That's why the dwarf reed snake (Pseudorabdion longiceps) developed what appears to be a unique way of fleeing. When danger approaches, the small, South Asian serpent flings itself ass over teakettle in a bizarre cartwheeling motion that expedites its escape.

A new paper represents the first time this behavior, rarely seen in any animals, has been documented in snakes.

"We report in detail an observation of a novel escape behavior employed by this species – cartwheeling," write a team of researchers led by biologist Evan Seng Huat Quah of Universiti Malaysia Sabah.

"Previously, there have only been anecdotal reports of this behavior and this is the first time it is documented with images and a detailed description."

For an animal that is basically a scaly wigglestick with a sometimes-venomous bite, snakes do have a number of strategies for evading predation by other, bigger animals. These include camouflage, playing dead, fleeing, aggression, and defensive posturing. But smaller snakes are especially vulnerable to predation.

The dwarf reed snake is a secretive, nocturnal animal that hides itself in leaf litter or under logs during the day. Growing to a teensy 23 centimeters (9 inches) in length, its a perfect snack for predators that are known to include birds and other snakes, so it has a lot to contend with as it goes about its slithery business.

Crossing a mountain road in Malaysia one evening in August 2019, researchers happened across one such specimen. As they drew near, the startled snake flipped – literally – performing a series of cartwheels as it careened away.

"When approached, the snake was startled and throwing the coils of its body into a loop and began rolling to try and escape. The snake cartwheeled approximately 1.5 meters (5 feet) in less than 5 seconds down the road. By cartwheeling down an incline, the snake was able to gain speed and rapidly cover more ground," the researchers describe.

It was the humans' turn to be startled, but they didn't remain so for long: they caught the snake, and placed it on a flat piece of ground, where they observed the snake repeat the behavior several times, showing that the wildly flailing escape method wasn't simply the result of a scare and gravity. And they documented it, capturing it in a series of images that allowed them to analyze exactly how the snake does what it does.

Series of images showing how the snake throws its coils forward in a cartwheeling motion. (Evan Quah)

The motion begins with the snake pulling its body into an S-shape, then launches the front half of its body into the air by pushing its tail against the ground. The entire body of the snake becomes airborne; when the head touches the ground, the tail flips forward, while the head and neck coil to launch again. The entire maneuver repeats; basically, the snake throws the coils of its body forward over each other repeatedly.

You can observe this behavior in action in the video below, captured by campers; the cartwheeling escape starts at around 1:50.

It's not quite the fearsome Hoop Snake of legend… but it would still be pretty alarming if you weren't expecting it.

Although other animals – including the golden wheel spider (Carparachne aureoflava) and some salamanders – roll to escape predators, their action is typically passive. The animal simply makes itself small and rolly, and the environment and gravity do the rest.

The dwarf reed snake stands out in its talent for active rolling, in which the reptile expends energy to flip away.

The odd behavior, the researchers said, could have a number of benefits. Combined with passive rolling (that is, when fleeing down a hill), the motion could help the snake move more quickly. The sudden flurry of motion could also serve to distract and confuse predators, while the snake makes its stylish exeunt. And the reduced contact the snake's body has with the ground could result in a patchy scent trail, which would confuse nocturnal predators that rely more heavily on smell than sight.

Snakes can be pretty enigmatic creatures, so it's not unprecedented that they have ways of getting around that haven't been documented. It wasn't too long ago that scientists recorded snakes using a peculiar "lasso" method to climb trees. So it's likely that this species isn't the only snake to cartwheel away from danger.

"My colleagues and I were excited when we successfully captured images that documented cartwheeling behavior in this species," Quah says.

"We believe that this behavior may be more widespread in other small snake species, especially members of the subfamily Calamariinae, but the lack of records is probably an artifact of the challenges in detecting and observing these secretive species."

The research has been published in Biotropica.

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Locks of hair that may have belonged to Bronze Age shamans in Menorca, Spain, have been found to contain traces of psychoactive alkaloids. Hidden in a secret compartment at the back of a burial cave, the hair samples provide the first direct evidence of hallucinogenic drug use in ancient Europe.

Dated to around 3,000 years ago, the hair strands tested positive for the alkaloids scopolamine and atropine – both of which are known to cause hellish deliriums – as well as the stimulant ephedrine.

The peculiar discovery was made in the Es Càrritx cave, which sits on the Balearic island. Speaking to IFLScience, study author Elisa Guerra-Doce explained that “the cave was in use from 1600 BCE and became a funerary site slightly later – around 1400 BCE. Part of the cave continued to be used as a place for burials until around 800 BCE.”

Previous excavations have revealed that at least 210 individuals were interred in the cave during this 600-year period and that some of the deceased had their hair dyed red. A few strands of colored hair were then sometimes placed in small tubes crafted from wood or antler and placed next to their dead owner’s corpse.

However, in a new study, Guerra-Doce and her colleagues document the discovery of “a small space deep in the cave that had remained sealed since [about 800 BCE].” Dug out of the rock and concealed beneath a layer of clay, the hidden nook contained a stash of ten tubes with dyed hair inside, as well as other wooden, ceramic, and bronze items.

Artist's impression of the hair-dying ritual at Es Càrritx. Image credit: Oriol Garcia i Quera, ASOME-Universitat Autònoma de Barcelona

Using ultra-high-performance liquid chromatography and high-resolution mass spectroscopy, the researchers detected the presence of scopolamine, atropine, and ephedrine in these hidden hair samples. “The interesting thing about this work is that it documents the consumption [of hallucinogenic plants] in human samples for the first time,” explained Guerra-Doce.

“Previously, plants with psychoactive properties had been documented in numerous archaeological contexts – including some that are much older than Es Càrritx – but these were all indirect evidence,” she says. Indeed, excavations across Europe have found opium poppy residues and other plant material on ancient pots or other containers. 

“The presence of these plants at these sites doesn’t necessarily mean that they were exploited as drugs,” continues Guerra-Doce. “But our study shows that these people actually consumed these drugs, which were derived from various plants.”

Scopolamine and atropine, for instance, occur in plants belonging to the infamous datura group, as well as certain other types of nightshade. According to the researchers, these alkaloids have the capacity to generate “extreme mental confusion, strong and realistic hallucinations, disorientation… [and] out-of-body experiences and a feeling of alteration of the skin, as if growing fur or feathers.”

“Considering the potential toxicity of the alkaloids found in the hair, their handling, use, and applications represented highly specialized knowledge,” continue the study authors. “This knowledge was typically possessed by shamans.”

Based on this assumption, Guera-Doce says it’s likely that the hair in the hidden containers belonged to Bronze Age shamans. “The use of these substances may have been restricted to those with special knowledge of how to manipulate them,” she says.

Intriguingly, the tubes containing the hair samples were decorated with concentric circles, which may represent eyes and therefore allude to the “inner vision” obtained by shamans who ingested hallucinogenic plants.

Addressing the mystery of why these artifacts were deliberately hidden, Guerra-Doce says there is some evidence that the population of Menorca experienced “social instability” around 3,000 years ago. “In this context, in the cave of Es Càrritx, some individuals reluctant to abandon ancient traditions, concealed a collection of ritual objects belonging to certain members of the community, possibly shamans, in the hope that the former social order could be re-established in the future,” write the researchers.

“And the best location to assure the protection of the assemblage was found going deeper inside the burial ground of the ancestors.”

The study is published in the journal Scientific Reports.

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The permafrost of east Eurasian mountains is slowly melting away, helping to reveal the buried bodies of the much-feared Mongol Empire – as well as their unquenchable thirst for yak milk. 

New research has studied the remains of a cemetery at the so-called Khorig site, located high in the Khovsgol mountains. Dating suggests that the cemetery was operating in the 13th century starting around the time of the Mongol Empire’s unification in 1206 CE. 

This was the year when the infamous Genghis Khan was proclaimed the ruler of all Mongols. With the help of a fearless horseback army, he launched a series of bloody military campaigns across Asia, laying the foundations for the largest contiguous land empire in history that spanned from the Pacific coast of Asia to Eastern Europe. The world was never the same again. 

In 2018 and 2019, the skeletons of 11 individuals were discovered at the elite burial site after they had partially been revealed by melting permafrost. The bodies were still in surprisingly good condition, despite being over 800 years old, thanks to the sub-zero temperatures preserving the remains.

Buried alongside lavish grave goods and dressed in fine materials, it appears the people interred here held a high social status. 

Researchers discovered a gold ornament in the form of a lotus encircling a seated Buddha from the Khorig cemeteries. Image credit: J. Bayarsaikhan

For this latest study, the researchers were particularly interested in analyzing the remains to understand the lifestyle and diets of these Mongol Empire aristocrats. By looking at the proteins found within ancient dental calculus, the team found direct evidence they drank the milk of horses, sheep, goats, cows, and – most notably – yaks.

