Ankle sprain is one of the most common musculoskeletal injuries, particularly in sports like netball, basketball and football where jumping, landing on one foot and sudden direction changes are part of the game.

Ankle sprains can be painful, debilitating and may result in ongoing ankle problems. In fact, people with a history of a previous ankle sprain are more likely to sprain an ankle again in future.

Prevention is key. In an effort to reduce sprain risk, many people look for "high-top" shoes, where the section around the side of the shoe (also known as the "collar") extends up closer to the ankle.

But what does the research say? Do high-top shoes actually reduce your sprain risk?

High-tops don't always help – and can sometimes harm

Plenty of research exists on this topic but unraveling the truth is complicated by inconsistency between studies. Researchers may have different ways of investigating the issue, of measuring the shoes success, or even different ways of defining a "high-top" shoe.

For example, the reported difference in collar height between "high-top" to "low-top" shoes was considerable, ranging from 4.3 to 8.5 cm (1.7 to 3.3 inch) across different studies.

That said, the trend in the current research literature suggests the ankle protection provided by high-top shoes may not be enough to significantly reduce sprain risk while playing sport.

In fact, this design may also reduce athletic performance, and increase the risk of ankle sprain in some people.

Research does support the idea high-top shoes provide good stability when outside forces may cause an ankle sprain when the person is stationary (for example, when a person standing still is knocked from the side and starts to topple over, putting stress on the ankle).

However, once you start moving it's a different story. In fact, some research suggests high-top shoes may even increase the risk of ankle sprain in some activities.

This may be because these shoes can change the way we use the muscles in our ankles and legs.

Specifically the muscles on the outside of the lower leg may start firing later and not work as strongly to stiffen the ankle when you're wearing high top shoes (compared to low top shoes).

To reduce ankle sprain risk, it is important the muscles on both sides of the legs work together at the same time.

Tellingly, delayed and weaker activation of the muscles on the outside of the lower leg is greater in people with chronic ankle instability. This finding suggests high-top shoes may not be the best choice for anyone with a history of ankle sprain.

There is also some evidence wearing high-top shoes may impede athletic performance by reducing jump height and increasing shock transmission to other parts of the body.

Getting the right fit

External supports such as tape and braces are effective in both uninjured and previously injured ankles. But they're most effective when used in combination with preventive exercise programs.

What is crucial when selecting footwear is good fit and good function. Footwear should fit the foot in length, width and depth, with a thumb's width between the end of the longest toe and the tip of the shoe. You should have enough space across the ball of the foot for it to not be pulled tight when standing.

However, around 70 percent of people are wearing shoes that are not fitted appropriately. Women and girls more often have shoes that are too narrow, and older males often wear shoes that are too long.

Ill-fitting footwear can increase falls, induce greater levels of osteoarthritis and impedes natural foot function in adults and children.

Make sure you've got the right shoe for the job. Form must suit function.

As an example, there's merit in wearing a well-fitted high-top sneaker during static, standing based activities.

However, a low-top sneaker may be more beneficial during sporting activities that require frequent stopping, jumping, sudden changes in direction or for people with a history of ankle sprains.

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A groundbreaking epidemiological study has produced the most compelling evidence yet that exposure to the chemical solvent trichloroethylene (TCE)—common in soil and groundwater—increases the risk of developing Parkinson’s disease. The movement disorder afflicts about 1 million Americans, and is likely the fastest growing neurodegenerative disease in the world; its global prevalence has doubled in the past 25 years.

The report, published today in JAMA Neurology, involved examining the medical records of tens of thousands of Marine Corps and Navy veterans who trained at Marine Corps Base Camp Lejeune in North Carolina from 1975 to 1985. Those exposed there to water heavily contaminated with TCE had a 70% higher risk of developing Parkinson’s disease decades later compared with similar veterans who trained elsewhere. The Camp Lejeune contingent also had higher rates of symptoms such as erectile dysfunction and loss of smell that are early harbingers of Parkinson’s, which causes tremors; problems with moving, speaking, and balance; and in many cases dementia. Swallowing difficulties often lead to death from pneumonia.

About 90% of Parkinson’s cases can’t be explained by genetics, but there have been hints that exposure to TCE may trigger it. The new study, led by researchers at the University of California, San Francisco (UCSF), represents by far the strongest environmental link between TCE and the disease. Until now, the entire epidemiological literature included fewer than 20 people who developed Parkinson’s after TCE exposure.

The Camp Lejeune analysis “is exceptionally important,” says Briana De Miranda, a neurotoxicologist at the University of Alabama at Birmingham who studies TCE’s pathological impacts in the brains of rats. “It gives us an extremely large population to assess a risk factor in a very carefully designed epidemiological study.”

“We had suspicions, but this is the evidence,” agrees Gary Miller, a neurotoxicologist who studies Parkinson’s disease at Columbia University. “It’s very compelling.”

TCE is a colorless liquid that readily crosses biological membranes. It turns into vapor quickly and can be absorbed by ingestion, through skin or by inhalation. It’s used today mainly in producing refrigerants and as a degreaser in heavy industry.

But in the 20th century, TCE was used for many purposes, including making decaffeinated coffee, dry cleaning, carpet cleaning, and as an inhaled surgical anesthetic for children and women in labor. TCE is highly persistent in soil and groundwater; inhalation through vapor from these hidden sources is likely the prime route of exposure today. However, it’s detectable in many foods, in up to one-third of U.S. drinking water, and in breast milk, blood, and urine.

To conduct the study, the UCSF team and colleagues elsewhere scoured Department of Veterans Affairs and Medicare health records of nearly 85,000 Marine Corps and Navy personnel who were stationed for at least 3 months at Camp Lejeune decades ago. At the time, wells on the base were contaminated from leaking underground storage tanks, industrial spills, and waste disposal sites. Water used on the base contained TCE levels more than 70 times the level allowed by the U.S. Environmental Protection Agency (EPA). Recruits could have ingested TCE in food or water, been exposed through their skin when bathing or showering, or inhaled the highly volatile compound, which was also used by the military for degreasing and cleaning metal machinery.

A capped well at Marine Corps Base Camp Lejeune. Marines who lived there even briefly have higher rates of Parkinson’s disease today. Allen Breed/AP

The researchers calculated the rate of Parkinson’s disease in the veterans and compared it with the rate in more than 72,000 veterans who lived at Marine Corps Base Camp Pendleton, a similar training ground in California where there were not high levels of TCE. By 2021, 279 of the Camp Lejeune veterans, or 0.33%, had developed Parkinson’s versus 151 of those at Camp Pendleton, or 0.21%. After adjusting for differences in age, sex, race, and ethnicity, the scientists found veterans from Camp Lejeune had a 70% higher rate of Parkinson’s disease than the Camp Pendleton group.

In the Camp Lejeune veterans, the researchers also found higher rates of symptoms known to precede the onset of the movement disorder.

Because the recruits were so young—an average age of 20—while at the training camp, the mostly male cohorts had an average age just shy of 60 when the analysis of their health records ended in 2021. That means that more Parkinson’s diagnoses may occur as most people develop the disease after age 60.

Animal studies have shown that TCE acts in an area of the midbrain responsible for movement control. It inhibits complex 1, the leading enzyme in a chain of reactions that convert food to energy in cellular organelles called mitochondria. In rodents exposed to TCE, the dopamine-generating neurons in the midbrain’s substantia nigra are destroyed, as happens in human Parkinson’s disease. Pesticides such as paraquat and rotenone that have been associated with Parkinson’s disease also leave that pathological signature in rodents.

The Camp Lejeune study’s lead author, UCSF epidemiologist Sam Goldman, conducted a small twin study published in 2012 showing that TCE exposure increased the risk of the disease in humans. That work, he says, was prompted by a published report of a cluster of Parkinson’s cases in a factory where workers were chronically and heavily exposed to TCE, which was used as a metal degreaser.

Goldman was motivated to undertake the current study in 2017. That year, the U.S. government declared that any veteran who served at Camp Lejeune in the contaminated water era and had Parkinson’s disease would be presumed to have developed it because of TCE exposure at the base, despite the scant epidemiological evidence. “I just felt … we really need to have greater certainty about this,” Goldman says.

The study did have weaknesses. For instance, just because a Marine was stationed Camp Lejeune did not guarantee that they were exposed to TCE; if that was the case, the study may actually be underestimating the link between TCE and Parkinson’s. On the other hand, it’s possible that Camp Lejeune trainees with Parkinson’s were overrepresented in the study because—thanks to the new government policy—they were increasingly seeking care through VA beginning in 2017. Indeed, when the investigators looked only at cases ascertained before that year, the increased risk of Parkinson’s was lower: 28%. However, the recruits were also younger before 2017 and less likely to have developed the disease, for which age is the leading risk factor.

In January, EPA declared that TCE presents an “unreasonable risk of injury to human health” and said it will develop a rule regulating its use. (The chemical is also a known carcinogen.) But that “really means nothing for what’s already in the environment,” De Miranda says. Mitigating against exposure is tricky, she adds, because, unlike with pesticides, underground TCE locations aren’t always documented.

“Alarmingly, TCE vapor intrusion is widespread today and ranges from an elementary school situated on top of a former chemical facility in Shanghai, China, to multimillion-dollar homes built on a previous aerospace plant in Newport Beach, California,” the authors of an accompanying editorial in JAMA Neurology write.

The new study will likely add ammunition to class action lawsuits that were launched after Congress last year enabled veterans from Camp Lejeune to sue the government for health damage they suffered from exposure to the contaminated water there decades ago. “This is increasing evidence that environmental factors are important causes of Parkinson’s disease,” Miller says. “But we are just scratching the surface. We need to continue studying this.”

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Japan plans to build a potent missile arsenal that could be configured to deliver its latent nuclear capabilities, a strategic escalation for the long-time pacifist power that will put it on a faster collision course with China.

