The science of getting Z’s has progressed rapidly in recent years. A growing body of research links poor sleep to increased risk of cognitive decline, a higher likelihood of Alzheimer’s disease, and even greater chances of developing heart problems. At the same time, wearables, like smart rings and watches, are transforming the way everyday people view sleep, turning their resting hours into rich datasets to pore over, sometimes to unhealthy obsessive levels. 

What’s still less understood, is how the subtle, everyday fluctuations in sleep quality that come from simply living a normal life can alter brain chemistry. People don’t live in controlled lab settings, and even the most avid bio-optimizer still has nights where quality sleep takes a backseat. Actually understanding how someone’s day-to-day sleep patterns affect their brain chemistry would require putting them in an MRI machine and collecting data over and over again, over long stretches of time to get a more holistic view. 

That’s exactly what Auburn University electrical and computer engineering graduate student Joshita Majumdar signed up for. Over 76 weeks, Majumdar slipped into the university’s 7-Tesla MRI scanner 104 times. That’s a level of commitment that would make even a stalwart Zen meditator fidget with frustrated boredom. Thankfully, Majumdar had a special companion to accompany her during the loud, cramped, 90-minute sessions: the hit television sitcom Friends.

Majumdar recalls how a screen in the machine would cycle through four 10-minute videos of the staple from the 90’s and early 2000’s, each made up of several different scenes clipped together. The idea was twofold. Majumdar needed something playing during the sessions that would keep her from getting bored, and Friends just happens to be her self-described “guilty pleasure.” It was also one of the first shows she connected with as an international student adjusting to her early days in the United States, so some scenes strike particularly nostalgic, emotional notes. And like any great sitcom, Friends runs the gamut from numbing brain-rot to tear-jerking sentimentality. That’s potentially a great backdrop for a study analyzing changes in brain chemistry.  

“If you’re happy, you watch Friends. If you’re sad, you watch Friends,” Majumdar tells Popular Science. “So all times [are] a good time to watch Friends, right?”

Past studies have looked at the way sleep variability affects brain chemistry, but many of those involve intentionally depriving the subject of sleep. This longer-term approach takes a more subtle approach that should better reflect the nuances of everyday life. 

“This is a person living her life, going through normal ups and downs and we are seeing how brain chemistry responds to that,” Majumdar’s advisor and Auburn University Electrical and Computer Engineering Professor Gopikrishna Deshpande said.  “That’s what makes this dataset so powerful. It’s not artificial. It’s not forced. It’s real.”

The journey to 104 brain scans 

Majumdar grew up in Kolkata, West Bengal, India, and moved to the U.S. in 2016 to pursue a master’s degree in engineering at the University of Georgia, with an emphasis on mechanical engineering. Early on, she became interested in how different environmental factors affect brain function. And while she was busy pushing forward with her rigorous academic work, she also dealt with occasional homesickness, living in a new country thousands of miles away from friends and relatives. 

Around that same time, Majumdar says she started watching Friends to see what all the fuss was about. People around her seemed obsessed with the show, but she hadn’t seen it, and initially didn’t really understand the hype. Eventually, she went back to the show with fresh eyes and everything clicked. The sarcastic Chandler Bing (Matthew Perry) and affable actor Joey Tribbiani (Matt LeBlanc) are among her favorite characters.

“I gave it another try, and then I was like, oh no, this is fun,” Majumdar said. “And then it became a guilty pleasure.” 

When it came time to pick a test subject for this new, lengthy MRI study, Majumdar says Dr. Deshpande asked her if she’d be up for volunteering. Majumdar has some experience with MRI machines from past projects, enough to know that she wasn’t prohibitively claustrophobic or bothered by the machine’s loud industrial noises. Still, nothing she’d done before this could compare to the endurance and commitment it would take to see this through. The team decided not to commit to a set number of scans at the onset, and took it day by day to see how much the grad student could handle. 

“We said, like, ‘Okay, we’ll take one day at a time, one week at a time, and see how far we can pull it through,” Majumdar explained. 

Don’t sleep on Friends  

Majumdar was the one who pitched playing Friends episodes in the machine. She compiled four 10-minute videos, each made up of different scenes from various episodes. The material ran the gamut in tone, with the goal of eliciting a range of brain responses. One particularly strategic choice was to include clips of episodes aired around Thanksgiving. These fan-favorites tend lean heavily on themes of family, friendship, and camaraderie. Friends, in other words, was meant to roughly simulate the backdrop for Majumdar’s everyday life brain state. 

“In a task-based MRI, we are giving a particular stimulus, so we kind of have an idea what we are trying to activate in the brain,”  Majumdar said. “But in a naturalistic run, it’’s kind of like you’re putting yourself into a real-world situation.” 