The team was particularly excited to find evidence of yaks as the animals play a hugely significant role in the culture of people in the high-altitude regions of eastern Eurasia. They’re also extremely practical for life in this harsh environment, providing a high-calorie food source, thick hair for warm textiles, and fat to make useful commodities like candles.

"Our most important finding was an elite woman buried with a birchbark hat called a bogtog and silk robes depicting a golden five-clawed dragon. Our proteomic analyses concluded that she drank yak milk during her lifetime," Alicia Ventresca-Miller, assistant professor of anthropology at the University of Michigan, said in a statement. "This helped us verify the long-term use of this iconic animal in the region and its ties to elite rulers." 

Yaks still play an important part in Mongolian culture today. Image credit: Alicia Ventresca-Miller

"Ceramic vessels were turned into lanterns made of dairy products, which revealed long-standing religious ideas and the daily life of the elites of the Mongol empire," added J. Bayarsaikhan, a researcher at the Max Planck Institute for the Science of Human History and the National Museum of Mongolia.

Although the thawing permafrost has helped scientists find the bodies, it’s leaving the historical remains more vulnerable to looting. If temperatures continue to rise and the permafrost further degrades, then it's feared some frozen archaeological remains, both here and beyond, may be destroyed before they can be properly appreciated. 

"The degree of looting that we are seeing is unprecedented. Nearly every burial that we can locate on the surface has recently been destroyed by looting activity," explained Julia Clark, an archaeologist at Nomad Science.

The study is published in the journal Communications Biology.

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Different processes in the brain happen on different timescales: While sensory input can be handled within tens of milliseconds, decision making or other complex cognitive processes may require integrating information over up to several minutes. Correspondingly, some areas in the brain are faster-paced than others.

These intrinsic timescales are not rigid and invariable. However, so far little was known about how they can adapt to different situations and tasks. A team of researchers from Tübingen, Princeton, Stanford, Newcastle, and Washington has now investigated how the timescale of a brain area can vary during task execution. Specifically, they asked: when a subject focuses their visual attention or redirects it to a specific point in space, how does that change the timescale of neural activity in the corresponding brain area? To answer this, the researchers analyzed previously published data recorded from the visual cortex V4—the brain area involved in visual attention—of macaque monkeys during two different visual attention tasks.

For both tasks, the team observed that the neural activity unfolded not on a single timescale, but on at least two different ones: a slow and a fast timescale. Remarkably, the slow-paced timescale also changed during task execution: whenever the attention was directed to an area in the visual field, the slow activity in the corresponding neural populations became even slower. Moreover, they observed that the slower the activity, the shorter the reaction times.

"This may seem counterintuitive, but it is actually quite plausible," comments Roxana Zeraati, researcher at the University of Tübingen and at the Max Planck Institute for Biological Cybernetics. "A slow timescale means that there is a stronger correlation between the present state of the brain and its state a moment ago. When the neurons are attending to something, they remember their own past activity better, and this implies a slower timescale."

Rich network structure enables flexible behavior

The researchers wondered how a network of neurons can create these different timescales. "We tested three different hypotheses with computer simulations," says Anna Levina, assistant professor in Tübingen and Zeraati's Ph.D. advisor. "Do we see the different timescales simply because some neurons operate faster and others slower? Or, as a second option, could their different biophysical properties be responsible? Only our third conjecture proved true: the answer does not lie in the properties of single neurons, but in the structure of the network."

Depending on how the neurons are connected to each other, different timescales arise: so-called clustered networks, for example, generate slow timescales. "You can compare a clustered network to the European road system," explains Levina, who led the project together with her colleague Tatiana Engel from Princeton. "Any two places in Paris are very well connected to each other, but it is a lot harder to get from a village in Burgundy to a beach in Portugal. At the same time, the airline network might look almost random. It is very hard to reach a nearby city, but you can go almost anywhere without many connecting flights. Networks that look more like airlines would not evolve as long timescales as the road network."

The team was able to construct networks that replicated in the computer simulation exactly the timescales from the experimental data. The models also account for the observed modulations in timescales during tasks: the efficacy of interactions between neurons increases slightly, and this in turn changes the pace of neural events.

The findings could change our outlook on the brain: "Our experimental observations combined with the computational model provide a basis for studying the link between the network structure, functional brain dynamics, and flexible behavior," the publication concludes.

Provided by Max Planck Society

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Migraine is a neurologic disorder that not only causes headaches, but often also a constellation of symptoms that can impact daily living, explains Jason Sico, MD, MHS, a Yale Medicine neurologist.

"We know migraines are caused by changes in the body and the brain chemistry and that genetics account for about half of all migraines," Dr. Sico says. "Often, it is associated with nausea and vomiting, as well as sensitivity to light, sound, and smell."

Furthermore, a migraine headache is often preceded and followed by a few days of feeling "off," which can include fatigue and low mood.

Unfortunately, some patients don't speak up about migraine because they've been dismissed by a medical professional in the past, Dr. Sico adds.

"This is something that profoundly affects someone and their family, and if people are taking over-the-counter medication to treat their pain multiple times a day or even daily, that tells me something is going on that we need to investigate further," Dr. Sico says. "And paradoxically, over time, if people are taking pain medication as needed, that can actually make the headache worse, and sometimes they develop a new type of headache."

The good news is that many migraine treatments, including new medications, have come out in the past decade. Plus, there is strong evidence that certain vitamins and supplements can prevent—or at least reduce the severity of—migraines, Dr. Sico says.

Neuromodulation devices, which use small electrical or magnetic impulses to stimulate parts of the brain, can also prevent migraines or mitigate their effects.

The bottom line, Dr. Sico says, is to speak up if you are experiencing headache pain. "It's not just in your head. And if you bring it up to a doctor who is dismissive, find someone else to talk to about it, because there are people who want to understand your pain and help treat it," he adds.

Provided by Yale University

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Approximately 23 million Americans take levothyroxine, making it one of the most prescribed drugs in the country. To test for hypothyroidism (underactive thyroid), clinicians measure the levels of thyroid-stimulating hormone (TSH) and free thyroxine (Free T4).

However, new research points to natural seasonal variation in these hormones that current laboratory testing does not take into account. This is leading to an enormous number of unnecessary levothyroxine prescriptions, and its overuse presents risks to patients, warns Joe El-Khoury, Ph.D., associate professor of laboratory medicine, in a letter published in Clinical Chemistry on March 1.

"The emerging evidence is very concerning because we're actively giving patients a drug that they don't need that can have potentially severe side effects, especially in elderly individuals over 80," says El-Khoury.

How hypothyroidism is diagnosed

Patients suffering with hypothyroidism may experience symptoms including fatigue and depression, and in extreme cases, the condition can be debilitating. Providers diagnose hypothyroidism by first measuring TSH levels in the blood. If the level is elevated, they will conduct a second test examining Free T4 levels. If TSH is high and Free T4 is low, the provider diagnoses the patient with hypothyroidism. Levothyroxine works by supplementing the low hormone levels with exogenous T4.

Some patients, however, have mildly elevated TSH and normal Free T4. Providers diagnose this as subclinical hypothyroidism, and sometimes this is also treated with levothyroxine to lower TSH. This practice may do more harm than good. "Study after study has shown that there is greater risk when you overtreat with levothyroxine in patients who may not need it," says El-Khoury.

A 2021 study including collaborators from Yale School of Public Health, Mayo Clinic, and University of Arkansas found that out of the 23 million Americans who are actively taking levothyroxine, approximately 21 million [~90%] likely don't need the prescription. Because levothyroxine can cause side effects including anxiety, heat intolerance, and diarrhea—and in extreme cases, cardiovascular morbidity and death, especially in those over 80—this finding is alarming, says El-Khoury.

Diagnosing hypothyroidism may depend on the season

According to El-Khoury, a major reason for inappropriate diagnoses is seasonal variation. Typically, TSH is higher in the winter. This is also when more people may experience symptoms of seasonal affective disorder (SAD), which can have symptoms similar to hypothyroidism. Because current screening measures do not consider the natural variation, many patients presenting with hypothyroidism-like symptoms are getting tested at a time when their TSH levels are naturally higher and being prescribed levothyroxine. "But if many of those same people had gotten the same test a few months later, it would have come back as normal," says El-Khoury.

El-Khoury hopes to raise awareness about the extent of this problem and encourage providers to re-test their patients at least 3 months later before initiating levothyroxine treatment. Furthermore, he believes that the American Thyroid Association and such laboratory organizations as the American Association for Clinical Chemistry's AACC Academy need to carefully consider and agree on a clinical decision limit for TSH.

