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These hornets break down alcohol so fast that they can’t get drunk

29 October 2024 at 21:38

Many animals, including humans, have developed a taste for alcohol in some form, but excessive consumption often leads to adverse health effects. One exception is the Oriental hornet. According to a new paper published in the Proceedings of the National Academy of Sciences, these hornets can guzzle seemingly unlimited amounts of ethanol regularly and at very high concentrations with no ill effects—not even intoxication. They pretty much drank honeybees used in the same experiments under the table.

“To the best of our knowledge, Oriental hornets are the only animal in nature adapted to consuming alcohol as a metabolic fuel," said co-author Eran Levin of Tel Aviv University. "They show no signs of intoxication or illness, even after chronically consuming huge amounts of alcohol, and they eliminate it from their bodies very quickly."

Per Levin et al., there's a "drunken monkey" theory that predicts that certain animals well-adapted to low concentrations of ethanol in their diets nonetheless have adverse reactions at higher concentrations. Studies have shown that tree shrews, for example, can handle concentrations of up to 3.8 percent, but in laboratory conditions, when they consumed ethanol in concentrations of 10 percent or higher, they were prone to liver damage.

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© Eran Levin/Tel Aviv University

Graphene-enhanced ceramic tiles make striking art

28 October 2024 at 18:58

In recent years, materials scientists experimenting with ceramics have started adding an oxidized form of graphene to the mix to produce ceramics that are tougher, more durable, and more resistant to fracture, among other desirable properties. Researchers at the National University of Singapore (NUS) have developed a new method that uses ultrasound to more evenly distribute graphene oxide (GO) in ceramics, according to a new paper published in the journal ACS Omega. And as a bonus, they collaborated with an artist who used the resulting ceramic tiles to create a unique art exhibit at the NUS Museum—a striking merger of science and art.

As reported previously, graphene is the thinnest material yet known, composed of a single layer of carbon atoms arranged in a hexagonal lattice. That structure gives it many unusual properties that hold great promise for real-world applications: batteries, super capacitors, antennas, water filters, transistors, solar cells, and touchscreens, just to name a few.

In 2021, scientists found that this wonder material might also provide a solution to the fading of colors of many artistic masterpieces. For instance, several of Georgia O'Keeffe's oil paintings housed in the Georgia O'Keeffe Museum in Santa Fe, New Mexico, have developed tiny pin-sized blisters, almost like acne, for decades. Conservators have found similar deterioration in oil-based masterpieces across all time periods, including works by Rembrandt.

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© Daria Andreeva and Delia Prvački.

Study: DNA corroborates “Well-man” tale from Norse saga

25 October 2024 at 15:00

A 12th-century Norse saga tells of an invading army from the south razing a castle stronghold and throwing a dead body into the well to render the water undrinkable. Human remains believed to be those of this so-called "Well-man" were discovered in the 1930s, providing valuable potential outside confirmation of the tale. Scientists have now sequenced the DNA of those remains, and while they could not prove once and for all that the remains are those of the Well-man, their findings are consistent with that identification, according to a new paper published in the journal iScience.

Much of what we know about early Norse and Icelandic history comes from the sagas, many of which were written by scholars centuries after the events described—most likely based on oral traditions or earlier now-lost manuscripts. One notable exception is the Sverris Saga, which covers the reign of King Sverre Sigurdsson (1151–1240 CE), a tumultuous period marked by warring factions all vying to claim the throne. Norse scholars think that at least part of this saga was written contemporaneously at the king's request, and it contains detailed descriptions of many battles and speeches and a large cast of characters.

King Sverre's claim to the throne was that he was the son of King Sigurd Munn, killed in 1155 CE by his brother. Sverre's men were known as "Birkenbeiner" because their legwear and shoes were made of birch bark. Among the rival factions were the "Bagleres" from southern Norway. In 1197, King Sverre was spending the winter in Bergen in his stronghold, Sverresborg Castle. Bagler fighters snuck into the castle via a secret door and plundered the place, burning all the homes within the castle walls. That's when they threw a dead man down the local drinking well, subsequently filling the well with boulders.