This month, Naval News reported that Japan’s Ministry of Defense had signed four contracts with Mitsubishi Heavy Industries to design and manufacture various standoff missiles to be aimed at China and North Korea, including a US$1.29 billion contract to upgrade mass production of the Type 12 surface-to-ship missile (SSM).

The contracts also include $200 million to develop Type 12 SSM ground/air/ship-launched versions, $891.8 million for the mass production of the Hyper Velocity Gliding Projectile (HVGP), and $436 million for the development of a submarine-launched guided missile.

The Naval News report notes that the upgraded ground-launched Type 12 SSM will start production this year and enter service in 2026, with successive upgrades increasing its range from 200 to 900 and eventually 1,500 kilometers.

Japan also has two planned hypersonic weapons designs. Naval News notes that Japan’s HVGP Block 1 is slated to start production this year and has an estimated range of 500 to 900 kilometers, with two missiles mounted on a track-type launcher.

The report says the design’s Block 2A and 2B are expected to have very large bodies, with a range of 2,000 kilometers for the former and 3,000 kilometers or more for the latter. It also states that the Block 1 and Block 2A and 2B missiles are to be developed from 2023 to 2027 and 2023 to 2030, respectively.

In terms of operational use, Naval News mentions that Block 1 will be operated by the “HVGP Battalion” deployed in Kyushu. In contrast, Block 2A and 2B will be operated by “long-range guided missile units” on the northern island of Hokkaido.

Naval News notes that an extended-range submarine-launched version of the Type 12 SSM will be developed between 2023 to 2027 alongside a new submarine equipped with vertical launch systems (VLS) to fire larger missiles.

Asia Times noted in January 2023 that Japan’s investments in long-range missiles are likely driven by the limitations of its airpower against China’s recent advancements, with a strategic hope that an expanded missile arsenal will make up for the limits of its long-range strike capability.

China flaunts its hypersonic prowess in the Dongfeng-17 hypersonic glider during a military parade in Beijing in a file photo. Photo: AFP

In terms of fighter numbers, China had 2,250 fighter aircraft in 2021, with 800 of that number being 4th generation fighters. In contrast, Japan has only 244 fighters as of this year. China’s 5th generation J-20 aircraft is still under production and although Japan can buy more F-35s to match China’s J-20s, spiraling F-35 costs may limit the number of aircraft Japan can purchase.

With Japan fielding a limited number of fighters, using long-range missiles for strike missions traditionally done by manned aircraft may make strategic sense. That approach would make Japan use its limited fighters to attack only the most sensitive of targets and preserve fighter strength for air defense.

Following that approach, Japan would likely need a large arsenal of long-range missiles to deter China and North Korea. It would also require maximum independence from foreign manufacturers and need huge stockpiles to maintain a high rate of fire.

However, developing a strategic deterrent built around long-range missiles may end up impractical without the ability to deliver nuclear warheads.

Apart from making up for deficiencies in fighter numbers, Japan may seek to develop pre-emptive strike capabilities against China and North Korea’s highly-lofted missile launches and hypersonic weapons.

Asia Times noted in August 2022 that the difficulties of traditional missile defense systems such as Aegis and Patriot in engaging highly-lofted trajectory attacks may have convinced Japan to attack adversaries’ missile launch and storage facilities before an attack could be launched. Holding such facilities at risk increases the costs of a Chinese or North Korean attack on Japan, enhances deterrence and degrades attempts at coercion.

However, in acquiring multiple types of long-range missiles, Japan needs to define the mission parameters of its missile forces and if it would rely on US real-time targeting capabilities, as it currently lacks sufficient intelligence, surveillance and reconnaissance (ISR) capabilities for such launches. 

Existing missile defense systems such as Patriot and Aegis may be ineffective against highly-lofted trajectory attacks, with ballistic missiles fired at such angles ending up with very high terminal velocities, presenting a much smaller radar cross section at their point to missile defense radars that usually detect missiles from the side.

Missile defense radars may lose track of their targets when the latter hit the apex of their trajectories, then usually regain track too late for interceptor missiles to hit. Interceptor missiles also have to fly against gravity, unlike the constantly-accelerating target.

Hypersonic weapons also pose a severe challenge to existing missile defense systems.

For example, Northrop Grumman notes that hypersonic weapons skip along the upper atmosphere to achieve greater range, operate at altitudes too high or low for traditional ballistic missile defense systems to intercept, and manuever on unpredictable flight paths that significantly increase the difficulty of interception.

A pre-emptive strike may thus be one of the few effective means for Japan to counter these weapons. Meanwhile, missile defense technology such as railguns, lasers and hypersonic interceptors are still under development.

In a January 2023 article, Asia Times noted that these acquisitions could be interpreted as Japan moving to develop indigenous deterrent capabilities independent of US security guarantees.

Japan Self-Defense Forces soldiers raise the PAC-3 missile unit to a firing position. Photo: Agencies

However, it is doubtful whether the US will use nuclear weapons to defend Japan and that the constancy of US security guarantees may be undermined by US presidential elections every four years and fickle US public opinion.

However, Japan’s missile-based, pre-emptive strike capabilities may increase unpredictability and regional tensions in the Pacific. These developments will quickly bring put Japan’s evolving nuclear latency in the spotlight.

Japan has the resources, technology and scientific knowledge to assemble a nuclear weapon quickly should the US, for whatever reason, withhold or revoke its security guarantees.   

As Japan has a complete nuclear fuel cycle and, in theory, can produce fissile material for nuclear weapons, its new missiles could readily be configured as delivery vehicles for nuclear warheads, potentially becoming a nuclear triad hiding in plain sight.

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Diet sodas are not actually good for your diet, WHO guidance suggests

The discovery of 62 previously unknown satellites has put the ringed planet firmly back in the lead, with a grand total of 145 officially recognized moons. This means Big Jupe, with its paltry 92 known moons, is going to have to pull out some slick moves if it wants to retake the crown.

More importantly, though, it demonstrates the efficacy of a technique for spotting small moons around the giant planets.

By shifting and stacking images taken of the moons over several years, a team led by astronomer Edward Ashton of the Academia Sinica Institute of Astronomy and Astrophysics in Taiwan was able to find Saturnian moons down to a diameter of just 2.5 kilometers (1.55 miles).

A Cassini image of five of Saturn's moons, from left to right: Janus, Pandora, Enceladus, Rhea, and Mimas.

(NASA/JPL-Caltech/Space Science Institute)

And these newly discovered tiny moonlets are allowing astronomers to piece together Saturn's past.

It's actually fairly challenging locating small moons orbiting Jupiter and Saturn. These two planets are the largest in the Solar System, and they're very bright in the sky, especially from our point of view on Earth, from which they're always in sunlight.

This means they vastly outshine anything around them, making the detection of small, dim objects particularly tricky.

Interestingly enough, the criteria for defining a moon, or natural satellite, are fairly broad. There's no shape or mass or diameter or composition requirement; the object in question just needs to have a stable orbit around another, larger body that isn't a star. So planets, dwarf planets, and even asteroids can all have their own moons.

But it's not sufficient just to spot an object near a planet and declare that you've found a new moon. The object needs to be tracked – ideally for several orbits – so that its path can be analyzed to determine if it's stable. So while shifting and stacking can reveal faint objects, taking many such observations is needed to confirm moon status.

Here's how it works. A set of sequential images is "shifted" at the same rate a moon moves across the sky. Then, these images are stacked, a technique that amplifies signals too faint to be seen in an individual image, and makes them brighter so that scientists can see them.

The orbital paths of four of the newly discovered moons around Saturn. (UBC)

This shifting and stacking technique had been used to look for moons orbiting Uranus and Neptune; in 2019, Ashton and his colleagues used it to scan the sky around Saturn using the Canada-France-Hawaii Telescope (CFHT), locating what appeared to be previously unknown objects in the space around Saturn.

Between then and 2021, they periodically took observations for three-hour spans, shifting and stacking the resulting images to see if the objects they identified could be moons. They picked out 63 new moons, one of which was announced in 2021. Now, they have painstakingly confirmed the other 62.

"Tracking these moons makes me recall playing the kid's game Dot-to-Dot, because we have to connect the various appearances of these moons in our data with a viable orbit, but with about 100 different games on the same page and you don't know which dot belongs to which puzzle," Ashton says.

All the newly discovered moons belong to the three groups of Saturn's moons classified as "irregular". These – clustered into clumps known as Inuit, Gallic, and Norse moons – orbit the planet on large, elliptical orbits at an inclined angle with respect to the "regular" moons of Saturn.

Most of the new moons fall into the Norse group, which is the most populous and has the greatest orbital distance of the three. It also orbits in the opposite direction to Saturn's rotation.

Astronomers have interpreted these groups as evidence of collisions between moons that took place at some point in Saturn's recent past, leaving behind swarms of smaller moons.

The Norse group, according to analysis, could be what's left after the disruption of a moderately-sized irregular moon. The newly discovered moons are further evidence of this, the researchers say.

"As one pushes to the limit of modern telescopes," says astronomer Brett Gladman of the University of British Columbia in Canada, "we are finding increasing evidence that a moderate-sized moon orbiting backwards around Saturn was blown apart something like 100 million years ago."

Your move, Jupiter.

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Experiments since have shown that quantum entanglement is indeed possible and that two entangled particles can be connected over a distance. Now a new experiment further confirms it, and in a way we haven't seen before.

In the new experiment, scientists used a 30-meter-long tube cooled to close to absolute zero to run a Bell test: a random measurement on two entangled qubit (quantum bit) particles at the same time.

The test proposes a mathematical inequality which, if broken, shows that the theory of quantum mechanics holds together.

Not only does this experiment run the Bell test at longer distances than previously attempted, but it also runs it using superconducting circuits, which are expected to play a significant role in the development of quantum computers.

