Researchers Explore Origin Of Aluminum-26 (Particle Physics)

Scientists from the University of Surrey and the FRIB Laboratory at MSU teamed up to explore the origin of aluminum-26, a rare isotope that offers a window into dying stars. Their findings, “Exploiting Isospin Symmetry to Study the Role of Isomers in Stellar Environments,” were published in Physical Review Letters.

Aluminum-26 provides rare insight into processes in stars. It decays into magnesium-26, which emits a characteristic gamma ray observable with satellites. Magnesium-26 is detectable in presolar grains of material from stars that existed before the sun. The composition of these grains carries the fingerprints of their parent stars. The destruction rate of aluminum-26 by capturing a proton is critical for interpreting the amount of magnesium-26 observed in the universe. This research showed that the destruction of aluminum-26 by proton capture on the long-lived state is eight times less frequent than previously estimated.

Gavin Lotay, senior lecturer and director of learning and teaching at the University of Surrey, was the project’s spokesperson. Alexandra Gade, professor of physics at FRIB and in MSU’s Department of Physics and Astronomy and FRIB deputy scientific director, led part of the MSU collaboration.

Aluminum-26 has a long-lived quantum state that is difficult to study in a controlled way in the laboratory. The team used a transfer reaction that added a neutron to the radioactive isotope silicon-26 to study excited quantum states in silicon-27. These are the same states that are populated in the proton capture on the long-lived quantum state of aluminum-26. This was possible because protons and neutrons are subject to a symmetry that makes adding a proton to the long-lived state in aluminum-26 equivalent to adding a neutron to the ground state of silicon-26. The measurement used the Gamma-Ray Energy Tracking In-beam Nuclear Array (GRETINA), a national resource, and the laboratory’s S800 Spectrograph.

This research stems from a longstanding collaboration between the FRIB Laboratory and the University of Surrey, where direct nuclear reactions are used to populate quantum states whose exact energies and properties are of relevance to reactions that happen in stars. The staple of the collaboration has been the use of very sensitive gamma-ray spectroscopy to tag and characterize the excited quantum states of interest. Lotay eagerly anticipates the start of science at FRIB to further his research. He has submitted three proposals for beam time at FRIB that will be considered by the first FRIB Program Advisory Committee later this summer. 

“We have now reached a truly exciting time in science, where we are able to directly probe the processes that occur in exploding stars,” said Lotay. “These celestial objects are responsible for the rich variety of chemical elements we find all around us and, by coupling gamma-ray spectroscopy with direct reaction techniques, the collaboration has been successful in obtaining key information needed to understand their properties. The collaboration is now poised to significantly expand the scope of its nuclear astrophysics program and capitalize on the vast swathe of opportunities available at the soon-to-open FRIB facility.”

This research was funded by the U.S. Department of Energy (DOE) Office of Science Office of Nuclear Physics; the National Science Foundation; and the DOE National Nuclear Security Administration through the Nuclear Science and Security Consortium and the Science and Technologies Facilities Council of the United Kingdom.

The U.S. Department of Energy recently highlighted the research on its website.

Featured image: The illustration shows an aluminum-26 nucleus (green) escaping a supernova explosion. It will subsequently decay via gamma-ray emission that can be observed by satellites. Credit: Erin O’Donnell, FRIB


Provided by FRIB

Food Scientists Create National Atlas For Deadly Listeria (Biology)

Among the deadliest of foodborne pathogens, Listeria monocytogenessoon may become easier to track down in food recalls and other investigations, thanks to a new genomic and geological mapping tool created by Cornell food scientists.

The national atlas will tell scientists where listeria and other related species reside within the contiguous United States, which could help them trace and pinpoint sources of listeria found in ingredients, food processing facilities and finished products, according to research published July 15 in Nature Microbiology.

“As we’re trying to figure out the risk of getting listeria from soil and different locations, our group created a more systematic way of assessing how frequently different listeria are found in different locations,” said senior author Martin Wiedmann, Ph.D. ’97, the Gellert Family Professor in Food Safety and Food Science in the College of Agriculture and Life Sciences. “We’ve studied listeriain places as diverse as New York, Colorado and California, but before this atlas, [it] was difficult to make comparisons and assess listeria diversity in different locations.”

Listeria mononcytogenes in foods can make people extremely sick. The Centers for Disease Control and Prevention (CDC) estimate that each year 1,600 people in the U.S. get listeriosis; of those, about 260 die.

Knowing that listeria occurs naturally in soil, the Cornell group asked hundreds of other scientists across the country to scoop up soil samples from generally undisturbed places in the natural world, such as the off-trail areas of state and national parks.

