Mark D. Goodsell and Rhea Moutafis in their recently published paper calculated the mass of dark matter (DM). They found mass much below the Griest-Kamionkowski limit.
In 1990, Kim Griest and Marc Kamionkowski, using partial-wave unitarity and the observed density of the Universe, showed that a stable elementary particle which was once in thermal equilibrium cannot have a mass greater than 340 TeV.
Now, Mark and Rhea showed their results in agreement with Griest-Kamionkowski. They found highest singlet mass of 47.354 TeV (Tevatron) (with DM relic density of Ωh² = 0.122), which is much below Griest-Kamionkowski limit. But, what allowed them to calculate dark matter mass much below the Griest-Kamionkowski Limit?
Well, their detailed investigation on the (genuine) complementarity of the requirements of (full) unitarity including finite momentum scattering, vacuum stability and relic density to place an upper bound on a scalar dark matter model with colourful mediators for the first time, alongwith, automatisation of the group theory calculations implemented in SARAH v4.14.4, allowed them to put an upper bound on the dark matter mass well below the Griest-Kamionkowski limit.
Their study published in ArXiv on 16 Dec, 2020.
References: Mark D. Goodsell and Rhea Moutafis, “How heavy can dark matter be? Constraining colourful unitarity with SARAH”, ArXiv, pp. 1-23, 2020. https://arxiv.org/abs/2012.09022v1
Copyright of this article totally belongs to our author S. Aman. One is allowed to reuse it only by giving proper credit either to him or to us.
We don’t know why the universe appears to be expanding faster than it should. New ultra-precise distance measurements have only intensified the problem.
On December 3, humanity suddenly had information at its fingertips that people have wanted for, well, forever: the precise distances to the stars.
“You type in the name of a star or its position, and in less than a second you will have the answer,” Barry Madore, a cosmologist at the University of Chicago and Carnegie Observatories, said on a Zoom call last week. “I mean …” He trailed off.
“We’re drinking from a firehose right now,” said Wendy Freedman, also a cosmologist at Chicago and Carnegie and Madore’s wife and collaborator.
“I can’t overstate how excited I am,” Adam Riess of Johns Hopkins University, who won the 2011 Nobel Prize in Physics for co-discovering dark energy, said in a phone call. “Can I show you visually what I’m so excited about?” We switched to Zoom so he could screen-share pretty plots of the new star data.
The data comes from the European Space Agency’s Gaia spacecraft, which has spent the past six years stargazing from a perch 1 million miles high. The telescope has measured the “parallaxes” of 1.3 billion stars — tiny shifts in the stars’ apparent positions in the sky that reveal their distances. “The Gaia parallaxes are by far the most accurate and precise distance determinations ever,” said Jo Bovy, an astrophysicist at the University of Toronto.
Best of all for cosmologists, Gaia’s new catalogue includes the special stars whose distances serve as yardsticks for measuring all farther cosmological distances. Because of this, the new data has swiftly sharpened the biggest conundrum in modern cosmology: the unexpectedly fast expansion of the universe, known as the Hubble tension.
The tension is this: The cosmos’s known ingredients and governing equations predict that it should currently be expanding at a rate of 67 kilometers per second per megaparsec — meaning we should see galaxies flying away from us 67 kilometers per second faster for each additional megaparsec of distance. Yet actual measurements consistently overshoot the mark. Galaxies are receding too quickly. The discrepancy thrillingly suggests that some unknown quickening agent may be afoot in the cosmos.
“It would be incredibly exciting if there was new physics,” Freedman said. “I have a secret in my heart that I hope there is, that there’s a discovery to be made there. But we want to make sure we’re right. There’s work to do before we can say so unequivocally.”
That work involves reducing possible sources of error in measurements of the cosmic expansion rate. One of the biggest sources of that uncertainty has been the distances to nearby stars — distances that the new parallax data appears to all but nail down.
In a paper posted online last night and submitted to TheAstrophysical Journal, Riess’s team has used the new data to peg the expansion rate at 73.2 kilometers per second per megaparsec, in line with their previous value, but now with a margin of error of just 1.8%. That seemingly cements the discrepancy with the far lower predicted rate of 67.
Freedman and Madore expect to publish their group’s new and improved measurement of the cosmic expansion rate in January. They too expect the new data to firm up, rather than shift, their measurement, which has tended to land lower than Riess’s and those of other groups but still higher than the prediction.
Since Gaia launched in December 2013, it has released two other massive data sets that have revolutionized our understanding of our cosmic neighborhood. Yet Gaia’s earlier parallax measurements were a disappointment. “When we looked at the first data release” in 2016, Freedman said, “we wanted to cry.”