Because of the way the experiment is structured, with hundreds of micrometer-sized electronic circuits, a modified version could be used in several ways.

"With our approach, we can prove much more efficiently than is possible in other experimental setups that Bell's inequality is violated," says quantum physicist Simon Storz from ETH Zurich in Switzerland.

"That makes it particularly interesting for practical applications."

Those practical applications could include, for example, secure encrypted communications.

Here the Bell test experiment involves entangled qubits. (Storz et al., Nature, 2023)

Despite the challenges of constructing and fine-tuning the machine, the researchers are confident that it could be adapted to work on larger scales, too, pushing the boundaries of what we know about quantum mechanics.

"There are 1.3 [tons] of copper and 14,000 screws in our machine, as well as a great deal of physics knowledge and engineering know-how," says quantum physicist Andreas Wallraff, also from ETH Zurich.

To remove all potential loopholes from a Bell test, measurements be taken in less time than it takes for light to travel from one end to another – which proves no information has been exchanged between them.

With this setup, it took light 110 nanoseconds to travel down the tube, and the measurements were taken in just a few nanoseconds less.

Researchers used microwave photons to create the entanglement, and more than a million measurements were evaluated to show the violation of Bell's inequality.

It's the longest separation between two entangled superconducting qubits yet and shows the promise of qubit technology. The same tech demonstrated here could eventually find its way into full-scale quantum computers.

"Our work demonstrates that non-locality is a viable new resource in quantum information technology realized with superconducting circuits with potential applications in quantum communication, quantum computing, and fundamental physics," write the researchers in their published paper.

The research has been published in Nature.

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The World Gastroenterology Organization (WGO) recently published an updated guideline document, aimed at helping gastroenterologists and other physicians understand appropriate clinical applications for probiotics or prebiotics. The guideline was created with contributions from experts in gastroenterology, probiotics, and prebiotics, with the efforts co-led by experts from the International Scientific Association for Probiotics and Prebiotics (ISAPP).

To create the guideline, the experts comprehensively evaluated the evidence from randomized, controlled trials on gastrointestinal conditions, including which strain or specific prebiotic substance showed a positive effect. The guideline features a list of conditions that have positive evidence for the efficacy of probiotics and/or prebiotics.

A condition was included in the list if at least one randomized, controlled trial demonstrated a beneficial effect. The guideline also includes the level of evidence supporting benefits in each condition, based on a classification from Oxford Centre for Evidence-Based Medicine.

Prof. Francisco Guarner, MD, Ph.D., leader of the WGO project, commented, "Our goal for this project was to provide a guideline to global gastroenterologists and other health care professionals to enable them to integrate probiotics and prebiotics in an evidence-based manner into their daily work of patient care."

The conditions for which probiotics / prebiotics show benefit include some well-known ones: diarrheal conditions, irritable bowel syndrome, inflammatory bowel disease and lactose maldigestion. For infants, infantile colic and necrotizing enterocolitis are included in the list. Yet positive evidence also exists for some conditions that are not often associated with probiotic / prebiotic benefits: insulin resistance, non-alcoholic fatty liver disease, H. pylori infection, and even general health-related quality of life.

The evidence summarized in the guideline reinforces the notion that not all probiotics are equal and that positive results in trials depend on which probiotics or prebiotic substances are being tested, and at what dose.

The experts were careful to note that not all of the products shown to be effective are found in all countries. In addition, despite overall favorable evidence in the listed conditions, clinicians should not expect all probiotics or prebiotics to be effective for every person.

Dr. Mary Ellen Sanders Ph.D., ISAPP executive science officer and co-chair of the project, stated, "This guideline recognizes that actionable evidence exists for probiotic and prebiotic use in clinical practice. It is an excellent tool for health care providers to aid them in matching the probiotic or prebiotic to patient needs."

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The patient — a mechanic who was a husband and father of two — had been born with a particularly sinister gene mutation that should have doomed him to dementia before his 50th birthday.

Instead, his life had been one of remarkable resilience, bucking the script written in his genes. The cognitive impairment that should have started at age 44 stayed at bay for more than two decades. Rather than dying in his early 60s, he retired. He did eventually develop moderate dementia, and he passed away in 2019 at the age of 74.

This man is only the second patient identified with the miraculous ability to defy the devastating Alzheimer’s gene, an international team of scientists report in the journal Nature Medicine. Doctors hope the two known cases will allow researchers to develop new treatments to protect other people with Alzheimer’s disease, which affects 6.7 million people in the United States.

The researchers sifted through the man’s genome to identify a different mutation that may have helped protect him against the disease. They also used brain scans taken when he was 73 to home in on a key region that appears to have been relatively protected against the tau protein tangles that typically occur in Alzheimer’s patients.

“I think it’s important that we listen to the patients. And I think what the patients are telling us is … there is a pathway for protection,” said Joseph F. Arboleda-Velasquez, an associate scientist at Mass Eye and Ear, a Harvard teaching hospital, and one of the leaders of the study.

“These are very provocative findings, and I do think these cases have something very important to teach us about resilience to disease and the biology” of Alzheimer’s, said Gil Rabinovici, a neurologist at the University of California at San Francisco, who was not involved in the study.

“I think this raises a number of interesting questions. I don’t know that we have the answers.” 

 A genetic time bomb

For decades, neurologist Francisco Lopera at the University of Antioquia in Medellín, Colombia, has been caring for and following an extended family, many of whose members carry a tragically unlucky mutation in a gene called presenilin 1. The mutation is rare, and its effects are aggressive and predictable.

By their late 20s, people who carry the mutation have brains clogged with the hallmark amyloid plaques that characterize Alzheimer’s disease. By their mid-30s, tangles of a different protein associated with Alzheimer’s, tau, appear.

People carrying this gene begin to experience the first inklings of cognitive problems around age 44, and by 49, they have full-blown dementia. They typically die in their 60s.

In total, scientists have discovered 1,200 people out of an extended family of more than 6,000 carrying this genetic time bomb.

Yakeel T. Quiroz, director of the Familial Dementia Neuroimaging Lab at Massachusetts General Hospital, has worked with Lopera and these patients for 20 years. 

 “You meet them before they have symptoms, and you see them progress,” Quiroz said. “You get to stay around and see how they become severely demented — and how they die. There’s nothing you can do to stop it.”

But in 2019, researchers discovered a single patient, Aliria Rosa Piedrahita de Villegas, who seemed to have fended off fate.

Her memory didn’t start to decline until she was in her 70s. Scientists discovered a genetic mutation that protected her, nicknamed Christchurch. Although her brain was clogged with the characteristic amyloid plaques of Alzheimer’s, it was relatively free of the tangles of tau that are also associated with the disease.

Scientists marveled at the case but also debated its relevance. This was only one person. Was it an aberration, or a path to follow? What could this one person reveal about how to fight Alzheimer’s in the broader population? 

 A tangled target for Alzheimer’s drugs

The discovery of a second person with genetic resilience validates the quest but also deepens the mystery.

The man, whose identity is anonymous at his family’s request, doesn’t have the Christchurch gene variant. He appears to have been protected due to a mutation in a different gene called reelin.

What’s more, both patients had brains riddled with amyloid plaques, which have so far been a key target in therapies for Alzheimer’s.

Recently, drugs aimed at clearing amyloid plaques have been approved in the United States — the first beacons of hope in decades. But these drugs are far from a cure. They aim to slow the progression of the disease, but have fostered debate and criticism over whether modest benefits outweigh their risks and costs.

The woman’s lack of tau tangles supported an alternate avenue for therapeutics. When the man traveled to Massachusetts to have his brain scanned at age 73, researchers found that he had both amyloid plaques and tau tangles associated with Alzheimer’s disease. But crucially, tau was relatively limited in his entorhinal cortex, which is essential for memory.

“The possibility that just by protecting the entorhinal cortex, even if you have a lot of Alzheimer’s pathology elsewhere, you can have that protection? Wouldn’t that be amazing? That’s what’s very tantalizing,” Arboleda-Velasquez said.

Is it Alzheimer’s? Families want to know, and blood tests may offer answers.

Scientists, including those involved in the research, cautioned that the study is far from a definitive explanation of why the man’s memory was protected for years. There could be multiple contributors, rather than a single explanation.

But the possibility that a person could have a high level of protection against decline, even with a brain that is substantially affected by amyloid and tau buildup, is “intriguing,” said Inmaculada Cuchillo Ibañez, a neuroscientist at the Institute of Neurosciences at Miguel Hernández University in Alicante, Spain. She has studied the reelin protein in the brains of people with more common forms of Alzheimer’s disease.

“This suggests that this … could be critical in protecting against cognitive impairment,” Cuchillo Ibañez wrote in an email.

The researchers did find an overlap between the two different gene mutations that helped protect these individuals: Both mutations affect proteins that bind to the same receptors on the surfaces of brain cells. The scientists also found that mice that are genetically predisposed to develop tau tangles in their brains were less likely to do so when they carried the reelin gene mutation found in the man.

Understanding the possible biochemical pathways that produced protection opens up new approaches for drug development, the researchers said.

Quiroz said the man’s family members were excited that something useful had been learned from his case. Patients and researchers are both aware that the disease moves so quickly that discoveries may only benefit future generations. But Lopera said in an email that these exceptional cases point the way forward.

The two cases, he wrote, “have enormous potential to benefit the entire world population with or at risk of Alzheimer’s disease because they are showing a path to prevention and cure.” 

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The Great Oxygenation Event, which occurred around 2.4 billion years ago, was one of the biggest transformations of our planet. Before it, there was practically no oxygen in the atmosphere; after, there was.

 

Conventionally, the rise of oxygen is seen as life triumphantly terraforming a passive planet. But we’re learning now that Earth was an active participant, and it took two more big lifts of oxygen over the succeeding 2 billion years before it reached breathable levels. So which was more responsible for oxygen’s rise on Earth: the evolution of life or the evolution of the planet? Nature or nurture? And does the same answer apply to all of the rises of oxygen in Earth’s past?