The assay used at Yale defines the normal limit for TSH as between 0.27 and 4.2 mIU/L. However, recent research suggests that levothyroxine has no benefit in patients who initiate treatment when their levels are naturally under 7.0 mIU/L. "This evidence needs to be reviewed and agreed upon by these medical associations so that we can make changes nationally and perhaps even internationally," he says.

To many, raising the limit from 4.0 mIU/L to 7.0 mIU/L may seem like a big change. However, the emerging findings highlight that the currently accepted range is no longer backed by evidence and the need exists to reevaluate the existing literature. "TSH has such high biological variability that we have not taken into account for so many years," says El-Khoury. "We need to reexamine what we thought to be normal."

For patients currently taking levothyroxine, El-Khoury urges them not to stop taking levothyroxine without consulting a medical professional. "Ask your doctor if levothyroxine is really right for you, if your TSH value was less than 7 mIU/L when treatment was initiated," he says.

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How Pink Floyd inspired research into medieval monks and volcanology

With a starting price of $26,500, it's no surprise that Chevrolet has sold a lot of Bolt EVs this year.

General Motors

 

As we're now in the second quarter of the year, automakers have been reporting their sales numbers. Tesla, which we covered on Monday, is far and away the leader when it comes to electric vehicle sales in the US. But as more and more automakers are bringing new EVs to market, Tesla's market share is eroding, from 72 percent at the beginning of last year to 54 percent now—and it may fall to less than 50 percent over the next few weeks. Which of those other automakers are managing to move metal? We took a look through the Q1 sales announcements to get an idea.

 

While most automakers have published their Q1 2023 sales, this is not a universal list. In particular, Porsche, Mercedes-Benz, Lucid, and Genesis have yet to reveal those numbers as of April 5. And the manufacturers don't all break out data in the same way, either lumping all EVs together (looking at you, General Motors) or grouping different powertrains together (as is the case with the Kia Niro and Hyundai Kona).

 

It's also helpful to remember that, other than Tesla, Rivian, and Lucid, all the other automakers have product lines other than battery EVs, so such a company probably isn't going out of business next week because it only sold 3,000 EVs in three months. Supply chains still aren't back to what was considered normal pre-pandemic, and it's worth remembering that in most cases, these are global products. There are severe penalties for automakers who don't sell enough EVs in Europe and China, unlike here in the US. So in cases of finite supply, those markets will receive priority when it comes to deliveries—every EV you sell in the US is an EV you can't sell in Germany, after all.

General Motors is best of the rest

General Motors had a good Q1 this year, selling "more than 20,000 EVs," according to a press release that does not provide any more granularity to that figure. But a little digging reveals that the vast majority of these were Bolt EV and Bolt EUV sales, with 19,700 vehicles finding homes in the first three months of 2023. That's up from 358 for Q1 2022, when the cars were taken off the market for some time due to a battery manufacturing defect.

 

Cadillac has delivered almost a thousand Lyriq SUVs so far this year, but the same cannot be said for the GMC Hummer EV. That's due to a production issue that shut down production of the Hummer from last October until the end of January. The BrightDrop Zevo 600 delivery van was also affected by that recall/stop sale, but BrightDrop says it has started shipping the first 500+ vans it built this year.

 

Next up is Ford, which sold 10,866 battery EVs in Q1, an increase of 41 percent year on year. Just under half of those sales were of the F-150 Lightning pickup truck—Ford says it's on track to reach a production rate of 150,000 Lightnings a year in 2023. The company hasn't given us a breakout of Mustang Mach-E and E-Transit sales, but it reported that E-Transit sales were up 62.7 percent and that Mach-E sales were down, "reflecting downtime at the plant for changes to increase production."

 

Other than Tesla, which car companies are selling lots of EVs?

A New Zealand-based space company, Dawn Aerospace, said Wednesday it had completed the first three test flights of a rocket-powered spaceplane.

This Mk-II Aurora vehicle measures 4.5 meters long and is powered by a combustion rocket engine fueled by kerosene and hydrogen peroxide. During its initial flights, the vehicle flew to an altitude of about 1,800 meters and reached a maximum speed of about 315 kilometers per hour, the company said.

The test campaign, which is taking place from the Glentanner Aerodrome in New Zealand, will eventually see this vehicle top out at about 20 kilometers. The lessons learned from this plane will be put into a second version of the Mk-II Aurora, which could take flight before the end of this year or early in 2024.

Exploring the upper atmosphere

In an interview, Dawn Aerospace chief executive Stefan Powell said this second vehicle would have a far lighter structure, a more powerful engine, and other features that would allow it to climb far higher. The goal is to fly the spaceplane to an altitude of 100 km, above the internationally recognized boundary of space.

"It's only going to be capable of carrying a few kilograms of payload," he said. "So you're not really launching anything. There's no second stage you can carry with five kilograms. But I do think that what's really unexplored is the suborbital market in this category."

What Powell means is that there is currently no capability to do regular, repeatable research in the atmosphere from about 30 km up to 100 km. With the Mk-II Aurora, the company seeks to be able to fly the vehicle twice a day, offering a platform for applications such as environmental research in the mesosphere and thermosphere.

"Above 30 km is too high for balloons and too low for satellites," he said. "Some researchers refer to it as the ignore-o-sphere. We know it has large implications on climate models and weather models. So there is theorized to be a lot of value in understanding this part of the atmosphere better. So we'll probably just start sticking some pretty basic data gathering payloads onboard just because they don't weigh very much."

The company's goal is to operate its fleet with aircraft-like efficiency—taking off and landing from a runway, using non-exotic fuels, and not requiring significant refurbishment between flights. Vertical launch companies, Powell said, start by building a rocket with a maximum amount of lift capability and work into reusability over time. Dawn seeks to start with a reusable vehicle and build up its capability.

To that end, the Mk-II Aurora vehicle is also a test bed for the larger Mk-III Aurora spaceplane, which aims to deliver an expendable second stage and payload to space. The goal is to eventually be able to launch satellites with a mass of about 250 kg into low-Earth orbit.

Rapid reusability

The Mk-II Aurora takes off under the power of its single rocket engine, which is intended to fire up to an altitude of about 30 or 40 km, after which the vehicle will coast up to about 100 km before reentering Earth's atmosphere. The company is still assessing its options for protecting the spaceplane during the heating of atmospheric reentry, but Powell said his engineering team believes they will be able to use high-temperature composite materials, which is consistent with the company's aim of flying often.

"We're certifying this as an aircraft," Powell said. "So once we get our certification, we're allowed to fly as frequently as we want, provided we stay within the parameters of that certification. You know, we don't go to the regulator every time we want to fly. So that's one massive difference that facilitates rapid reusability."

At present, Dawn Aerospace has about 110 employees, with the majority in New Zealand, but also a technical team in the Netherlands. Half of those work on the company's satellite propulsion business, which is profitable, Powell said. The other half work on the spaceplane. To date, the company has announced fundraising of $20 million. Cash flow from the space propulsion side of the business is helping to fund the Aurora vehicles.

"We are burning cash right now," Powell said. "But it's because we're looking to invest quite heavily into the spaceplane side of things. It's actually quite easy to sort of turn that knob down a little bit and just lean on the space propulsion side. So it's really like it's an elective investment."

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A study led by a UCLA Health researcher found that pregnant women exposed to higher levels of lithium in their tap water had a moderately increased risk of their offspring being diagnosed with autism spectrum disorder. This is the first study to identify naturally occurring lithium in drinking water as a possible environmental risk factor for autism. As lithium levels increased, so did the risk of an autism diagnosis, with the highest quartile showing a 46% higher risk compared to the lowest quartile. The researchers controlled for various factors, including maternal characteristics, socioeconomic factors, and air pollution exposures. The findings are based on high-quality Danish data and need replication in other populations worldwide.

Pregnant women whose household tap water had higher levels of lithium had a moderately higher risk of their offspring being diagnosed with autism spectrum disorder, according to a new study led by a University of California, Los Angeles (UCLA) Health researcher.

The study, published on April 3 in JAMA Pediatrics, is believed to be the first to identify naturally occurring lithium in drinking water as a possible environmental risk factor for autism.

“Any drinking water contaminants that may affect the developing human brain deserve intense scrutiny,” said lead study author Beate Ritz, MD, PhD, professor of neurology in the David Geffen School of Medicine at UCLA and professor of epidemiology and environmental health at the UCLA Fielding School of Public Health. “In the future, anthropogenic sources of lithium in water may become more widespread because of lithium battery use and disposal in landfills with the potential for groundwater contamination.

The results of our study are based on high-quality Danish data but need to be replicated in other populations and areas of the world.”

Because of lithium’s mood-stabilizing effects, some lithium compounds have long been used as a treatment for depression and bipolar disorders. However, there has been debate about whether mothers can safely take lithium during pregnancy amid increasing evidence it is associated with higher risk of miscarriage and cardiac anomalies or defects in newborns.

