread. Stacking multiple layers of iridium, platinum and cobalt, Cros and colleagues created the first room-temperature skyrmions smaller than 100 nanometers, the researchers reported in May 2016 in Nature Nanotechnology.

By adjusting the types of materials, the number of layers and their thicknesses, scientists can fashion designer skyrmions with desirable properties. When condensed matter physicist Christos Panagopoulos of Nanyang Technological University in Singapore and colleagues fiddled with the composition of layers of iridium, iron, cobalt and platinum, a variety of skyrmions swirled into existence. The resulting knots came in different sizes, and some were more stable than others, the researchers reported in Nature Materials in September 2017.

Although scientists now know how to make room-temperature skyrmions, the heat-tolerant swirls, tens to hundreds of nanometers in diameter, tend to be too big to be very useful. “If we want to compete with current state-of-the-art technology, we have to go for skyrmionic objects [that] are much smaller in size than 100 nanometers,” Wiesendanger says. The aim is to bring warmed-up skyrmions down to a few nanometers.
As some try to shrink room-temp skyrmions down, others are bringing them up to speed, to make for fast reading and writing of data. In a study reported in Nature Materials in 2016, skyrmions at room temperature reached top speeds of 100 meters per second (about 220 miles per hour). Fittingly, that’s right around the fastest speed NASCAR drivers achieve. The result showed that a skyrmion racetrack might actually work, says study coauthor Mathias Kläui, a condensed matter physicist at Johannes Gutenberg University Mainz in Germany. “Fundamentally, it’s feasible at room temperature.” But to compete against domain walls, which can reach speeds of over 700 m/s, skyrmions still need to hit the gas.

Despite progress, there are a few more challenges to work out. One possible issue: A skyrmion’s swirling pattern makes it behave like a rotating object. “When you have a rotating object moving, it may not want to move in a straight line,” Hoffmann says. “If you’re a bad golf player, you know this.” Skyrmions don’t move in the same direction as an electric current, but at an angle to it. On the racetrack, skyrmions might hit a wall instead of staying in their lanes. Now, researchers are seeking new kinds of skyrmions that stay on track.

A new twist
Just as there’s more than one way to tie a knot, there are several different types of skyrmions, formed with various shapes of magnetic twists. The two best known types are Bloch and Néel. Bloch skyrmions are found in the thick, asymmetric crystals in which skyrmions were first detected, and Néel skyrmions tend to show up in thin films.

“The type of skyrmions you get is related to the crystal structure of the materials,” says physical chemist Claudia Felser of the Max Planck Institute for Chemical Physics of Solids in Dresden, Germany. Felser studies Heusler compounds, materials that have unusual properties particularly useful for manipulating magnetism. Felser, Parkin and colleagues detected a new kind of skyrmion, an antiskyrmion, in a thin layer of such a material. They reported the find in August 2017 in Nature.

Antiskyrmions might avoid some of the pitfalls that their relatives face, Parkin says. “Potentially, they can move in straight lines with currents, rather than moving to the side.” Such straight-shooting skyrmions may be better suited for racetrack schemes. And the observed antiskyrmions are stable at a wide range of temperatures, including room temperature. Antiskyrmions also might be able to shrink down smaller than other kinds of skyrmions.

Physicists are now on the hunt for skyrmions within a different realm: antiferromagnetic materials. Unlike in ferromagnetic materials — in which atoms all align their poles — in antiferromagnets, atoms’ poles point in alternating directions. If one atom points up, its neighbor points down. Like antiskyrmions, antiferromagnetic skyrmions wouldn’t zip off at an angle to an electric current, so they should be easier to control. Antiferromagnetic skyrmions might also move faster, Kläui says.

Materials scientists still need to find an antiferromagnetic material with the necessary properties to form skyrmions, Kläui says. “I would expect that this would be realized in the next couple of years.”

Finding the knots’ niche
Once skyrmions behave as desired, creating a racetrack memory with them is an obvious next step. “It is a technology that combines the best of multiple worlds,” Kläui says — stability, easily accessible data and low energy requirements. But Kläui and others acknowledge the hurdles ahead for skyrmion racetrack memories. It will be difficult, these researchers say, to beat traditional magnetic hard drives — not to mention the flash memories available in newer computers — on storage density, speed and cost simultaneously.

“The racetrack idea, I’m skeptical about,” Hoffmann says. Instead, skyrmions might be useful in devices meant for performing calculations. Because only a small electric current is required to move skyrmions around, such devices might be used to create energy-efficient computer processors.