 

It’s a question beyond curiosity about our past, as it also affects how we might interpret signs of life on exoplanets.

Alien Earth

For almost half of our planet's existence—the entire time before the Great Oxygenation Event, or GOE—Earth was effectively an alien planet. Apart from the obvious (the air was unbreathable), the oceans also lacked oxygen and were full of dissolved iron, while land was lethally irradiated by ultraviolet light, as the atmosphere lacked an ozone layer. Even the colour palette was alien: Land lacked the reddish hues of dirt and the greens of vegetation, while the sky was pinkish-orange due to high methane levels.

 

Life began in that alien environment, and at some point between 3.2 and 2.8 billion years ago, cyanobacteria began to use sunlight to split hydrogen from water, discarding oxygen as waste. That was a whopping 400 million to 800 million years before the GOE, roughly the same time that separates the present from the dawn of complex life.

 

“Life turned on this set of reactions that can produce oxygen, but what we know from the geological record is that didn't immediately result in huge amounts of oxygen in the atmosphere,” said Dr. Benjamin Mills of the University of Leeds.

 

Clearly, the invention of oxygen-producing photosynthesis wasn’t enough by itself to oxygenate the atmosphere.

 

Earth as oxygenator

Earth loses about 90 tons of gas—mainly hydrogen and helium—to space every day. That’s tiny compared to the mass of our atmosphere, so there’s no cause for alarm. But before the GOE, hydrogen loss to space was so massive that it left an imbalance between isotopes of hydrogen today because hydrogen escapes more easily than deuterium, its heavier isotope. That imbalance shows Earth lost the equivalent of a quarter of the water that had filled its oceans due to hydrogen loss.

 

“The mantle initially could have contained more water than it does now, and that water came out of the mantle initially in the form of hydrogen,” explained Professor Rajdeep Dasgupta of Rice University.

 

Losing hydrogen from H2O but keeping the oxygen pushed Earth toward an oxidizing environment, the same way it was developed on Mars. Mars has just enough oxygen, which was left behind after the hydrogen from its water leaked into space, to rust its surface red,

 

“There is a net oxidation of the planet, including the atmosphere, including the crust and the mantle through time,” Dasgupta said about Earth.

The complicated history of how the Earth’s atmosphere became breathable

A Delta II rocket launched the Spitzer Space Telescope two decades ago, boosting it to an Earth-trailing orbit, where it drifted away from our planet at a rate of about 15 million kilometers a year. It was the last of NASA's four "Great Observatories" put into space from 1990 to 2003.

Over its planned five-year lifetime, the infrared space telescope performed its job well, helping astronomers discover newly forming stars, observe exoplanets, and study galaxies. After more than seven years, as anticipated by scientists, the onboard supply of liquid helium ran out. Without this coolant, some of Spitzer's scientific instruments were unavailable. So its operators switched to "warm mission" mode, taking data from two of its shortwave channels.

The space telescope continued operating until about three years ago, when the spacecraft began to overheat whenever it needed to point back toward Earth for communications. By this time, as it drifted farther from Earth, it was close to being on the opposite side of the Sun. This meant that operating the telescope, and having it phone home from time to time, would irreparably damage Spitzer's remaining scientific instruments.

And so in January 2020, after more than 16 years of service, the Spitzer Space Telescope was deactivated—consigned to drift in a heliocentric orbit until the Sun's fiery expansion at the end of its life a few billion years from now.

Or was it?

A small space technology company, Rhea Space Activity, says it has a plan to resurrect Spitzer. Last week the firm said it won a $250,000 grant from the US Space Force to continue studying a robotic rescue mission for the spacecraft, which is now about two astronomical units—or twice the distance of Earth from the Sun—away.

The plan is rather audacious, but it has some serious backers, including the Smithsonian Astrophysical Observatory, the Johns Hopkins University Applied Physics Laboratory, Blue Sun Enterprises, and Lockheed Martin.

"When it comes to robotic space servicing, this would be the most ambitious thing ever done," said Shawn Usman, an astrophysicist who is the founder and chief executive of Rhea Space Activity, in an interview with Ars. "I mean, it is literally sending a satellite to the other side of the Sun to resurrect the last Great Observatory. So I think it would be pretty ambitious, but it'd be really great if we could pull it off."

The "Spitzer Resurrector" mission would be a small spacecraft that could fit into a 1-meter-by-1-meter box and be ready to launch as soon as 2026, Usman said. It would then take about three years to cruise to the telescope, during which time the spacecraft will make observations of solar flaring.

"We plan to be busy right from the start of the mission," said Howard Smith, an astronomer at the Center for Astrophysics, which is operated by Harvard University and the Smithsonian, who is involved in the proposed rescue flight.

Once the resurrector spacecraft reaches the telescope, it would fly around at a distance of 50 to 100 km to characterize Spitzer's health. Then it would attempt to establish communications with the telescope and begin to relay information back and forth between the ground and telescope. This would allow scientists to restart observations.

Rhea Space Activity, which is named after the Greek goddess and presently has fewer than 10 employees, is seeking a larger grant from the military and, ultimately, full funding for a mission expected to cost about $350 million.

"It's a very beautiful collaboration between a private space company, academic research institutions, and the US Space Force," said Giovanni Fazio, a Harvard University astronomer who was the principal investigator of the Infrared Array Camera on Spitzer.

Commercial servicing

The effort by Rhea Space is part of an emerging trend in the commercial space industry. Northrop Grumman has been developing and launching a series of "mission extension" vehicles to service satellites in geostationary orbit. Billionaire Jared Issacman is working with SpaceX and NASA to use a Crew Dragon vehicle to extend the life of the Hubble Space Telescope.

The autonomous satellite technology developed by Rhea Space could have multiple applications for moving and servicing satellites in low-Earth and geostationary orbit. It is for these in-space servicing, assembly, and manufacturing capabilities that the Department of Defense is interested. Last year the White House published a report stating that advancing government and commercial capabilities in these areas was a priority for the United States.

Usman said the company has already had discussions with NASA about the mission, and the agency is likely to sign off on a rescue attempt. The space agency would welcome the return of Spitzer not only for scientific purposes, but also to help characterize the threat of near-Earth asteroids.

But is Spitzer healthy after all this time? Two decades have passed since Spitzer launched, and the Resurrector mission will not reach it before the end of this decade.

"The solar cells may be degraded, and there may be meteorite impacts," Fazio said. "So it's an uncertainty what condition the telescope is in. But our best estimate is that it will still be in an operating condition."

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SARS-CoV-2 infection can cause lasting damage to sensory nerves, leading to symptoms of Long COVID, according to a study by researchers from multiple institutions. The study identified gene expression changes associated with neurodegeneration and pain-related pathways, highlighting the need for targeted therapeutics. The findings offer potential avenues for addressing somatosensory symptoms and developing new treatments.

COVID-19, the disease resulting from SARS-CoV-2 infection, is associated with highly variable clinical outcomes that range from asymptomatic disease to death. For those with milder infections, COVID-19 can produce respiratory infection symptoms (cough, congestion, fever) and sensory phenotypes such as headache and loss of sense of smell. In more severe cases, SARS-CoV-2 infection can affect nearly every organ and result in strokes from vascular occlusion, cardiovascular damage and acute renal failure. A substantial number of actively infected patients suffering from both mild and severe infections experience sensory-related symptoms, such as headache, visceral pain, Guillain-Barre syndrome, nerve pain and inflammation. In most patients these symptoms subside after the infection ends, but, for other patients, they can persist.

In a new study, researchers from Boston University Chobanian & Avedisian School of Medicine, Icahn School of Medicine at Mount Sinai (Icahn Mount Sinai) and New York University (NYU), have found that thousands of genes were affected by SARS-CoV-2-mediated disease even after the viral infection had been cleared. These genes were associated with neurodegeneration and pain-related pathways, suggesting lasting damage to dorsal root ganglia (spinal nerves that carry sensory messages from various receptors) that may underlie symptoms of Post-COVID Conditions also known as Long COVID.

“Several studies have found that a high proportion of Long COVID patients suffer from abnormal perception of touch, pressure, temperature, pain or tingling throughout the body. Our work suggests that SARS-CoV-2 might induce lasting pain in a rather unique way, emphasizing the need for therapeutics that target molecular pathways specific to this virus,” explains corresponding author Venetia Zachariou, PhD, Edward Avedisian Professor and chair of pharmacology, physiology & biophysics at BU Chobanian & Avedisian School of Medicine. This work was performed in collaboration with Benjamin tenOever, PhD, professor of microbiology and medicine at NYU, formerly at Icahn Mount Sinai.

Using an experimental model infected with SARS-CoV-2, the researchers studied the effects of infection on sensitivity to touch, both during active infection and well after the infection had cleared. They then compared the effects of SARS-CoV-2 to those triggered by influenza A virus infection. In the experimental model, they observed a slow but progressive increase in sensory sensitivity over time – one that differed substantially from viral control, influenza A virus, which caused quick hypersensitivity during active infection but returned to normal by the time infection was over.

According to the researchers, this model can be used to gain information on genes and pathways affected by SARS-CoV-2, providing novel information to the scientific community on gene expression changes in sensory ganglia several weeks after infection.

“We hope this study will provide new avenues for addressing somatosensory symptoms of long COVID and ME/CFS (myalgic encephalomyelitis/chronic fatigue syndrome), which are only just now beginning to be addressed by mainstream medicine. While we have begun using this information by validating one promising target in this study, we believe our now publicly available data can yield insights into many new therapeutic strategies,” adds Zachariou.

These findings appear online in the journal Science Signaling.