Ritz, whose research focuses on how environmental exposures influence neurodevelopmental disorders and neurodegenerative diseases, said she decided to examine the possible association between lithium and autism risk after finding there had been little research in humans about how lithium affects brain growth and development. Still, she found that some experimental research indicated lithium, which is among several naturally occurring metals often found in water, could affect an important molecular pathway involved in neurodevelopment and autism.

Zeyan Liew, PhD, MPH, first author of the study and an Assistant Professor of Epidemiology at the Yale University School of Public Health, added that this study was important because prior research findings from Denmark using high-quality medical registry data have already shown that ingestion of chronic and low-dose lithium from drinking can influence the occurrence of adult onset neuropsychiatric disorders. However, no study has been performed to assess whether lithium from drinking water consumed by pregnant women affects their child’s neurodevelopment.

Ritz and Liew worked with Danish researchers who analyzed lithium levels in 151 public waterworks in Denmark, representing the water supply for about half of the country’s population. To identify which waterworks supplied mothers’ homes at the time of their pregnancy, the researchers used address information from Denmark’s comprehensive civil registry system. Using a nationwide database of patients with psychiatric disorders, the researchers identified children who were born in 1997-2013, and compared 12,799 diagnosed with autism against 63,681 children who did not have an autism diagnosis. The researchers also controlled for maternal characteristics, some socioeconomic factors and air pollution exposures, all of which have been linked to increased risk of autism in children.

As lithium levels increased, so did the risk of an autism diagnosis, the researchers reported. Compared to the lowest quartile of recorded lithium levels – in other words, those in the 25th percentile – lithium levels in the second and third quartiles were associated with a 24-26% higher risk of autism. In the highest quartile, the risk was 46% higher compared to the lowest quartile.

The researchers found a similar relationship between increased lithium levels and higher risk of autism diagnosis when the data were broken down by subtypes of the disorder. They also found the association between lithium levels and autism risk was slightly stronger for those living in urban areas compared to smaller towns and rural areas.

In addition to Denmark’s comprehensive civil databases that have proven to be valuable resources for public health researchers, several other factors made Denmark ideal for this study. Denmark’s consumption of bottled water ranks among the lowest in Europe, meaning Danes largely rely on tap water. The country also has a robust system for measuring trace metals and other contaminants in their water supply. Ritz said lithium levels in Denmark’s water, when compared to other countries, are likely in the low to moderate range.

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However, the exact mechanisms behind this process remain unclear in many aspects. Now, a research team at the University of Cologne’s CECAD Cluster of Excellence in Aging Research has recently uncovered one of these mechanisms. Their findings were recently published in the journal Nature Aging.

Professor Dr. David Vilchez and his working group used a non-vertebrate model organism, the nematode Caenorhabditis elegans, and cultivated human cells. Both carried the genes for two neurodegenerative diseases which typically occur in old age: amyotrophic lateral sclerosis (ALS) and Huntington’s disease. Both diseases are characterized by accumulations of harmful and damaging protein deposits – so-called pathological protein aggregations. In both model organisms, cold actively removed the protein clumps, thus preventing the protein aggregation that is pathological in both ALS and Huntington’s disease.

Cold temperatures activate a cellular cleansing mechanism that breaks down defective protein aggregations: Expression of PSME3 in germline, neurons, and gut of nematode. Credit: David Vilchez and Hyun Ju Lee

 

More precisely, the scientists explored the impact of cold on the activity of proteasomes, a cellular mechanism that removes damaged proteins from cells. The research revealed that the proteasome activator PA28γ/PSME3 mitigated the deficits caused by aging in both the nematode and in the human cells. In both cases, it was possible to activate proteasome activity through a moderate decrease in temperature.

“Taken together, these results show how over the course of evolution, cold has preserved its influence on proteasome regulation – with therapeutic implications for aging and aging-associated diseases,” said Professor Vilchez.

Aging is a major risk factor for several neurodegenerative diseases associated with protein aggregation, including Alzheimer’s, Parkinson’s, Huntington’s, and ALS. Vilchez added: “We believe that these results may be applied to other age-related neurodegenerative diseases as well as to other animal species.” A key finding was that the proteasome activity can also be increased by genetic overexpression of the activator.

That way, disease-causing proteins can be eliminated even at the normal body temperature of 37 degrees Celsius. These results may provide therapeutic targets for aging and aging-associated diseases.

It has long been known that while extremely low temperatures can be harmful to organisms, a moderate reduction in body temperature can have very positive effects. For example, a lower body temperature prolongs the longevity of cold-blooded animals like worms, flies, or fish, whose body temperature fluctuates with the temperature of the environment. However, the same phenomenon also applies to mammals, who maintain their body temperature within a narrow range no matter how cold or warm their environment is.

For example, the nematode lives much longer if it is moved from the standard temperature of 20 degrees Celsius to a colder temperature of 15 degrees Celsius. And in mice, a slight decrease in body temperature of just 0.5 degrees significantly extends their lifespan. This supports the assumption that temperature reduction plays a central role in longevity in the animal kingdom and is a well-conserved evolutionary mechanism.

Even in humans, a correlation between body temperature and lifespan has been reported. Normal human body temperature is between 36.5 and 37 degrees Celsius. While an acute drop in body temperature below 35 degrees leads to hypothermia, human body temperature fluctuates slightly during the day and even reaches a cool 36 degrees during sleep. Interestingly, a previous study reported that human body temperature has steadily declined by 0.03 degrees Celsius per decade since the Industrial Revolution, suggesting a possible link to the progressive increase in human life expectancy over the last 160 years.

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Starship is even bigger than NASA's SLS so if it launches it will be the biggest rocket in history to leave Earth. Image credit: SpaceX CC BY-NC 2.0

SpaceX’s Starship might finally take to the sky. The launch vehicle is the tallest and most powerful rocket ever built, even bigger than NASA’s massive Space Launch System that took Artemis I to the Moon. It's also the first to be designed for complete reuse. All going well, its inaugural flight will take place next week.

Back in mid-March, CEO Elon Musk suggested a tentative date of the third week of April for the first test launch of Starship as SpaceX was still waiting for license approval to launch from the US Federal Aviation Administration (FAA).

However, Starship was recently seen on its launchpad and it seems that most of the FAA evaluation is completed, although some environmental issues are still yet to be concluded. If sorted soon, the launch could happen next Monday, April 10, or the day after, as first reported by Ars Technica's Eric Berger, who notes that it appears NASA has reserved the use of its high-altitude WB-57 aircraft to track the rocket's progress. NASA has a big interest in Starship. 

If all goes well, it's likely Starship will be the rocket that will take astronauts in the Artemis program from lunar orbit down to the surface of the Moon and back. It has the capability to be fueled in orbit before moving from low-Earth orbit to the Moon, and maybe one day even Mars. It can move crew and cargo into orbit. 

Potentially, Starship could also be used to do point-to-point suborbital Earth transportation. Those are flights from two different places on the planet. For example, the longest continuous flight, from Singapore to New York, takes almost 19 hours. Starship might be able to do it in about one hour. 

SpaceX also envisions the vehicle as a way to bring more Starlink satellites to orbit, expanding this megaconstellation even more. Starlink is at the center of many controversies as the number of satellites is affecting professional astronomy and they contribute to the pollution of the natural night sky. Musk plans to have at least 12,000 Starlink satellites in orbit, likely outnumbering non-Starlink satellites five to one. 

Official word on the launch of Starship will probably come in the next few days, but it seems almost certain that it will happen this month. 

[H/T: Ars Technica]

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Neil Armstrong walking on the Moon. Faking this would have been far harder than doing it for real. Image Credit: NASA

In response to IFLScience’s recent article about the announcement of the Artemis II crew, author Dr Alfredo Carpineti received an email claiming: “Before we can go BACK to the moon we would have had to have gone there before. WE DID NOT.” Plenty of comments under the article on social media carried similar messages, although it's hard to tell the genuine disbelievers from those engaging in irony or trolling. If even a tiny fraction of these comments are from people who genuinely believe the landings were faked, it’s time to outline the mountain of evidence that Kennedy’s promise was fulfilled.

The idea the landings were faked goes back almost as far as the actual events, but it has taken off in recent years. Perhaps that’s partially because the generation awed by watching the “one small step” in real-time is now a minority, but the main reason is a declining trust in authority. Having been lied to about everything from Watergate to Weapons of Mass destruction, many people are no longer inclined to simply take the word of a US Government agency.

However, instead of applying some skeptical rigor to the question, some have responded by believing everything a random individual on Reddit says, particularly if they have a Youtube video to go with it.

One problem with debunking the faked landings myth is that it's not one conspiracy theory but a host of related ones. In some versions, the entire project was faked and no astronaut left Earth. In others, they went into lunar orbit but never touched down. In still others the Moon, like the Earth, is flat and landing is presumably impossible. As Dr Carpineti joked in response to the message: “Bold of you to assume the Moon is real.” Disproving a specific version can be a game of whack-a-mole.