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© Åge Hojem NTNU Vitenskapsmuseet/CC BY-SA

For the strongest disc golf throws, it’s all in the thumbs

23 October 2024 at 21:15

When Zachary Lindsey, a physicist at Berry College in Georgia, decided to run an experiment on how to get the best speed and torque while playing disc golf (aka Frisbee golf), he had no trouble recruiting 24 eager participants keen on finding science-based tips on how to improve their game. Lindsey and his team determined the optimal thumb distance from the center of the disc to increase launch speed and distance, according to a new paper published in the journal AIP Advances.

Disc golf first emerged in the 1960s, but "Steady" Ed Hendrick, inventor of the modern Frisbee, is widely considered the "father" of the sport since it was he who coined and trademarked the name "disc golf" in 1975. He and his son founded their own company to manufacture the equipment used in the game. As of 2023, the Professional Disc Golf Association (PDGA) had over 107,000 registered members worldwide, with players hailing from 40 countries.

A disc golf course typically has either nine or 18 holes or targets, called "baskets." There is a tee position for starting play, and players take turns throwing discs until they catch them in the basket, similar to how golfers work toward sinking a golf ball into a hole. The expected number of throws required of an experienced player to make the basket is considered "par."

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© Drew Teasley

Meet the winners of Nikon’s 2024 photomicrography contest

22 October 2024 at 21:24

A stunning image of differentiated mouse brain tumor cells has won the 2024 Nikon Small World photomicrography contest, yielding valuable insight into how degenerate diseases like Alzheimer's and ALS can arise from disruption in the cytoskeleton of brain cells. The image was taken by Bruno Cisterna, with assistance from Eric Vitriol, both with Augusta University in Georgia.

"One of the main problems with neurodegenerative diseases is that we don't fully understand what causes them,” Cisterna said in a statement. “To develop effective treatments, we need to figure out the basics first. Our research is crucial for uncovering this knowledge and ultimately finding a cure. Differentiated cells could be used to study how mutations or toxic proteins that cause Alzheimer's or ALS alter neuronal morphology, as well as to screen potential drugs or gene therapies aimed at protecting neurons or restoring their function.”

It's the 50th anniversary of Nikon's annual contest, which was founded back in 1974 "to showcase the beauty and complexity of things seen through the light microscope." Photomicrography involves attaching a camera to a microscope (either an optical microscope or an electron microscope) so that the user can take photographs of objects at very high resolutions. British physiologist Richard Hill Norris was one of the first to use it for his studies of blood cells in 1850, and the method has increasingly been highlighted as art since the 1970s. There have been many groundbreaking technological advances in the ensuing decades, particularly with the advent of digital imaging methods.

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© Bruno Cisterna & Eric Vitrol/Nikon Small World

How the Malleus Maleficarum fueled the witch trial craze

17 October 2024 at 21:11

Between 1400 and 1775, a significant upsurge in witch trials swept across early modern Europe, resulting in the execution of an estimated 40,000–60,000 accused witches. Historians and social scientists have long studied this period in hopes of learning more about how large-scale social changes occur. Some have pointed to the invention of the printing press and the publication of witch-hunting manuals—most notably the highly influential Malleus Maleficarum—as a major factor, making it easier for the witch-hunting hysteria to spread across the continent.

The abrupt emergence of the craze and its rapid spread, resulting in a pronounced shift in social behaviors—namely, the often brutal persecution of suspected witches—is consistent with a theory of social change dubbed "ideational diffusion," according to a new paper published in the journal Theory and Society. There is the introduction of new ideas, reinforced by social networks, that eventually take root and lead to widespread behavioral changes in a society.

The authors had already been thinking about cultural change and the driving forces by which it occurs, including social contagion—especially large cultural shifts like the Reformation and the Counter-Reformation, for example. One co-author, Steve Pfaff, a sociologist at Chapman University, was working on a project about witch trials in Scotland and was particularly interested in the role the Malleus Maleficarum might have played.

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© Wellcome Images/CC-BY-4.0

What we can learn from animals about death and mortality

16 October 2024 at 11:15

Human beings live every day with the understanding of our own mortality, but do animals have any concept of death? It's a question that has long intrigued scientists, fueled by reports of ants, for example, appearing to attend their own"funerals"; chimps gathering somberly around fallen comrades; or a mother whale who carried her dead baby with her for two weeks in an apparent show of grief.