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• Insights may help investigators better understand gut health and the development of conditions such as inflammatory bowel disease

The human gut is inhabited by a diverse community of microbes that play a crucial role in both health and illness. Certain microorganisms are believed to be involved in the onset of inflammatory disorders, such as IBD, however, the exact process linking these microbes to the activation of the immune system and the eventual development of the disease is still not fully understood.

Researchers from Brigham and Women’s Hospital, a founding member of the Mass General Brigham healthcare system, have conducted a new study to shed light on the factors that trigger the generation of Th17 cells in the intestine. Th17 cells are a crucial subtype of cells in the gut, and this study aims to uncover some of the previously overlooked molecular mechanisms and events that lead to their differentiation in the gut.

One of those players is the purine metabolite xanthine, which is found at high levels in caffeinated foods such as coffee, tea, and chocolate. The results of the study were recently published in the journal Immunity.

“One of the concepts in our field is that microbes are required for Th17 cell differentiation, but our study suggests that there may be exceptions,” said co-lead author Jinzhi Duan, Ph.D., of the Division of Gastroenterology, Hepatology, and Endoscopy in the Department of Medicine at BWH. “We studied the underlying mechanisms of Th17 cell generation in the gut and found some surprising results that may help us to better understand how and why diseases like IBD may develop.”

While illuminating the steps leading to Th17 cell differentiation, the researchers unexpectedly discovered a role for xanthine in the gut.

“Sometimes in research, we make these serendipitous discoveries—it’s not necessarily something you sought out, but it’s an interesting finding that opens up further areas of inquiry,” said senior author Richard Blumberg, MD, of the Division of Gastroenterology,

Hepatology and Endoscopy in the Department of Medicine. “It’s too soon to speculate on whether the amount of xanthine in a cup of coffee leads to helpful or harmful effects in a person’s gut, but it gives us interesting leads to follow up on as we pursue ways to generate a protective response and stronger barrier in the intestine.”

Interleukin-17-producing T helper (Th17) cells are thought to play a key role in the intestine. The cells can help to build a protective barrier in the gut, and when a bacterial or fungal infection occurs, these cells may release signals that cause the body to produce more Th17 cells. But the cells have also been implicated in diseases such as multiple sclerosis, rheumatoid arthritis, psoriasis, and IBD.

Duan, co-lead author Juan Matute, MD, Blumberg, and colleagues used several mouse models to study the molecular events that lead to the development of Th17 cells. Surprisingly, they found that Th17 cells could proliferate even in germ-free mice or mice that had been given antibiotics wiping out bacteria. The team found that endoplasmic reticulum stress in intestinal epithelial cells drove Th17 cell differentiation through purine metabolites, such as xanthine, even in mice that did not carry microbes and with genetic signatures that suggested cells with protective properties.

The authors note that their study was limited to cells in the intestine—it’s possible that crosstalk between cells in the gut and other organs, such as the skin and lung, may have an important influence on outcomes. They also note that their study does not identify what causes Th17 cells to become pathogenic—that is, play a role in disease. They note that further exploration is needed, including studies that focus on human-IBD Th17 cells.

“While we don’t yet know what’s causing pathogenesis, the tools we have developed here may take us a step closer to understanding what causes disease and what could help resolve or prevent it,” said Blumberg.

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• Elon Musk’s revised settlement agreement with the SEC will remain in place, including the need for a “Twitter sitter,” a federal appeals court ruled on Monday.

• Musk had been trying to get the consent decree lifted, arguing that it potentially violated his constitutional rights to free speech.

• The court dismissed Musk’s claims and affirmed the prior ruling, which allowed the terms of the consent decree to remain in place.

Tesla CEO Elon Musk lost an appeal to unwind parts of a consent decree that he and the automaker struck with the Securities and Exchange Commission to settle civil securities fraud charges in 2018.

The ruling, issued Monday by a federal appeals court, affirms a prior decision from the U.S. District Court for the Southern District of New York, which issued the initial denial.

Musk has litigated with the SEC for years over the consent decree, which was revised in 2019 after the SEC charged Musk with making “false and misleading” statements in his Aug. 2018 “funding secured” tweets. The Tesla CEO said he had found a buyer to take the automaker private at $420 a share, a claim which a federal judge later found to be false.

The agreement required “pre-approval” for tweets by Musk that contained information material to Tesla, and which extended to “certain senior executives,” according to the judgment.

A February letter from Musk attorney Alex Spiro said the terms of the consent decree, which was revised in 2019, amounted to “unconstitutional” infringement of his free speech rights.

But the U.S. Court of Appeals for the Second Circuit dismissed those claims, writing that the court saw “no evidence to support Musk’s contention that the SEC has used the consent decree to conduct bad-faith, harassing investigations of his protected speech.”

The court noted that the SEC had opened “just three inquiries” into his tweets since 2018: over his “funding secured” tweet, a tweet which misstated Tesla’s annual production numbers, and a Twitter poll where Musk proposed selling 10% of his Tesla shares, according to the court filing.

Far from being “bad-faith,” the court wrote that “each tweet plausibly violated the terms of the consent decree.”

Musk’s attorneys also put forward an argument under Rule 60(b), which allows a party to reopen their case if the law or the situation has changed significantly. Musk’s legal team argued that the SEC’s methods of enforcement made compliance “substantially more onerous.”

But the court dismissed that argument as well, noting that Musk was merely required to consult with Tesla’s general counsel or an in-house securities lawyer.

Musk’s Twitter activity has been the subject of both SEC and shareholder attention. Musk was found “not liable” in a February securities fraud trial over his “funding secured” tweets. Musk has also been fending off a lawsuit involving his public boosting of the cryptocurrency dogecoin.

The court also added that if Musk had concerns about SEC oversight over his “right to tweet without even limited internal oversight,” he could have defended himself against the SEC’s charges or negotiated a different settlement. “But he chose not to do so,” the court emphasized.

“Having made that choice,” the court concluded, Musk’s team couldn’t argue “to collaterally reopen a final judgment merely because he has now changed his mind.”

“We will seek further review and continue to bring attention to the important issue of the government constraint on speech,” Musk’s attorney Spiro said in a statement to CNBC.

< Read the judgment below: >

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After a month of trying, the radar antenna on the Jupiter Icy Moons Explorer (Juice) is finally unfolded and operable. The Radar for Icy Moons Exploration (RIME) antenna failed to deploy after launch, which flight controllers blamed on an errant pin. The problem has now been solved, leaving all 10 of JUICE’s instruments in working condition as it starts the long voyage to its gas giant destination.

To move the pin, flight controllers did what the rest of us do when dealing with errant equipment: they shook it. Not being able to do that by hand, they made Juice fire its thrusters to jiggle the pin. When this produced insufficient movement, they allowed sunlight to heat the craft up – still an option while it is whipping around the inner Solar System before heading for colder climes. Multiple jolts seemed to finally do it.

“On 12 May RIME was finally jolted into life when the flight control team fired a mechanical device called a ‘non-explosive actuator’ (NEA), located in the jammed bracket,” an ESA statement announced. “This delivered a shock that moved the pin by a matter of millimeters and allowed the antenna to unfold.”

The oscillations caused by the firing of the actuator (NEA 6). The swift dampening is a sign of the antenna being fully unfolded and wobbling until it locks into its correct position.

Although this unfolded most of the antenna, one portion remained recalcitrant, until a second actuator firing solved the problem.

JUICE will not reach Jupiter until 2031, although operations may start a little earlier when it passes the asteroid 223 Rosa. To save fuel it is taking a long and winding path, including flybys of Venus, Earth, and even the Moon to steal a little of their orbital velocity. Consequently, fixing the problem of the stuck antenna was far from urgent. On the other hand, after weeks of trying one solution after another without success, fears were growing, although Juice's other instruments still looked set to provide plenty of useful data without RIME.

Nevertheless, RIME is an important part of the mission, expected to reveal subsurface structure on the target moons – Ganymede, Callisto, and Europa – to a depth of 9 kilometers (6 miles). Moreover, the European Space Agency (ESA) has a shorter history than NASA, so any failures loom larger in public, and possibly funders' perceptions. After the failure of the high-profile Beagle lander on Mars, eventually attributed to solar panels not deploying, another incomplete mission would have been a major hit to ESA’s reputation.

Fortunately, however, Juice is now more likely to be a success ESA can point to in future when seeking funding for Solar System exploration. Indeed, its collaboration with the soon-to-be-launched Europa Clipper looks like being one of the most exciting scientific missions of the next decade.

As the name suggests, the Europa Clipper will focus on the smallest of Jupiter’s four big moons, considered to be one of the best prospects for finding life beyond the Earth. Meanwhile, Juice will make only two flybys of Europa, but will visit Ganymede and Callisto 12 and 21 times respectively. The capacity to compare what Juice learns about this pair with the Europa Clipper’s observations of their smaller sibling could prove more useful than either on their own. 

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It’s looking increasingly likely that El Niño is on its way. In turn, this could have major implications for weather patterns worldwide as well as some worrying consequences for the climate crisis.

The latest NOAA update has stated that El Niño is “knocking on the door” with above-average surface temperatures rising in the tropical Pacific, affirming previous warnings from the World Meteorological Organization (WMO).

Simultaneously, satellite images have shown the emergence of “Kelvin waves” in the Pacific, a potential indication that El Niño conditions are brewing in the ocean.

The El Niño-Southern Oscillation (ENSO) cycle describes how a pattern of climate fluctuations in the Pacific Ocean has a global impact on the world – from wind, temperature, and rainfall patterns to the intensity of hurricane seasons and even the distribution of fish in the seas. 

Every couple of years or so, conditions can flip from El Niño – the "warm phase" of the ENSO – to La Niña –  the “cooling phase” – and vice versa. During El Niño, winds along the equator are weaker. Warm water is pushed back east toward the west coast of the Americas. As a result, less cold water rises toward the surface.

