Why Insisting You’re Not Racist May Backfire? (Psychology)

When you insist you’re not racist, you may unwittingly be sending the opposite message.

That’s the conclusion of a new study by three Berkeley Haas researchers who conducted experiments with white participants claiming to hold egalitarian views. After asking them to write statements explaining why they weren’t prejudiced against Black people, they found that other white people could nevertheless gauge the writers’ underlying prejudice.

“Americans almost universally espouse egalitarianism and wish to see themselves as non-biased, yet racial prejudice persists,” says Berkeley Haas Asst. Prof. Drew Jacoby Senghor, one of the authors. “Our results suggest that the explicit goal of appearing egalitarian might blind people to the possibility that they could be communicating, and perpetuating, prejudicial attitudes.”

Co-authored by Derek Brown, PhD 24, and Michael Rosenblum, PhD 20—a post-doctoral scholar at NYU Stern School of Business—the study builds on past research finding people’s racial prejudice “leaks out” through nonverbal behavior, such as facial expressions or physical distance. In a series of experiments published in the Journal of Experimental Social Psychology, the researchers looked at perceptions based solely on written content.

They selected a group of white participants, screening out the small percentage who expressed overt prejudice, and scored subjects’ racial attitudes with two widely used assessments. The subjects were then asked: “Do you believe that all people are equal and should have equality of opportunity? Why or why not?,” and “Are you prejudiced toward Black people? Why or why not?” A second group of white participants, asked to read the written responses, accurately estimated how the writers had scored on the prejudice scale.

Linguistic cues

In a second experiment to parse out whether people were signaling racial attitudes intentionally or inadvertently, they asked one group to answer as honestly as possible and another group to answer “in the least prejudiced way possible.” There was no difference to the readers, who accurately scored both groups’ answers.

“That gave us some confidence that people are naturally trying to come across as egalitarian, but something about the language they choose is betraying them,” Rosenblum said.

What were those linguistic cues? The most powerful indicator, they found, was language that dehumanized or objectified African Americans—for example, “I have a great relationship with the Blacks.” Other characteristics such as defensiveness, references to personal responsibility, or a belief that equal opportunity exists were strongly associated with higher levels of prejudice, and cues such as focus on equity or an acknowledgement that inequality exists were associated with lower levels of prejudice. Interestingly, references to being colorblind or mentions of personal contact with Black people weren’t indicative of the white participants’ attitudes.

“This demonstrates that peoples’ use of the cues are meaningful not only for how prejudice is expressed, but also how egalitarianism is perceived,” said Brown.

Contagion effect

A third experiment had a sobering result. The researchers found that white participants reported greater prejudice towards Black people after reading statements from the self-avowed white egalitarians who scored high on underlying prejudice. In other words, the readers mirrored the attitudes of the writers, even when they identified themselves as ideologically dissimilar (conservative vs liberal).

“We don’t know reading other people’s views gave them permission to express more prejudice, or whether they thought that this is the norm and their actual prejudice level changed, but there seemed to be a contagion effect,” Rosenblum said. “One of the lessons here is that words carry weight. It does seem that this is one way that prejudice is unwittingly spread.”

Featured image credit: Yacobchuk for iStock/Getty Images


Reference: Drew S. Jacoby-Senghor, Michael Rosenblum, N. Derek Brown, Not all egalitarianism is created equal: Claims of nonprejudice inadvertently communicate prejudice between ingroup members, Journal of Experimental Social Psychology, Volume 94, 2021, 104104, ISSN 0022-1031, https://doi.org/10.1016/j.jesp.2021.104104. (https://www.sciencedirect.com/science/article/pii/S0022103121000044)


Provided by Berkeley Hass

Stanford Ecologists Develop A Theory About How Plants ‘Pay’ Their Microbes (Ecology)

Combining economics, psychology and studies of fertilizer application, researchers find that plants nearly follow an “equal pay for equal work” rule when giving resources to partner microbes – except when those microbes underperform.

“Equal pay for equal work,” a motto touted by many people, turns out to be relevant to the plant world as well. According to new research by Stanford University ecologists, plants allocate resources to their microbial partners in proportion to how much they benefit from that partnership.

“The vast majority of plants rely on microbes to provide them with the nutrients they need to grow and reproduce,” explained Brian Steidinger, a former postdoctoral researcher in the lab of Stanford ecologist, Kabir Peay. “The problem is that these microbes differ in how well they do the job. We wanted to see how the plants reward their microbial employees.”

In a new study, published July 6 in the journal American Naturalist, the researchers investigated this question by analyzing data from several studies that detail how different plants “pay” their symbionts with carbon relative to the “work” those symbionts perform for the plants – in the form of supplying nutrients, like phosphorus and nitrogen. What they found was that plants don’t quite achieve “equal pay” because they tend not to penalize low-performing microbes as much as would be expected in a truly equal system. The researchers were able to come up with a simple mathematical equation to represent most of the plant-microbe exchanges they observed.

“It’s a square root relationship,” said Peay, who is an associate professor of biology in the School of Humanities and Sciences. “Meaning, if microbe B does one-quarter as much work as microbe A, it still gets 50 percent as many resources – the square root of one-quarter.”