An Unforeseen Problem
If parallaxes were easier to measure, the Copernican revolution might have happened sooner.
Copernicus proposed in the 16th century that the Earth revolves around the sun. But even at the time, astronomers knew about parallax. If Earth moved, as Copernicus held, then they expected to see nearby stars shifting in the sky as it did so, just as a lamppost appears to shift relative to the background hills as you cross the street. The astronomer Tycho Brahe didn’t detect any such stellar parallax and thereby concluded that Earth does not move.
And yet it does, and the stars do shift — albeit barely, because they’re so far away.
It took until 1838 for a German astronomer named Friedrich Bessel to detect stellar parallax. By measuring the angular shift of the star system 61 Cygni relative to the surrounding stars, Bessel concluded that it was 10.3 light-years away. His measurement differed from the true value by only 10% — Gaia’s new measurements place the two stars in the system at 11.4030 and 11.4026 light-years away, give or take one or two thousandths of a light-year.
The 61 Cygni system is exceptionally close. More typical Milky Way stars shift by mere ten-thousandths of an arcsecond — just hundredths of a pixel in a modern telescope camera. Detecting the motion requires specialized, ultra-stable instruments. Gaia was designed for the purpose, but when it switched on, the telescope had an unforeseen problem.
The telescope works by looking in two directions at once and tracking the angular differences between stars in its two fields of view, explained Lennart Lindegren, who co-proposed the Gaia mission in 1993 and led the analysis of its new parallax data. Accurate parallax estimates require the angle between the two fields of view to stay fixed. But early in the Gaia mission, scientists discovered that it does not. The telescope flexes slightly as it rotates with respect to the sun, introducing a wobble into its measurements that mimics parallax. Worse, this parallax “offset” depends in complicated ways on objects’ positions, colors and brightness.
However, as data has accrued, the Gaia scientists have found it easier to separate the fake parallax from the real. Lindegren and colleagues managed to remove much of the telescope’s wobble from the newly released parallax data, while also devising a formula that researchers can use to correct the final parallax measurements depending on a star’s position, color and brightness.
Climbing the Ladder
With the new data in hand, Riess, Freedman and Madore and their teams have been able to recalculate the universe’s expansion rate. In broad strokes, the way to gauge cosmic expansion is to figure out how far away distant galaxies are and how fast they’re receding from us. The speed measurements are straightforward; distances are hard.
The most precise measurements rely on intricate “cosmic distance ladders.” The first rung consists of “standard candle” stars in and around our own galaxy that have well-defined luminosities, and which are close enough to exhibit parallax — the only sure way to tell how far away things are without traveling there. Astronomers then compare the brightness of these standard candles with that of fainter ones in nearby galaxies to deduce their distances. That’s the second rung of the ladder. Knowing the distances of these galaxies, which are chosen because they contain rare, bright stellar explosions called Type 1a supernovas, allows cosmologists to gauge the relative distances of farther-away galaxies that contain fainter Type 1a supernovas. The ratio of these faraway galaxies’ speeds to their distances gives the cosmic expansion rate.
Parallaxes are thus crucial to the whole construction. “You change the first step — the parallaxes — then everything that follows changes as well,” said Riess, who is one of the leaders of the distance ladder approach. “If you change the precision of the first step, then the precision of everything else changes.”
Riess’s team has used Gaia’s new parallaxes of 75 Cepheids — pulsating stars that are their preferred standard candles — to recalibrate their measurement of the cosmic expansion rate.
Freedman and Madore, Riess’s chief rivals at the top of the distance ladder game, have argued in recent years that Cepheids foster possible missteps on higher rungs of the ladder. So rather than lean too heavily on them, their team is combining measurements based on multiple kinds of standard-candle stars from the Gaia data set, including Cepheids, RR Lyrae stars, tip-of-the-red-giant-branch stars and so-called carbon stars.
“Gaia’s [new data release] is providing us with a secure foundation,” said Madore. Although a series of papers by Madore and Freedman’s team aren’t expected for a few weeks, they noted that the new parallax data and correction formula appear to work well. When used with various methods of plotting and dissecting the measurements, data points representing Cepheids and other special stars fall neatly along straight lines, with very little of the “scatter” that would indicate random error.
“It’s telling us we’re really looking at the real stuff,” Madore said.
This article is originally written by Natalie Wolchover and is republished here from quanta magazine under common creative licenses.
Researchers at the Niels Bohr Institute and the Department of Chemistry at University of Copenhagen, have recently designed a porous polymer aiming for the capture of small molecules. Ammonia is a toxic gas widely used as a reagent in industrial processes or resulting from agricultural activities, causing irritation in the throat, eye damage and even death to humans. Being able to capture it with this new method could have huge health benefits. The result is now published in ACS Applied Materials & Interfaces.