An indication of El Niño? Data from the Sentinel-6 Michael Freilich satellite on April 24 shows relatively higher (shown in red and white) and warmer ocean water at the equator and the west coast of South America.

The global impact of this is profound. The warmer waters cause the Pacific jet stream to move south and extend, causing drier and warmer weather to hit northern parts of the US and Canada, but wetter weather in southern states. 

We’ve been in the midst of continuing La Niña events since September 2020, but 2023 saw tides starting to turn with conditions widely predicted to flip over to El Niño. 

The big fear is that El Niño conditions over the coming years have the potential to raise global average temperatures, which are one of the main gauges used to measure climate change. If this brewing El Niño is a big one, 2023 and 2024 could experience a string of unprecedented heat waves and push global average temperatures into record-breaking territory. 

“Given how warm the oceans are already, a developing El Niño would only increase the chance of record-breaking global ocean temperatures (and global average temperature over both ocean and land), which likely would have important ecological consequences, including for fish and corals,” said NOAA.

Over in Australia, other worrying trends could be afoot. El Niño typically suppresses rainfall in eastern Australia during the winter and spring months, meaning drier weather and a higher risk of wildfires.

It's notoriously tough to predict how the ENSO will pan out, but news of the ongoing trends in the Pacific has got scientists observing the situation with bated breath. 

“We’ll be watching this El Niño like a hawk,” Josh Willis, Sentinel-6 Michael Freilich project scientist at NASA’s Jet Propulsion Laboratory in Southern California, said in a statement.

“If it’s a big one, the globe will see record warming, but here in the Southwest U.S. we could be looking at another wet winter, right on the heels of the soaking we got last winter.”

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A load of 1,800-year-old marble columns has been found among the wreck of a ship in Israel. Dating back to the age of the Roman Empire, this is the oldest sea cargo of its kind ever discovered in the Eastern Mediterranean.

Recent dives to the site have shown that the ship was carrying a number of Corinthian columns measuring up to 6 meters (19 feet) long that are ornately decorated with motifs of plants.  

The ancient shipwreck lies around 200 meters (656 feet) from the coastline of Bet Yannai, around 6 kilometers (3.7 miles) north of the city of Netanya. The site has been known for some time, but the exact location of the cargo was only revealed a few weeks ago when a storm upset the sand in the area.  

While exploring the waters by the beach, the ancient artifacts were stumbled upon by Gideon Harrishe. He notified the Israel Antiquities Authority who sent a team to investigate – and they were far from disappointed.

“We have been aware of the existence of this shipwrecked cargo for a long time, but we didn’t know its exact whereabouts as it was covered over by sand, and we could therefore not investigate it,” Koby Sharvit, director of the underwater archaeology unit at the Israel Antiquities Authority, said in a statement sent to IFLScience. 

The style of the column is typical of Corinthian order.

“The recent storms must have exposed the cargo, and thanks to Gideon’s important report, we have been able to register its location, and carry out preliminary archaeological investigations, which will lead to a more in-depth research project,” he said.

It’s likely the marble came from what is now modern-day Turkey or Greece and was heading for a location along the southern Levantine coast, such as Gaza or possibly even Alexandria in Egypt, where it would be used in the construction of a grand public building.

Unfortunately, it appears the ship succumbed to a storm in shallow waters and the delivery didn’t reach its destination.

“These fine pieces are characteristic of large-scale, majestic public buildings. Even in Roman Caesarea, such architectural elements were made of local stone covered with white plaster to appear like marble. Here we are talking about genuine marble,” Sharvit explains.

Another one of the seafloor Corinthian discoveries.

“From the size of the architectural elements, we can calculate the dimensions of the ship; we are talking about a merchant ship that could bear a cargo of at least 200 tons,” adds Sharvit. 

The unique find helps to answer some questions about Roman-period architecture in the Levant and beyond. 

“Land and sea archaeologists have long argued whether the Roman period imported architectural elements were completely worked in their lands of origin, or whether they were transported in a partially carved form, and were carved and fashioned at their site of destination,” continued Sharvit. 

“The find of this cargo resolves the debated issue, as it is evident that the architectural elements left the quarry site as basic raw material or partially worked artifacts and that they were fashioned and finished on the construction site, either by local artists and artisans or by artists who were brought to the site from other countries, similarly to specialist mosaic artists who traveled from site to site following commissioned projects,” he said.

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Frost quakes, like the ones that struck a city in Finland 26 times in just seven hours, could become more common if the climate crisis continues to cause extreme weather in cold regions. Also known as cryoseisms or ice quakes, these peculiar and understudied weather phenomena are triggered by water freezing in saturated rocks or soil.

The mechanism behind frost quakes means they impact areas where there’s lots of moisture in the earth, often near bodies of water. Then, when there’s a sudden drop in temperature, the water can freeze and expand rapidly, creating stress within the surrounding substrate.

Frost quakes occur when this stress becomes so great that it creates a fracture, shaking the ground. Like an earthquake, frost quakes can be felt and heard, but they don’t reach the same extremes of magnitude. Many frost quakes go unnoticed because they’re so subtle, while others create sounds similar to gunshots and can even cause damage to physical structures like buildings.

However, as YouTube videos demonstrate, they're not always terribly dramatic...

By their very nature, frost quakes are connected to the extremes of weather – something we’re seeing more of as the climate crisis has unfolded in recent decades. As such, researchers were interested to know how climate change may affect Arctic and sub-Arctic regions, including frost quakes. They reported their findings at the European Geosciences Union General Assembly. 

Recent reports from frosty regions like Finland, Canada, and the US have demonstrated the damage these quakes can cause to infrastructure, so it’s a weather phenomenon worth getting to know if we’re going to keep safe during increasingly unpredictable conditions.

To do so, researchers established a model that enabled them to investigate the connection between thermal stress and frost quakes. Thermal stress is related to the stress created by any change in the temperature of a material that causes it to expand and contract, such as the impact of freezing water in saturated soil.

They used a hydrological model to calculate snow depth, snow melt rate, and soil temperature at different depths in the soil and explore what happens when the temperature suddenly changes. This revealed that a rapid decrease in temperature can cause thermal stress strong enough to shatter a soil-ice combo, resulting in the bangs and cracks we’ve observed following frost quakes.

In 2016, Oulu in Finland experienced a rash of frost quakes, as 26 hit the sub-Arctic environment within a seven-hour window. The quakes broke the soil and damaged the foundations of buildings and roads.

Using their models, the researchers of this new paper could calculate that the quakes were triggered by a temperature drop of 17 degrees Celsius (30.6 degrees Fahrenheit) as the cold plummeted from –12 degrees Celsius (53.6 degrees Fahrenheit) to a thermally stressful –29 degrees Celsius (84.2 degrees Fahrenheit) capable of cracking frozen soil and pavement. 

Understanding the tolerance of different substrates may enable researchers to predict areas that could be affected by frost quakes when particularly turbulent weather is expected, perhaps leaving towns and cities better able to prepare.

So, get familiar with “cryoseisms”, kids. It looks like we could be seeing more of these frosty characters in the future.

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Around 300,000 years ago, a family of early humans visited a lake bordered by open forest. We don’t know if they came there to drink, swim, or forage, but hunting the herds of giant beasts found there was probably not on their agenda. Their footprints not only record their presence, but place them in an ecosystem we can reconstruct from other clues.

The prints were found at the Schöningen Paleolithic site in what is now Lower Saxony, which was rescued by archaeological teams in the 1990s from an encroaching coal mine. As a new paper notes, without bones or teeth we cannot identify the species of the footprint makers with certainty. However, Homo heidelbergensis are known to have lived in Europe up to this time, while the presence of no other human species has been established in the area at the appropriate time.

Two of the three tracks at the Schöningen site are from individuals who were not fully grown, suggesting a family group coming to the lake together, and unlikely to be hunting. “Depending on the season, plants, fruits, leaves, shoots, and mushrooms were available around the lake. Our findings confirm that the extinct human species dwelled on lake or river shores with shallow water. This is also known from other Lower and Middle Pleistocene sites with hominin footprints,” said Dr Flavio Altamura of the University of Tübingen in a statement.

Stone tools and horse bones carved with sharpened stone have been found in the same area and dating to around the same time.

A distinctively human footprint, presumed to be H. heidelbergensis.

Other footprints at the site come from Palaeoloxodon antiquus, the straight-tusked elephant that grew to twice the size of a mammoth or African elephant. They are the most northerly Palaeoloxodon footprints ever found, and the first in Germany. We know Palaeoloxodon were hunted by Neanderthals. There is no evidence H. heidelbergensis had the same capacity, but the paper proposes an elephant found nearby had died of natural causes and been scavenged by humans.

“The elephant tracks we discovered at Schöningen reach an impressive length of 55 centimeters [22 inches]. In some cases, we also found wood fragments in the prints that were pushed into the – at that time still soft – soil by the animals,” explained Dr. Jordi Serangeli “There is also one track from a rhinoceros – Stephanorhinus kirchbergensis or Stephanorhinus hemitoechus – which is the first footprint of either of these Pleistocene species ever found in Europe.”

Fossil elephant track in Schöningen 13 II-2 with wood fragments in the footprint backfill. Much of the area was thoroughly trampled by the giant straight-tusked elephant.

Not surprisingly, such immense creatures left deep prints in the soft mud around the lake, and the authors have identified two trampling episodes, interleaved with thin peat deposits. They write, “Animal feet sunk in the peat, reaching or indirectly deforming the muddy substrate.” Much of the area is so trampled individual footprints have been lost, but in some cases tracks clear enough to identify the maker survive.

This may be hard to distinguish from an elephant print to the layperson, but it is really a rhino print of the Stephanorhinus genus.

Among these are three sets of tracks whose toes and curved foot identify them as human. One is of an adult, another a juvenile. The third is more ambiguous, and might not have been recognized as human without its proximity to the other two, but probably comes from another young individual, still some way short of fully grown.