Nevertheless, here is an overview of the problems with most or all variations of the idea the Moon landings – all six of them, because people tend to forget there was more than just one – were faked.

Too many people

It's easy to conduct a conspiracy for two. Both probably stand to gain a lot from keeping the secret, and if it leaks the one who did their part knows who to blame. It’s harder with a dozen conspirators, but we know it has happened, although even then someone often has a crisis of conscience, blabs while drunk, or is sloppy with incriminating evidence. However, the Apollo missions were one of the largest endeavors in human history. It is estimated 400,000 people were employed at some point on the project. 

Not all of these would have needed to know if the missions weren’t real. The people who designed and made the space suits, for example, could have been left to think their work would be used, although the precision that went into making them fit for the task would certainly have added to the cost.

Nevertheless, tens of thousands of people would have needed to be in on the secret, from the astronauts themselves to the filmmakers who would have had to fake the images and the clean-up crew for the returned command module. 

Most people have very little awareness of how many people were required for every piece of that first mission. For example, the film The Dish portrays the images from Neil Armstrong’s steps as being collected by a team of four at the Parkes Observatory, Australia. In fact, the Parkes team involved around two dozen people, each of whom would need to have been let in on the secret, lest they discover the signal was not coming from the Moon and reveal the truth. Moreover, the famous images were collected by a separate team at Honeysuckle Creek, while the Moon was too low in the sky for the larger Parkes facility, requiring even more people to be in the know. Other facilities worldwide were on standby.

The returned Moon rocks

The Apollo missions brought back 380 kilograms (840 pounds) of rocks and dust from the surface of different parts of the Moon. Any geologist with a promising-sounding research project can request a sample and many do. Projects that require large amounts of lunar material tend to be rejected, but those who can do the analysis they need using small slices are frequently granted access, and publish their results.

These slices have been exposed to lasers, reacted with reagents, and run through mass spectrometers. The results consistently demonstrate the rocks formed in an airless and largely waterless environment unlike anything on Earth, and have spent billions of years directly exposed to the solar wind. Unless thousands of geologists worldwide have been in on the scam, the rocks would have needed to be faked in a way that would be far beyond modern technology, let alone what was around 50 years ago.

It’s unlikely anyone could have even predicted the composition required to fake a Moon rock before the landing. Yet the samples returned by China’s Chang’E-5 are a good enough match, allowing for their different locations, to indicate both came from the same celestial object. One geologist has stated it would have been harder to fake the rocks than to actually go to the Moon. 

Others were watching

Although the lunar missions were scientific expeditions, national pride played a huge part. President John F. Kennedy was desperate to wipe off the embarrassment of the Soviet Union beating America with the first satellite and the first man in space. The Soviets would have loved nothing better than to see the US fail. If they’d had the slightest evidence Apollo 11 didn’t land, it’s absurd to think they would have kept it quiet. Their radio telescopes tracked each mission and would have had plenty of opportunity to pick up if the signal was coming from anywhere other than the Moon.

The objects left behind

Three Apollo missions left mirrors on the lunar surface off which lasers have since been bounced to measure the Earth-Moon distance with exceptional precision. At the time robot missions lacked the capacity to install them.  

NASA’s robotic lunar orbiters have photographed objects left behind at each landing site, but such evidence is considered fake by those who don’t accept the original evidence. However, in 2008 the Japanese SELENE probe observed the blast crater left behind by Apollo 15, expanding the list of people who would need to be in on the conspiracy still further.

The risk of faking it

A successful Moon landing was a huge boost to American national pride, but NASA and the entire US government knew there was a risk of failure. President Nixon famously prepared a speech in case Neil Armstrong and Buzz Aldrin died on the Moon.

Embarrassing as their deaths would have been, it would have been nothing compared to the discovery hundreds of billions were spent on a fake. Everyone in the chain of command from the President down to the astronauts would have known the consequences of a conspiracy being exposed. How many would have been mad enough to go along with the idea knowing that failure to perform any part of the charade perfectly would reveal the truth?

Why it matters

Studies of believers in conspiracy theories have shown that those willing to swallow one will believe others. This even applies to directly contradictory theories. People who believe Princess Diana was murdered on the direct orders of the Queen are more likely to also believe she is still alive somewhere, having faked her own death.

Though believing in claims the Moon landings were faked sounds harmless, they can be a gateway to more dangerous conspiracies with real-world consequences, from anti-vaccination beliefs to global warming and climate change denial.

Sadly, however, there may be no evidence that will shake the hard-core conspiracy theorists’ certainty. The only hope is to reach those who have yet to fall down this particular rabbit hole.

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Robotic probes have dived into the watery ruins of the Fukushima nuclear power plant and revealed that vital supporting structures appear to be damaged. While the discovery is not an immediate concern, it's feared it could become a major issue if another earthquake rocks the area.

Tokyo Electric Power Company Holdings (TEPCO) uses remote-controlled probes to explore the submerged depths of the nuclear power plant and keep tabs on how the massively expensive clean-up operation is going. 

According to an update [PDF] released on Tuesday, one of their robots recently took images of the Unit 1 pedestal, a supporting structure under one of the reactor cores that experienced a meltdown during the notorious 2011 nuclear disaster.

Associated Press reports that the 120-centimeter (47-inch) thick concrete wall of the pedestal was showing signs of significant damage at its base, exposing the steel reinforcement inside. 

The concern is that three of the reactors contain an estimated total of 880 tons of highly radioactive melted fuel debris. According to The Asahi Shimbun, TEPCO managed to obtain the first visual confirmation of the melted nuclear fuel in the Unit 1 reactor for the first time just last week.

A deposit, possibly of melted fuel, outside the pedestal. Image credit: TEPCO

The clean-up operation is still challenged with removing the fuel debris. If these support structures break, then it threatens to cause further headaches for TEPCO. 

Reports of the damage prompted the Governor of Fukushima Prefecture, Masao Uchibori, to ask TEPCO to immediately evaluate whether the structure could survive another earthquake, just like the one that prompted the catastrophe. 

The catastrophe occurred on March 11, 2011, when a 9.0 magnitude earthquake struck the east coast of Japan, creating a 15-meter (50-foot) tsunami that killed over 18,000 people along Japan’s northeast coast.

The devastating waves also struck the Fukushima Daiichi nuclear power plant, shutting down its power supply and vital cooling systems. This led to a meltdown in three of its reactors and sent significant amounts of radiation into the atmosphere. Considering the scale of the accident, it’s widely considered to be the worst nuclear disaster since Chernobyl in 1986.

The recently imaged spent fuel in the reactors is just one part of the problem, however. Following the incident, the plant was flooded with water. This produced around 1.3 million tons of wastewater that are stored in over 1,000 tanks at the site.

After a long and heated debate, TEPCO recently said it was going ahead with plans to dump this treated water into the Pacific Ocean, sparking anger from local fishing communities and neighboring countries. It might sound sketchy, but the proposal is safer than it sounds – and perhaps the only option on the table.

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There's expected to be around 13 million tons of stinky algae now populating the Great Atlantic Sargassum Belt. Image credit: Guajillo studio / Shutterstock.com

Ice covers around 98 percent of the Antarctic continent, shielding the vast majority of its land mass from sight. However, thanks to some incredible imaging techniques, we’re able to gain a deeper understanding of what the continent of Antarctica would look like without ice. 

The Bedmap2 was created back in 2013 using vast amounts of data on surface elevation, ice thickness, and bedrock topography collected by NASA and the British Antarctic Survey from satellites, aircraft, and surface-based surveys.

As the map shows, the naked land beneath the Antarctic ice sheet is a rugged land, covered in mountain ranges, gorges, and jagged terrain. Remarkably, one part of the bed found under the Byrd Glacier in Victoria Land is 2,870 meters (9,416 feet) below sea level, making it the lowest point on any of the Earth's continental plates.

"Bedmap shows, with unprecedented detail, the bedrock beneath the ice sheets of Antarctica. Before we had a regional overview of the topography, but this new map, with its much higher resolution, shows the landscape itself; a complex landscape of mountains, hills, and rolling plains, dissected by valleys, troughs, and deep gorges," Peter Fretwell, from the British Antarctic Survey, said in a statement in 2013.

One of the important tools used to scoop this data was an ice-penetrating radar instrument known as the Multichannel Coherent Radar Depth Sounder that’s able to determine ice thickness and subglacial topography.

Understanding the shape of this subglacial world is important as it impacts how ice is distributed and influences how it will melt in the face of rising oceans and air temperatures linked to climate change.

"Ice sheets grow because of snow, and like honey poured on a plate, spread outward and thin due to their own weight," Sophie Nowicki, an ice sheet scientist at NASA's Goddard Space Flight Center in Greenbelt, explained in another statement. 