Philosopher Susana Monsó is a leading expert on animal cognition, behavior and ethics at the National Distance Education University (UNED) in Madrid, Spain. She became interested in the topic of how animals experience death several years ago while applying for a grant and noted that there were a number of field reports on how different animal species reacted to death. It's an emerging research field called comparative thanatology, which focuses on how animals react to the dead or dying, the physiological mechanisms that underlie such reactions, and what we can learn from those behaviors about animal minds.

"I could see that there was a new discipline that was emerging that was very much in need of a philosophical approach to help it clarify its main concepts," she told Ars. "And personally, I was turning 30 at the time and became a little bit obsessed with death.  So I wanted to think a lot about death and maybe come to fear it less through philosophical reflection on it."

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© Princeton University Press

Remains of Andrew “Sandy” Irvine found on Everest

11 October 2024 at 16:54

In June 1924, a British mountaineer named George Leigh Mallory and a young engineering student named Andrew "Sandy" Irvine set off for the summit of Mount Everest and disappeared—two more casualties of a peak that has claimed over 300 lives to date. Mallory's body was found in 1999, but Irvine's was never found—until now. An expedition led by National Geographic Explorer and professional climber Jimmy Chin—who won an Oscar for the 2019 documentary Free Solo, which he co-directed—has located a boot and a sock marked with Irvine's initials at a lower altitude than where Mallory's body had been found.

The team took a DNA sample from the remains, and members of the Irvine family have volunteered to compare DNA test results to confirm the identification. “It’s an object that belonged to him and has a bit of him in it,” Irvine’s great-niece Julie Summers told National Geographic. "It tells the whole story about what probably happened. I'm regarding it as something close to closure.”

As previously reported, Mallory is the man credited with uttering the famous line "because it's there" in response to a question about why he would risk his life repeatedly to summit Everest. Mallory had already been to the mountain twice before the 1924 expedition: once in 1921 as part of a reconnaissance expedition to produce the first accurate maps of the region and again in 1922. He was forced to turn back on all three attempts.

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© Jimmy Chin

Breakdancers at risk for “headspin hole,” doctors warn

10 October 2024 at 22:30

Breakdancing has become a global phenomenon since it first emerged in the 1970s, even making its debut as an official event at this year's Summer Olympics. But hardcore breakers are prone to injury (sprains, strains, tendonitis), including a bizarre condition known as "headspin hole" or "breakdance bulge"—a protruding lump on the scalp caused by repeatedly performing the power move known as a headspin. A new paper published in the British Medical Journal (BMJ) describes one such case that required surgery to redress.

According to the authors, there are very few published papers about the phenomenon; they cite two in particular. A 2009 German study of 106 breakdancers found that 60.4 percent of them experienced overuse injuries to the scalp because of headspins, with 31.1 percent of those cases reporting hair loss, 23.6 percent developing head bumps, and 36.8 percent experiencing scalp inflammation. A 2023 study of 142 breakdancers reported those who practiced headspins more than three times a week were much more likely to suffer hair loss.

So when a male breakdancer in his early 30s sought treatment for a pronounced bump on top of his head, Mikkal Bundgaard Skotting and Christian Baastrup Søndergaard of Copenhagen University Hospital in Denmark seized the opportunity to describe the clinical case study in detail, taking an MRI, surgically removing the growth, and analyzing the removed mass.

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Octopus suckers inspire new tech for gripping objects underwater

9 October 2024 at 19:00

Over the last few years, Virginia Tech scientists have been looking to the octopus for inspiration to design technologies that can better grip a wide variety of objects in underwater environments. Their latest breakthrough is a special switchable adhesive modeled after the shape of the animal's suckers, according to a new paper published in the journal Advanced Science.

“I am fascinated with how an octopus in one moment can hold something strongly, then release it instantly. It does this underwater, on objects that are rough, curved, and irregular—that is quite a feat,” said co-author and research group leader Michael Bartlett. "We’re now closer than ever to replicating the incredible ability of an octopus to grip and manipulate objects with precision, opening up new possibilities for exploration and manipulation of wet or underwater environments.”

