Normal view

There are new articles available, click to refresh the page.
Today — 23 November 2024Science

Tweaking non-neural brain cells can cause memories to fade

23 November 2024 at 12:00

“If we go back to the early 1900s, this is when the idea was first proposed that memories are physically stored in some location within the brain,” says Michael R. Williamson, a researcher at the Baylor College of Medicine in Houston. For a long time, neuroscientists thought that the storage of memory in the brain was the job of engrams, ensembles of neurons that activate during a learning event. But it turned out this wasn’t the whole picture.

Williamson’s research investigated the role astrocytes, non-neuron brain cells, play in the read-and-write operations that go on in our heads. “Over the last 20 years the role of astrocytes has been understood better. We’ve learned that they can activate neurons. The addition we have made to that is showing that there are subsets of astrocytes that are active and involved in storing specific memories,” Williamson says in describing a new study his lab has published.

One consequence of this finding: Astrocytes could be artificially manipulated to suppress or enhance a specific memory, leaving all other memories intact.

Read full article

Comments

© Ed Reschke

Yesterday — 22 November 2024Science

Ancient fish-trapping network supported the rise of Maya civilization

22 November 2024 at 18:40

On the eve of the rise of the Maya civilization, people living in what’s now Belize turned a whole wetland into a giant network of fish traps big enough to feed thousands of people.

We already know that the Maya turned swamps into breadbaskets by draining and building raised blocks of land for maize fields. However, a recent survey of a wetland in what’s now Belize suggests that the rise of the Maya civilization was fueled not just by maize but by tons of fish every year. University of New Hampshire archaeologist Eleanor Harrison-Buck and her colleagues recently mapped a network of channels and ponds for trapping fish, built just before the Maya civilization rose to prominence.

Fish in a barrel

Harrison-Buck and her fellow archeologists used drones and Google Earth data to map 108 kilometers of ancient channels that zigzag across 42 square kilometers of wetland in Belize’s Crooked Tree Wildlife Sanctuary. The result is a network of channels and ponds that looks remarkably like the fish traps found farther south in Bolivia, built several centuries after the ones at Crooked Tree. Radiocarbon dating of material buried in the bottom of one channel suggests that the network has been around for at least 4,000 years.

Read full article

Comments

© Fernando Flores

Our Universe is not fine-tuned for life, but it’s still kind of OK

22 November 2024 at 18:30

Physicists including Robert H. Dickle and Fred Hoyle have argued that we are living in a universe that is perfectly fine-tuned for life. Following the anthropic principle, they claimed that the only reason fundamental physical constants have the values we measure is because we wouldn’t exist if those values were any different. There would simply have been no one to measure them.

But now a team of British and Swiss astrophysicists have put that idea to test. “The short answer is no, we are not in the most likely of the universes,” said Daniele Sorini, an astrophysicist at Durham University. “And we are not in the most life-friendly universe, either.” Sorini led a study aimed at establishing how different amounts of the dark energy present in a universe would affect its ability to produce stars. Stars, he assumed, are a necessary condition for intelligent life to appear.

But worry not. While our Universe may not be the best for life, the team says it’s still pretty OK-ish.

Read full article

Comments

© Sololos

A former Orion manager has surprisingly credible plans to fly European astronauts

22 November 2024 at 17:41

It would be easy to be cynical about a German-French startup named The Exploration Company, which aims to build an increasingly sophisticated lineup of spaceships that could one day launch astronauts into orbit.

After all, European space startups don't have the greatest track record, and even with billions of dollars, one of the world's leading aerospace companies, Boeing, has failed so far to deliver a fully space-worthy human vehicle. Space is hard; human spaceflight is harder. So when a European startup shows up with grandiose plans, one's natural inclination might be to dismiss them.

That's more or less how I felt before I spoke with the founder of The Exploration Company, Hélène Huby, this week. She was surprisingly frank about the difficulties in pulling this off and shrewd about her political assessment of why now might just be the time for a new generation of European spacecraft.

Read full article

Comments

© Betty Laura Zapata/Bloomberg via Getty Images

Russian ballistic missile attack on Ukraine portends new era of warfare

22 November 2024 at 16:02

Two days ago, Russian President Vladimir Putin announced a change in the country's policy for employing nuclear weapons in conflict. Then, on Thursday, Russia attacked the Ukrainian city of Dnipro with a new type of ballistic missile capable of one day delivering multiple nuclear warheads to distant targets with little warning.