Associate professor at the Niels Bohr Institute, Heloisa Bordallo, explains: “If we want to use this material in a real application to solve an important societal problem like ammonia pollution, it is important to explain how ammonia is captured by the porous network in the polymer. This implies that we needed to come up with a technique that allows us to find out exactly how the interaction between the polymer and ammonia takes place. Being successful in answering this question, will make us able to understand better how this or other polymers can be efficient in multidisciplinary domains, including nanomedicine and protective coatings. If scaled up – which is not a simple process – this could have a significant positive impact on the working environment of many people all over the globe”.
The polymer showed surprisingly good characteristics already at the outset
Assistant professor Jiwoong Lee at the Chemistry Department and Rodrigo Lima, a former postdoc at the Niels Bohr Institute, synthesized 2 grams of the polymer, which doesn’t sound like a lot, but it is actually substantial, considering the amounts chemists normally work with is only a few milligrams. After this first step, the team used a lot of different techniques to characterize the material. Assistant professor Jiwoong Lee explains: “The synthesis process often involves washing the material with solvents and it was a nice surprise to realize that the porous polymer actually kept a portion of these solvents inside. This was indicative of the material’s ability to perhaps capture other pollutants, such as ammonia.”
The researchers performed experiments at the ISIS Neutron and Muon Source part of the STFC Rutherford Appleton Laboratory in the UK, where the dynamics of the hydrogen bonds was investigated by collecting neutron scattering data at low pressure to get ammonia into the polymer. Neutron scattering is a technique able to describe where the atoms are located and at the same describe how the atoms are moving inside a material. Afterwards, Rodrigo Lima, former postdoc at the Niels Bohr Institute, set up an experiment at the thermal analysis laboratory at the Niels Bohr Institute and demonstrated that ammonia was not only captured, but attached to the porous materials. “This was a real surprise! The polymer binds ammonia very strongly”, he says.
Characterizing the amorphous polymer turned out to be a challenge in itself
“In order to be able to explain this seemingly strong connection between the polymer and the ammonia, we needed to know the structure of the polymer. But since this particular polymer is amorphous, it is difficult to fully characterize its structure. In a way you could say that we had ticked the box of capturing the ammonia, but we still needed to explain how this happens – and for that we needed a better view of the structure, which was unattainable. Quite a dilemma to have full success in one part of the project, and not be able to explain exactly why”. Heloisa Bordallo explains.
The researchers made different combinations of the polymer building blocks and were able to calculate a spectra, using a computational modelling method called DFT, from a combination that came closest to being similar to the measurements in the real sample. This, finally, made them able to “tick the box” of interpreting how the polymer binds.
“There are numerous applications for a polymer that captures ammonia”, Jiwoong Lee explains. “It would be useful in labs, as coating for masks to wear for personal safety, as ammonia is toxic and also very corrosive. It could be used as filters, reducing the spread of ammonia released through the exhausts from many types of industry. Thinking ahead, it is possible that the polymer technique could be applied to other types of polluents as well.”
Machine learning and artificial intelligence
Heloisa Bordallo wishes to apply machine learning to amorphous systems. For this experiment, she and her colleagues made the experiment “by hand”, so to speak, but it is perhaps a more viable way to go about this process to use machine learning and artificial intelligence. Applying deep learning algorithms can help in accurately classifying amorphous materials and in characterizing their structural features. “Then by combining Machine Learning with theoretical calculations we will be able to analyze the neutron scattering data in a much more elegant way”, she says.
Over the past two years, astronomers have rewritten the story of our galaxy.
When the Khoisan hunter-gatherers of sub-Saharan Africa gazed upon the meandering trail of stars and dust that split the night sky, they saw the embers of a campfire. Polynesian sailors perceived a cloud-eating shark. The ancient Greeks saw a stream of milk, gala, which would eventually give rise to the modern term “galaxy.”
In the 20th century, astronomers discovered that our silver river is just one piece of a vast island of stars, and they penned their own galactic origin story. In the simplest telling, it held that our Milky Way galaxy came together nearly 14 billion years ago when enormous clouds of gas and dust coalesced under the force of gravity. Over time, two structures emerged: first, a vast spherical “halo,” and later, a dense, bright disk. Billions of years after that, our own solar system spun into being inside this disk, so that when we look out at night, we see spilt milk — an edge-on view of the disk splashed across the sky.
Yet over the past two years, researchers have rewritten nearly every major chapter of the galaxy’s history. What happened? They got better data.