From these samples, the group developed a nationwide atlas of 1,854 listeria isolates, representing 594 strains and 12 families of the bacteria called phylogroups.

Lead author Jingqiu Liao, Ph.D. ’20, who worked in Wiedmann’s laboratory as a graduate student, is now a post-doctoral researcher at Columbia University. She had supplemented the research by acquiring soil samples in her own travels and found listeriapresent across a wide range of environmental circumstances. This bacterium is controlled mainly by soil moisture, salinity concentrations and molybdenum – a trace mineral found in milk, cheese, grains, legumes, leafy vegetables and organ meats.

“The goal of this work was to systematically collect soil samples across the United States,” said Liao, “and to capture the true large-scale spatial distribution, genomic diversity and population structure of listeria species in the natural environment.

“With whole genome sequencing and comprehensive population genomics analyses,” Liao said, “we provided answers to the ecological and evolutionary drivers of bacterial genome flexibility – an important open question in the field of microbiology.”

Liao explained that this work can serve as a reference for future population genomics studies and will likely benefit the food industry by locating listeria contaminations that may have a natural origin.

If listeria is found in a processing facility in the western U.S., for example, and that facility had used ingredients from a distant state, Wiedmann said, “knowing the genomic information of listeriaisolates and their possible locations across the U.S., we can better narrow the origins to a specific region. You can use this information almost like a traceback. It’s not always proof, but it leads you to evidence.”

In addition to Wiedmann and Liao, the other authors on “Nationwide Genomic Atlas of Soil-Dwelling Listeria Reveals Effects of Selection and Population Ecology on Pangenome Evolution,” are Daniel Buckley, professor of microbial ecology in the School of Integrative Plant Science Soil and Crop Sciences Section; Otto Cordero, associate professor of civil and environmental engineering, Massachusetts Institute of Technology (MIT); Shaul Pollak, postdoctoral researcher, MIT; Daniel Weller, Ph.D. ’18, researcher, CDC; and Sean (Xiaodong) Guo, Cornell research technician.

The research was funded by the Center for Produce Safety in Woodland, California.

Featured image: Listeria, shown here in Martin Wiedmann’s laboratory, will be easier to trace in food recalls, thanks to a new genomic and geological mapping tool developed by a group led by Jingqiu Liao, Ph.D. ’20. © Provided


Provided by Cornell University

Breath Test To Determine Correct Treatment For Epilepsy (Medicine)

Breath instead of blood: researchers from the University of Basel have developed a new test method to measure treatment success in epilepsy patients. They hope that this will enable doctors to react more precisely when treating the disease.

Epilepsy affects some 50 million people worldwide and pharmaceutical treatment of the disease is a tightrope walk, as the dose must be tailored precisely to the individual patient: “Slightly too little and it isn’t effective. Slightly too much and it becomes toxic,” explains Professor Pablo Sinues.

Sinues is Botnar Research Professor of Pediatric Environmental Medicine at the University of Basel and University Children’s Hospital Basel (UKBB). He is also a member of the Department of Biomedical Engineering at the University of Basel. Together with colleagues from University Hospital Zurich (UHZ), he spent two and a half years looking for a way to tailor the dosage of drugs administered to epilepsy patients as precisely as possible. They ultimately achieved this goal with the help of a breath test. The advantage is that monitoring does not require a blood sample, which can always be a stress factor for children. And as the sample doesn’t need to be sent to the laboratory first, the results are available immediately.

Searching for the tiniest concentrations

“You can think of it as being like the alcohol test that police use when they stop drivers,” Sinues explains. The difference is that this breath measurement device is actually a big machine. “Because alcohol is present at high concentrations in breath, one only need a small device. But we’re searching for a droplet in 20 swimming pools,” he says. The researchers want to use the results to determine whether the active substances are present at the right concentrations in the body and whether they have the desired effect on the disease.

Their efforts have not been in vain: both among the young patients at UKBB and the adult reference group at the University Hospital Zurich, the breath tests produced the same results as conventional blood tests, as reported by the research group in their study published in Communications Medicine. This means that in addition to blood tests, there is a second way of monitoring epilepsy treatment – and the method also provides further information on the patient’s metabolism that doctors can use in the therapy.

Interdisciplinary collaboration is a recipe for success

The special thing about this research project is the unique dovetailing of science and medical practice at the University of Basel, says Sinues: “Thanks to this favorable initial situation, we are able to build machines that are precisely tailored to the needs of doctors.”

At UKBB, the rapid availability of test results is a particular advantage of the new method: young patients require constant adjustments of their medication because their metabolism changes as they grow. The new technology provides doctors with a non-invasive test that gives them immediate clues as to how well the course of therapy is going. This enables them to respond quickly if the dose has to be adjusted.

