Experimental, simulation results reveal how coaxial, co-rotating rotors may lead to a quieter hover — ScienceDaily

Imagine a silent helicopter stealthily moving troops and supplies around a future battlefield. U.S. Army researchers look to helicopter noise reduction technology as a top priority in aircraft design.

At the U.S. Army Combat Capabilities Development Command, now known as DEVCOM, Army Research Laboratory, researchers collaborated with Uber and the University of Texas at Austin to investigate the acoustic properties of electric vertical takeoff and landing aircraft, which use distributed electric propulsion to power flight.

These eVTOL vehicles may aid the Army with important tasks such as aerial surveillance and cargo transport; however, they feature smaller rotors than traditional helicopters. As a result, eVTOL rotors may emit a different sound signature that researchers will have to take into consideration.

“The noise you hear from these smaller rotors is generated through fundamentally different physical mechanisms,” said Dr. George Jacobellis, Army research engineer at the laboratory’s Vehicle Technology Directorate. “Traditional modeling techniques

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Cereal, olive and vine pollen reveal market integration in Ancient Greece — ScienceDaily

In the field of economics, the concept of a market economy is largely considered a modern phenomenon. Influential economists such as Karl Marx and Max Weber, for example, argued that although markets existed in antiquity, economies in which structures of production and distribution responded to the laws of supply and demand developed only as recently as the 19th century. A recent study by an international team of researchers, including Adam Izdebski of the Max Planck Institute for the Science of Human History, uses palynology — the study of pollen remains extracted from cored sediments — to challenge this belief and provide evidence for an integrated market economy existing in ancient Greece.

Market integration began earlier than assumed

Using publicly available data from the European Pollen Database, as well as data from other investigators, researchers analyzed pollen assemblages from 115 samples taken from six sites in southern Greece to measure landscape

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Sea Angels and Sea Butterflies Reveal Climate Change Consequences

These winged water-dwellers are sea angels, floating marine slugs that may be the “canary in the coal mine” for severe ocean acidification caused by modern global warming.

Sea angels and their fluttering counterparts, sea butterflies, are pteropods. Pteropods first evolved in the early Cretaceous period, sharing the planet with dinosaurs and ammonites. The marine slugs are ancient and remarkably resilient; they have survived periods of major global extinctions and environmental changes, according to a study published in October 2020 in the journal Proceedings of the National Academy of Sciences. In addition, they are the only living creature of their kind with a solid fossil record, so they are uniquely situated to help researchers determine the effects of global change on the marine environment.

Modern global warming is rapidly accelerating and creating new challenges for these creatures. As higher concentrations of carbon dioxide build up in the ocean and the

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Megalodon nurseries reveal world’s largest shark had a soft side

The enormous, extinct shark Megalodon probably doesn’t make you think of parenting and playdates. But a growing body of evidence suggests that these massive marine predators nurtured their babies by raising them in nurseries, and scientists just added five potential Megalodon nurseries to the list. 



a bird flying over a body of water: Megalodon, the biggest predatory shark of all time, watched over its young as many modern sharks do — by raising them in defined geographic areas known as nurseries.


© Provided by Live Science
Megalodon, the biggest predatory shark of all time, watched over its young as many modern sharks do — by raising them in defined geographic areas known as nurseries.

These baby-shark grounds are showing up all over. Scientists reported in 2010 that they had identified a Megalodon nursery in Panama. Recently, another team of researchers described a new Megalodon nursery site in northeastern Spain; fossils of fully grown sharks and youngsters were found together, with most of the fossils belonging to juveniles and newborns. 

Those same scientists also analyzed data from eight other sites — from 16 million to 3

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Computer mouse movements may reveal appetite for risk-taking

Nov. 24 (UPI) — A person’s proclivity for risk-taking can be sussed out of the subtle movements of a computer mouse, according to a new study published Tuesday in the journal Proceedings of the National Academy of Sciences.

For the study, researchers tracked the movement of the computer mouse as study participants selected between two possible gambling bets, one safe and one risky.

How participants moved their mouse prior to making their selection allowed researchers to accurately predict how the participants would respond to similar risk choices.

The researchers found participants who moved their mouse toward the safe bet before selecting the riskier play were more risk-averse than their choice suggested.

Similarly, participants who nudged the mouse in the direction of the risky bet before playing it safe were found be surprisingly willing to take on risk.