On April 25, 2018, a European spacecraft by the name of Gaia released a staggering quantity of information about the sky. Critically, Gaia’s years-long data set described the detailed motions of roughly 1 billion stars. Previous surveys had mapped the movement of just thousands. The data brought a previously static swath of the galaxy to life. “Gaia started a new revolution,” said Federico Sestito, an astronomer at the Strasbourg Astronomical Observatory in France.
Astronomers raced to download the dynamic star map, and a flurry of discoveries followed. They found that parts of the disk, for example, appeared impossibly ancient. They also found evidence of epic collisions that shaped the Milky Way’s violent youth, as well as new signs that the galaxy continues to churn in an unexpected way.
Taken together, these results have spun a new story about our galaxy’s turbulent past and its ever-evolving future. “Our picture of the Milky Way has changed so quickly,” said Michael Petersen, an astronomer at the University of Edinburgh. “The theme is that the Milky Way is not a static object. Things are changing rapidly everywhere.”
The Earliest Stars
To peer back to the galaxy’s earliest days, astronomers seek stars that were around back then. These stars were fashioned only from hydrogen and helium, the cosmos’s rawest materials. Fortunately, the smaller stars from this early stock are also slow to burn, so many are still shining.
After decades of surveys, researchers had assembled a catalog of 42 such ancients, known as ultra metal-poor stars (to astronomers, any atom bulkier than helium qualifies as metallic). According to the standard story of the Milky Way, these stars should be swarming throughout the halo, the first part of the galaxy to form. By contrast, stars in the disk — which was thought to have taken perhaps an additional billion years to spin itself flat — should be contaminated with heaver elements such as carbon and oxygen.
In late 2017, Sestito set out to study how this metal-poor swarm moves by writing code to analyze the upcoming Gaia results. Perhaps their spherical paths could offer some clues as to how the halo came to be, he thought.
In the days following Gaia’s data release, he extracted the 42 ancient stars from the full data set, then tracked their motions. He found that most were streaming through the halo, as predicted. But some — roughly 1 in 4 — weren’t. Rather, they appeared stuck in the disk, the Milky Way’s youngest region. “What the hell,” Sestito wondered, though he used a different four-letter term. “What’s going on?”
Follow-up research confirmed that the stars really are long-term residents of the disk, and not just tourists passing through. From two recent surveys, Sestito and colleagues amassed a library of roughly 5,000 metal-poor stars. A few hundred of them appear to be permanent denizens of the disk. Another group sifted through about 500 stars identified by another survey, finding that about 1 in 10 of these stars lie flat in circular, sunlike orbits. And a third research group found stars of various metallicities (and therefore various ages) moving in flat disk orbits. “This is something completely new,” said lead author Paola Di Matteo, an astronomer at the Paris Observatory.
How did these anachronisms get there? Sestito speculated that perhaps pockets of pristine gas managed to dodge all the metals expelled from supernovas for eons, then collapsed to form stars that looked deceptively old. Or the disk may have started taking shape when the halo did, nearly 1 billion years ahead of schedule.
To see which was more probable, he connected with Tobias Buck, a researcher at the Leibniz Institute for Astrophysics in Potsdam, Germany, who specializes in crafting digital galaxy simulations. Past efforts had generally produced halos first and disks second, as expected. But these were relatively low-resolution efforts.
Buck increased the crispness of his simulations by about a factor of 10. At that resolution, each run demanded intensive computational resources. Even though he had access to Germany’s Leibniz Supercomputing Center, a single simulation required three months of computing time. He repeated the exercise six times.
Of those six, five produced Milky Way doppelgängers. Two of those featured substantial numbers of metal-poor disk stars.
How did those ancient stars get into the disk? Simply put, they were stellar immigrants. Some of them were born in clouds that predated the Milky Way. Then the clouds just happened to deposit some of their stars into orbits that would eventually form part of the galactic disk. Other stars came from small “dwarf” galaxies that slammed into the Milky Way and aligned with an emerging disk.
The results, which the group published in November, suggest that the classic galaxy formation models were incomplete. Gas clouds do collapse into spherical halos, as expected. But stars arriving at just the right angles can kick-start a disk at the same time. “[Theorists] weren’t wrong,” Buck said. “They were missing part of the picture.”
A Violent Youth
The complications don’t end there. With Gaia, astronomers have found direct evidence of cataclysmic collisions. Astronomers assumed that the Milky Way had a hectic youth, but Helmer Koppelman, an astronomer now at the Institute for Advanced Study in Princeton, New Jersey, used the Gaia data to help pinpoint specific debris from one of the largest mergers.