It took four years to reach this breakthrough and the technique is not yet suitable for widespread use – but that is the goal that Sinues has set himself. Indeed, the start-up “Deep Breath Intelligence” was founded specifically for that purpose and now aims to obtain a license for the measurement technique.

Featured image: Fast and accurate: The machine that Prof. Dr. Pablo Sinues and his team have developed aims to be able to react more precisely in the therapy of epilepsy (Image: UKBB).


Original article

Kapil Dev Singh et al. Personalised therapeutic management of epileptic patients guided by pathway-driven breath metabolomics. Communications Medicine (2021); doi: 10.1038/s43856-021-00021-3


Provided by University of Basel

Astronomers Discovered Massive Exoplanet Orbiting Its Host Star Once Every 1.1 Million Years (Planetary Science)

Astronomers with COol Companions ON Ultrawide orbiTS (COCONUTS) program, the COCONUTS-2 system, have identified a massive exoplanet, “COCONUTS-2b” in the COCONUTS-2A system, orbiting a low mass red dwarf star L 34-26. This planet has 6.3 times the mass of the Jupiter and orbits the parent star once every 1.1 million years at a distance of 6,471 AU (astronomical units). Their study recently appeared in Astrophysical Journal Letters.

L 34-26 also called COCONUTS-2A and TYC 9381-1809-1, is a M3-type dwarf star located 35 light-years away in the constellation of Chamaeleon. The star is about one-third the mass of the Sun and between 150 and 800 million years old.

Astronomers estimated that the planet has temperature of about 434 K. They also showed that, it is the nearest imaged exoplanet to Earth known to date.

In addition, astronomers suggested that, the skies of COCONUTS-2b would look dramatically different compared to the skies on the earth, due to its wide-separation orbit and cool host star.

While, the nighttime and daytime would look basically the same, with the host star appearing as a bright red star in the dark sky.

After TYC 9486-927-1b at a projected separation of 6,900 AU, this planet is the second widest and after WD 0806-661b with a temperature of 328 K this planet is the second coldest imaged exoplanet discovered so far.

COCONUTS-2b can be directly imaged thanks to emitted light produced by residual heat trapped since the planet’s formation. Still, the energy output of the planet is more than a million times weaker than the Sun’s, so the planet can only be detected using lower-energy infrared light.

The results were published in the Astrophysical Journal Letters.

Featured image: This image shows COCONUTS-2b (left) and its host star, COCONUTS-2A (right). Image credit: Zhang et al., doi: 10.3847/2041-8213/ac1123.


Reference: Zhoujian Zhang et al. 2021. The Second Discovery from the COCONUTS Program: A Cold Wide-orbit Exoplanet around a Young Field M Dwarf at 10.9 pc. ApJL 916, L11; doi: 10.3847/2041-8213/ac1123


Note for editors of other websites: To reuse this article fully or partially kindly give credit either to our author S. Aman or provide a link of our article

Modern Crocodile’s ‘Grandfather,’ 150 Million Years Old, Discovered in Chile Fossil (Paleontology)

Paleontologists have identified a new genus and species of small-sized mesoeucrocodylian from the fossilized remains found in the Patagonian mountains of southern Chile.

A 150-million-year-old fossilized skeleton discovered in the mountains of southern Chile was determined to be the ancestor of the modern crocodile, the Argentine Museum of Natural Sciences announced on Friday.

The species, named Burkesuchus mallingrandensis, was found in 2014 in an Andean fossil deposit near the Patagonian town of Mallin Grande by Argentine and Chilean researchers. Since then it has been analyzed at the Argentine Museum of Natural Sciences (MACN) in Buenos Aires.

The specimen is a “grandfather” of current crocodiles and should allow scientists to understand how they evolved, the museum said.

Fossilized bones of the Burkesuchus mallingrandensis, which could help to shed light on the origin of modern crocodiles, are pictured in Buenos Aires, Argentina April 24, 2020. Laboratorio de Anatomia Comparada – Museo de Ciencias Naturales “Bernardino Rivadavia”/Handout via REUTERS

Scientists believe the fossil will help them understand how these reptiles went from being terrestrial to aquatic. Along with other fossils, the discovery supports the idea that South America was the cradle of evolution for crocodiles.

About 200 million years ago “crocodiles were smaller, and did not live in water. Paleontologists always wanted to know what that transition was like,” Federico Agnolin, who found the specimen, told Reuters.

“What Burkesuchus shows is a series of unique traits, which no other crocodile has because they were the first that began to get into the water, into fresh water,” Agnolin said.