But that wasn’t all. Every session, the team would also play a roughly four-minute music video to the song “Love You Zindagi,” from the 2016 Bollywood film Dear Zindagi. Similar to the Thanksgiving episodes, this video was thoughtfully selected for its depiction of friends and family. It also helps remind Majumdar of home. 

“I have left my friends and family back in India,” Majumdar said. “So depending upon what my emotions are on that day, I used to really connect to it differently each day.”

Majumdar and her colleagues quickly settled into a routine for their MRI odyssey. She would come to the university’s neuroimaging center on Tuesdays and Thursdays, typically around 7:30 in the evening. She had the choice of that later time slot or first thing in the morning, but chose the former because she says she isn’t really a morning person. That choice came with some trade-offs, though. 

Early on, she discovered that eating a meal immediately before entering the machine made her feel dizzy. After one fraught experience, she made a point of giving herself a gap of 90 minutes to two hours after eating before going into the scanner. Coming in later at night, especially after a long day of PhD work, also meant she sometimes had to fight the urge to fall asleep. Even though she was stuck in the machine for 90 minutes at a time, the tests required that she keep her eyes open for the vast majority of it. That struggle is partly what makes subsequent findings all the more interesting. 

“Sometimes I was a little bit sleepy, but that’s part of it,” Majumdar said. “And that’s the thing that we wanted to bring out through this research: that you are in a very natural setting. You’re not in a kind of a forced experiment where you are either sleep-deprived or put under some conditions that might evoke a different brain response. We really wanted to look at the real-world condition where I’m just living my life, and in parallel I’m getting scanned and seeing how the brain chemistry responds to it.”

In addition to sitting in the MRI machine, Majumdar logged everything she ate and wore a sleep-tracking ring. With all of that data, the team was able to match each night’s sleep metrics with the next day’s scan and compare patterns over time. Though there’s still data being combed through, they’ve already found an important connection: across the 104 sessions collected over 76 weeks, nights with less deep sleep and more light sleep tended to be followed by higher glutamate levels the next day. Glutamate is an amino acid that acts as a kind of chemical messenger in the brain. In a previous university blog post, Majumdar compared this finding to the brain flushing out byproducts that build up during active, wakeful moments, allowing for a more restful night’s sleep.

“You wake up with a fresh mind,” she said. “But if that process is blocked, it’s going to hamper you the next day.”

But is she sick of sipping coffee at Central Perk?

Majumdar’s work in this area has only just begun. Moving forward, she and her colleagues hope to bring on more study participants  to make the dataset even richer, though they’ll likely make adjustments so that each participant doesn’t have to go in for scans quite as often as she did. 

Eventually, she says she also hopes to use AI and other tools to try and extract the feelings and emotions experienced during those MRI sessions (and during certain Friends’ moments) to get a better sense of what’s happening in the brain when certain feelings are evoked. 

Miraculously, even after watching the show in a cramped, rumbling tube for 18 months, Majumdar says she still isn’t sick of Friends. When asked if she can still watch the silly sitcom without getting bored, Majumdar responds with an emphatic, 

“Yes, definitely.”

The post Classic sitcom ‘Friends’ helps grad student endure 104 brain scans appeared first on Popular Science.

Much like the earworm “The Song That Doesn’t End” from Shari Lewis’ Lamb Chops’ Play-Along, a new soft robot does not stop…curling up and jumping. A team of mechanical engineers from North Carolina State University say that they’ve created the bracelet-shaped bot that moves indefinitely when it’s exposed to infrared light. 

Called a Ring Leaper, the teardrop-shaped machine is made of a liquid crystal elastomer ring with a more rigid aluminum V-shaped tail at the end. The ribbony-soft part contracts and tightens when exposed to the light. It keeps curling in, getting tighter and tighter (and building up more energy) until it reaches a “critical threshold” and folds onto the metal part. At that point, the V-shaped aluminum aggressively snaps downward, smacking the ground and launching the robot forward or into the air. 

But Ring Leaper doesn’t quit after that. As soon as the bottom part snaps down, the ribbon part of the body will start tightening around itself all over again. This team of researchers at North Carolina State University says this results in a new kind of robot system that “autonomously stores, releases, and recycles elastic energy.” 

Their mechanical jumping bean can leap either straight up or forward, depending on the angle of the V-shaped bottom part. And it has some hops. The tiny Ring Leaper can achieve a vertical leap exceeding 80 times its own body height. That would be the equivalent of LeBron James (six foot nine inches) leaping 540 feet into the air. That’s taller than a 50-story building. The team recently published their findings in the journal PNAS.