Another idea is to use skyrmions for biologically inspired computers, which attempt to mimic the human brain (SN: 9/6/14, p. 10). Brains consume about as much power as a lightbulb, yet can perform calculations that computers still can’t match, thanks to large interconnected networks of nerve cells. Skyrmions could help scientists achieve this kind of computation in the lab, without sapping much power.
A single skyrmion could behave like a nerve cell , or neuron, electrical engineer Sai Li of Beihang University in Beijing and colleagues suggest. In the human body, a neuron can add up signals from its neighbors, gradually building up a voltage across its membrane. When that voltage reaches a certain threshold, ions begin shifting across the membrane in waves, generating an electric pulse. Skyrmions could imitate this behavior: An electric current would push a skyrmion along a track, with the distance traveled acting as an analog for the neuron’s increasing voltage. A skyrmion reaching a detector at the end would be equivalent to a firing neuron, the researchers proposed in July 2017 in Nanotechnology .
By combining a large number of neuron-imitating skyrmions, the thinking goes, scientists could create a computer that operates something like a brain.

Additional ideas for how to use the magnetic whirls keep cropping up. “It’s still a growing field,” von Bergmann says. “There are several new ideas ahead.”

Whether or not skyrmions end up in future gadgets, the swirls are part of a burgeoning electronics ecosystem. Ever since electricity was discovered, researchers have focused on the motion of electric charges. But physicists are now fashioning a new parallel system called spintronics — of which skyrmions are a part — based on the motion of electron spin, that property that makes atoms magnetic (SN Online: 9/26/17). By studying skyrmions, researchers are expanding their understanding of how spins move through materials.

Like a kindergartner fumbling with shoelaces, studying how to tie spins up in knots is a learning process.

Dying, it turns out, is not like flipping a switch. Genes keep working for a while after a person dies, and scientists have used that activity in the lab to pinpoint time of death to within about nine minutes.

During the first 24 hours after death, genetic changes kick in across various human tissues, creating patterns of activity that can be used to roughly predict when someone died, researchers report February 13 in Nature Communications.
“This is really cool, just from a biological discovery standpoint,” says microbial ecologist Jennifer DeBruyn of the University of Tennessee in Knoxville who was not part of the study. “What do our cells do after we die, and what actually is death?”

What has become clear is that death isn’t the immediate end for genes. Some mouse and zebrafish genes remain active for up to four days after the animals die, scientists reported in 2017 in Open Biology.
In the new work, researchers examined changes in DNA’s chemical cousin, RNA. “There’s been a dogma that RNA is a weak, unstable molecule,” says Tom Gilbert, a geneticist at the Natural History Museum of Denmark in Copenhagen who has studied postmortem genetics. “So people always assumed that DNA might survive after death, but RNA would be gone.”
But recent research has found that RNA can be surprisingly stable, and some genes in our DNA even continue to be transcribed, or written, into RNA after we die, Gilbert says. “It’s not like you need a brain for gene expression,” he says. Molecular processes can continue until the necessary enzymes and chemical components run out.

“It’s no different than if you’re cooking a pasta and it’s boiling — if you turn the cooker off, it’s still going to bubble away, just at a slower and slower rate,” he says.

No one knows exactly how long a human’s molecular pot might keep bubbling, but geneticist and study leader Roderic Guigó of the Centre for Genomic Regulation in Barcelona says his team’s work may help toward figuring that out. “I think it’s an interesting question,” he says. “When does everything stop?”

Tissues from the dead are frequently used in genetic research, and Guigó and his colleagues had initially set out to learn how genetic activity, or gene expression, compares in dead and living tissues.

The researchers analyzed gene activity and degradation in 36 different kinds of human tissue, such as the brain, skin and lungs. Tissue samples were collected from more than 500 donors who had been dead for up to 29 hours. Postmortem gene activity varied in each tissue, the scientists found, and they used a computer to search for patterns in this activity. Just four tissues, taken together, could give a reliable time of death: subcutaneous fat, lung, thyroid and skin exposed to the sun.

Based on those results, the team developed an algorithm that a medical examiner might one day use to determine time of death. Using tissues in the lab, the algorithm could estimate the time of death to within about nine minutes, performing best during the first few hours after death, DeBruyn says.

For medical examiners, real-world conditions might not allow for such accuracy.

Traditionally, medical examiners use body temperature and physical signs such as rigor mortis to determine time of death. But scientists including DeBruyn are also starting to look at timing death using changes in the microbial community during decomposition (SN Online: 7/22/15).

These approaches — tracking microbial communities and gene activity — are “definitely complementary,” DeBruyn says. In the first 24 hours after death, bacteria, unlike genes, haven’t changed much, so a person’s genetic activity may be more useful for zeroing in on how long ago he or she died during that time frame. At longer time scales, microbes may work better.