"The shape of the bed is the most important unknown, and affect how ice can flow," she added. "You can influence how honey spreads on your plate, by simply varying how you hold your plate."

The Bedmap2 data reveal that Antarctica harbors 27 million cubic kilometers (6.4 million cubic miles) of frozen water that, if melted, would result in around 58 meters (190 feet) of sea-level rise. 

While the entire Antarctic ice sheet is not predicted to totally melt under current climate projections, it’s painfully clear that it is slowly thawing at a shocking rate. The latest estimates suggest the world's oceans are now rising by 4 millimeters (0.16 inches) each year as a result of thawing ice sheets in Antarctica and Greenland. This, they believe, is almost exactly the "worst-case scenario" put forward in the United Nations Intergovernmental Panel on Climate Change (IPCC).

To gain a better understanding of ice thickness and the world beneath Antarctica, scientists are now building the next-generation map, Bedmap3. 

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Dinosaur footprints were discovered during a chance encounter back in 2022 as a diner at a restaurant in China asked about some unusual pits on the stone floor. The person noticed there were a dozen evenly-spaced imprints along the outdoor courtyard of the Garden Restaurant in Sichuan Province, which were later confirmed to be dinosaur footprints around 100 million years old.

According to a new paper about the discovery, the pits had been seen back in the 1950s but were thought to be nothing special and smoothed over to even out the floor. At this time it was a home, but then three years ago it was converted into a restaurant, revealing the pits to the world once more.

“The footprints went unnoticed for so long, but once you know what they are, it’s hard to unsee them,” said Associate Professor Lida Xing from the China University of Geosciences, who worked on the discovery, in a statement. “The region has no skeletal record of dinosaurs, so these fossilised tracks provide invaluable information about the types of dinosaurs that lived in the area.”

Food Instagrammers catch a lot of flack for snapping their meals, but it seems there can be some perks to taking a moment to appreciate your surroundings before face-planting into your dinner. Using 3D scanners, a team confirmed the imprints were left by sauropods, plant-eating dinosaurs that grew to enormous sizes.

“We compared the size of the footprints with complete fossil skeletons,” Dr Anthony Romilio from the University of Queensland’s Dinosaur Lab said. “We also know the dinosaurs were taking quite short steps for such a large animal, with a walking speed of around two kilometres [1.2 miles] per hour.”

Using this information, they estimated that the owner of the footprints would’ve been around 10 meters (32 feet) long in life. Not quite the dizzying size of Patagotitan, which grew to around four times that, but still pretty big.

The “restaurant tracks” garnered global attention, featuring in the world press, and have now been described in a journal paper. They date back to the Lower Cretaceous, sitting in the Jiaguan Formation, and are the footprints of a Brontopodus type sauropod. 

With such an unusual location for discovering new insights about Earth’s history, it’s a reminder to always be on the lookout for hidden clues.

“It’s a testament to the value of being curious about our surroundings and paying attention to the world around us,” concluded Romilio. “For some lucky people discoveries can come from unlikely places – even while you're having a bite to eat.”

The study is published in Cretaceous Research.

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Bob Lee, 43, died after being found stabbed on the 400 block of Main Street in SoMa. Lee was chief product officer of MobileCoin, the former chief technology officer of Square, and the founder of Cash App.

Police have made no arrests or released any information regarding possible suspects.

April 4, 3:15 p.m. A 43-year-old man from Mill Valley died after being stabbed in San Francisco early Tuesday morning, officials said.

The San Francisco Police Department said in a news release that it responded to a report of a stabbing at 2:35 a.m. near a high-rise condominium building on the 400 block of Main Street at Harrison in SoMa.

At the scene, officers found the man with stab wounds, provided medical assistance and called first responders to the scene to provide additional life-saving measures, police said. The man, whose name hasn't been released, was taken to a hospital with serious injuries. Despite efforts to save him, he died.

The San Francisco Police Department said in a post to Twitter just after noon April 4 that it's asking anyone with information about the stabbing to call the department. Police have not made any arrests.

The police department reported 56 homicides in both 2022 and 2021, up from 48 in 2020. Since the start of 2023, there have been 12 homicides, according to the crime dashboard. At this time last year, there had been 10.

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Galaxies that appear to be similar in age to the ones described here.

NASA, ESA, CSA, Tommaso Treu, Zolt G. Levay

 

One of the goals of the Webb Space Telescope was imaging the earliest galaxies, giving us a new window into how our Universe evolved between the dense, hot material from the Big Bang and its star- and structure-filled present. And, almost as soon as the data started pouring in, things have looked very promising, with strong indications that we were picking up galaxies as they appeared only a few hundred million years after the Big Bang.

 

But a few uncertainties remained, as unusual conditions could potentially cause a much more recent galaxy to have features that make it look much older. That may be the case with a galaxy that would otherwise be the oldest ever detected.

 

On Tuesday, two papers were released that put the issue to rest, providing a full spectrum of four early galaxies and showing that they all clearly date from just a few hundred million years after the Big Bang. Imaging of the same galaxies shows that they're full of young stars that lack most of the heavier elements seen in today's Universe.

Full spectrum

Figuring out the age of early galaxies relies on finding a specific feature in the light the galaxies emit. Early in the Universe's history, most of it was filled with hydrogen atoms, which can absorb photons once they have sufficient energy to move its electron into other orbitals. Thus, although an early galaxy would emit broadly across the spectrum, there would be a sharp cutoff at what's called the Lyman break—any photons more energetic than that would be absorbed by the hydrogen.

 

Nearby, the Lyman break would reside in the UV portion of the spectrum. But its location gets red-shifted as photons travel across the expanding Universe, which stretches out the wavelength of light. As a result, the Lyman break travels across the entire visible spectrum and ends up in the infrared as we look further and, thus, earlier into the Universe's history. Finding the exact wavelength of the break can therefore tell us exactly how far the light traveled and how old the galaxy is.

 

The first papers that have come out on early galaxies relied on different filters that let in different areas of the infrared spectrum—researchers looked for galaxies that were present at longer wavelengths but disappeared at higher ones, suggesting that the Lyman Break was in the wavelengths let through by the lower-energy filter.

 

But this is a bit inexact, as the filters cover a range of wavelengths—we can't definitely know where within that range the break resides. And, by not capturing the details of the spectrum, it's possible we can miss information that indicates the feature we're seeing isn't actually the Lyman break, which could allow a closer galaxy to masquerade as something much more distant.

 

So, the new work uses the Webb's NIRSpec instrument to capture the full spectrum of a set of galaxies in a region of space that had earlier been imaged by the Hubble. The new papers focus on four of these: two previously identified by Hubble and two new from the Webb data.

Old and early

The spectra clearly show the Lyman break in all four of the spectra. The galaxies range in age from 460 million years after the Big Bang to just 325 million years after the Big Bang. The latter is the youngest galaxy ever to have its age confirmed through spectroscopy. (Though again, there are some indications that we've imaged some even closer to the Big Bang.) They're all also faint enough that we had never had an instrument that even could have obtained their spectra prior to putting the Webb in space.

 

What do these galaxies look like? They're relatively small, with about 108 to 109 times the mass of the Sun worth of stars. That makes them similar in size to the Small Magellanic Cloud, a dwarf galaxy in our local group. But they're forming stars at a pace that's roughly equivalent to the Milky Way's rate, which is about 10 times the rate of star formation in the Small Magellanic Cloud. So, star formation is occurring at a rapid pace.

 

The stars themselves appear to be extremely young, as well. Based on the imaging of the galaxies, about half the stars in them are less than 70 million years old—perhaps considerably less. There's also very little in the way of heavy elements around, which would have been generated by an even earlier generation of stars. At least one of the galaxies has less than 10 percent of the heavier elements seen in the Sun.

 

All of which is consistent with what we'd expect from the earliest galaxies in the Universe. And, critically, these properties are consistent with models of galaxy formation based on our current dark energy/cold dark matter model of cosmology—which you'd kind of expect, given that we had based galaxy formation models in part on the constraints of our understanding of cosmology.

 

That doesn't mean that cosmology is off the hook, though. There are still potentially earlier galaxies that need a more detailed look. There's also the matter of the frequency of the galaxies. Once we perform broader surveys of a region of space, it's possible that we'll find that more galaxies formed shortly after the Big Bang than we can account for.

 

Nature Astronomy, 2023. DOI: 10.1038/s41550-023-01918-w, 10.1038/s41550-023-01921-1  (About DOIs).

 

Webb confirms we’re looking at some of the Universe’s earliest galaxies

Chlorofluorocarbons, or CFCs, are entirely man-made gasses used in a variety of applications, including refrigeration, air conditioning, or as chemical solvents. They have been increasingly regulated by a series of international treaties since the 1980s.