Ring Leaper can hop over hurdles and swim like a frog 

Ring Leaper wasn’t limited to a sterile lab environment. It can tackle small obstacles like grass, rocks, and mulch. It can even swim… sort of. One of the tests involved placing Ring Leaper into a shallow tub of water before shining infrared light on it. On cue, it started its curling-and-jumping routine, but this time it would slightly pop out of the water and gradually wade forward like a frog. Ring Leaper was also able to clear a pair of tiny hurdles, even after slightly tumbling over the first one. When tasked with jumping headfirst into a tall wall, the robot dutifully complies, then whips backward and continues jumping back in the direction it came from, in a kind of mirroring effect. None of this, it’s worth saying, is really programmed or coded instruction. Ring Leaper just jumps.

Controlling Ring Leaper’s mode of movement is also pretty low-tech. The team can dictate whether it jumps straight up, propels itself forward, or goes somewhere in between by adjusting the angle of the V-shaped aluminum tube at its base. A V-shaped angle wider than 120 degrees will result in a crawling motion. Reduce that angle to 90 degrees, and it will leap forward like a frog.  A narrower opening below 50 degrees results in a dramatic vertical jump. Each of those movements is also determined in part by the strength of the infrared light shining at it. More light equals more power. 

“We could also improve the robot’s jumping distance by adding a small amount of weight to the rounded end of the teardrop,” Fangjie Qi, a North Carolina State postdoctoral researcher and study co-author said in a statement. “This changes the robot’s center of mass and leads to a more powerful and stable forward motion – much like a swimmer leaning forward as they dive off the starting block.” 

So what’s this forever jumping robot actually useful for? Well, for now, nothing. Like a great deal of important scientific research conducted over many decades, the team essentially made it because they could, with no obvious commercial or practical application. That still doesn’t mean it’s completely useless. The proof-of-concept robot marks an advancement in self-resetting jumping, which could help other engineering teams who are looking to integrate these findings into future robotic navigation methods. 

The post Bracelet-shaped robot just keeps jumping appeared first on Popular Science.

What began as a routine police response to a reported break-in turned into a brief standoff between nature and technology. Last week, law enforcement in the city of Kirkland, Washington (just northeast of Seattle) responded to a 911 call from a resident reporting loud banging inside their home. Officers arrived expecting a human intruder, but were instead greeted by a more literal cat burglar: a trapped and confused bobcat. 

Not wanting to risk a claw to the face, the officers backed out and reassessed the situation. They ultimately decided to deploy a remote-controlled drone into the house, to monitor the feline intruder from a safe distance. Video captured from the drone’s perspective and released on Facebook, shows the frustrated bobcat standing by a staircase, growling and arching its back at the hovering machine. After a brief standoff with the buzzing, metal alien, the bobcat carefully retreated, sidestepping into an adjacent empty room.

Police were then able to close their door and keep the bobcat isolated until a team from the  Washington Department of Fish and Wildlife arrived. Wildlife officials then sedated the cat, loaded it into a crate, and transported it to nearby Forbes Creek. The feline was then released back into the wild, startled but safe. As for how a bobcat ended up in the house in the first place, Kirkland Police believe the adventurous intruder climbed a tree and jumped through an open window, possibly lured in by the resident’s indoor cat. Both the owner and its likely shocked cat were unharmed, according to the police. Thankfully, curiosity didn’t kill this cat.

The Kirkland Police Department did not immediately respond to Popular Science’s request for comment. 

The aerial deployment was made possible by a public safety drone program the Kirkland Police began in 2022. Today, they reportedly maintain five drones and have 17 FAA-licensed pilots ready to operate them. The typical use cases for those drones include search and rescue, tactical search, scene documentation, and, apparently, bobcat removal. 

Drones are changing the way police surveil wildlife…and people 

Drones and robotic dog-like quadrupeds are reshaping how local communities approach wildlife management. In Japan, authorities deploy a combination of camera-equipped drones and robotic Monster Wolves to locate and deter bears following a record spike in human-bear encounters driven by urban sprawl and declining farmland. In the United States, police in Santa Fe, New Mexico, recently used an aerial drone to track an errant bear wandering near a school. Expanded drone programs are also playing a greater role in locating lost or missing pets. Just last month, firefighters in t Florida used a remotely controlled drone to find an overly adventurous dog trapped in a storm drain. 

But this increased prevalence of drones comes with other, more controversial concerns as well. Police forces around the country are ramping up “drones as first responder” programs, which civil liberty critics say could introduce unreasonable surveillance. Law enforcement around the country has already used these drones to monitor political protesters. Meanwhile, Immigration and Customs Enforcement (ICE), is reportedly interested in using Boston Dynamics’ quadruped robot “Spot”  to aid in immigration operations. Private security companies like Flock and Axon are also investing heavily in aerial surveillance drones. 

The post Home-intruding bobcat no match for police drone appeared first on Popular Science.