Putin says his ballistic missile attack on Ukraine is a warning to the West.

These events are just part of what has been a week of escalation in the war between Russia and Ukraine. In recent days, Ukraine fired US-made ATACMS tactical ballistic missiles and UK-supplied Storm Shadow missiles at targets in Russian territory for the first time. This followed approval by President Joe Biden for Ukraine to use US-provided longer-range missiles against Russian targets. Previously, Ukraine was only permitted to use them on its own territory.

Read full article

Comments

© Dimitar Dilkoff/AFP via Getty Images

Rocket Report: Next Vulcan launch slips into 2025; Starship gets a green light

22 November 2024 at 12:00

Welcome to Edition 7.20 of the Rocket Report! This is a super-long version of the newsletter because we did not publish last week, and there is just a ton of launch news of late. Also, I want to note that next week's report will appear a day early, on Wednesday, due to the Thanksgiving holiday. Speaking of which, you all have our thanks for reading and sharing the Rocket Report with others.

On a completely unrelated note, Rocket Lab has had some amazing mission names over the years. But this weekend's "Ice AIS Baby" launch is probably the best. I always appreciate their effort to find non-vanilla names and find a way to stop, collaborate, and listen.

Please subscribe using the box below (the form will not appear on AMP-enabled versions of the site). Each report will include information on small-, medium-, and heavy-lift rockets as well as a quick look ahead at the next three launches on the calendar.

Read full article

Comments

© Don Pettit/NASA

Surgeons remove 2.5-inch hairball from teen with rare Rapunzel syndrome

By: Beth Mole
21 November 2024 at 22:02

After a month of unexplained bouts of stomach pain, an otherwise healthy 16-year-old girl arrived at the emergency department of Massachusetts General Hospital actively retching and in severe pain.

A CT scan showed nothing unusual in her innards, and her urine and blood tests were normal. The same was found two weeks prior, when she had arrived at a different hospital complaining of stomach pain. She was discharged home with instructions to take painkillers, a medication for peptic ulcers, and another to prevent nausea and vomiting. The painkiller didn't help, and she didn't take the other two medications.

Her pain worsened, and something was clearly wrong. When she arrived at Mass General, her stomach was tender, and her heart rate was elevated. When doctors tried to give her a combination of medications for common causes of abdominal pain, she immediately vomited them back up.

Read full article

Comments

© Getty | Ada Summer

We’re closer to re-creating the sounds of Parasaurolophus

21 November 2024 at 21:30

The duck-billed dinosaur Parasaurolophus is distinctive for its prominent crest, which some scientists have suggested served as a kind of resonating chamber to produce low-frequency sounds. Nobody really knows what Parasaurolophus sounded like, however. Hongjun Lin of New York University is trying to change that by constructing his own model of the dinosaur's crest and its acoustical characteristics. Lin has not yet reproduced the call of Parasaurolophus, but he talked about his progress thus far at a virtual meeting of the Acoustical Society of America.

Lin was inspired in part by the dinosaur sounds featured in the Jurassic Park film franchise, which were a combination of sounds from other animals like baby whales and crocodiles. “I’ve been fascinated by giant animals ever since I was a kid. I’d spend hours reading books, watching movies, and imagining what it would be like if dinosaurs were still around today,” he said during a press briefing. “It wasn’t until college that I realized the sounds we hear in movies and shows—while mesmerizing—are completely fabricated using sounds from modern animals. That’s when I decided to dive deeper and explore what dinosaurs might have actually sounded like.”

A skull and partial skeleton of Parasaurolophus were first discovered in 1920 along the Red Deer River in Alberta, Canada, and another partial skull was discovered the following year in New Mexico. There are now three known species of Parasaurolophus; the name means "near crested lizard." While no complete skeleton has yet been found, paleontologists have concluded that the adult dinosaur likely stood about 16 feet tall and weighed between 6,000 to 8,000 pounds. Parasaurolophus was an herbivore that could walk on all four legs while foraging for food but may have run on two legs.

Read full article

Comments

© Hongjun Lin

Before yesterdayScience

NASA is stacking the Artemis II rocket, implying a simple heat shield fix

21 November 2024 at 17:50

The Space Launch System rocket that will dispatch four astronauts on the first Moon mission in more than 50 years passed a major milestone Wednesday.

NASA said ground teams inside the Vehicle Assembly Building (VAB) at Kennedy Space Center in Florida lifted the aft assembly of the rocket's left booster onto the mobile launch platform. Using an overhead crane, teams hoisted the left aft booster assembly—already filled with pre-packed solid propellant—from the VAB transfer aisle, over a catwalk dozens of stories high and then down onto mounting posts on the mobile launcher.