According to the MACN, crocodiles appeared at the beginning of the Jurassic period, around the time of the first dinosaurs. In a few million years they got into the water, thanks to the existence of warm and shallow seas. South America is known for its richness in marine crocodile fossils.

paper on the findings was published in the journal Scientific Reports.

Featured image: Paleontologist Fernando Novas holds the fossil skull of the Burkesuchus mallingrandensis, which could shed light on the origin of modern crocodiles, in Buenos Aires, Argentina March 9, 2021. Laboratorio de Anatomia Comparada – Museo de Ciencias Naturales “Bernardino Rivadavia”/Handout via REUTERS


Reference: F.E. Novas et al. 2021. New transitional fossil from late Jurassic of Chile sheds light on the origin of modern crocodiles. Sci Rep 11, 14960; doi: 10.1038/s41598-021-93994-z


Provided by REUTERS

Some Birds Pluck Hair Directly from Live Mammals (Biology)

Researchers from the University of Illinois at Urbana-Champaign and the Universidade Federal do Rio Grande do Sul have observed several bird species exhibiting a behavior that the authors are terming kleptotrichy (from Greek ‘klepto-’ — to steal + ‘trich-’ — hair).

Dozens of online videos document an unusual behavior among tufted titmice and their closest bird kin. A bird will land on an unsuspecting mammal and, cautiously and stealthily, pluck out some of its hair.

Henry Pollock photo.
Henry Pollock and his colleagues describe a surprising behavior among birds of the family Paridae. Photo courtesy Henry Pollock

A new paper in the journal Ecology documents this phenomenon, which the authors call “kleptotrichy,” from the Greek roots for “theft” and “hair.” The authors found only a few descriptions of the behavior in the scientific literature but came up with dozens more examples in online videos posted by birders and other bird enthusiasts. In almost all the videorecorded cases, the thief is a titmouse plucking hair from a cat, dog, human, raccoon or, in one case, porcupine.

Many species of titmice, chickadees and tits – all members of the family Paridae – are known to use hair or fur to line their nests, said Mark Hauber, a professor of evolution, ecology and behavior at the University of Illinois Urbana-Champaign who led the write-up with postdoctoral researcher Henry Pollock. The hair’s role in the nest is still debated, although it is more commonly used by birds nesting in temperate climates, so maintaining warmth in the nest is thought to be one advantage.

Photo of Jeffrey Brawn
U. of I. natural resources and environmental sciences professor Jeffrey Brawn first noticed a tufted timouse plucking hair from a sleeping raccoon. This prompted an exploration of the scientific literature and public documentation of the behavior. Photo by L. Brian Stauffer

The impetus for the study came from a chance sighting. Study co-author U. of I. natural resources and environmental sciences professor Jeffrey Brawn first observed the behavior with Pollock while on a spring bird count in central Illinois.

Scientists once assumed that birds with hair in their nests had collected it from the carcasses of dead mammals or found hair that had been shed into the environment, Brawn said.

“But the titmouse I saw was plucking hair from a live animal,” he said. “This was from a live raccoon with claws and teeth. And the raccoon didn’t seem to mind because it didn’t even wake up.”

A search of published research turned up just nine studies that documented 11 instances of the behavior, but a YouTube search yielded many more cases, Hauber said. Sometimes the target animals were sleeping, and sometimes they were awake.

Co-author Mark Hauber, a professor of evolution, ecology and behavior at the U. of I.
Co-author Mark Hauber, a professor of evolution, ecology and behavior at the U. of I. Photo by L. Brian Stauffer

“We know, of course, that birds use a variety of materials to line their nests,” Hauber said. “But why are these birds risking their lives to approach these mammals?”

The behavior suggests that the benefit of lining its nest with hair outweighs the danger to the bird, he said.

It may be that the birds simply need the hair to insulate their nests, but the presence of mammal hair – and the associated odor of the mammal – could also deter nest predators like snakes or other birds, the researchers said.

“There’s a local species called the great crested flycatcher, which, like the titmouse, is a cavity nester, that actually puts shed snakeskins into its nest, possibly to deter predators,” Brawn said.

“There are finches in Africa that put mammalian fecal material on top of their enclosed nests, presumably to confuse and thus keep predators away,” Hauber said. 

The hair also may repel nest and nestling parasites, which are a common threat to chick survival, especially in cavity nests like those of titmice, he said.

Regardless of the purpose of the behavior, the new paper is the first to document so many examples of hair-plucking by birds in a single report. In addition to citing nine papers about the phenomenon, it also links to dozens of online videos. Collectively, the videos show titmice – and in one case, a black-capped chickadee – plucking hair from 47 humans, 45 dogs, three cats, three raccoons and a porcupine.