When the researchers tested their equation against 13 measurements of plant resource exchange with microbe partners, they were able to explain around 66 percent of the variability in the ratio of plant payments to two different microbes.

“The biggest surprise was the simplicity of the model,” said Steidinger. “You don’t get a lot of short equations in ecology. Or anywhere else.”

The fruit of frustration

When asked about the motivation for developing this equation, Steidinger summed it up with one word: frustration.

“There is a lot of really interesting literature in a field called ‘biological market theory’ that deals with how plants should preferentially allocate resources. But for the folks who actually run experiments, it is difficult to translate these models into clean predictions,” said Steidinger. “We wanted to make that clean prediction.”

An informal survey of the Peay lab members encouraged the researchers to start with the assumption of equal pay because most people agreed it was reasonable to guess that plants treat all microbes the same. To reach their final equation, Steidinger and Peay then factored in the diminishing returns seen in the fertilizer models and assessed them through the lens of biological market theory literature – which uses human markets as a mathematical analogy for exchanges of services in the natural world.

“It turns out if the plant is flush with resources – in this case, the sugars it feeds to its microbes – and if the nutrients are valuable enough, the plant pays its microbes according to a square-root law,” said Peay.

The square-root model is a strong start to addressing Steidinger’s original frustration but it is not quite at the level of realism he wants to eventually achieve.

“For instance, our model allows a useless microbe to be fired without the plant losing resources,” said Steidinger. “But, just as in the human world, it takes an investment to hire a microbe and that initial investment is a gamble that microbial layabouts can consume at their leisure.”

Weber’s Law

In an attempt to explain why plants follow the square-root model, the researchers turned to a law in psychology. Weber’s Law addresses how humans perceive differences in stimuli, such as noise, light or the size of different objects. It explains that, the stronger the stimuli, the worse we are at identifying when it changes. This law has been shown to hold for many non-human animals as well – describing, for example, how birds and bats forage for food and how fish school. Now the researchers suggest it’s a good analogy for their plant payment scheme too.

“Our model says that plant should go easy on low-performing microbes, seemingly overpaying the 25-percent-as-good microbe with 50 percent as much resources,” said Peay. “Well, it’s long been known that humans and non-human animals sense differences in quantity in a way that might bias them towards similar leniency.”

In other words, the researchers suggest that, like a human trying to detect the volumes of specific noises in a loud room, a plant making optimal payment decisions may be relatively insensitive to differences in the quality of its microbial employees. And the researchers argue that this insensitivity may be for the best, as it encourages plants to maintain a certain level of microbial diversity, which can help give the plant options for dealing with environmental changes it encounters throughout its lifetime.

“I think what we’re seeing is plants behave like animals not because they have the same perceptional limitations – and certainly not because they think like animals – but because we face similar challenges in making the best choices when there are diminishing returns on investment,” says Steidinger.

This research was funded by the U.S. Department of Energy Office of Science, Office of Biological & Environmental Research, Early Career Research Program; the National Science Foundation Division of Environmental Biology; and an Alexander von Humboldt Postdoctoral Research Fellowship.

Featured image: Plants and microbes exchange resources in symbiotic relationships – but Stanford ecologists suggest that plants don’t quite compensate all their microbes equally. (Image credit: Getty Images)


Provided by Stanford University

Discovery Shows How Tuning the Immune System May Enhance Vaccines And Ease Disease (Medicine)

A metabolic control pathway that regulates T follicular helper cells offers targets for drugs to stimulate the adaptive immune response.

Immunologists at St. Jude Children’s Research Hospital have identified a biological pathway that selectively controls how key immune cells, called T follicular helper cells, mature into functional components of the immune system.

The finding offers the promise of developing drugs to activate the metabolic pathway to enhance the effectiveness of vaccines, including those that protect against COVID-19. Such medications could stimulate the immune system to respond more vigorously following immunization to produce more antibodies against a virus or bacterium.

The work also lays the foundation for drugs that dial down the pathway to alleviate autoimmune diseases such as lupus. In such disorders, an overactive immune system produces antibodies that attack the body’s own tissues.

Led by Hongbo Chi, Ph.D. of the Department of Immunology, the researchers published their findings today in Nature.

Regulating the adaptive immune response

Chi and colleagues identified a metabolic control pathway that selectively regulates the development of specialized immune cells in the adaptive immune system. These cells are called T follicular helper cells.

The adaptive immune system is so named because when the body is infected by viruses or bacteria, it learns to target and attack them. T follicular helper cells activate the component of the adaptive immune system called humoral immunity. While humoral immunity attacks invaders circulating outside cells largely via the generation of antibodies, the other adaptive immune system component, cellular immunity, targets invaders inside infected cells.

In their experiments, the researchers sought to discover whether a metabolic control pathway existed that modified the T follicular helper cells to activate them. When such cells are activated, they help antibody-producing cells, called B cells, to mature and to generate infection-fighting antibodies.