“The biggest challenge is nailing down variability,” DeBruyn says. Everything from the temperature where a body is found to the deceased’s age could potentially affect how many and which genes are active after death. So scientists will have to do more experiments to account for these factors before the new method can be widely used.

Knocking back an enzyme swept mouse brains clean of protein globs that are a sign of Alzheimer’s disease. Reducing the enzyme is known to keep these nerve-damaging plaques from forming. But the disappearance of existing plaques was unexpected, researchers report online February 14 in the Journal of Experimental Medicine.

The brains of mice engineered to develop Alzheimer’s disease were riddled with these plaques, clumps of amyloid-beta protein fragments, by the time the animals were 10 months old. But the brains of 10-month-old Alzheimer’s mice that had a severely reduced amount of an enzyme called BACE1 were essentially clear of new and old plaques.
Studies rarely demonstrate the removal of existing plaques, says neuroscientist John Cirrito of Washington University in St. Louis who was not involved in the study. “It suggests there is something special about BACE1,” he says, but exactly what that might be remains unclear.

Story continues below graphic
One theory to how Alzheimer’s develops is called the amyloid cascade hypothesis. Accumulation of globs of A-beta protein bits, the idea goes, drives the nerve cell loss and dementia seen in the disease, which an estimated 5.5 million Americans had in 2017. If the theory is right, then targeting the BACE1 enzyme, which cuts up another protein to make A-beta, may help patients.
BACE1 was discovered about 20 years ago. Initial studies turned off the gene that makes BACE1 in mice for their entire lives, and those animals produced almost no A-beta. In humans, however, any drug that combats Alzheimer’s by going after the enzyme would be given to adults. So Riqiang Yan, one of the discoverers of BACE1 and a neuroscientist at the Cleveland Clinic, and colleagues set out to learn what happens when mice who start life with normal amounts of BACE1 lose much of the enzyme later on.

The researchers studied mice engineered to develop plaques in their brains when the animals are about 10 weeks old. Some of these mice were also engineered so that levels of the BACE1 enzyme, which is mostly found in the brain, gradually tapered off over time. When these mice were 4 months old, the animals had lost about 80 percent of the enzyme.
Alzheimer’s mice with normal BACE1 levels experienced a steady increase in plaques, clearly seen in samples of their brains. In Alzheimer’s mice without BACE1, however, the clumps followed a different trajectory. The number of plaques initially grew, but by the time the mice were around 6 months old, those plaques had mostly disappeared. And by 10 months, “we hardly see any,” Yan says.

Cirrito was surprised that getting rid of BACE1 later in life didn’t just stop plaques from forming, but removed them, too. “It is possible that perhaps a therapeutic agent targeting BACE1 in humans might have a similar effect,” he says.

Drugs that target BACE1 are already in development. But the enzyme has other jobs in the brain, such as potentially affecting the ability of nerve cells to communicate properly. It may be necessary for a drug to inhibit some, but not all, of the enzyme, enough to prevent plaque formation but also preserve normal signaling between nerve cells, Yan says.

What a spectacular Easter basket tardigrade eggs would make — at least for those celebrating in miniature.

A new species of the pudgy, eight-legged, water creatures lays pale, spherical microscopic eggs studded with domes crowned in long, trailing streamers.

Eggs of many land-based tardigrades have bumps, spines, filaments and such, presumably to help attach to a surface, says species codiscoverer Kazuharu Arakawa. The combination of a relatively plain surface on the egg itself (no pores, for instance) plus a filament crown helps distinguish this water bear as a new species, now named Macrobiotus shonaicus, he and colleagues report February 28 in PLOS ONE.
With about 20 new species added each year to the existing 1,200 or so known worldwide, tardigrades have become tiny icons of extreme survival (SN Online: 7/14/17).

“I was actually not looking for a new species,” Arakawa says. He happened on it when searching through moss he plucked from the concrete parking lot at his apartment. He routinely samples such stray spots to search for tardigrades, one of his main interests as a genome biologist at Keio University’s Institute for Advanced Biosciences in Tsuruoka City, Japan.
These particular moss-loving creatures managed to grow and reproduce in the lab —“very rare for a tardigrade,” he says. He didn’t realize it was an unknown species until he started deciphering the DNA that makes up some of its genes. The sequences he found didn’t match any in a worldwide database.

His two coauthors, at Jagiellonian University in Krakow, Poland, worked out that he had found a new member of a storied cluster of relatives of the tardigrade M. hufelandi. That species, described in 1834, kept turning up across continents around the world — or so biologists thought for more than a century. Realization eventually dawned that the single species that could live in such varied places was actually a complex of close cousins.

And now M. shonaicus adds yet another cousin to a group of about 30. Who knows where the next one will turn up. “I think there are lots more to be identified,” Arakawa says.