The 1987 Montreal protocol, which has been unanimously ratified, restricted the release of CFCs to the atmosphere where they contribute to the destruction of the ozone layer: a region high up in the stratosphere which absorbs harmful ultraviolet (UV) radiation and protects life below.

The goal of the Montreal protocol was to induce a decline in the atmospheric CFC concentration through controlling, and increasingly restricting, the production of these chemicals.

This has worked well for many ozone-depleting substances, which is why the ozone layer is slowly recovering. And so the recent increase in atmospheric concentrations of five CFCs is quite surprising.

Our findings, while worrying, should be considered an early warning. The impact of all five CFCs on the recovery of the ozone layer is still small.

Nevertheless, we do not fully understand where they are coming from, so this could change in the future, and we should not ignore the cumulative effect of these emissions on human health and the environment.

The global picture

Our team has been analyzing air samples from all over the world, focusing on so-called "background" sites that are far away from the sources of these CFCs, or in fact any industrial emissions.

An example is the Cape Grim observatory on the remote west coast of Tasmania. This is the basis for our assessment of the threat these chemicals pose, as it reveals global trends in their atmospheric concentration.

Our main findings for the period 2010-2020 were twofold.

First, concentrations of CFC-13 and CFC-113a continued their previously observed – and puzzling – increase. Rising concentrations of CFC-113a even accelerated around 2016.

Second, concentrations of CFC-114a and CFC-115 were stable since the 2000s, while those of CFC-112a had even started to decrease. However, all of them began increasing around 2013-2014.

Global emissions of the five CFCs weighted by their impact on ozone depletion (a) and the climate (b). (Western et al., Nature Geoscience, 2023)

These observations, combined with additional knowledge about atmospheric circulation and how CFCs are removed from the atmosphere through chemical reactions, allowed us to estimate the global emissions of these five gasses.

Their damage to the ozone layer can be expressed through their ozone depletion potential, which states how much ozone would be destroyed compared to the same quantity of CFC-11, which is different for each CFC.

The result is a relief. Emissions between 2010 and 2020 only resulted in a very small loss of around 0.002 percent of global stratospheric ozone.

There is no time to relax, though, for two reasons.

All five CFCs are also potent greenhouse gasses and, once emitted, will remain in the atmosphere for decades to centuries. Their warming effect in 2020 was already approximately that of Switzerland's total CO₂ emissions. And if those emissions continue on their upwards trajectory, their contribution to climate change will expand too.

The persistence of these gasses in the atmosphere must be taken seriously: all emissions are a legacy for future generations to contend with.

Tracking down the sources

The first step towards avoiding future emissions is to find out where the current ones are coming from. There were already some hints in previous studies, which we gathered and combined with our own information, such as on the exact timing of when emissions started accelerating.

We found that three of the five CFCs (CFC-113a, CFC-114a, and CFC-115) can be produced during the manufacture of other chemicals, which is allowed under the Montreal protocol, most notably hydrofluorocarbons or HFCs. HFCs have replaced CFCs for many applications as an ozone-friendly alternative.

However, like CFCs, they are greenhouse gasses and their production is now being reduced in many countries under the 2016 Kigali Amendment to the Montreal Protocol, which could reduce climate-related warming by 0.5 °C.

It's likely that the CFCs are leaking out during the production process, where they are either used as a feedstock (a chemical ingredient to make another chemical) or as a result of incomplete conversion of the feedstock to the target chemical.

The production of HFCs really took off in developing countries after CFCs were banned in 2010, which is around the same time as the increase in emissions of these five CFCs.

The production of HFCs is predicted to further increase over the next few years, which could result in increasing emissions of these CFCs. CFC-113a is used to make at least one hydrofluoroolefin or HFO, which are alternatives to HFCs that don't heat the climate and may be used long into the future.

Despite HFCs and HFOs being more benign alternatives to CFCs, there may still be some cost to ozone during their production if CFCs continue to leak into the atmosphere.

We were unable to find a plausible source for the other two CFCs, CFC-13 and CFC-112a. The fact that their emissions are increasing and we don't know why is a concern in itself.

Time to revisit Montreal?

The Montreal protocol has been a huge success in mitigating emissions of ozone-depleting substances. Total CFC emissions are now only around 5 percent of their peak in the late 1980s.

Yet an increase in the atmospheric abundance of some CFCs is still at odds with the treaty's goals – and their elimination, by clogging leaks in industrial processes, could present an easy win to reduce these country-sized emissions of ozone-depleting and climate-warming gasses.

It will take careful consideration by countries signed up to the protocol to find the necessary controls for quashing these trend-bucking emissions.

In the meantime, we will continue to use our eyes in the sky to monitor the progress of a whole host of Earth-damaging gasses.

Luke Western, Research Associate in Atmospheric Science, University of Bristol and Johannes Laube, Honorary Lecturer, Centre for Ocean and Atmospheric Sciences, University of East Anglia

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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HUMANS HAVE LONG sullied the Arctic with industrial development—mining operations, oil and gas exploration, military bases. That’s contaminated the landscape with a bevy of toxicants, including radiological material, heavy metals, insecticides, and fuels.

That nastiness was often intentionally buried in frozen ground known as permafrost. In theory, as long as that ground remained frozen, the pollutants would stay locked away.

No longer. An alarming new paper in the journal Nature Communications estimates that between 13,000 and 20,000 contaminated sites are splayed across Arctic permafrost regions, with 3,500 to 5,200 in areas that’ll be affected by thawing soils before the end of the century. The region is already warming rapidly, more than four times faster than the rest of the planet. And that estimated number of sites is likely low, the scientists warn, because thaw might dramatically accelerate in some places. 

As permafrost degrades, it collapses, releasing buried contaminants that flow out in the melted ice. The ground sinks—often spectacularly and rapidly—dragging down aboveground infrastructure like fuel tanks and pipelines. Indeed, that was the suspected cause of a 2020 environmental disaster in Norilsk, Russia, in which 17,000 tons of oil leaked from a collapsed tank.

“The assumption is that permafrost is a hydrological barrier, and it will remain there forever,” says permafrost researcher Moritz Langer, of the Alfred Wegener Institute and Vrije Universiteit Amsterdam, lead author of the new paper. “That was the assumption for all of these very old sites—especially from the ‘70s, ‘80s, up until the ‘90s—when climate warming and the problem of permafrost thaw was not really on the radar of most people.”

Langer and his colleagues found that 70 percent of these sites are in Russia, with others across Alaska, Canada, and Greenland. Some facilities are abandoned and difficult to access and clean up. Others are still operational, and producing yet more toxicants to leak into the environment. (The new paper doesn’t distinguish, though, exactly which sites are which.) As the Arctic warms, expect industrial and military development to creep farther north, adding more contaminants while putting more people in contact with them. And the mushier the soil gets, the harder it will be to use heavy equipment to clean up the messes.

“This idea that somehow we have, functionally, a number of potential Superfund sites that were completely unknown until this paper, but could be mobilizing into the Arctic and potentially international environment, is pretty terrifying,” says Kimberley R. Miner, a climate scientist who studies permafrost contamination at NASA’s Jet Propulsion Laboratory but wasn’t involved in the new paper. “To see them take that idea and apply it to actual maps and get actual sites, with permafrost disturbance underneath, was so mind-blowing to me.”

Existing sites are already plagued by a slew of environmental troubles. Oil leaks come from both wells and from pipelines. Radioactive material is buried around military bases. Pesticides like DDT are packed in barrels, then buried. Mining operations are notorious for emitting heavy metals like mercury; other sites are full of arsenic, lead, and other highly toxic elements and compounds. Trucks and heavy machinery carry liquid fuels like diesel, which are prone to spill. 

Once the ground is no longer frozen enough to form a barrier, those contaminants will seep into rivers and ponds, corrupting highly sensitive ecosystems. “This, we think, could also be a dangerous situation for people living up in the high north,” says Langer, as the contaminants mix with drinking water.

That water will eventually empty into the ocean and ride elsewhere on currents. Toxicants can also get airborne: Indeed, the Arctic is already dusted with lead from burning leaded gasoline. Mercury, too, could escape mining operations by taking to water and air. “Mercury that came from the burning of coal and fossil fuels from a century or two centuries ago is still cycling through our biosphere,” says Kevin Schaefer, a climate scientist at the University of Colorado, Boulder, who studies permafrost contaminants but wasn’t involved in the new paper.

Human activity in the Arctic only exacerbates the thaw. Dark-colored roads absorb the sun’s energy, heating the soil. Digging up dirt and tossing it on top of snow darkens the whiteness that would normally bounce light off the landscape. Vehicle tires chew up the soil. “You already have rapidly changing environmental conditions,” says George Washington University climate scientist Dmitry Streletskiy, who studies permafrost but wasn’t involved in the new paper. “But then, of course, on top of those rapid changes, you have concentrated human presence—you have industry and infrastructure. So those are really focal points, where you in many ways amplify those changes associated with climate."