Discovering a key pathway

To discover a possible control pathway, Chi and his colleagues used genetic techniques to delete in the T cells multiple enzymes known to be elements of such metabolic control pathways. Then, the scientists introduced the deletion-engineered T cells into mice followed by infection with a virus and tested whether the T cells lacking the enzyme were functional.

Their experiments revealed that one metabolic control pathway, called the CDP-ethanolamine pathway, selectively regulated the T follicular helper cells.

“This finding was a big surprise,” Chi said. “First of all, this pathway was considered to have a housekeeping function leading to the production of building blocks for the cell membrane. But we discovered that it has a major signaling function. And secondly, we were surprised that this pathway—and not other parallel pathways of this type—was the only one involved in regulating T follicular helper cells.”

As a complementary method to determine if the pathway selectively regulated the T follicular helper cells, the researchers deleted each of the key enzymes they identified in the CDP-ethanolamine pathway. They found that deletion of these enzymes, but not those of other parallel regulatory pathways, selectively impaired development of the T follicular helper cells, but not overall immune function.

Importantly, said Chi, those key enzymes could be targets for drugs that either enhance or inhibit the pathway, and thus the activity of the T cells.

“We are now exploring whether we can enhance the effectiveness of vaccines by using drugs that activate the pathway, to help these T cells mobilize the immune system to generate antibodies in response to a vaccine,” he said.

“On the other hand, to treat autoimmune disease, we’re interested in developing new ways to inhibit this pathway,” he said. “This approach is promising because we know that such activation or inhibition is highly selective for T follicular helper cells and would not affect other immune functions.”

The researchers are also delving into the structural mechanisms by which the enzymes work—insights that could offer such drug targets, Chi said.

Authors and funding

Guotong Fu, Ph.D., St. Jude Immunology, is the first author. The other St. Jude authors are Clifford Guy, Nicole Chapman, Gustavo Palacios, Jun Wei, Peipei Zhou, Lingyun Long, Yong-Dong Wang, Chenxi Qian, Yogesh Dhungana, Hongling Huang, Anil KC, Hao Shi, Sherri Rankin, Scott Brown, Amanda Johnson, Randall Wakefield, Camenzind Robinson, Jiyang Yu and Suzanne Jackowski. Additional authors are Xueyan Liu, University of New Orleans, and Anthony Sheyn, University of Tennessee Health Science Center.

The research was supported in part by the National Institutes of Health (AI105887, AI131703, AI140761, AI150241, AI150514, CA221290), Lupus Research Alliance and ALSAC, the fundraising and awareness organization of St. Jude.

Featured image: Hongbo Chi, Ph.D., of the St. Jude Department of Immunology, identified a biological pathway that selectively controls how key immune cells mature into functional components of the immune system. © St. Jude


Read the full text of the article:

Metabolic control of Tfh and humoral immunity by phosphatidylethanolamine.” Nature, Published July 7, 2021


Provided by St. Jude Children’s Research Hospital

The Evanescent Protoplanetary Disks Of Dolidze 25 (Planetary Science)

The dispersion times of protoplanetary disks, and in general the times available to form planets, are faster in low metallicity environments. This is what emerges from a study, led by Mario Guarcello of INAF of Palermo, conducted on archival data in optical and infrared bands and on X-ray observations obtained with NASA’s Chandra satellite.

The protoplanetary disks are hard structures from which planetary systems form, and featuring low-mass stars typically younger than 10 million years, these stars of pre-sequence . In recent years, the scientific community has paid great attention to the study of the evolution and dispersion of protoplanetary disks. This is thanks to instruments such as Alma which, thanks to an unprecedented angular resolution, have made it possible to observe many protoplanetary disks with great spatial detail, and also thanks to the evidence – obtained in recent years of research on exoplanets – that the presence of planets is a common feature among the stars in our galaxy.

In recent decades, several authors have estimated the number of stars with protoplanetary disks associated with star clusters with different ages. Thanks to these studies, we know that discs disperse rapidly: in star clusters of 5 million years the fraction of stars with discs is typically very low. This obviously places an important upper limit on the times a star can form a planetary system. In addition, some studies have also shown that in certain star formation environments, disks can disperse even more rapidly, so much so that planets cannot be formed. These are mainly environments characterized by intense local fields of ultraviolet radiation, emitted by rich populations of massive stars, or by high stellar densities.Ngc 6611 (the star cluster in the Eagle Nebula) and more populated OB associations , such as Cygnus OB2 .

Mario Giuseppe Guarcello, researcher at INAF in Palermo, first author of the study on the Dolidze 25 cluster published on A&A © INAF

The dispersion times of protoplanetary disks may also depend on the metallicity of the environment in which they were formed, that is, on the abundance of chemical elements heavier than hydrogen and helium. In fact, various properties of the discs depend on the abundance of heavy elements, such as the amount of dust present and the opacity of the material in the disc, i.e. the ability to absorb external radiation, properties that can be important in determining the dispersion times. discs. However, these environments are typically distant, and therefore difficult to study.