Adult mice and other rodents sprout new nerve cells in memory-related parts of their brains. People, not so much. That’s the surprising conclusion of a series of experiments on human brains of various ages first described at a meeting in November (SN: 12/9/17, p. 10). A more complete description of the finding, published online March 7 in Nature, gives heft to the controversial result, as well as ammo to researchers looking for reasons to be skeptical of the findings.

In contrast to earlier prominent studies, Shawn Sorrells of the University of California, San Francisco and his colleagues failed to find newborn nerve cells in the memory-related hippocampi of adult brains. The team looked for these cells in nonliving brain samples in two ways: molecular markers that tag dividing cells and young nerve cells, and telltale shapes of newborn cells. Using these metrics, the researchers saw signs of newborn nerve cells in fetal brains and brains from the first year of life, but they became rarer in older children. And the brains of adults had none.

There is no surefire way to spot new nerve cells, particularly in live brains; each way comes with caveats. “These findings are certain to stir up controversy,” neuroscientist Jason Snyder of the University of British Columbia writes in an accompanying commentary in the same issue of Nature.

“The strangest place in the whole universe might just be right here.” So says actor Will Smith, narrating the opening moments of a new documentary series about the wonderful unlikeliness of our own planet, Earth.

One Strange Rock, premiering March 26 on the National Geographic Channel, is itself a peculiar and unlikely creation. Executive produced by Academy Award–nominated Darren Aronofsky and by Jane Root of the production company Nutopia and narrated by Smith, the sprawling, ambitious 10-episode series is chock-full of stunningly beautiful images and CGI visuals of our dynamic planet. Each episode is united by a theme relating to Earth’s history, such as the genesis of life, the magnetic and atmospheric shields that protect the planet from solar radiation and the ways in which Earth’s denizens have shaped its surface.
The first episode, “Gasp,” ponders Earth’s atmosphere and where its oxygen comes from. In one memorable sequence, the episode takes viewers on a whirlwind journey from Ethiopia’s dusty deserts to the Amazon rainforest to phytoplankton blooms in the ocean. Dust storms from Ethiopia, Smith tells us, fertilize the rainforest. And that rainforest, in turn, feeds phytoplankton. A mighty atmospheric river, fueled by water vapor from the Amazon and heat from the sun, flows across South America until it reaches the Andes and condenses into rain. That rain erodes rock and washes nutrients into the ocean, feeding blooms of phytoplankton called diatoms. One out of every two breaths that we take comes from the photosynthesis of those diatoms, Smith adds.
As always, Smith is an appealing everyman. But the true stars of the series may be the eight astronauts, including Chris Hadfield and Nicole Stott, who appear throughout the series. In stark contrast to the colorful images of the planet, the astronauts are filmed alone, their faces half in shadow against a black background as they tell stories that loosely connect to the themes. The visual contrast emphasizes the astronauts’ roles as outsiders who have a rare perspective on the blue marble.
“Having flown in space, I feel this connection to the planet,” Stott told Science News . “I was reintroduced to the planet.” Hadfield had a similar sentiment: “It’s just one tiny place, but it’s the tiny place that is ours,” he added.
Each astronaut anchors a different episode. In “Gasp,” Hadfield describes a frightening moment during a spacewalk outside the International Space Station when his eyes watered. Without gravity, the water couldn’t form into teardrops, so it effectively blinded him. To remove the water, he was forced to allow some precious air to escape his suit. It’s a tense moment that underscores the pricelessness of the thin blue line, visible from space, that marks Earth’s atmosphere. “It contains everything that’s important to us,” Hadfield says in the episode. “It contains life.”

Stott, meanwhile, figures prominently in an episode called “Storm.” Instead of a weather system, the title refers to the rain of space debris that Earth has endured throughout much of its history — including the powerful collision that formed the moon (SN: 4/15/17, p. 18). Stott describes her own sense of wonder as a child, watching astronauts land on our closest neighbor — and how the travels of those astronauts and the rocks they brought back revealed that Earth and the moon probably originated from the same place.

It’s glimpses like these into the astronauts’ lives and personalities — scenes of Hadfield strumming “Space Oddity” on a guitar, for example, or Stott chatting with her son in the family kitchen — that make the episodes more than a series of beautiful and educational IMAX films. Having been away from the planet for a short time, the astronauts see Earth as precious, and they convey their affection for it well. Stott said she hopes that this will be the ultimate takeaway for viewers, for whom the series may serve as a reintroduction to the planet they thought they knew so well. “I hope that people will … appreciate and acknowledge the significance of [this reintroduction],” she said, “that it will result in an awareness and obligation to take care of each other.”
Editor’s note: This story was updated on March 19, 2018, to add a mention of a second executive producer.