“We could see the conflict people were feeling making the choice through their

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Scientists’ atomic resolution protein models reveal new details about protein binding — ScienceDaily

Knowing precisely where proteins are frustrated could go a long way toward making better drugs.

That’s one result of a new study by Rice University scientists looking for the mechanisms that stabilize or destabilize key sections of biomolecules.

Atom-scale models by Rice theorist Peter Wolynes, lead author and alumnus Mingchen Chen and their colleagues at the Center for Theoretical Biological Physics show that not only are some specific frustrated sequences in proteins necessary to allow them to function, locating them also offers clues to achieve better specificity for drugs.

That knowledge could also help design drugs with fewer side effects, Wolynes said.

The team’s open-access study appears in Nature Communications.

The atom-scale models zero in on the interactions within possible binding sites rather than the vast majority of the interactions in proteins that guide their folding. The finer resolution models allow the incorporation of co-factors like chemically active ligands,

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Memories create ‘fingerprints’ that reveal how the brain is organized — ScienceDaily

While the broad architecture and organization of the human brain is universal, new research shows how the differences between how people reimagine common scenarios can be observed in brain activity and quantified. These unique neurological signatures could ultimately be used to understand, study, and even improve treatment of disorders such as Alzheimer’s disease.

“When people imagine similar types of events, each person does it differently because they have different experiences,” said Feng (Vankee) Lin, Ph.D., R.N. “Our research demonstrates that we can decode the complex information in the human brain related to everyday life and identify neural ‘fingerprints’ that are unique to each individual’s remembered experience.” Lin is an associate professor in the University of Rochester Del Monte Institute for Neuroscience and co-author of the study which appears in the journal Nature Communications.

In the study, researchers asked 26 participants to recall common scenarios, such as driving, attending a

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‘Dueling Dinosaurs’ fossil, hidden from science for 14 years, could finally reveal its secrets

For more than a decade, paleontologists have speculated about a single fossil that preserves skeletons of two of the world’s most famous dinosaurs, Tyrannosaurus rex and Triceratops. Not only are the bones arranged as they once were in life, but the dinosaurs are practically intertwined.

Each specimen is among the best of its kind ever found. Together, the pair—nicknamed the “Dueling Dinosaurs”—present a paleontological mystery: Did the beasts just happen to be entombed together by chance, perhaps as carcasses caught on the same river sandbar? Or had they been locked in mortal combat? Nobody has been able to study the fossil to find out.

The Dueling Dinosaurs fossil may represent a lethal struggle between a Triceratops and a juvenile T. rex, shown here in this artist’s reconstruction of prehistoric Montana.

Illustration by Anthony Hutchings

But that’s about to change. After years of legal battles that left the fossil locked

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Could a Gigantic Lunar Telescope Reveal the Very First Stars?

A Hubble deep space image showing some of the oldest known galaxies.

A Hubble deep space image showing some of the oldest known galaxies.
Image: Hubble/NASA/ESA

A team of astronomers is reviving an idea that NASA sidelined a decade ago, in which a huge observatory would be installed on the Moon. Dubbed the “Ultimately Large Telescope,” the facility would easily outperform every other telescope in its class and spot objects that are predicted by theory but have never been seen.

A large liquid-mirror telescope installed on the lunar surface could perform a task that no other telescope can: searching for the signs of the first stars in the universe. Even the very powerful, upcoming James Webb Space Telescope, which is scheduled to launch on October 31, 2021, will not be able to see the earliest stars.

Such is the contention of astronomers from the University of Texas at Austin, who have detailed their argument in a paper set to be published

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Ancient zircon minerals from Mars reveal the elusive internal structure of the red planet — ScienceDaily

The uranium-bearing mineral zircon is an abundant constituent of Earth’s continental crust, providing information about the age and origin of the continents and large geological features such as mountain chains and giant volcanoes. But unlike Earth, Mars’s crust is not evolved and is compositionally similar to the crust found under the Earth’s oceans, where zircon is rare. Therefore, zircon is not expected to be a common mineral on Mars.

“We were quite surprised and excited when we found so many zircons in this martian meteorite. Zircon are incredible durable crystals that can be dated and preserve information that tell us about their origins. Having access to so many zircons is like opening a time window into the geologic history of planet,” describes Professor Martin Bizzarro from the GLOBE Institute, who led the study.

The team investigated the ancient Martian meteorite NWA 7533, dubbed “Black Beauty,” which was discovered in the

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