Oh, and the giant new Willow drilling project in Alaska that the Biden administration just approved? That’ll be on permafrost too. “Think about what it takes to establish a pipeline,” says Miner. “You're going to need a road. You're going to have people walking in and out, trampling the permafrost. All of that is going to lead to increased thaw and increased potential for contamination and disturbances to the very fragile tundra landscape. So it's just impacts upon impacts upon impacts.”

This new paper only considered gradual permafrost thaw. But permafrost can collapse much more rapidly, digging holes known as thermokarst. As ice becomes liquid water, it loses volume, forming a crater in which microbes produce the highly potent greenhouse gas methane. This further warms the atmosphere and accelerates permafrost thaw—a gnarly climatic feedback loop.

Adding yet more peril is that as the Arctic warms, wildfires are proliferating. If one sweeps through a contaminated site, it’ll send up plumes of toxicant-laden smoke. That will in turn exacerbate the thaw: Scientists have previously calculated that in north Alaska, thermokarst formation has accelerated by 60 percent since 1950, thanks to wildfires.

In other words, Langer says, their paper’s projection is “pretty conservative.” Some of the sites might thaw even earlier.

Permafrost is already deforming communities in the far north. Airport runways are sinking, roads are wrinkling, and buildings are crumbling. “It's no longer some ambiguous thing that might happen in the future—it's happening today, even as we speak,” says Schaefer. “If this infrastructure becomes damaged because of thawing permafrost, it's extremely expensive and extremely difficult to resolve. These areas are very remote. You can only do things in certain times of the year, mainly the summer.” 

If thermokarst opens a hole in your runway, for instance, it might cut off surrounding communities that rely on supplies brought in by plane. And if you can’t fly, you can’t get out of many places around the Arctic. “It's not like the Lower 48—if I don't make it to Denver, I'll fly to Colorado Springs,” says Schaefer. “These are all really key infrastructure, and it's really difficult to build and maintain.”

But this new paper is at least a step toward localizing the problem, directing governments to where cleanup might be required. Early scientific sleuthing like this is a start, but a fix will take putting a lot of boots on increasingly soggy ground. “In order to manage something, you have to measure it,” says Miner. The next step would take a massive push—one like the US Environmental Protection Agency began in the 1980s to clean up Superfund sites. But with such a patchwork of nations and corporations responsible for the mess, it’s not clear when—or if—that work would start.

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Recent research shows that the mass loss of lake-terminating glaciers in the Himalayas has been severely underestimated, due to the limitation of satellites in detecting underwater changes in glaciers. This has significant repercussions for the region’s future projections of glacier disappearance and water resources.

The study was published in the journal Nature Geoscience, and carried out by a global collaboration of scientists from the Chinese Academy of Sciences, Graz University of Technology in Austria, the University of St. Andrews in the UK, and Carnegie Mellon University in the United States.

The researchers found that a previous assessment underestimated the total mass loss of lake-terminating glaciers in the greater Himalayas by 6.5%. The most significant underestimation of 10% occurred in the central Himalayas, where glacial lake growth was the most rapid. A particularly interesting case is Galong Co in this region, with a high underestimation of 65%.

This oversight was largely due to the limitations of satellite imaging in detecting underwater changes, which has led to a knowledge gap in our understanding of the full extent of glacier loss. From 2000 to 2020, proglacial lakes in the region increased by 47% in number, 33% in area, and 42% in volume. This expansion resulted in an estimated glacier mass loss of around 2.7 Gt, equivalent to 570 million elephants, or over 1,000 times the total number of elephants in the world. This loss was not considered by previous studies since the utilized satellite data can only measure the lake water surface but not underwater ice that is replaced by water.

“These findings have important implications for understanding the impact of regional water resources and glacial lake outburst floods,” said lead author Zhang Guoqing from the Institute of Tibetan Plateau Research, CAS.

Revealing the ‘invisible’ glacier loss underwater. Credit: TPE

 

By accounting for the mass loss from lake-terminating glaciers, the researchers can more accurately assess the annual mass balance of these glaciers compared to land-terminating ones, thus further highlighting the accelerated glacier mass loss across the greater Himalayas.

The study also highlights the need to understand the mechanisms driving glacier mass loss and the underestimated mass loss of lake-terminating glaciers globally, which is estimated to be around 211.5 Gt, or roughly 12%, between 2000 and 2020.

“This emphasizes the importance of incorporating subaqueous mass loss from lake-terminating glaciers in future mass-change estimates and glacier evolution models, regardless of the study region,” said co-corresponding author Tobias Bolch from Graz University of Technology.

David Rounce, a co-author from Carnegie Mellon University, noted that in the long run, the mass loss from lake-terminating glaciers may continue to be a major contributor to total mass loss throughout the 21st century as glaciers with significant mass loss may disappear more rapidly compared to existing projections.

“By more accurately accounting for glacier mass loss, researchers can better predict future water resource availability in the sensitive mountain region,” said co-author Yao Tandong, who also co-chairs Third Pole Environment (TPE), an international science program for the interdisciplinary study of the relationships among water, ice, climate, and humankind in the region and beyond.

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In a groundbreaking development, Imperial College London physicists have recreated the historic double-slit experiment, which demonstrated light behaving as both particles and a wave, in time rather than space. By using materials that can alter their optical properties in femtoseconds, the team successfully fired light through a thin film of indium-tin-oxide, creating temporal “slits” for light to pass through. The experiment not only offers insights into the fundamental nature of light but also serves as a stepping stone for developing advanced materials to control light in both space and time. These materials could potentially contribute to new technologies and help study fundamental physics phenomena, such as black holes.

The experiment relies on materials that can change their optical properties in fractions of a second, which could be used in new technologies or to explore fundamental questions in physics.

The original double-slit experiment, performed in 1801 by Thomas Young at the Royal Institution, showed that light acts as a wave. Further experiments, however, showed that light actually behaves as both a wave and as particles – revealing its quantum nature.

These experiments had a profound impact on quantum physics, revealing the dual particle and wave nature of not just light, but other ‘particles’ including electrons, neutrons, and whole atoms.

Now, a team led by Imperial College London physicists has performed the experiment using ‘slits’ in time rather than space. They achieved this by firing light through a material that changes its properties in femtoseconds (quadrillionths of a second), only allowing light to pass through at specific times in quick succession.

Lead researcher Professor Riccardo Sapienza, from the Department of Physics at Imperial, said: “Our experiment reveals more about the fundamental nature of light while serving as a stepping-stone to creating the ultimate materials that can minutely control light in both space and time.”

Details of the experiment are published today (April 3, 2023) in the journal Nature Physics.

Project member Romain Tirole adjusts the equipment used in the study at Imperial College London. Credit: Thomas Angus, Imperial College London

 

The original double-slit setup involved directing light at an opaque screen with two thin parallel slits in it. Behind the screen was a detector for the light that passed through.

To travel through the slits as a wave, light splits into two waves that go through each slit. When these waves cross over again on the other side, they ‘interfere’ with each other. Where peaks of the wave meet, they enhance each other, but where a peak and a trough meet, they cancel each other out. This creates a striped pattern on the detector of regions of more light and less light.

Light can also be parcelled up into ‘particles’ called photons, which can be recorded hitting the detector one at a time, gradually building up the striped interference pattern. Even when researchers fired just one photon at a time, the interference pattern still emerged, as if the photon split in two and travelled through both slits.

In the classic version of the experiment, light emerging from the physical slits changes its direction, so the interference pattern is written in the angular profile of the light. Instead, the time slits in the new experiment change the frequency of the light, which alters its colour. This created colours of light that interfere with each other, enhancing and cancelling out certain colours to produce an interference-type pattern.

The material the team used was a thin film of indium-tin-oxide, which forms most mobile phone screens. The material had its reflectance changed by lasers on ultrafast timescales, creating the ‘slits’ for light. The material responded much quicker than the team expected to the laser control, varying its reflectivity in a few femtoseconds.

The material is a metamaterial – one that is engineered to have properties not found in nature. Such fine control of light is one of the promises of metamaterials, and when coupled with spatial control, could create new technologies and even analogues for studying fundamental physics phenomena like black holes.

Co-author Professor Sir John Pendry said: “The double time slits experiment opens the door to a whole new spectroscopy capable of resolving the temporal structure of a light pulse on the scale of one period of the radiation.”

The team next want to explore the phenomenon in a ‘time crystal’, which is analogous to an atomic crystal, but where the optical properties vary in time.

Co-author Professor Stefan Maier said: “The concept of time crystals has the potential to lead to ultrafast, parallelized optical switches.”

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