“Unexpected interactions such as these remind us that animals exhibit all types of interesting and often overlooked behaviors and highlight the importance of careful natural history observations to shed light on the intricacies of ecological communities,” Pollock said.

Featured image: Screenshot from a video of a black-crested titmouse stealing fur from a sleeping fox, from the YouTube channel Texas Backyard Wildlife. Photo courtesy Texas Backyard Wildlife


Editor’s notes

The paper “What the pluck? Theft of mammal hair by birds is an overlooked but common behavior with fitness implications” is available online and from the U. of I. News Bureau. DOI: 10.1002/ecy.3501


Provided by University of Illinois

TESS Detects 158,505 Pulsating Red Giant Stars (Planetary Science)

Using observations from NASA’s Transiting Exoplanet Survey Satellite (TESS), astronomers have identified an unprecedented collection of pulsating red giant stars all across the sky. These stars, whose rhythms arise from internal sound waves, provide the opening chords of a symphonic exploration of our galactic neighborhood.

TESS primarily hunts for worlds beyond our solar system, also known as exoplanets. But its sensitive measurements of stellar brightness make TESS ideal for studying stellar oscillations, an area of research called asteroseismology.

“Our initial result, using stellar measurements across TESS’s first two years, shows that we can determine the masses and sizes of these oscillating giants with precision that will only improve as TESS goes on,” said Marc Hon, a NASA Hubble Fellow at the University of Hawaii in Honolulu. “What’s really unparalleled here is that TESS’s broad coverage allows us to make these measurements uniformly across almost the entire sky.”

Video: This visualization shows the new sample of oscillating red giant stars (colored dots) discovered by NASA’s Transiting Exoplanet Survey Satellite. The colors map to each 24-by-96-degree swath of the sky observed during the mission’s first two years. The view then changes to show the positions of these stars within our galaxy, based on distances determined by ESA’s (the European Space Agency’s) Gaia mission. The scale shows distances in kiloparsecs, each equal to 3,260 light-years, and extends nearly 20,000 light-years from the Sun.Credits: Credit: Kristin Riebe, Leibniz Institute for Astrophysics Potsdam

Hon presented the research during the second TESS Science Conference, an event supported by the Massachusetts Institute of Technology in Cambridge – held virtually from Aug. 2 to 6 – where scientists discuss all aspects of the mission. The Astrophysical Journal has accepted a paper describing the findings, led by Hon.

Sound waves traveling through any object – a guitar string, an organ pipe, or the interiors of Earth and the Sun – can reflect and interact, reinforcing some waves and canceling out others. This can result in orderly motion called standing waves, which create the tones in musical instruments.

Just below the surfaces of stars like the Sun, hot gas rises, cools, and then sinks, where it heats up again, much like a pan of boiling water on a hot stove. This motion produces waves of changing pressure – sound waves – that interact, ultimately driving stable oscillations with periods of a few minutes that produce subtle brightness changes. For the Sun, these variations amount to a few parts per million. Giant stars with masses similar to the Sun’s pulsate much more slowly, and the corresponding brightness changes can be hundreds of times greater. 

Oscillations in the Sun were first observed in the 1960s. Solar-like oscillations were detected in thousands of stars by the French-led Convection, Rotation and planetary Transits (CoRoT) space telescope, which operated from 2006 to 2013. NASA’s Kepler and K2 missions, which surveyed the sky from 2009 to 2018, found tens of thousands of oscillating giants. Now TESS extends this number by another 10 times.

“With a sample this large, giants that might occur only 1% of the time become pretty common,” said co-author Jamie Tayar, a Hubble Fellow at the University of Hawaii. “Now we can start thinking about finding even rarer examples.”

The physical differences between a cello and a violin produce their distinctive voices. Similarly, the stellar oscillations astronomers observe depend on each star’s interior structure, mass, and size. This means asteroseismology can help determine fundamental properties for large numbers of stars with accuracies not achievable in any other way.

Video: Listen to the rhythms of three red giants in the constellation Draco, as determined by brightness measurements from NASA’s Transiting Exoplanet Survey Satellite. To produce audible tones, astronomers multiplied the oscillation frequencies of the stars by 3 million times. It’s clear that larger stars produce longer, deeper pulsations than smaller ones.Credit: NASA/MIT/TESS and Ethan Kruse (USRA), M. Hon et al., 2021

When stars similar in mass to the Sun evolve into red giants, the penultimate phase of their stellar lives, their outer layers expand by 10 or more times. These vast gaseous envelopes pulsate with longer periods and larger amplitudes, which means their oscillations can be observed in fainter and more numerous stars.