This marks the start of stacking for the second SLS rocket earmarked to launch NASA's Artemis II mission and slated to send NASA astronauts Reid Wiseman, Victor Glover, Christina Koch, and Canadian astronaut Jeremy Hansen on a 10-day flight around the far side of the Moon. Artemis II will be the first crewed flight of NASA's Artemis program and the first time people fly on the SLS rocket and Orion spacecraft.

Read full article

Comments

Yes, tapping on frescoes can reveal defects

21 November 2024 at 16:25

The US Capitol building in Washington, DC, is adorned with multiple lavish murals created in the 19th century by Italian artist Constantino Brumidi. These include panels in the Senate first-floor corridors, Room H-144, and the rotunda. The crowning glory is The Apotheosis of Washington on the dome of the rotunda, 180 feet above the floor.

Brumidi worked in various mediums, including frescoes. Among the issues facing conservators charged with maintaining the Capitol building frescoes is delamination. Artists apply dry pigments to wet plaster to create a fresco, and a good fresco can last for centuries. Over time, though, the decorative plaster layers can separate from the underlying masonry, introducing air gaps. Knowing precisely where such delaminated areas are, and their exact shape, is crucial to conservation efforts, yet the damage might not be obvious to the naked eye.

Acoustician Nicholas Gangemi is part of a research group led by Joseph Vignola at the Catholic University of America that has been using laser Doppler vibrometry to pinpoint delaminated areas of the Capitol building frescoes. It's a non-invasive method that zaps the frescoes with sound waves and measures the vibrational signatures that reflect back to learn about the structural conditions. This in turn enables conservators to make very precise repairs to preserve the frescoes for future generations.

Read full article

Comments

© Nick Gangemi

Horrifying medical device malfunction: Abdominal implant erupts from leg

By: Beth Mole
21 November 2024 at 12:30

On May 7, 2011, Georgia resident Tonya Brand noticed a pain on the inside of her right thigh. As the pain grew worse in the 4- to 5-inch area of her leg, she headed to a hospital. There, doctors suspected she had a blood clot. But an ultrasound the next day failed to find one. Instead, it revealed a mysterious toothpick-sized object lodged in Brand's leg.

Over the next few weeks, the painful area became a bulge, and on June 17, Brand put pressure on it. Unexpectedly, the protrusion popped, and a 1.5-inch metal wire came poking out of her leg, piercing her skin.

The piece of metal was later determined to be part of a metal filter she had implanted in a vein in her abdomen more than two years earlier, in March 2009, according to a lawsuit Brand filed. The filter was initially placed in her inferior vena cava (IVC), the body's largest vein tasked with bringing deoxygenated blood from the lower body back up to the heart. The filter is intended to catch blood clots, preventing them from getting into the lungs, where they could cause a life-threatening pulmonary embolism. Brand got the IVC filter ahead of a spinal surgery she had in 2009, which could boost her risk of clots.

Read full article

Comments

© Cook Medical

Qubit that makes most errors obvious now available to customers

20 November 2024 at 20:58

We're nearing the end of the year, and there are typically a flood of announcements regarding quantum computers around now, in part because some companies want to live up to promised schedules. Most of these involve evolutionary improvements on previous generations of hardware. But this year, we have something new: the first company to market with a new qubit technology.

The technology is called a dual-rail qubit, and it is intended to make the most common form of error trivially easy to detect in hardware, thus making error correction far more efficient. And, while tech giant Amazon has been experimenting with them, a startup called Quantum Circuits is the first to give the public access to dual-rail qubits via a cloud service.

While the tech is interesting on its own, it also provides us with a window into how the field as a whole is thinking about getting error-corrected quantum computing to work.

Read full article

Comments

© Quantum Circuits

Why Aztec “death whistles” sound like human screams

20 November 2024 at 19:37

Archaeologists have discovered numerous ceramic or clay whistles at Aztec sites, dubbed "death whistles" because of their distinctive skull shapes. A new paper published in the journal Communications Psychology examines the acoustical elements of the unique shrieking sounds produced by those whistles, as well as how human listeners are emotionally affected by the sounds. The findings support the hypothesis that such whistles may have been used in Aztec religious rituals or perhaps as mythological symbols.