An exception to this rule is the young star cluster (about one million years) Dolidze 25 , at a distance of about 15 thousand light years from us, characterized by a low metallicity. By studying archival data in optical and infrared band and X-ray observations obtained with the NASA Chandra satellite, a team led by astrophysicist Mario Giuseppe GuarcelloINAF in Palermo has identified 1091 stars associated with the star cluster, determining their stellar parameters and calculating that about 34 percent of the stars of Dolidze 25 still have a protoplanetary disk. When compared with star clusters of the same age, this fraction is significantly low, and comparable to those star-forming regions where disks are dispersed more rapidly due to the properties of the surrounding environment.

“This result therefore indicates that the dispersion times of protoplanetary disks, and in general the times available to form planets, are faster in low metallic environments: an important result if we consider that the metallicity of the galaxy depends on both the distance from the center galactic that from the time considered ».

Featured image: Fraction of stars associated with 58 star clusters of various ages that still hosts a protoplanetary disk, depending on the age of the cluster. Clusters within 3,300 light years of the Sun are marked with black circles, clusters with a rich population of massive stars with red circles, low metallicity environments with green circles. The village of Dolidze 25 is marked with a star symbol. Credits: M. Guarcello et al., A&A, 2021


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Provided by INAF

The Jets Of Gamma-ray Bursts “Cool Down” Like This (Planetary Science)

Published on Nature Communications a study led by Samuele Ronchini, PhD student at Gssi and associate Infn, which sheds new light on the cooling processes in the jets of gamma-ray bursts, also suggesting that protons, and not electrons, emit radiation through synchrotron process

What are the processes that determine the cooling of relativistic particles in gamma-ray bursts, giving rise to the typical rapid decrease in flux that accompanies the initial explosion? To give a convincing answer to this question comes the work of a group of researchers from the Gran Sasso Science Institute (GSSI), in collaboration with colleagues from the National Institute of Astrophysics (Inaf) in which a report is presented that unites several gamma-ray bursts. (or Grb, Gamma-Ray Burst in English) during a transition phase of the phenomenon called “steep decay”. The uniqueness of this relationship led the group to go in search of a universal process that could give a correct interpretation. The studywas published today in the journal Nature Communications .

Gamma-ray bursts are considered to be among the most catastrophic and energetic events in the Universe as they can release in fractions of a second the entire energy emitted by a star such as the Sun throughout its life. The discovery of supernovae and gravitational waves associated with gamma bursts confirmed that some of these phenomena are the product of the collapse of a massive star, and others of the merger of two neutron stars. Known since the 1960s, their nature remained debated until the advent of the Neil Gehrels “Swift” Observatory, an observatory in orbit since 2004 dedicated to the detection, localization and characterization of Grb. After years of observing in different bands of the electromagnetic spectrum, from radio waves to gamma rays, we now know that Grbs are produced by jets of energy and matter launched from a black hole that expand at close to the speed of light. The particles carried by the jet are accelerated through shock waves or in magnetic reconnection regions, converting the kinetic (or magnetic) energy into electromagnetic radiation, which typically peaks in gamma rays. Subsequently the jet emits radiation at lower frequencies in the encounter and interaction with the interstellar medium, giving rise to the so-called afterglow phase, which can last from minutes, hours to months after the initial gamma-ray burst. The steep decay marks the boundary between the end of the initial impulsive phase, where most of the high-energy radiation is released, and the beginning of the afterglow . Its characteristic rapidity of decay in flow is generally associated with the curved geometry of the surface of the jet inside which the particles are accelerated and then dissipate their energy in the form of radiation.

However, this scenario, long accepted by the scientific community to interpret steep decay , fails to reproduce the spectral relationship found by the research team. The observational evidence therefore imposed a paradigm shift for the theoretical interpretation and the solution was found by assuming adiabatic cooling of the particles. By cooling we mean the process by which the particles lose their initial energy, while the term adiabatic refers to the expansion of the volume that contains the particles, which does not exchange heat with the external environment.

“I began to notice that we were observing something unique when I kept finding this strong spectral evolution in data analysis, independent of the characteristics of gamma-ray bursts. From there we began to understand the potential of the result ”, says Samuele Ronchini , a third-year doctoral student at GSSI. «It is certainly not easy to question well-established models in the scientific community and carrying out this work was a significant responsibility. However, the perseverance, competence and support of the entire research group allowed us to go all the way and obtain the desired results ». This result has a profound impact on the understanding of the emission and cooling processes of accelerated particles in Grb.

“The dominance of the adiabatic process indicates that the particles are unable to efficiently dissipate their energy, giving valuable information on the physical properties of the relativistic jet, such as the evolution of the magnetic field in the acceleration site, as well as on the nature of the particles themselves”, he explains. Gor Oganesyan , postdoc researcher at GSSI and second author of the article. “In particular, we understood that a mild decay of the magnetic field is required to reproduce the observed data, together with adiabatic cooling.”

Furthermore, the inefficient energy dissipation of the accelerated particles could suggest that it is protons, not electrons, that emit radiation via the synchrotron process. «Grb are particularly difficult to study», concludes Om Sharan Salafia of INAF in Milan, co-author of the study, «because, despite having some distinctive characteristics, they are extremely different from each other. Finding common and universal traits, as in this case, is the key to unifying them and understanding the physical processes that produce them ».