The lakeside forests were a mix of birch, pine and grassy woodlands, providing the mixed ecosystems that suit adaptable humans seeking a mixed diet. 

The paper is published in the journal Quarternary Science Reviews.

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In a world where internet connection is crucial to our lives, having enough bandwidth is very important. And it's important even if you are out of this world. Going beyond radio communications between Earth and Space is work that has been going on for decades and the next big leap will be the return to the Moon. When Artemis II launches next year, it will be using this new approach too.

Optical communication uses infrared lasers instead of radio waves. This massively increases the bandwidth so you can transfer more data in less time, due to the fact that the waves are a lot tighter. It is also less power-consuming. This is the rationale behind using the Orion Artemis II Optical Communications System (O2O) to communicate with the crew on the next big Moon mission.

“The idea is to have high-definition video transmissions to and from the Moon over laser links,” O2O Project Manager Steven Horowitz said in a previous statement. “If you recall the images from the Apollo mission, they were grainy and difficult to see, but O2O will allow Artemis astronauts to send videos and images significantly more vivid and detailed. This is an incredible advancement in technology.”

Obviously, we are excited to see the astronauts talking to us from the orbit of the Moon in high-definition but it is not just for vanity. The approach is crucial for faster data transmission so that procedures, flight plans, and mission-critical communications are sent without delays in the highest quality possible. And there is also the science data, including observations of the Moon, but also regarding the health of the astronauts and the status of the Orion capsule.

Artemis I exceeded expectations when it traveled in deep space last December but actually putting astronauts in there will be a bigger challenge. Fast communication between Earth and the craft is key. Optical communications are expected to become more and more popular, with even the possibility of using them to establish LunaNet, a satellite internet around the Moon. Curiously, the first time an optical satellite was successfully demonstrated was a mission from the European Space Agency also called Artemis back in 2001. 

NASA's Reid Wiseman, Victor Glover, record-breaking Christina Koch, and Canadian astronaut Jeremy Hansen are the four astronauts who will go on a lunar flyby no longer than 21 days. The launch is currently planned for November 2024.

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In previous generations, parents might have reached for the cough syrup to relieve a dry or chesty cough.

But we now know cough syrups aren't very effective at treating children's coughs.

And amid mounting evidence of harms from poisoning and deaths, many countries including Australia have restricted cough medicines so they can't be given to children aged under six.

What's in cough medicine?

Active ingredients in cough syrups vary depending on their claimed benefit. They can contain cough suppressants (dampening the body's cough reflex), expectorants and mucolytics (both of which help clear phlegm).

Other medicines marketed for cold and flu often contain decongestants (to relieve a blocked nose) and sedating antihistamines to relieve sneezing, stop a runny nose and to aid sleep.

The riskiest medications are those with a sedative action, such as sedating antihistamines or opioid-based cough suppressants. While sedation may be a desired effect for parents with a sleepless child, young children are particularly at risk of serious harm or death. Sedatives can also cause agitation and hyperactivity.

While cough syrups that don't contain sedatives are likely safer, there are very few studies of safety and efficacy of these products in children. Adverse events including agitation and psychosis have been reported, especially with overuse.

Overuse may result from parents misreading the label, intentionally using more in the hope it will work better, inadvertent extra doses and the use of inaccurate measuring devices such as household spoons.

How are cough syrups restricted?

Young children under two years old are most at risk of a fatal overdose from cough syrups. But Australia's drug regulator recommends against using cough syrups for anyone under six years of age. As such, there are no dosing instructions for children under six years on the labels of these products.

Cough syrups are still available for older children and adults. Pharmacists are likely to ask the age of the person who will take it and provide guidance on dosing and appropriate use.

Our research, published today in the Medical Journal of Australia, shows restricting the use of cough and cold medicines in children results in a significant and sustained decrease in poisonings.

Our study looked at dosing errors, adverse events at correct doses, and accidental "exploratory ingestions", such as when a toddler helps themselves to the medicine cabinet.

The government mandated labeling changes in 2012 and 2020 for these products. In 2012, labels for medicated cough and cold products could no longer list dosing instructions for children under six, and had to carry additional warnings. In 2020, warnings were put on sedating antihistamines saying they were not to be used in children under two years for any reason (including allergy and hayfever).

This resulted in a halving of the rate of poisons center calls, and a halving in the rate of hospitalizations. Despite this, hundreds of calls are still made to Australian poisons centers per year regarding these products in young children.

When is it OK to use cough syrups?

Harms have mostly been documented in younger children. This is likely due to their smaller size, meaning it takes less medicine to cause harm, and also their susceptibility to sedative effects due to their developing brains.

Cough syrups can be used for in children aged six to 11 years, however caution is still needed. These products should only be given in consultation with a doctor, pharmacist or nurse practitioner.

Some herbal products are available and marketed for children, such as Hedera helix (ivy leaf extract). Unfortunately, there is no convincing evidence these medications meaningfully improve cough symptoms. But the risk of poisoning is low.

Simple syrups containing no medication can also be effective: up to 85% of the effectiveness of cough medicines has been put down to the "placebo effect". This could be due to syrups coating the throat and dampening that irritating tickling sensation.

So what can I do for my kid?

The best thing you can do for your child is give them rest and reassurance.

Antibiotics will only be needed if a doctor diagnoses them with acute bacterial pneumonia or with a chronic cough due to a bacterial infection, such as protracted bacterial bronchitis, whooping cough or a lung abscess.

Paracetamol or ibuprofen can be used if they have fever, aches and pains along with their cough. Check the correct dosage on the packaging for your child's weight and age.

If your child is older than 12 months and has a wet cough (producing phlegm in their throat), consider giving them honey. There is growing evidence honey can reduce the production of mucus and therefore, the amount of coughing.

Journal information: Medical Journal of Australia 

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An NBC News report on YouTube talks about how driverless cars from GM's Cruise and Google's Waymo, which got permission to offer cab services in San Fransico in 2022, are now responsible for three 911 calls a day in the city. The report says the cars can get confused and stop entirely if they encounter construction or red lights from emergency vehicles, leading to traffic jams.

It's a particular problem for the city's fire department and first responders. One fire chief says she sees at least one incident a day with driverless vehicles. Other reports filed by the department include autonomous vehicles driving toward active fire scenes and running over hoses. One report claims firefighters had to break one of these cars' windows in order to stop it. The fire chief interviewed stated she doesn't believe these cars are "ready for prime time."

The local Department of Transportation doesn't have much power over Google or GM to control these vehicles, thanks to special rules made at the state level that doesn't allow the city of San Francisco to regulate driverless vehicles.

NBC was not able to get GM to comment on these issues with its Cruise vehicles. Waymo's chief safety officer Mauricio Pena was interviewed on camera. He claims it has "very infrequent events that occur" but when it is pointed out that the city is now getting three 911 calls a day about driverless cars, he says those "infrequent events" are "relative to the number of miles we drive and relative to the number of emergency contacts that we face on a day-to-day basis."

Pena also says they plan to increase the number of Waymo cars on San Francisco streets by 10 times the current number this summer. That doesn't make Jeffrey Tumlin, the city's transportation director happy. He claims that if Waymo goes through with its plan, "it would have a dramatic impact on congestion. It would result in significant delays in our transit system, and to emergency vehicle response time."

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The light pollution caused by coastal cities can trick coral reefs into spawning outside of the optimum times when they would normally reproduce, a new study has found.

Coral broadcast spawning events – in which lunar cycles trigger the release of eggs on certain nights of the year – are critical to the maintenance and recovery of reefs following mass bleaching and other similar events.

However, using a combination of light pollution data and spawning observations, researchers were able to show for the first time that corals exposed to artificial light at night (ALAN) are spawning one to three days closer to the full moon compared to those on unlit reefs.

Spawning on different nights could reduce the likelihood of coral eggs being fertilized and surviving to produce new adult corals that help reefs to recover after bleaching events and other disturbances.

The research, published today (May 15) in Nature Communications, is the latest to be carried out as part of the Artificial Light Impacts on Coastal Ecosystems (ALICE) project, which is funded by the Natural Environment Research Council.

It builds on research published in December 2021 which mapped out the areas of the ocean most affected by light pollution.

That study found that at a depth of one meter, 1.9 million sq km of coastal ocean are exposed to biologically important ALAN (around 3.1% of the global Exclusive Economic Zones).

For the new study, researchers paired that data with a global dataset of 2,135 coral spawning observations from the 21st century.

This enabled them to demonstrate that ALAN is possibly advancing the triggers for spawning by creating a perceived period of minimum illuminance between sunset and moonrise on nights following the full moon.

Dr. Thomas Davies, Lecturer in Marine Conservation at the University of Plymouth, is the study’s lead author and also principal investigator of the ALICE project. He said: “Corals are critical for the health of the global ocean, but are being increasingly damaged by human activity. This study shows it is not just changes in the ocean that are impacting them, but the continued development of coastal cities as we try and accommodate the growing global population. If we want to mitigate against the harm this is causing, we could perhaps look to delay the switching on of night-time lighting in coastal regions to ensure the natural dark period between sunset and moonrise that triggers spawning remains in tact. That would potentially raise a number of economic and safety issues, but is something we potentially need to consider to ensure our coral reefs are given the best chance of survival.”

Dr. Tim Smyth, Head of Science for Marine Biogeochemistry and Observations at Plymouth Marine Laboratory and the study’s senior author, added: “This study further emphasizes the importance of artificial light pollution as a stressor of coastal and marine ecosystems, with the impacts on various aspects of biodiversity only now being discovered and quantified. A critical first step along that path was enabled with our global in-water light pollution atlas which highlighted for the first time the true extent of the problem, which hitherto had gone unrecognized.”

The study looked at coastal regions all over the world, but coral reefs in the Red Sea and Persian Gulf are particularly affected by light pollution.