Gaia’s 2018 data release fell on a Wednesday, and the mad rush to download the catalog froze its website, Koppelman recalled. He processed the data on Thursday, and by Friday he knew he was on to something big. In every direction, he saw a huge number of halo stars ping-ponging back and forth in the center of the Milky Way in the same peculiar way — a clue that they had come from a single dwarf galaxy. Koppelman and his colleagues had a brief paper ready by Sunday and followed it up with a more detailed analysis that June.
The galactic wreckage was everywhere. Perhaps half of all the stars in the inner 60,000 light-years of the halo (which extends hundreds of thousands of light-years in every direction) came from this lone collision, which may have boosted the young Milky Way’s mass by as much as 10%. “This is a game changer for me,” Koppelman said. “I expected many different smaller objects.”
The group named the incoming galaxy Gaia-Enceladus, after the Greek goddess Gaia — one of the primordial deities — and her Titan son Enceladus. Another team at the University of Cambridge independently discovered the galaxy around the same time, dubbing it the Sausage for its appearance in certain orbital charts.
When the Milky Way and Gaia-Enceladus collided, perhaps 10 billion years ago, the Milky Way’s delicate disk may have suffered widespread damage. Astronomers debate why our galactic disk seems to have two parts: a thin disk, and a thicker one where stars bungee up and down while orbiting the galactic center. Research led by Di Matteo now suggests that Gaia-Enceladus exploded much of the disk, puffing it up during the collision. “The first ancient disk formed pretty fast, and then we think Gaia-Enceladus kind of destroyed it,” Koppelman said.
Hints of additional mergers have been spotted in bundles of stars known as globular clusters. Diederik Kruijssen, an astronomer at Heidelberg University in Germany, used galaxy simulations to train a neural network to scrutinize globular clusters. He had it study their ages, makeup, and orbits. From that data, the neural network could reconstruct the collisions that assembled the galaxies. Then he set it loose on data from the real Milky Way. The program reconstructed known events such as Gaia-Enceladus, as well as an older, more significant merger that the group has dubbed Kraken.
In August, Kruijssen’s group published a merger lineage of the Milky Way and the dwarf galaxies that formed it. They also predicted the existence of 10 additional past collisions that they’re hoping will be confirmed with independent observations. “We haven’t found the other 10 yet,” Kruijssen said, “but we will.”
All these mergers have led some astronomers to suggest that the halo may be made almost exclusively of immigrant stars. Models from the 1960s and ’70s predicted that most Milky Way halo stars should have formed in place. But as more and more stars have been identified as galactic interlopers, astronomers may not need to assume that many, if any, stars are natives, said Di Matteo.
A Still-Growing Galaxy
The Milky Way has enjoyed a relatively quiet history in recent eons, but newcomers continue to stream in. Stargazers in the Southern Hemisphere can spot with the naked eye a pair of dwarf galaxies called the Large and Small Magellanic Clouds. Astronomers long believed the pair to be our steadfast orbiting companions, like moons of the Milky Way.
Then a series of Hubble Space Telescope observations between 2006 and 2013 found that they were more like incoming meteorites. Nitya Kallivayalil, an astronomer at the University of Virginia, clocked the clouds as coming in hot at about 330 kilometers per second — nearly twice as fast as had been predicted.
When a team led by Jorge Peñarrubia, an astronomer at the Royal Observatory of Edinburgh, crunched the numbers a few years later, they concluded that the speedy clouds must be extremely hefty — perhaps 10 times bulkier than previously thought.
“It’s been surprise after surprise,” Peñarrubia said.
Various groups have predicted that the unexpectedly beefy dwarfs might be dragging parts of the Milky Way around, and this year Peñarrubia teamed up with Petersen to find proof.
The problem with looking for galaxy-wide motion is that the Milky Way is a raging blizzard of stars, with astronomers looking outward from one of the snowflakes. So Peñarrubia and Petersen spent most of lockdown figuring out how to neutralize the motions of the Earth and the sun, and how to average out the motion of halo stars so that the halo’s outer fringe could serve as a stationary backdrop.
When they calibrated the data in this way, they found that the Earth, the sun, and the rest of the disk in which they sit are lurching in one direction — not toward the Large Magellanic Cloud’s current position, but toward its position around a billion years ago (the galaxy is a lumbering beast with slow reflexes, Petersen explained). They recently detailed their findings in Nature Astronomy.
The sliding of the disk against the halo undermines a fundamental assumption: that the Milky Way is an object in balance. It may spin and slip through space, but most astronomers assumed that after billions of years, the mature disk and the halo had settled into a stable configuration.