As previously reported, there are several examples in nature of efficient ways to latch onto objects in underwater environments, per the authors. Mussels, for instance, secrete adhesive proteins to attach themselves to wet surfaces, while frogs have uniquely structured toe pads that create capillary and hydrodynamic forces for adhesion. But cephalopods like the octopus have an added advantage: The adhesion supplied by their grippers can be quickly and easily reversed, so the creatures can adapt to changing conditions, attaching to wet and dry surfaces.

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© Alex Parrish for Virginia Tech

Archaeologists found an ancient Egyptian observatory

8 October 2024 at 12:15

A few years ago, Egyptian archaeologists discovered what they thought were the ruins of an ancient Egyptian temple dating back to the sixth century BCE. Subsequent finds at the site indicate that the structure was actually an astronomical observatory, deemed the first and largest such structure yet found, according to Egypt's Ministry of Tourism and Antiquities.

The L-shaped structure was found within a larger complex called the Temple of Buto (a later Greek name), known to the ancient Egyptians as Per-Wadjet and located east of Alexandria in the Nile Delta. It's now called Tell El Fara'in ("Hill of the Pharaohs"). Buto was once a sacred site dedicated to the goddess Wadjet, believed to be the matron and protector of lower Egypt, who took on a cobra form. Buto was well-known for its temple and the oracle of Wadjet, with an annual festival held there in her honor.

There were archaeological excavations of the site in the 1960s and 1980s, revealing a palace dating back to the Second Dynasty, as well as six Greek bathhouses. An Egyptian team began fresh excavations a few years ago. In 2022, they uncovered a hall at the southwestern end of the temple, with the remains of three papyrus-shaped columns aligned on a north-south axis. They also found  engraved stone fragments and a limestone painting of a bird's head wearing a white crown within two feathers.

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© Ministry for Tourism and Antiquities

How London’s Crystal Palace was built so quickly

4 October 2024 at 20:29

London's Great Exhibition of 1851 attracted some 6 million people eager to experience more than 14,000 exhibitors showcasing 19th-century marvels of technology and engineering. The event took place in the Crystal Palace, a 990,000-square-foot building of cast iron and plate glass originally located in Hyde Park. And it was built in an incredible 190 days. According to a recent paper published in the International Journal for the History of Engineering and Technology, one of the secrets was the use of a standardized screw thread, first proposed 10 years before its construction, although the thread did not officially become the British standard until 1905.

“During the Victorian era there was incredible innovation from workshops right across Britain that was helping to change the world," said co-author John Gardner of Anglia Ruskin University (ARU). "In fact, progress was happening at such a rate that certain breakthroughs were perhaps never properly realized at the time, as was the case here with the Crystal Palace. Standardization in engineering is essential and commonplace in the 21st century, but its role in the construction of the Crystal Palace was a major development."

The design competition for what would become the Crystal Palace was launched in March 1850, with a deadline four weeks later, and the actual, fully constructed building opened on May 1, 1851. The winning design, by Joseph Paxton, wasn't chosen until quite late in the game after numerous designs had been rejected—most because they were simply too far above the 100,000-pound budget.

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© Philip Henry Delamotte/Public Domain

Strange “biotwang” ID’d as Bryde’s whale call

3 October 2024 at 20:36

In 2014, researchers monitoring acoustic recordings from the Mariana Archipelago picked up an unusual whale vocalization with both low- and high-frequency components. It seemed to be a whale call, but it sounded more mechanical than biological and has since been dubbed a "biotwang."

Now a separate team of scientists has developed a machine-learning model to scan a dataset of recordings of whale vocalizations from various species to help identify the source of such calls. Combining that analysis with visual observations allowed the team to identify the source of the biotwang: a species of baleen whales called Bryde's (pronounced "broodus") whales. This should help researchers track populations of these whales as they migrate to different parts of the world, according to a recent paper published in the journal Frontiers in Marine Science.

Marine biologists often rely on a powerful tool called passive acoustic monitoring for long-term data collection of the ocean's acoustic environment, including whale vocalizations. Bryde's whale calls tend to be regionally specific, per the authors. For instance, calls in the eastern North Pacific are pretty well documented, with frequencies typically falling below 100 Hz, augmented by harmonic frequencies as high as 400 Hz. Far less is known about the sounds made by Bryde's whales in the western and central North Pacific, since for many years there were only three known recordings of those vocalizations—including a call dubbed "Be8" (starting at 45 Hz with multiple harmonics) and mother-calf calls.