They are areas where coastlines have been heavily developed in recent years and where coral reefs are both close to the shore and at particular risk.

Co-author Professor Oren Levy, who heads the Laboratory for Molecular Marine Ecology at Bar-Ilan University in Israel, added: “The Red Sea and the Gulf of Eilat/Aqaba are heavily impacted by Artificial Light at Night (ALAN) due to urbanization and the proximity of the reefs to the coastline. Despite the challenges posed by ALAN, corals in the Gulf of Eilat/Aqaba are known for their thermal tolerance and ability to withstand high temperatures. However, a disturbance in the timing of coral spawning with the moon phases can result in a decline in new coral recruits and a reduction in the coral population. It is crucial that we take immediate action to reduce the impact of ALAN on these fragile marine ecosystems. By implementing measures to limit light pollution, we can protect these vital habitats and safeguard the future of the world’s oceans. It’s our responsibility to ensure that we preserve the biodiversity of our planet and maintain a healthy and sustainable environment for generations to come.”

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Nearly 2 percent of the U.S. population reported cocaine use in 2020, and the highly addictive substance was involved in nearly one in five overdose deaths, according to the Centers for Disease Control and Prevention (CDC). 

In Virginia, the number of cocaine-related overdoses has been increasing since 2013, with 968 fatal overdoses in 2022, a 20 percent increase over 2021, according to preliminary data from the Virginia Department of Health. Of those, four in five included fentanyl — prescription, illicit, or analog — a driving force behind the fatalities.

Researchers at the Fralin Biomedical Research Institute at VTC are working to better understand cocaine use disorder and help reverse the national trend. 

“Stimulants are coming back. Cocaine use and addiction has been rising for more than a decade with no robust treatment,” said Warren Bickel, professor with the Fralin Biomedical Research Institute at VTC and director of the Addiction Recovery Research Center. “We need some new ideas.”

The total number of fatal cocaine-related overdoses in Virginia has been slowly increasing since 2013. Researchers at the Fralin Biomedical Research Institute at VTC are working to better understand cocaine use disorder to help reverse the trend. Credit: Leigh Anne Kelley/Virginia Tech

 

The study stresses the theory of reinforcer pathology, in which an individual places a higher value on immediate reward — for instance, for the way a substance makes them feel — and a lower value on future gains. For the study, researchers will use cocaine contingency management by providing cash or something of value to people who meet their treatment goals.

“When people do drugs, we know they give up their jobs, relationships, family, even their lives, but when they receive several dollars for drug-free urine samples, they become powerful. What explains that? Their temporal horizon. I give you money for a clean urine sample and right away you turn it around. The drugs lose value,” Bickel said.

The Addiction Recovery Research Center is recruiting adults who use cocaine for the paid research study on decision-making. Participants will be asked to visit the Roanoke lab 13 times over five weeks to undergo MRIs, report their cocaine use, take computerized assessments, and provide urine samples. The research, which is not a treatment study, is supported by a grant of more than $700,000 from the National Institute on Drug Abuse, part of the National Institutes of Health.

“We are asking people to participate for several weeks in a row, and we will learn whether tackling their short-term view of the future can be an added key to treating them,” Bickel said. “It is worthwhile to explore new ideas. New interventions are long overdue, and there is increasing evidence that this effort is an idea whose time has arrived. It is producing effects we want to measure.” 

Bickel also is director of the institute’s Center for Health Behaviors Research, a psychology professor with Virginia Tech’s College of Science, and a professor of psychiatry and behavioral medicine at the Virginia Tech Carilion School of Medicine. He is joined on the study by co-investigator Stephen M. LaConte, an associate professor at the Fralin Biomedical Research Institute.

LaConte said he’s privileged to work alongside colleagues tackling substance use disorders. “I am thankful to the participants who donate their time to come to the [institute] for our studies,” said LaConte, who will use brain imaging to study the effects of cocaine use and changes to the brain during the intervention. “Beyond funding the science that we do here, I am also grateful to our state and federal agencies for their work in helping to reduce the stigma surrounding addiction.”

Their goal is to positively impact public health by guiding innovative interventions that help decrease cocaine consumption.

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Antarctic ice sheets contain sixty percent of the planet’s freshwater, amounting to an almost incomprehensible thirty million cubic kilometers of ice. To put this into perspective, if all of this Antarctic ice were to completely melt, it would lead to an average global sea level rise of 58 meters.

“The ice sheet in East Antarctica stores enormous amounts of water. This means that this is the biggest possible source of future sea level rise – up to 53 meters if all of the East Antarctic ice melts – and is seen as the largest source of uncertainties in the future sea level adaptation planning,” says Irina Rogozhina, an associate professor at the Department of Geography at the Norwegian University of Science and Technology (NTNU).

Most melting/ice loss in Antarctica happens through ocean-driven melting of ice shelves and ice calving. This, in turn, leads to an acceleration of ice streams on land and a greater discharge of ice into the ocean, where it gets lost to melting/calving, she said.

This was also likely the cause of larger ice loss during warmer periods of the past. In Greenland, these two processes contribute about 65% of all ice loss. But not all the ice needs to melt before it can have major consequences.

Researchers from NTNU were among a group of scientists who examined the ice in Queen Maud Land in East Antarctica. The results show that this ice sheet sector has varied a lot over time. This information is important as researchers try to learn more about the planet’s climate and how it is changing.

Rogozhina’s group studied the ice sheet in East Antarctica and a meltdown that took place a few thousand years ago. The results have been published in the journal Communications Earth & Environment.

The American researcher Nat Lifton in front of Cottontop Mountain in Heimefrontfjella, East Antarctica. He’s looking for stones that can be collected and analyzed for cosmogenic isotopes. The six-wheeled pickup truck is used to transport researchers from the Antarctic research station where they’re staying to their different field sites. Credit: Carl Lundberg

The ice in the east lies on land

The ice sheet in Antarctica is not evenly distributed or uniform. In the west, large parts of the ice sheet lie under sea level, down to a depth of 2,500 meters. This makes it very vulnerable to ocean warming. In contrast, much of the ice sheet in the east sits directly on land, above sea level, meaning it is less sensitive to the ocean’s influence.

This ice sheet sector in East Antarctica was thinner in the past than it is now, and not particularly long ago either. In fact, it was thinner following the end of the last ice age, when massive ice sheets previously covered North America, northern Europe, and southern South America. When these ice sheets melted, they raised the sea level by more than 100 meters.

“From the evidence we presented in our study, we concluded that the East Antarctic ice sheet in Queen Maud Land also melted rapidly along its margins between 9,000 to 5,000 years ago, in a period we call the mid-Holocene. At this time, many parts of the world experienced warmer-than-present summers,” Rogozhina said.

“Although this kind of response by the East Antarctic ice sheet to the warmth during the Holocene is not completely unexpected, it is still difficult and worrisome to believe that the sluggish East Antarctic ice sheet can change so rapidly,” she said.

It’s difficult to find a simple, easy explanation for this behavior, or to determine the exact timing when the melting took place, not least because the conditions in this part of the world are rather inhospitable at times.

But the researchers found a way to unravel this mystery.

Researcher Nat Lifton (closest) and mountain guide Carl Lundberg (higher up) climb a small nunatak to look for suitable rock samples. Credit: Ola Fredin, NTNU

Cosmic radiation changes rocks

The research group examined rocks from various nunataks in Queen Maud Land for exposure to cosmic radiation.

“Nunataks are mountains that stick up through the ice. We have visited nunataks and taken samples,” says Ola Fredin, a professor at NTNU’s Department of Geosciences and Petroleum.

The researchers examine different isotopes, or variants, of elements such as chlorine, aluminum, beryllium, and neon in rocks from the nunataks. With the help of cosmogenic isotopes, they can figure out how high the ice was over geological time in Queen Maud Land. Fredin compares this to using a dipstick to measure the level of engine oil in your car.

In this way, the researchers can say something about how long the rocks have been exposed to cosmic radiation. They can then also say something about how long it has been since the rocks have been under a protective layer of ice and thus have not absorbed any cosmic radiation.

For this, they use data from different areas and run a variety of computer simulations.

Rising seas and warmer water broke up the ice

The researchers also believe that they are on track to find a reason why the ice sheet sector in East Antarctica thinned so much immediately after the end of the last ice age.

“We believe that the ice sheet became less stable due to higher, regional sea levels and warmer water rising from the ocean depths in the polar regions, penetrating under the ice margins and melting them from below. This leads to the breakup of large icebergs and accelerates the movement of ice from the land to the ocean, which in turn thins the inland section of the ice sheet. The process is similar to when a house on a hill slope loses its supporting foundation and starts sliding downhill,” Rogozhina said.

In short, the less stable, rapidly flowing parts of the ice sheet in East Antarctica, which are called ice shelves and float on the ocean, were broken up more easily, which in turn led to the ice sheet becoming much thinner within a relatively short time, geologically speaking, or a few hundred to thousands of years.

Thick ice is the most common along the coast

Cosmic radiation can also help researchers figure out how common it is for ice to cover an area. The researchers have also investigated this.

The results show that it is most common for the ice in Queen Maud Land to be thick along the coast. But not further into the continent, where mountain peaks protrude through the ice and the land can be several thousand meters high.

“We found that the land masses along the coast of Queen Maud Land have been covered by ice between 75 and 97 percent of the time during the last one million years,” Fredin said.

He was part of another study, which has also had its results published in the journal Communications Earth & Environment. This group examined rocks from several different areas in Queen Maud Land and found great variations.

“In contrast to areas along the coast, which have been ice-covered most of the time, we find that mountain summits further into the continent have been ice-covered as little as 20 percent of the time,” Fredin said.

The ice sheet thickness and movement speed, therefore, vary a great deal over longer periods, and the mountain range further into the continent seems to be an important division between the dynamic coast and the ice sheet further toward the South Pole, which varies much less in thickness.

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