Peñarrubia and Petersen’s analysis proves that assumption wrong. Even after 14 billion years, mergers continue to sculpt the overall shape of the galaxy. This realization is just the latest change in how we understand the great stream of milk across the sky.
“Everything we thought we knew about the future and the history of the Milky Way,” said Petersen, “we need a new model to describe that.”
BPN14770, co-developed by Tetra Therapeutics and UB, improved language and daily functioning in Fragile X Syndrome patients during phase 2 clinical trial.
A new drug discovered through a research collaboration between the University at Buffalo and Tetra Therapeutics took a major step toward becoming a first-in-class treatment for Fragile X Syndrome, a leading genetic cause of autism.
The drug, BPN14770, achieved positive topline results in a phase 2 clinical study. The innovative treatment improved cognitive function in adult male patients with Fragile X Syndrome.
Fragile X Syndrome – a genetic disorder for which there is no cure – is the most commonly known cause of inherited intellectual disability, according to the Centers for Disease Control and Prevention.
“We are very excited about the results of this study,” said Mark Gurney, PhD, founder and chief executive officer of Tetra Therapeutics. “In addition to being safe and well tolerated, treatment with BPN14770 led to significant cognitive improvement, specifically in the language domains, and we also saw a clinically meaningful benefit in overall daily functioning. These findings validate our approach to treating this disease through a mechanism that addresses a core deficit in the disorder.”
The research was conducted at Rush University Medical Center by principal investigator and pediatric neurologist Elizabeth Berry-Kravis, MD, PhD. Funding was provided by the FRAXA Research Foundation, a nonprofit dedicated to financing Fragile X Syndrome research.
Preclinical investigation of BPN14770 was completed through a collaboration between UB School of Pharmacy and Pharmaceutical Sciences faculty members James M. O’Donnell, PhD, dean and professor, and Ying Xu, MD, PhD, research associate professor, and biotechnology company Tetra Therapeutics.
The drug inhibits the activity of phosphodiesterase‐4D, an enzyme that plays a key role in memory formation, learning, neuroinflammation and traumatic brain injury. Previous studies found that BPN14770 has the potential to promote the maturation of connections among neurons, which are impaired in patients with Fragile X Syndrome.
“The collaboration with Tetra Therapeutics has been interesting and productive, combining our lab’s expertise in preclinical pharmacology and theirs in drug discovery and development,” said O’Donnell. “Seeing years of research lead to a successful trial for treatment of this serious genetic disorder is quite rewarding.”
BPN14770’s potential to improve cognitive and memory function could also translate to treatments for Alzheimer’s disease, developmental disabilities, traumatic brain injury and schizophrenia.
Tetra Therapeutics, a wholly owned subsidiary of Shionogi & Co., Ltd., is a clinical stage biotechnology company developing a portfolio of therapeutic products that will bring clarity of thought to people suffering from Fragile X Syndrome, Alzheimer’s disease, traumatic brain injury and other brain disorders. Tetra uses structure-guided drug design to discover mechanistically novel, allosteric inhibitors of the phosphodiesterase 4 (PDE4) enzymes, a family of enzymes that play key roles in memory formation, learning, neuroinflammation and traumatic brain injury. Tetra Therapeutics is headquartered in Grand Rapids, Michigan. For more information, please visit the company’s website.
New research from The Australian National University (ANU) shows palm cockatoos, renowned for their human-like musical drumming behaviour, are threatened with extinction.
According to co-author Professor Rob Heinsohn, the “animal kingdom’s match for Ringo Starr or Phil Collins” is facing rapidly declining population numbers.
“These shy and elusive birds, iconic to Cape York Peninsula in Far North Queensland, fashion thick drum sticks from branches, grip them with their feet and bang them rhythmically on the tree trunk, all the while displaying to females,” Professor Heinsohn said.
“Sadly, palm cockatoos have one of the slowest breeding rates of any bird, and our study shows the population is not producing enough young to replace the birds that die.”
The research used data from a long-term monitoring project together with new genetic information to work out how connected the scattered birds are on Cape York, and how well the good breeders compensate for those that fail to reproduce.
“Even best case scenarios show that the overall population will go down by more than a half in 49 years, the equivalent of three generations for the birds,” lead author Dr Miles Keighley said.
“This fast rate of decline means that the palm cockatoos qualify as ‘endangered’ under International Union for Conservation of Nature criteria.”
ANU researchers will work closely with the Queensland government to change the official conservation status of palm cockatoos.
“Long-lived birds like palm cockatoos, especially those that live in remote areas, are incredibly hard to study,” Professor Heinsohn said.