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© NOAA Fisheries/Adam Ü (NMFS MMPA-ESA Permit #14097)

Despite stricter regulations, Europe has issues with tattoo ink ingredients

2 October 2024 at 19:02

Recently, chemists at Binghamton University learned that many tattoo inks in the US contain different pigments than those listed, or unlisted additives. One might expect the European Union, with its stricter regulations, to have fewer issues on that score, but according to a new paper published in the journal Analyst, that's not the case, particularly for green and blue tattoo inks. Most had components that were not listed on the label, and some included banned ingredients.

"Our work cannot say anything about the safety of tattoos, but we think it's an important first step in addressing the question 'Are tattoos safe?'" said co-author John Swierk, a chemist at Binghamton University. "If we don't know what's in a bottle of tattoo ink, then we cannot figure out what might be causing an adverse event in the near and long term, whether that’s an allergic reaction or something more serious. As a team, we aren't anti-tattoo, we just believe that clients and artists have a right to know what's in the inks they are using."

As previously reported, typical tattoo ink contains one or more pigments (which give the ink its color) within a "carrier package" to help deliver the pigments into the skin. The pigments are the same as those used in paints and textiles. They can be either small bits of solids or discrete molecules, such as titanium dioxide or iron oxide (for white or rust-brown colors, respectively). As for the carrier packages, most ink manufacturers use grain or rubbing alcohol, sometimes with a bit of witch hazel added to the mix to help the skin heal after the tattooing process. There may also be other additives to adjust the viscosity and keep pigment particles suspended in the carrier package.

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© KelvynSkee/CC BY 2.0

Strange “biotwang” ID’d as Bryde’s whale call

3 October 2024 at 20:36

In 2014, researchers monitoring acoustic recordings from the Mariana Archipelago picked up an unusual whale vocalization with both low- and high-frequency components. It seemed to be a whale call, but it sounded more mechanical than biological and has since been dubbed a "biotwang."

Now a separate team of scientists has developed a machine-learning model to scan a dataset of recordings of whale vocalizations from various species to help identify the source of such calls. Combining that analysis with visual observations allowed the team to identify the source of the biotwang: a species of baleen whales called Bryde's (pronounced "broodus") whales. This should help researchers track populations of these whales as they migrate to different parts of the world, according to a recent paper published in the journal Frontiers in Marine Science.

Marine biologists often rely on a powerful tool called passive acoustic monitoring for long-term data collection of the ocean's acoustic environment, including whale vocalizations. Bryde's whale calls tend to be regionally specific, per the authors. For instance, calls in the eastern North Pacific are pretty well documented, with frequencies typically falling below 100 Hz, augmented by harmonic frequencies as high as 400 Hz. Far less is known about the sounds made by Bryde's whales in the western and central North Pacific, since for many years there were only three known recordings of those vocalizations—including a call dubbed "Be8" (starting at 45 Hz with multiple harmonics) and mother-calf calls.

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© [CDATA[NOAA Fisheries/Adam (NMFS MMPA-ESA Permit #14097)]]

Despite stricter regulations, Europe has issues with tattoo ink ingredients

2 October 2024 at 19:02

Recently, chemists at Binghamton University learned that many tattoo inks in the US contain different pigments than those listed, or unlisted additives. One might expect the European Union, with its stricter regulations, to have fewer issues on that score, but according to a new paper published in the journal Analyst, that's not the case, particularly for green and blue tattoo inks. Most had components that were not listed on the label, and some included banned ingredients.

"Our work cannot say anything about the safety of tattoos, but we think it's an important first step in addressing the question 'Are tattoos safe?'" said co-author John Swierk, a chemist at Binghamton University. "If we don't know what's in a bottle of tattoo ink, then we cannot figure out what might be causing an adverse event in the near and long term, whether that’s an allergic reaction or something more serious. As a team, we aren't anti-tattoo, we just believe that clients and artists have a right to know what's in the inks they are using."