TESS monitors large swaths of the sky for about a month at a time using its four cameras. During its two-year primary mission, TESS covered about 75% of the sky, each camera capturing a full image measuring 24-by-24 degrees every 30 minutes. In mid-2020, the cameras began collecting these images at an even faster pace, every 10 minutes.

This plot dissolves between an all-sky view of the sky from TESS and a color-coded map showing the masses of more than 150,000 red giant stars.
NASA’s Transiting Exoplanet Survey Satellite (TESS) imaged about 75% of the sky during its two-year-long primary mission. This plot dissolves between the TESS sky map and a “mass map” constructed by combining TESS measurements of 158,000 oscillating red giant stars with their distances, established by ESA’s (the European Space Agency’s) Gaia mission. The prominent band in both images is the Milky Way, which marks the central plane of our galaxy. In the mass map, green, yellow, orange, and red show where giant stars average more than 1.4 times the Sun’s mass. Such stars evolve faster than the Sun, becoming giants at younger ages. The close correspondence of higher-mass giants with the plane of the Milky Way, which contains our galaxy’s spiral arms, demonstrates that it contains many young stars.Credit: NASA/MIT/TESS and Ethan Kruse (USRA), M. Hon et al., 2021

The images were used to develop light curves – graphs of changing brightness – for nearly 24 million stars over 27 days, the length of time TESS stares at each swath of the sky. To sift through this immense accumulation of measurements, Hon and his colleagues taught a computer to recognize pulsating giants. The team used machine learning, a form of artificial intelligence that trains computers to make decisions based on general patterns without explicitly programming them.

To train the system, the team used Kepler light curves for more than 150,000 stars, of which some 20,000 were oscillating red giants. When the neural network finished processing all of the TESS data, it had identified a chorus of 158,505 pulsating giants.

Next, the team found distances for each giant using data from ESA’s (the European Space Agency’s) Gaia mission, and plotted the masses of these stars across the sky. Stars more massive than the Sun evolve faster, becoming giants at younger ages. A fundamental prediction in galactic astronomy is that younger, higher-mass stars should lie closer to the plane of the galaxy, which is marked by the high density of stars that create the glowing band of the Milky Way in the night sky.

“Our map demonstrates for the first time empirically that this is indeed the case across nearly the whole sky,” said co-author Daniel Huber, an assistant professor for astronomy at the University of Hawaii. “With the help of Gaia, TESS has now given us tickets to a red giant concert in the sky.”

TESS is a NASA Astrophysics Explorer mission led and operated by MIT in Cambridge, Massachusetts, and managed by NASA’s Goddard Space Flight Center. Additional partners include Northrop Grumman, based in Falls Church, Virginia; NASA’s Ames Research Center in California’s Silicon Valley; the Center for Astrophysics | Harvard & Smithsonian in Cambridge, Massachusetts; MIT’s Lincoln Laboratory; and the Space Telescope Science Institute in Baltimore. More than a dozen universities, research institutes, and observatories worldwide are participants in the mission.

Banner: Red giant stars near and far sweep across the sky in this illustration. Measurements from NASA’s Transiting Exoplanet Survey Satellite have identified more than 158,000 pulsating red giants across nearly the entire sky. Such discoveries hold great potential for exploring the detailed structure of our home galaxy. Credit: NASA’s Goddard Space Flight Center/Chris Smith (KBRwyle)


Reference: Marc Hon et al. 2021. A ‘Quick Look’ at All-Sky Galactic Archeology with TESS: 158,000 Oscillating Red Giants from the MIT Quick-Look Pipeline. ApJ, in press; arXiv: 2108.01241


Provided by NASA

World’s Earliest-Known Coin Mint and Spade Coin Discovered in China (Archeology)

Archaeologists have uncovered 2,640- to 2,550-year-old clay moulds for casting spade coins as well as fragments of finished spade coins at Guanzhuang in Xingyang, Henan province, China. The technical characteristics of the moulds demonstrate that the site — which was part of the Eastern Zhou period (770-220 BCE) bronze foundry — functioned as a mint for producing standardized coins.

“The origins of metal coinage and the monetization of ancient economies have long been a research focus in both archaeology and economic history,” said Dr. Hao Zhao from the School of History at Zhengzhou University and colleagues.

“The earliest coins are thought to have been minted in China, Lydia (in Western Asia Minor) and India.”

“Of these, the hollow-handle spade coin (kongshoubu) minted in China is a likely candidate for the first metal coinage.”

“The spade coin was an imitation of practical metal spades, but its thin blade and small size indicate that it had no utilitarian function.”

“The earlier spade coins had a fragile, hollow socket, reminiscent of a metal shovel. This socket was transformed into a thin, flat piece in later spade coins, and over time, characters were applied to the coins to mark their denominations.”