Future wide-field X-band observers able to monitor the entire evolution of the Grb from the very first moments after the explosion will be crucial to fully understand the result found by extending the work to a larger sample and in other bands of the spectrum. . “Understanding the mechanisms underlying these catastrophic events is of primary importance also in the context of multi-message astronomy”, underlines Marica Branchesi, full professor at GSSI and co-author of the work. “The combined study of gravitational waves and electromagnetic radiation associated with GRBs may in the future clarify many open questions related to the nature of the compact objects that generate them, their distribution on cosmological scales, as well as the physics of jets and the acceleration of particles at their indoor”.

Featured image: Artist’s impression of the cooling of gamma-ray bursts (Grb). Credits: Samuele Ronchini Gran Sasso Science Institute


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Provided by INAF

Metabolic Enzyme Promotes Neuroblastoma Aggressiveness (Medicine)

Potential treatment may prevent cancer cells from hijacking metabolic pathways

High-risk neuroblastoma is an aggressive childhood cancer with poor treatment outcomes. Despite intensive chemotherapy and radiotherapy, less than 50 percent of these children survive for five years. While the genetics of human neuroblastoma have been extensively studied, actionable therapeutics are limited.

Now researchers in the Feng lab at Boston University School of Medicine (BUSM), in collaboration with scientists in the Simon lab at the Perelman School of Medicine at the University of Pennsylvania (Penn), have not only discovered why this cancer is so aggressive but also reveal a promising therapeutic approach to treat these patients. These findings appear online in the journal Cancer Research, a journal of the American Association for Cancer Research.

“Our work pinpoints a targeted therapy for treating this group of at-risk patients, likely leading to improved survival,” said corresponding author Hui Feng, MD, PhD, associate professor of pharmacology and medicine at BUSM.

The research, led by Nicole M. Anderson, PhD, a former postdoc in the Feng lab and a current fellow in the Simon lab, combined patient sample analysis with genetic analysis of a zebrafish model of high-risk neuroblastoma and cell culture gene inactivation studies to understand the contribution of Dihydrolipoamide S-Succinyltransferase (DLST), a metabolic enzyme, and found that it promotes metastatic spread of this type of cancer.

“We show that elevated DLST expression not only predicts poor patient outcomes, but also disease aggression in human neuroblastoma. In the zebrafish model of neuroblastoma even a modest increase in DLST protein levels can accelerate neuroblastoma onset, increase tumor burden, and promote metastasis,” explains Celeste Simon, PhD, co-corresponding author and scientific director and investigator at Abramson Family Cancer Research Institute, UPenn at Penn. Conversely, they found a 50 percent reduction in DLST impairs neuroblastoma initiation and suppresses tumor aggression. DLST depletion in human neuroblastoma cells decreases cell growth and induces apoptosis (cell death).

The researchers utilized cell lines together with zebrafish and mouse neuroblastoma models to test the therapeutic efficacy of IACS-010759, a drug that is in clinical trials for treating other cancers. “Our studies revealed that human neuroblastoma cells are sensitive to IACS treatment, which slowed tumor cell growth in all models tested,” said Feng.

She hopes that this study will provide IACS-010759 as a targeted therapy for children with this aggressive disease.

Funding was provided by: N.M. Anderson: Alex’s Lemonade Stand Foundation, GR-000000165. J. Athoe and A. Lam: Boston University, Undergraduate Research Opportunity Award. J. Athoe and A. Kennedy: Alex’s Lemonade Stand Foundation, Pediatric Oncology Student Training Award. A.T. Look: NIH, R35CA210064. M.C. Simon: NIH, P01 CA104838 and R35 CA197602. H. Feng: NIH, CA134743 and CA215059; Boston University, 1UL1TR001430 and Ralph Edwards Career Development Professorship; Leukemia Research Foundation, Young Investigator Award; the American Cancer Society, RSG-17-204-01-TBG; and St. Baldrick Foundation, Career Development Scholar Award.


Reference: Nicole M. Anderson, Xiaodan Qin, Jennifer M. Finan, Andrew Lam, Jacob Athoe, Rindert Missiaen, Nicolas Skuli, Annie Kennedy, Amandeep S. Saini, Ting Tao, Shizhen Zhu, Itzhak Nissim, A. Thomas Look, Guoliang Qing, M. Celeste Simon and Hui Feng, “Metabolic Enzyme DLST Promotes Tumor Aggression and Reveals a Vulnerability to OXPHOS Inhibition in High-Risk Neuroblastoma”, Cancer Research, 2021. DOI: 10.1158/0008-5472.CAN-20-2153


Provided by BMC

New Type Of Massive Explosion Explains Mystery Star (Planetary Science)

‘Magneto-rotational hypernova’ soon after the Big Bang fuelled high levels of uranium, zinc in ancient stellar oddity

A massive explosion from a previously unknown source – 10 times more energetic than a supernova – could be the answer to a 13-billion-year-old Milky Way mystery.