As previously reported, typical tattoo ink contains one or more pigments (which give the ink its color) within a "carrier package" to help deliver the pigments into the skin. The pigments are the same as those used in paints and textiles. They can be either small bits of solids or discrete molecules, such as titanium dioxide or iron oxide (for white or rust-brown colors, respectively). As for the carrier packages, most ink manufacturers use grain or rubbing alcohol, sometimes with a bit of witch hazel added to the mix to help the skin heal after the tattooing process. There may also be other additives to adjust the viscosity and keep pigment particles suspended in the carrier package.

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© [CDATA[KelvynSkee/CC BY 2.0]]

Study: Cats in little crocheted hats shed light on feline chronic pain

27 September 2024 at 18:02

Our feline overlords aren't particularly known for obeying commands from mere humans, which can make it difficult to study their behaviors in controlled laboratory settings. So a certain degree of ingenuity is required to get usable results—like crocheting adorable little hats for kitties taking part in electroencephalogram (EEG) experiments. That's what researchers at the University of Montreal in Quebec, Canada, did to learn more about assessing chronic pain in cats—and they succeeded. According to their recent paper published in the Journal of Neuroscience Methods, it's the first time scientists have recorded the electrical activity in the brains of conscious cats.

According to the authors, one-quarter of adult cats suffer from osteoarthritis and chronic pain that worsens with age. There are currently limited treatment options, namely, non-steroidal anti-inflammatory drugs, which can have significant side effects for the cats. An injectable monoclonal antibody tailored for cats has recently been developed to neutralize excessive nerve growth factor, but other alternative treatment options like supplements and regenerative medicine have yet to be tested. Nor has the effectiveness of certain smells or lighting in altering pain perception in felines been tested.

That was the Montreal team's primary objective for their experiments. Initially, they tried to place electrodes on the heads of 11 awake adult cats with osteoarthritis, but the cats kept shaking off the electrodes.

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These 3D-printed pipes inspired by shark intestines outperform Tesla valves

26 September 2024 at 17:52

Scientists at the University of Washington have re-created the distinctive spiral shapes of shark intestines in 3D-printed pipes in order to study the unique fluid flow inside the spirals. Their prototypes kept fluids flowing in one preferred direction with no need for flaps to control that flow and performed significantly better than so-called "Tesla valves," particularly when made of soft polymers, according to a new paper published in the Proceedings of the National Academy of Sciences.

As we've reported previously, in 1920, Serbian-born inventor Nikola Tesla designed and patented what he called a "valvular conduit": a pipe whose internal design ensures that fluid will flow in one preferred direction, with no need for moving parts, making it ideal for microfluidics applications, among other uses. The key to Tesla's ingenious valve design is a set of interconnected, asymmetric, tear-shaped loops.

In his patent application, Tesla described this series of 11 flow-control segments as being made of "enlargements, recessions, projections, baffles, or buckets which, while offering virtually no resistance to the passage of fluid in one direction, other than surface friction, constitute an almost impassable barrier to its flow in the opposite direction." And because it achieves this with no moving parts, a Tesla valve is much more resistant to the wear and tear of frequent operation.

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© [CDATA[Sarah L. Keller/University of Washington]]

Tailwinds don’t help “everesting” cyclists

25 September 2024 at 16:05
man in bicycle in cycling shorts and helmet

Enlarge / Physicist Martin Bier in an aerodynamic tuck, a cycling position that reduces wind resistance. (credit: Martin Bier)

Many avid bicyclists these days have hopped onto the "everesting" bandwagon, in which one rides up and down the same mountain route over and over until the total distance of one's ascents matches the elevation of Mount Everest: 8,848 meters or about 5.5 miles. Recently there has been debate over whether a strong tailwind could help a rider improve their time. But apparently that's not the case, according to a new paper published in the American Journal of Physics by physicist Martin Bier of East Carolina University in North Carolina.

The term "everesting" takes its name from George Mallory, grandson of the legendary 1920s mountaineer George Mallory who participated in the first three British Everest expeditions. Mallory the younger was prepping for his Everest attempt in 1994, and his training included weekend workouts involving bicycling up Mount Donna Buang in Australia many times until he had achieved the elevation of Mount Everest.

Twenty years later, another Australian cycling enthusiast, Andy van Bergen, started organizing worldwide "everesting" events. Participating cyclists would pick a hill near their homes and track each other's progress online. The events became extremely popular in 2020 after the outbreak of the COVID-19 pandemic sparked global lockdowns.

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