Archaeologists unearthed the first Aztec death whistles, also known as ehecachichtlis, in 1999 while excavating the Tlatelolco site in Mexico City. They found the body of a sacrificial victim, a 20-year-old male who had been beheaded, at the base of the main stairway of a temple dedicated to the wind god Ehecatl. The skeleton was clutching two ceramic skull-shaped whistles, one in each hand, along with other artifacts. More skull whistles were subsequently found, and they've found their way into popular culture. For instance, in Ghostbusters: Afterlife (2021), Egon Spengler had such a whistle in his secret laboratory collection.

Scholars have puzzled over the purpose of the skull whistles, although given the dearth of concrete evidence, most suggestions are highly speculative. One hypothesis is that it was used in battle, with hundreds of warriors blowing their whistles simultaneously as a battle cry. Music archaeologist Arnd Adje Both has dismissed that idea, suggesting instead that the whistle's purpose was more likely tied to ceremonial or religious practices, like human sacrifice. Yet another hypothesis proposes that the whistles were intended as symbols of a deity. The skull shape, for instance, might allude to the Aztec god of the underworld, Mictlantecuhtli.

Read full article

Comments

© Sascha Frühholz

SpaceX just got exactly what it wanted from the FAA for Texas Starship launches

20 November 2024 at 17:52

A day after SpaceX launched its Starship rocket for the sixth time, the company received good news from the Federal Aviation Administration regarding future launch operations from its Starbase facility in South Texas.

In a draft version of what is known as an "Environmental Assessment," the FAA indicated that it will grant SpaceX permission to increase the number of Starship launches in South Texas to 25 per year from the current limit of five. Additionally, the company will likely be allowed to continue increasing the size and power of the Super Heavy booster stage and Starship upper stage.

"FAA has concluded that the modification of SpaceX’s existing vehicle operator license for Starship/Super Heavy operations conforms to the prior environmental documentation, consistent with the data contained in the 2022 PEA, that there are no significant environmental changes, and all pertinent conditions and requirements of the prior approval have been met or will be met in the current action," the federal agency stated in its conclusion.

Read full article

Comments

© SpaceX

Cracking the recipe for perfect plant-based eggs

An egg is an amazing thing, culinarily speaking: delicious, nutritious, and versatile. Americans eat nearly 100 billion of them every year, almost 300 per person. But eggs, while greener than other animal food sources, have a bigger environmental footprint than almost any plant food—and industrial egg production raises significant animal welfare issues.

So food scientists, and a few companies, are trying hard to come up with ever-better plant-based egg substitutes. “We’re trying to reverse-engineer an egg,” says David Julian McClements, a food scientist at the University of Massachusetts Amherst.

That’s not easy, because real eggs play so many roles in the kitchen. You can use beaten eggs to bind breadcrumbs in a coating, or to hold together meatballs; you can use them to emulsify oil and water into mayonnaise, scramble them into an omelet or whip them to loft a meringue or angel food cake. An all-purpose egg substitute must do all those things acceptably well, while also yielding the familiar texture and—perhaps—flavor of real eggs.

Read full article

Comments

© Nico De Pasquale Photography via Getty

The key moment came 38 minutes after Starship roared off the launch pad

20 November 2024 at 04:57

SpaceX launched its sixth Starship rocket Tuesday, proving for the first time that the stainless steel ship can maneuver in space and paving the way for an even larger, upgraded vehicle slated to debut on the next test flight.

The only hiccup was an abortive attempt to catch the rocket's Super Heavy booster back at the launch site in South Texas, something SpaceX achieved on the previous flight on October 13. The Starship upper stage flew halfway around the world, reaching an altitude of 118 miles (190 kilometers) before plunging through the atmosphere for a pinpoint slow-speed splashdown in the Indian Ocean.

The sixth flight of the world's largest launcher—standing 398 feet (121.3 meters) tall—began with a lumbering liftoff from SpaceX's Starbase facility near the US-Mexico border at 4 pm CST (22:00 UTC) Tuesday. The rocket headed east over the Gulf of Mexico, propelled by 33 Raptor engines clustered on the bottom of its Super Heavy first stage.

Read full article

Comments

© SpaceX.

Microsoft and Atom Computing combine for quantum error correction demo

19 November 2024 at 21:00

In September, Microsoft made an unusual combination of announcements. It demonstrated progress with quantum error correction, something that will be needed for the technology to move much beyond the interesting demo phase, using hardware from a quantum computing startup called Quantinuum. At the same time, however, the company also announced that it was forming a partnership with a different startup, Atom Computing, which uses a different technology to make qubits available for computations.