Astronomers led by David Yong, Gary Da Costa and Chiaki Kobayashi from Australia’s ARC Centre of Excellence in All Sky Astrophysics in 3 Dimensions (ASTRO 3D) based at the Australian National University (ANU) have potentially discovered the first evidence of the destruction of a collapsed rapidly spinning star – a phenomenon they describe as a “magneto-rotational hypernova”.

The previously unknown type of cataclysm – which occurred barely a billion years after the Big Bang – is the most likely explanation for the presence of unusually high amounts of some elements detected in another extremely ancient and “primitive” Milky Way star.

That star, known as SMSS J200322.54-114203.3, contains larger amounts of metal elements, including zinc, uranium, europium and possibly gold, than others of the same age.

Neutron star mergers – the accepted sources of the material needed to forge them – are not enough to explain their presence.

The astronomers calculate that only the violent collapse of a very early star – amplified by rapid rotation and the presence of a strong magnetic field – can account for the additional neutrons required.

The research is published today in the journal Nature.

“The star we’re looking at has an iron-to-hydrogen ratio about 3000 times lower than the Sun – which means it is a very rare: what we call an extremely metal-poor star,” said Dr Yong, who is based at the ANU.

“However, the fact that it contains much larger than expected amounts of some heavier elements means that it is even rarer – a real needle in a haystack.”

The first stars in the universe were made almost entirely of hydrogen and helium. At length, they collapsed and exploded, turning into neutron stars or black holes, producing heavier elements which became incorporated in tiny amounts into the next generation of stars – the oldest still in existence.

Rates and energies of these star deaths have become well known in recent years, so the amount of heavy elements they produce is well calculated. And, for SMSS J200322.54-114203.3, the sums just don’t add up.

“The extra amounts of these elements had to come from somewhere,” said Associate Professor Chiaki Kobayashi from the University of Hertfordshire, UK.

“We now find the observational evidence for the first time directly indicating that there was a different kind of hypernova producing all stable elements in the periodic table at once — a core-collapse explosion of a fast-spinning strongly-magnetized massive star. It is the only thing that explains the results.”

Hypernovae have been known since the late 1990s. However, this is the first time one combining both rapid rotation and strong magnetism has been detected.

“It’s an explosive death for the star,” said Dr Yong. “We calculate that 13 billion-years ago J200322.54-114203.3 formed out of a chemical soup that contained the remains of this type of hypernova. No one’s ever found this phenomenon before.”

J200322.54-114203.3 lies 7500 light-years from the Sun, and orbits in the halo of the Milky Way.

Another co-author, Nobel Laureate and ANU Vice-Chancellor Professor Brian Schmidt, added, “The high zinc abundance is definite marker of a hypernova, a very energetic supernova.”

Head of the First Stars team in ASTRO 3D, Professor Gary Da Costa from ANU, explained that the star was first identified by a project called the SkyMapper survey of the southern sky.

“The star was first identified as extremely metal-poor using SkyMapper and the ANU 2.3m telescope at Siding Spring Observatory in western NSW,” he said. “Detailed observations were then obtained with the European Southern Observatory 8m Very Large Telescope in Chile.”

ASTRO 3D director, Professor Lisa Kewley, commented: “This is an extremely important discovery that reveals a new pathway for the formation of heavy elements in the infant universe.”

Other members of the research team are based at the Massachusetts Institute of Technology in the US, Stockholm University in Sweden, the Max Planck Institute for Astrophysics in Germany, Italy’s Istituto Nazionale di Astrofisica, and Australia’s University of New South Wales.

Featured image: The star SMSS J200322.54-114203.3. (centre, with crosshairs) in the south-eastern corner of the constellation Aquila (the Eagle) close to the border with Capricornus and Sagittarius. Credit: Da Costa/SkyMapper


Reference: Yong, D., Kobayashi, C., Da Costa, G.S. et al. r-Process elements from magnetorotational hypernovae. Nature 595, 223–226 (2021). https://doi.org/10.1038/s41586-021-03611-2


Provided by ASTRO3D

Molecular Imaging Improves Staging and Treatment of Pancreatic Ductal Adenocarcinomas (Medicine)

For patients with pancreatic ductal adenocarcinomas (PDAC), molecular imaging can improve staging and clinical management of the disease, according to research published in the June issue of The Journal of Nuclear Medicine. In a retrospective study of PDAC patients, the addition of PET/CT imaging with 68Ga-FAPI led to restaging of disease in more than half of the patients, most notably in those with local recurrence.

PDAC is a highly lethal cancer, with a five-year survival rate of less than 10 percent. Optimal imaging of PDAC is crucial for accurate initial TNM (tumor, node, metastases) staging and selection of the primary treatment. Follow-up imaging is also important to accurately detect local recurrence or metastatic spread as early and as completely as possible.

“Currently, contrast-enhanced CT is the gold standard when it comes to TNM staging, and PET imaging isn’t typically part of the clinical routine” stated Manuel Röhrich, MD, nuclear medicine physician at Heidelberg University Hospital in Heidelberg, Germany. “However, we know that PDAC is composed of certain fibroblasts that express fibroblast activation protein, which can be imaged with the novel PET radiotracer 68Ga-FAPI. Given this characteristic, we sought to explore the utility of 68Ga-FAPI PET/CT to image FDAC patients.”