“We have worked very hard for over 20 years to understand the population trends. We used computer simulation techniques that allow us to look into the future – it’s a bit like having a crystal ball. But it only works if you have good data that tells you how the birds are tracking here and now.
“Palm cockatoos are very special birds. No other animal apart from humans fashions its own musical instrument, let alone creates its own rhythm.
“This only occurs among the palm cockatoos of Cape York Peninsula, adding extra impetus for protecting them and reversing the worrying downward trend.”
UC study shows that the pandemic negatively affected both preventive screening and patient outcomes.
A recent study led by University of Cincinnati Cancer Center researchers shows the impact the pandemic had on lung cancer screening, which experts say could be bad for both screening programs in general and for the overall well-being of patients. The article appears on the website of the Journal of the American College of Surgeons in advance of print.
Robert Van Haren, MD, assistant professor of surgery at UC, a UC Health thoracic surgeon and corresponding author on the study, says low-dose radiation CT scans have been shown to catch lung cancer earlier. He adds that lung cancer is the leading cause of cancer death in the U.S., but if it’s detected early, it has cure rates as high as 90%. UC created the first lung cancer screening program in the region, Van Haren adds.
CT scans combine a series of X-ray images taken from different angles around the body and then use computer processing to create images of “slices” of the bones, blood vessels and soft tissues inside the body. These images provide more detailed information than plain X-rays do.
Van Haren explains that like many programs, the COVID-19 pandemic caused a shutdown for the lung cancer screening program, but researchers wanted to find out how much of an impact that shutdown had on overall numbers of patients screened as well as cancer diagnoses.
He says that, nationally, diagnoses for many conditions, like appendicitis, heart attack and stroke, decreased during the pandemic and that evidence from the United Kingdom showed nearly a 5% increase in lung cancer deaths due to delaying a diagnosis during the pandemic.
The team used a database of patient information and outcomes to compare monthly average screenings between January 2017 and February 2020 against the COVID-19 shutdown period of March 2020 to July 2020.
The most concerning thing we found was that suspicious places in the lungs that could be cancerous increased after we reopened. This means that if the shutdown never occurred, we could have potentially found and treated issues earlier.
– Robert Van Haren, MD
“When low-dose radiation CT scans were stopped on March 13, 2020, 818 screening visits were canceled,” he says. “We began gradually reopening on May 5 and then fully opened again on June 1. Total monthly CT scans and new patient monthly scans significantly decreased during the COVID-19 period we analyzed, and new patient scans have remained low despite resuming full operations.
“The most concerning thing we found was that patients with lung nodules, or suspicious places in the lungs that could be cancerous, increased after we reopened. This means that if the shutdown never occurred, we could have potentially found and treated issues earlier.”
Van Haren adds it is sometimes difficult to get patients that qualify for lung cancer screening to participate in the first place. To qualify, patients must be 55 to 80 years old and have smoked at least one pack of cigarettes per day for 30 years or two packs of cigarettes a day for 15 years.
“Lung cancer screening was approved in the last several years, and a large number of patients who are eligible already do not get screened. So, when we had to cancel new patient appointments, we lost momentum for some of these patients who could benefit from lung cancer screening,” he says.
“COVID-19 caused a significant disruption in lung cancer screening, leading to a decrease in new patients screened and an increased proportion of suspicious nodules once screening resumed,” he adds. “By using lung cancer and our screening program as a model, this early analysis shows the consequences related to the pandemic for both screening programs and cancer care. We hope that it can provide some insight into how we deal with operations as the pandemic continues.”
UC archaeologists unlock secrets of ancient Greece.
Archaeology Magazine says the 2015 discovery of an ancient Greek warrior’s tomb by University of Cincinnati archaeologists is among the top-10 finds of the past decade.
In its January-February issue, the magazine hails the startling discovery of the tomb of the Griffin Warrior by UC archaeologists Sharon Stocker and Jack Davis as one of the most influential Bronze Age archaeological finds of the past 50 years. The UC College of Arts and Sciences researchers continue to learn secrets at Pylos that are rewriting the history of ancient Greece.
UC’s research was among Archaeology Magazine’s top-10 list that included the discovery of Richard III’s grave in Leicester, England; the discovery of early hominids in South Africa and the mystery of the HMS Erebus and HMS Terror, which disappeared while exploring the arctic in the 1840s.
The 3,500-year-old warrior was named for the mythological figure emblazoned on an ivory plaque found along with weapons, armor and jewelery.
The husband and wife team have been continuing a legacy of archaeological discovery at UC dating back to the late Carl Blegen’s work at Pylos and Troy in the 1930s.