With the dog days of summer nearing an end, many are counting down the days until they can give the darker clothes in their wardrobe a bit more love. Though plenty of people flout seasonal rules and wear all-black year-round, light-colored fabrics are typically the better choice during  hotter months because they reflect sunlight and can help keep us cool. This heat-reflecting logic is also partly responsible for the old decree, “don’t wear white after Labor Day!” But what if fashion choices weren’t dictated by the weather? A team of researchers from China and Australia believes they may have cracked that code, and it starts with a rich purple fabric.

The researchers, hailing from Zhengzhou University and Adelaide University, set out to create a dark-colored material that was also effective at keeping people cool. They created an entirely new fabric made of a purple metal-organic framework and zinc oxide nanoparticles. The metal-organic framework which absorbs green light from the sun and gives the purple color, while the zinc oxide nanoparticles which reflect sunlight and radiate heat away. 

The material performed exceptionally well during testing. It reflected an average of nearly 88 percent of sunlight and stayed up to 11 degrees Fahrenheit cooler than conventional purple cotton outdoors. It was notably even 7.6 degrees cooler than white cotton. In a world where deadly hot summers are becoming more common, research suggests materials like this could provide outdoor workers with some much-needed relief. 

“We have traditionally had to make a choice between cooling performance and appearance,” Adelaide University materials engineer Jun Ma and study co-author said in a statement. “Our research shows that we can have both. We can make a fabric that looks purple, but at the same time reflects most of the sun’s energy and releases heat very efficiently.”

The team published their findings in the journal Small. 

Why do light colors feel cool?

Generally speaking, lighter colors are better bets for staying cool because they reflect more sunlight. White or unpigmented materials are the best at beating heat, whereas dark black material will feel the hottest.  This same idea applies to building and construction materials as well. Purple, while obviously dark, is also a unique choice for the research because it strongly absorbs green light, which is one of the strongest parts of the solar spectrum. 

Caveats are in order, though. Color isn’t the only factor in staying cool. Clothing material and fit are just as important, if not more so. Loose, breathable garments like cotton or linen allow far more airflow than tighter clothing. That’s why Bedouin nomads in the North African desert can wear mostly all black without collapsing from heat exhaustion. Still, all else being equal, lighter colors make for a cooler experience.

Making a cooling, purple fabric 

To create the fabric, the team combined a purple ZIF-67 metal-organic framework with zinc oxide nanoparticles. Using electrospinning, they spun the mixture into purple thermoplastic polyurethane fibers, which were then woven into fabric. They then cut the material into two-inch squares and exposed them to direct sunlight on a sunny day in Zhengzhou, China, alongside control squares of standard white and purple cotton.

The revised material reflected an average of 87.6 percent of solar radiation. In terms of overall cooling, at least in these tests, it was a resounding success. After a full day baking in the sun, the fabric remained 7.6 degrees cooler than white cotton and 11.2 degrees cooler than traditional purple cotton. The fabric also  achieved these thermal gains without sacrificing practical performance, and  was flexible, stretch-resistant, and highly breathable, allowing moisture to evaporate effectively rather than trapping sweat. It also maintained both its rich color and cooling properties after 50 wash cycles. Furthermore, UV accelerated-aging tests (simulating roughly 108 days of intense sunlight exposure) showed that the  cooling performance did not degrade over time.

Using science to stay cool in a warming world 

It’s still early in the process, but the team believes their new approach could make darker-colored materials less off-putting during warmer weather. While that’s potentially great news for all the goths out there, the researchers emphasize far more practical applications as well. These refined fabrics could be used to make workwear for construction workers, farmers, and others who endure long hours baking in the sun. For outdoor laborers, even modest cooling relief can make a life-saving difference.

“The long-term opportunity is to move beyond the idea that cooling fabrics have to be white,” Adelaide University Chemical Engineer PhD candidate and paper co-author Yangzhe Hou said in a statement.

This summer’s heat has moved from unpleasantly hot to deadly in many parts of the world, and it’s likely a sign of more to come. Both the fashion industry and the general public are already adapting to this brutal new reality. A 2022 New York Times report noted a marked rise in sales of shorts and sandals alongside a sharp decline in fleece and heavy outerwear in recent years, a shift attributed in part to rising global temperatures. Similarly, recent efforts to normalize wearing shorts in office settings and the gradual removal of neckties reflect a workplace culture adjusting to a hotter climate.

The new purple fabric research also joins a now lengthy list of other attempts to apply science and technology to make clothing cooler. An assortment of (often more expensive) cool-tech clothing brands with names Coolcore and Iso-Chill have gained popularity, promising to beat the heat. Kontoor Brands, which owns blue-jean giant Wrangler, even made an Insta-Cool shirt that used phase-change material initially used by NASA astronauts to stay cool. 

The post New fabric stays cooler than white cotton—and it’s purple appeared first on Popular Science.