The study included 19 FDAC patients who received contrast-enhanced CT imaging followed by 68Ga-FAPI PET/CT. Results from the 68Ga-FAPI PET/CT scans were then compared with TNM staging based on contrast-enhanced CT. Changes in oncological management were recorded.

68Ga-FAPI PET/CT-based TNM staging differed from contrast-enhanced CT imaging in 10 out of 19 patients, which resulted in changes in TNM staging. Of the 12 patients with recurrent disease, eight were upstaged, one was downstaged and three remained the same. In the seven patients newly diagnosed with PDAC, one was upstaged, while the staging remained the same for six of the patients.

“This analysis suggests that 68Ga-FAPI PET/CT is a promising new imaging modality in staging of PDAC that may help to detect new or clarify inconclusive results obtained by standard CT imaging,” said Röhrich. He added, “Improvement in survival can only be achieved by effective treatment approaches customized to the individual patient’s disease status. Thus, hybrid imaging using FAPI tracer may open up new applications in staging and restaging of PDAC.”

The authors of “Impact of 68Ga-FAPI-PET/CT imaging on the therapeutic management of primary and recurrent pancreatic ductal adenocarcinomas” include Manuel Röhrich, Fabian Staudinger, Dawn, P. Liew, Clemens Kratochwil and Hendrik Rathke, Department of Nuclear Medicine, Heidelberg University Hospital, Heidelberg, Germany; Patrick Naumann, Jakob Liermann,  Klaus Herfarth and Stefan A. Koerber, Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg, Germany, National Center for Tumor diseases (NCT), Heidelberg, Germany, and Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg, Germany; Frederik L. Giesel, Department of Nuclear Medicine, Heidelberg University Hospital, Heidelberg, Germany, and German Cancer Consortium (DKTK), partner site Heidelberg, Germany; Peter L. Choyke, Molecular Imaging Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland; Annika Wefers, Department of Neuropathology, Institute of Pathology, University Hospital Heidelberg, Heidelberg, Germany, and Clinical Cooperation Unit Neuropathology, German Consortium for Translational Cancer Research (DKTK), German Cancer Research Center (DKFZ), Heidelberg, Germany; Dirk Jäger, Department of Medical Oncology and Internal Medicine Virgin Islands, National Center for Tumor Diseases, University Hospital Heidelberg, Germany, and Clinical Cooperation Unit Applied Tumor Immunity, German Cancer Research Center (DKFZ), Heidelberg, Germany; Jürgen Debus, Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg, Germany, National Center for Tumor diseases (NCT), Heidelberg, Germany, and Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg, Germany, German Cancer Consortium (DKTK), Partner Site Heidelberg, Germany, Heidelberg Ion-Beam Therapy Center (HIT), Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg, Germany, and Clinical Cooperation Unit Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany; Uwe Haberkorn, Department of Nuclear Medicine, Heidelberg University Hospital, Heidelberg, Germany, and German Cancer Consortium (DKTK), Partner Site Heidelberg, Germany, Clinical Cooperation Unit, Department of Nuclear Medicine, German Cancer Research Center (DKFZ), Heidelberg, Germany, and Translational Lung Research Center Heidelberg, Member of the German Center for Lung Research DZL, Heidelberg, Germany; and Matthias Lang, Department of Neuropathology, Institute of Pathology, University Hospital Heidelberg, Heidelberg, Germany, and Department of Surgery, Heidelberg University Hospital, Heidelberg, Germany, Member of the German Center for Lung Research DZL, Heidelberg, Germany.

Featured image: Primary staging of a patient with PDAC. (A) Axial images of PDAC and liver in arterial (upper image) and venous (lower image) ceCT scan. (B) Mean intensity projection (MIP) images of 18F-FDG and FAPI PET/CT imaging. (C) Axial 18F-FDG and FAPI PET/CT images of same patient on level (blue line in A) of pancreatic tumor mass and another suspicious FAPI accumulation in projection on perihepatic lymph node. Metastatic situation, which had been revealed by FAPI PET/CT, was confirmed by biopsy of pulmonary lesion that was diagnosed as metastasis of known PDAC.


Provided by SNMMI

Researchers Detail the Most Ancient Bat Fossil Ever Discovered in Asia (Paleontology)

A new paper appearing in Biology Letters describes the oldest-known fragmentary bat fossils from Asia, pushing back the evolutionary record for bats on that continent to the dawn of the Eocene and boosting the possibility that the bat family’s “mysterious” origins someday might be traced to Asia.

A team based at the University of Kansas and China performed the fieldwork in the Junggar Basin — a very remote sedimentary basin in northwest China — to discover two fossil teeth belonging to two separate specimens of the bat, dubbed Altaynycteris aurora.

The new fossil specimens help scientists better understand bat evolution and geographic distribution and better grasp how mammals developed in general.