Davis, head of UC’s Department of Classics, was honored last year with a gold medal for archaeological achievement, its highest award, from the Archaeological Institute of America for his work in the Mediterranean.
Stocker, a senior research associate, supervised the painstaking excavations at Pylos.
Among the treasures was an exquisitely carved sealstone depicting mortal combat that has been hailed as a masterpiece of Bronze Age art. The artwork is so extraordinary that the popular BBC history show “Civilisations” featured the piece during its season premiere in 2018.
“It forces us to rethink everything we thought we knew about this moment in history,” show host Simon Schama says.
UC researchers found 1,500 objects from in the tomb, from combs and mirrors to gold rings and swords.
“The grave of the Griffin Warrior has all of the artifacts you would expect a warrior to have accumulated during his lifetime. This is the first time we can understand what the complete warrior kit looked like,” Stocker told “Civilisations.”
But UC’s researchers were only getting started. In 2018 in the vicinity of the tomb of the Griffin Warrior, Stocker and Davis made another incredible discovery of two beehive-shaped Bronze Age tombs lined with gold leaf.
These princely tombs overlooking the Mediterranean Sea contained cultural artifacts and jewelry that could help historians fill in gaps in our knowledge of early Greek civilization.
A gold ring depicts two bulls flanked by sheaves of grain, identified as barley by a paleobotanist who consulted on the project. An agate sealstone features two lion-like creatures called genii standing upright on clawed feet. They carry a serving vase and incense burner, a tribute for the altar before them featuring a sprouting sapling between horns of consecration. Above them is a 16-pointed star similar to the one inlaid on another bronze and gold artifact in the grave.
The results, which show that ultrafast atomic motions are the first step in forming a magnetic state, could lead to faster and more efficient data storage devices.
Light-driven reactions, which rely on moving electrons to convert photons into energy, are at the heart of many vital processes in both nature and technology. In the 1980s, scientists discovered that in certain materials, the combined effects of electronic and atomic motions during this process can even give rise to magnetism, offering a path forward for creating a new generation of data-storing devices. But until now, researchers weren’t sure exactly how this phenomenon, called photomagnetism, played out.
“The quest to understand and control the order of physical processes during this reaction has been in vain because it all happens incredibly fast,” says Eric Collet, a physicist at the Rennes Institute of Physics (IPR) in France. “It’s like the famous chicken-and-egg paradox: No one could definitively say whether the electrons are first causing the atomic changes or vice versa.”
Now, using an X-ray laser at the Department of Energy’s SLAC National Accelerator Laboratory, a team led by Collet and IPR scientist Marco Cammarata has solved this decades-old question, showing that it’s the light-induced atomic rearrangements that kick the electron transfer into action. Their results, published in Nature Chemistry earlier this month, will help in the development of more efficient photomagnetic materials. More broadly, their results showcase the ability of ultrafast X-ray science to disentangle structural and electronic dynamics, which is of prime interest for understanding a multitude of physical, chemical and biological phenomena that rely on charge transfer.
The experiment involved tiny photomagnetic crystals made of cobalt and iron, synthesized by chemists at the Institute of Molecular Chemistry and Materials of Orsay in France (ICMMO), in combination with theoretical calculations carried out at the Institute of Condensed Matter Chemistry of Bordeaux in France (ICMCB) and the Lebanese German University. At SLAC’s Linac Coherent Light Source (LCLS), researchers used a laser to initiate a reaction in the crystals, followed by an ultrafast X-ray laser flash that produced snapshots of how the crystals responded over the first few millionths of a billionth of a second – the timescale on which electrons move across a molecule.
This technique allowed the researchers to create movies of how the sample’s atoms rearranged and how electrons were transferred between its cobalt and iron atoms, showing that the reaction begins with an ultrafast electronic excitation that drives atomic motions around the cobalt atom.
Cammarata says, “This reorganization destabilizes the electronic state of the system, which ultimately causes the transfer of electrons between cobalt and iron atoms, generating a magnetic state. Our data are also very valuable for developing advanced quantum-mechanical calculations that help reveal the physical driving forces at play.”
To follow up, the team hopes to use the same technique on other more complex systems and use other colors of laser light to kickstart the reaction in order to provide additional tests of the quantum models.
“This research is a big step towards understanding how the molecular deformation and electron transfer processes occur,” Collet says. “It could help us design new materials to enhance the reaction to light and improve the efficiency of the process.” Applications include improved solar energy conversion, light-driven chemical catalysis and ultrafast data storage devices.
LCLS is a DOE Office of Science user facility. This research was supported in part by Rennes Métropole and Région Bretagne in France, the French National Research Agency, the French National Center for Scientific Research and the European Regional Development Fund.
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