Given that, it was probably inevitable that the folks in Redmond, Washington, would want to show that similar error correction techniques would also work with Atom Computing's hardware. It didn't take long, as the two companies are releasing a draft manuscript describing their work on error correction today. The paper serves as both a good summary of where things currently stand in the world of error correction, as well as a good look at some of the distinct features of computation using neutral atoms.

Atoms and errors

While we have various technologies that provide a way of storing and manipulating bits of quantum information, none of them can be operated error-free. At present, errors make it difficult to perform even the simplest computations that are clearly beyond the capabilities of classical computers. More sophisticated algorithms would inevitably encounter an error before they could be completed, a situation that would remain true even if we could somehow improve the hardware error rates of qubits by a factor of 1,000—something we're unlikely to ever be able to do.

Read full article

Comments

© Atom Computing

Scientist behind superconductivity claims ousted

19 November 2024 at 17:46

University of Rochester physicist Ranga Dias made headlines with his controversial claims of high-temperature superconductivity—and made headlines again when the two papers reporting the breakthroughs were later retracted under suspicion of scientific misconduct, although Dias denied any wrongdoing. The university conducted a formal investigation over the past year and has now terminated Dias' employment, The Wall Street Journal reported.

“In the past year, the university completed a fair and thorough investigation—conducted by a panel of nationally and internationally known physicists—into data reliability concerns within several retracted papers in which Dias served as a senior and corresponding author,” a spokesperson for the University of Rochester said in a statement to the WSJ, confirming his termination. “The final report concluded that he engaged in research misconduct while a faculty member here.”

The spokesperson declined to elaborate further on the details of his departure, and Dias did not respond to the WSJ's request for comment. Dias did not have tenure, so the final decision rested with the Board of Trustees after a recommendation from university President Sarah Mangelsdorf. Mangelsdorf had called for terminating his position in an August letter to the chair and vice chair of the Board of Trustees, so the decision should not come as a surprise. Dias' lawsuit claiming that the investigation was biased was dismissed by a judge in April.

Ars has been following this story ever since Dias first burst onto the scene with reports of a high-pressure, room-temperature superconductor, published in Nature in 2020. Even as that paper was being retracted due to concerns about the validity of some of its data, Dias published a second paper in Nature claiming a similar breakthrough: a superconductor that works at high temperatures but somewhat lower pressures. Shortly afterward, that paper was retracted as well. As Ars Science Editor John Timmer reported previously:

Dias' lab was focused on high-pressure superconductivity. At extreme pressures, the orbitals where electrons hang out get distorted, which can alter the chemistry and electronic properties of materials. This can mean the formation of chemical compounds that don't exist at normal pressures, along with distinct conductivity. In a number of cases, these changes enabled superconductivity at unusually high temperatures, although still well below the freezing point of water.

Dias, however, supposedly found a combination of chemicals that would boost the transition to superconductivity to near room temperature, although only at extreme pressures. While the results were plausible, the details regarding how some of the data was processed to produce one of the paper's key graphs were lacking, and Dias didn't provide a clear explanation.

The ensuing investigation cleared Dias of misconduct for that first paper. Then came the second paper, which reported another high-temperature superconductor forming at less extreme pressures. However, potential problems soon became apparent, with many of the authors calling for its retraction, although Dias did not.

Read full article

Comments

© YouTube/SciTech Publishing

Novo Nordisk sells hit weight-loss drug in China—at fraction of US price

By: Beth Mole
19 November 2024 at 17:10

Patients in China will be able to purchase the blockbuster weight-loss drug Wegovy for 1,400 yuan, or about $193, just a fraction of the US list price of $1,349, according to media reports.

The price in China is in line with pricing elsewhere outside of the US. As Sen. Bernie Sanders (I-Vt.) noted in a September Senate hearing, Wegovy, made by Novo Nordisk, is sold for $265 in Canada, $186 in Denmark, $137 in Germany, and just $92 in the United Kingdom. In the hearing, Sanders and other senators grilled Novo Nordisk CEO Lars Jørgensen on the "outrageously high prices" in the US of Wegovy and the company's other popular GLP-1 drug, Ozempic, used for diabetes.

"What we are dealing with today is not just an issue of economics, it is not just an issue of corporate greed. It is a profound moral issue," Sanders said in opening remarks about the prices of the highly effective drugs.

Read full article

Comments

© Getty | Michael Siluk

❌
❌