“Several versions of spade coins circulated across the Chinese Central Plains until their abolition by the First Emperor of Qin in 221 BCE.”

“Their origin and early history, and the social dynamics under which they were developed, however, remain controversial — a situation paralleled by the century-long debate over Lydian coins.”

Dr. Zhao and co-authors from Zhengzhou University and Peking University uncovered the ancient remains from different stages of the minting process at Guanzhuang in China’s Henan province.

The mint was part of a well-organized, integrated bronze foundry run under the auspices of the Zheng State.

“Guanzhuang is located in the Central Plains of China, some 12 km south of the Yellow River,” the archaeologists said.

“Continuous excavations since 2011 have revealed the general layout of a city, which consisted of two walled and moated enclosures.”

“The city was established in c. 800 BCE and abandoned after 450 BCE.”

“Excavations between 2015 and 2019 have revealed a large craft-production zone in the centre of the outer enclosure, immediately outside the southern gate of the inner city. This area included workshops involved in bronze, ceramic, jade and bone-artifact production.”

“The bronze foundry occupied the largest area. Its main features comprise more than 2,000 pits for dumping production waste, most between 1.5 and 3 m in diameter, with a depth of 1-2.5 m.”

“Alongside ceramic sherds, these pits contained abundant remains related to bronze-casting activities, including crucibles, ladles, bronze droplets, unfinished or broken bronze artifacts, clay moulds, charcoal, and furnace fragments.”

Spade coin SP-1 and its reconstruction; the outer mould (bottom left) is also used to reconstruct the spade coin. Image credit: H. Zhao.
Spade coin SP-1 and its reconstruction; the outer mould (bottom left) is also used to reconstruct the spade coin. Image credit: H. Zhao.

At the site, the researchers found two fragments of finished spade coins, dubbed SP-1 and SP-2.

“Coin SP-1 is so well preserved that its complete shape can be confidently reconstructed,” they said.

“This example is a typical pointed-shoulder spade coin, with a (restored) full length of 14.3 cm, a shoulder width of 6.35 cm and a maximum thickness of 0.9 mm. The weight of the extant coin is 27.1 g.”

“Reconstructing the volume of its missing feet at around 660 mm3 (4-5g), we estimate that the original weight of SP-1 was no less than 31 g, including the weight of the clay core inside the handle.”

As is typical of the earliest spade coins, there are no inscriptions indicating either the name of the locality where the coin was cast or its face value.

“Coin SP-2 was found in the context dated to the Eastern Han Dynasty (200 CE), and hence the coin must be considered a residual find, as spade coins had long been abolished by this time,” they said.

“Of this coin, only the handle and its clay core survive. They are of exactly the same shape and size as the corresponding portions of SP-1.”

The compositional analysis shows that the copper content of SP-1 and SP-2 is 62.5 and 76.46%, respectively.

“The existence of minting activity at Guanzhuang is further documented by numerous finds of clay cores and outer moulds for casting spade coins,” the scientists said.

“All the moulds are made of reddish fine silt, which was also the primary material for producing clay moulds to cast other types of bronze products at the Guanzhuang foundry.”

Combining the evidence from radiocarbon-dating, mould style and ceramic typology, they suggest that the Guanzhuang foundry was first established around 780 BCE.

During its initial phase of around 150 years, the foundry produced predominantly ritual vessels, weapons and chariot fittings — items used in ceremonies, warfare and other aspects of elite life.

Standardized minting started from the second phase of the Guanzhuang foundry, after c. 640 BCE and no later than 550 BCE, and it made use of the workshop’s existing bronze-production capacity.

“Currently, Guanzhuang is the earliest-known archaeological mint site dated by robust radiocarbon dates in the world, and coin SP-1 is the earliest spade coin — and, more generally, the earliest Chinese coin — recovered from a secure archaeological context,” the authors said.

“The minting techniques employed at Guanzhuang are characterized by batch production and a high degree of standardization and quality control, indicating that the production of spade coins was not a small-scale, sporadic experiment, but rather a well-planned and organised process in the heartland of the Central Plains of China.”

The team’s paper was published this week in the journal Antiquity.

Featured image: Spatial distribution of the minting remains in the Guanzhuang foundry’s excavation area: red dots: deposit with clay moulds; green dots: deposits with fragments of finished spade coins. Image credit: Z. Qu / H. Zhao.


Reference: Hao Zhao et al. Radiocarbon-dating an early minting site: the emergence of standardised coinage in China. Antiquity, published online August 6, 2021; doi: 10.15184/aqy.2021.94


Provided by Sci-news

How Authoritarian Leaders Maintain Support? (Psychology)

Study finds public anticorruption campaigns bolster leaders, even when such measures lack tangible results.