Upper molar of Altaynycteris aurora

“Bats show up in the fossil record out of the blue about 55-ish million years ago — and they’re already scattered on different parts of the globe,” said lead author Matthew Jones, a doctoral student at the KU Biodiversity Institute and Department of Ecology & Evolutionary Biology. “Before this, the earliest bats are known from a couple of places in Europe — Portugal and southern France — and Australia. So, when they show up early in the fossil record as these fragmentary fossils they’re already effectively worldwide. By the time we get their earliest known full skeletons, they look modern — they can fly, and most of them are able to echolocate. But we don’t really know anything about this transitional period from non-bats to bats. We don’t even really know what their closest living relatives are among mammals. It’s a really big evolutionary mystery where bats came from and how they evolved and became so specialized.”

Jones’ co-authors were K. Christopher Beard, senior curator at the KU Biodiversity Institute and Foundation Distinguished Professor of Ecology & Evolutionary Biology at KU; and Qiang Li and Xijun Ni of the Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology at the Chinese Academy of Sciences and the Center for Excellence in Life and Paleoenvironment at the Chinese Academy of Sciences.

Researchers bagging up sediment for screenwashing at the Junggar Basin field site.

The ancient bat teeth were discovered through painstaking fieldwork in the Junggar Basin, where the KU researchers worked at an isolated field site established by their Chinese colleagues, one of two sites in the region the team hope will continue yielding interesting fossils.

“This was concerted effort over a long period of time by our Chinese colleagues,” Jones said.

“They suspected that there were fossiliferous deposits from the Paleocene and Eocene, and they spent several years going out there, identifying where to find fossils. Chris was a part of several seasons of fieldwork there. I was a part of one season of fieldwork there. What we did was collect a bunch of sediment to screen wash, which is sort of like panning for gold. You pour a bunch of sediment into a sievelike apparatus and let all the dirt and everything fall out, and you’re only left with particles of a certain size, but also fossils.”

Beard said the fieldwork was an outgrowth of long-standing relationships between the KU team and its Chinese counterparts.

“We’ve been fortunate enough to be able to host our Chinese colleagues here in Lawrence for extended research visits, and they’ve more than reciprocated by hosting us for research and fieldwork in China. This work in the Junggar Basin is really trailblazing work because the fossil record in this part of China is only just barely beginning to emerge, and this area is very removed and isolated. It’s just a giant empty place. There are some camels, some snakes and lizards, but you don’t see many people there. That remoteness makes the logistics to do fieldwork there quite difficult and expensive because you’ve got to bring in all your food and water from far outside — all of that hindered research in this area previously.”

Following the challenging fieldwork, the residue left behind from the screen washing at the site was sorted at the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing. 

“In 2017, after we got back from the field, Xijun said. ‘Hey, one of the technicians picking through this sediment thinks they found a bat,’” Jones said. “Knowing I was interested in bats, they showed it to me. The next year, the other tooth was found — so there’s two teeth.”

Through meticulous morphological analysis of the teeth, along with biostratigraphy — or analyzing the position of layers of fossil remains in the deposits — the authors were able to date the specimens to the advent of the Eocene, the earliest period when bat fossils have been found anywhere on Earth. Indeed, the presence of these ancient bat fossils in Asia bolsters a theory that bats could have emerged from there in the first place, then distributed themselves worldwide when they later developed flight.

More fieldwork in the area is ongoing, and Jones and Beard said they were hopeful to find even older specimens, perhaps even dating to the Paleocene, the epoch before the Eocene, when researchers believe bats probably originated. Yet the particulars of Altaynycteris aurora remain hazy — for instance, it’s impossible to say from teeth fragments if the animal could fly or echolocate.

“These teeth look intermediate, in between what we would expect a bat ancestor to look like — and in fact, what a lot of early Cenozoic insectivorous mammals to do look like — and what true bat looks like,” Jones said. “So, they have some features that are characteristic of bats that we can point to and say, ‘These are bats.’ But then they have some features that we can call for simplicity’s sake ‘primitive.’”

The researchers said the new fossils help fill in a gap to understanding the evolution of bats, which remains a puzzle to experts — and could teach us more about mammals in general.

“I can think of two mammal groups that are alive today that are really weird,” Beard said. “One of them is bats, because they fly — and that’s just ridiculous. The other one is whales, because they’re completely adapted to life in the ocean, they can swim, obviously, and they do a little bit of sonar echolocation themselves. We know a lot about transitional fossils for whales. There are fossils from places like Pakistan that were quadrupedal mammals that looked vaguely doglike. We have a whole sequence of fossils linking these things that were clearly terrestrial animals walking around on land, through almost every kind of transitional phase you can imagine, to a modern whale. This isn’t true for bats. For bats, literally you’ve got a normal mammal and then you’ve got bats — and anytime you’ve got a fossil record that’s a giant vacuum, we need work that can fill partly that. This paper is at least a step along that path.”

Top photo: The ancient bat teeth were discovered through painstaking fieldwork in the Junggar Basin, where the KU researchers worked at an isolated field site established by their Chinese colleagues. Credit: Matthew Jones

Right photo: Upper molar of Altaynycteris aurora. Credit: Li Qiang

Bottom right photo: Researchers bagging up sediment for screenwashing at the Junggar Basin field site. Credit: Matthew Jones.


Provided by University of Kansas