How do authoritarian regimes sustain their popularity? A novel study in China led by MIT scholars shows that anticorruption punishments meted out by government authorities receive significant support among citizens — who believe such actions demonstrate both competence and morally righteous leadership.

The findings help explain how authoritarian governments endure, not merely based on domination and fear, but as regimes generating positive public support over time.

“What we find is that not only does the punishment of corrupt officials increase the perception among citizens that there is a capable and competent government, but it also increases the belief that government authorities have moral commitments citizens care about,” says Lily Tsai, an MIT political scientist and co-author of a newly published paper detailing the study’s findings.

In the case of China, these anticorruption actions tend to consist of public punishments of lower-level local officials who have violated the law. It is not clear that such measures actually reduce corruption overall, but people are still influenced by public gestures involving crackdowns on malfeasance.

“It signals that there is someone in authority who is willing to create order and stability for the public,” Tsai notes.

The paper, “What makes anticorruption popular? Individual-level evidence from China,” has been published in advance online form in the Journal of Politics. The authors are Tsai, who is the Ford Professor of Political Science and MIT’s chair of the faculty; and Minh D. Trinh and Shiyao Liu, who are PhD candidates in political science at MIT.

Recession-proof support?

The study consists of a sophisticated public-opinion experiment conducted in China using “conjoint analysis,” a method that identifies how much relative influence different factors have on people’s views.

The researchers essentially conducted three iterations of a detailed public-opinion survey. Nearly 2,400 total participants, in both rural and urban settings, were presented with hypothetical profiles of pairs of government leaders and asked to evaluate their performances based on a range of supposed attributes and achievements — including their anticorruption activities. In these scenarios, the exact attributes and activities of the hypothetical leaders varied randomly, allowing the researchers to separate out the importance of anticorruption measures in the minds of citizens.

Other things being equal, in these hypothetical scenarios, survey participants preferred officials making higher-profile anticorruption efforts, up to 25 percent more often than other officials. The survey’s respondents placed more weight on the economic stewardship provided by government officials, but rated anticorruption activities as being about equal in importance to welfare provision and administering elections fairly.

More significantly, Tsai says, the experiment finds that public interest in anticorruption gestures exists independently of anything else in a government official’s resume.

“Independent of how well officials do at economic development, or providing social welfare, or implementing elections, anticorruption punishment can still be a very useful tactic for authorities who are seeking to bolster their public support,” Tsai observes.

Indeed, Tsai adds, the results have a somewhat ominous implication along those lines: “These findings could indicate anticorruption punishment is a useful way of recession-proofing public support.”

Making punishment visible

The authors also introduced several modifications to the structure of the conjoint analysis to learn why people support visible anticorruption measures. Their study finds two distinct reasons behind this support. First, those measures signal that the officials taking action have the capacity to take decisive actions. Second, anticorruption actions also signal that the values of officials are aligned with ordinary citizens — even when the same officials do not, say, administer local elections well enough to give voters a strong voice in selecting leaders.

“At least in the Chinese context, in both urban populations and rural populations in China, citizens see officials who punish other, lower-level officials for corruption as being more moral,” Tsai says. “They [think anticorruption officials] have the “’right intentions.’”

Moreover, Tsai adds, anticorruption gestures seem effective even in lieu of evidence that corruption might be consequently reduced. At least in political terms, staging a high-profile anticorruption campaign is what matters, more than quelling corruption.

“It’s in the interest of rulers to invest in anticorruption punishments even if that punishment does not decrease corruption,” Tsai says. “People have no data about how much corruption there is in government. What they can see more clearly are the incidents of punishment of corruption.”

In historical terms, Tsai adds, the results fit “a longstanding tradition in China where the rulers position themselves as the allies of ordinary people,” despite restricting individual liberties in many ways. That said, Tsai thinks the results describe a political dynamic that could be found in many nation-states, in many varieties: People will back leaders who support symbolic public punishments, conveying a message that the traditional social order will remain intact.

“People are often willing to sacrifice a lot for a sense of certainty,” Tsai says.

Featured image: Public anti-corruption gestures are an effective way for authoritarian governments to maintain public support, according to a study co-authored by MIT political scientist Lily Tsai.Credits:Image: Christine Daniloff, MIT, stock images


Reference: Lily L. Tsai, Minh D Trinh, and Shiyao Liu, “What Makes Anticorruption Punishment Popular? Individual-level Evidence from China”, The Journal of Politics, 2021. https://www.journals.uchicago.edu/doi/10.1086/715252


Provided by Massachusetts Institute of Technology