Today, you’ll learn about how a drug that helps in human organ transplants might be able to extend the lives of man’s best friend, the airline industry's potential but difficult switch to hydrogen fuel, and how a high school student is transforming prosthetics with brain waves.
Today, you’ll learn about how a drug that helps in human organ transplants might be able to extend the lives of man’s best friend, the airline industry's potential but difficult switch to hydrogen fuel, and how a high school student is transforming prosthetics with brain waves.
All dogs go to heaven.
Planes, planes, planes.
Mind over matter.
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Find episode transcripts here: https://curiosity-daily-4e53644e.simplecast.com/episodes/rapamycin-for-rover-h-fueled-flight-mind-controlled-arms
NATE: Hi! You’re about to get smarter in just a few minutes with Curiosity Daily from Discovery. Time flies when you’re learnin’ super cool stuff. I’m Nate.
CALLI: And I’m Calli. If you’re dropping in for the first time, welcome to Curiosity, where we aim to blow your mind by helping you to grow your mind. If you’re a loyal listener, welcome back!
NATE: Today, you’ll learn about how a drug that helps in human organ transplants might be able to extend the lives of man’s best friend, the airline industry's potential but difficult switch to hydrogen fuel, and how a high school student is transforming prosthetics with brain waves.
CALLI: Without further ado, let’s satisfy some curiosity!
[SFX: Whoosh/Intro Music]
CALLI: Nate, you know how much we all love our dogs.
NATE: Some of us a little too much...
CALLI: Oh, you mean like me? Because of my new puppy? Nate, you can just say it.
NATE: Okay yes, I mean you.
CALLI: Well, I can’t deny that. But I bet those folks, whoever they are, will be really excited when they find out that a drug derived from fungus on Easter Island could extend dogs’ lives by up to twenty-five percent!
NATE: A drug made from fungus?... From Easter Island? Why does this feel like the beginning of a sci-fi movie...
CALLI: It’s called rapamycin and it’s stone cold science FACT. A Canadian research team discovered it nearly fifty years ago while on an expedition in Easter Island.
NATE: The island with all those big head statues?
CALLI: That’s the one! The island itself is a tiny spec in the South Pacific, and the goal of the expedition was to study the native people who lived there. And one researcher in particular, Georges Nógrády, wanted to figure out why the people of the island had such low rates of tetanus infection.
NATE: What would make him even think of that?
CALLI: Two big factors - the first being that horses greatly outnumbered people on the island. And previous data told us at the time that tetanus bacteria was often found in areas with high horse populations. So, like, what’s up with that?
NATE: Suspicious.
CALLI: The second factor was that most of the people were walking around barefoot, which is a great way to pick up tetanus spores. They only need a super small wound to get into your system.
NATE: But, wait, the people didn’t get tetanus often? Meanwhile, they’re essentially living on “tetanus island.”
CALLI: You would think so, but Nógrády only found one instance of tetanus in a whopping sixty-seven soil samples. But what he did find plenty of was ...
NATE: Rapamycin?!
CALLI: You got it! I guess technically he himself didn’t find it, but a team at Ayerst pharmaceuticals did. Rapamycin was eventually cleared by the FDA for use in humans because it works as a pretty powerful immune system suppressant.
NATE: Suppressing your immune system doesn’t sound like a good thing.
CALLI: It has its benefits. Like, when it keeps your body from attacking organ transplants.
NATE: Oh wow, so this is a pretty powerful drug.
CALLI: Yeah. It actually has a lot of effects, depending on what you’re hoping to use it for, which means it’s useful, but it can have side effects. It can fight certain fungi in the human body, but also keep cells from multiplying.
NATE: Once again, these don’t sound like good effects...
CALLI: Well, a classic type of cell that multiplies fast is cancer, and it actually has some good results against solid-tumor cancers. But, it really depends on the specific medical situation and the person taking it.
NATE: Okay, cool. So, it’s an immunosuppressant with potential cancer benefits. But what about dogs?
CALLI: Sorry, sorry! Okay, early tests of the drug on dogs and mice have shown pretty remarkable anti-aging effects. Most notably for mice in the heart, ovaries, and brain. Some studies also showed it boosted their immune systems against cancer and COVID-nineteen.
NATE: But if it’s an immunosuppressant, how does it also boost the immune system?
CALLI: Basically, in the right doses, the qualities of rapamycin that keep cells from multiplying, or suppress the immune system, can be used to “reset” the immune system by decreasing chronic inflammation, and keeping potentially harmful cells at bay.
NATE: Ah, very cool.
CALLI: Studies on mice have shown that rapamycin treatment can result in raising their average life span by twenty-five percent. Which, for say a twelve year old dog, would mean they could live to fifteen years!
NATE: So many more memories! And cuddles!
CALLI: Lots more cuddles! The University of Washington is currently underway on the Dog Aging Project - a study of six hundred dogs to see how rapamycin’s effects shift depending on age, breed, size, and so on.
NATE: Hopefully it shows useful results. Either way, dog-lovers around the world rejoice!
CALLI: I know I will.
NATE: And you said earlier that rapamycin was already approved for use in humans with organ transplants? But what about the potential cancer treatment?
CALLI: Yes! Researchers believe further study could lead to use for cancer treatment. Not to mention chronic heart issues, and even help with skin aging.
NATE: Useful little guy!
CALLI: What we need more information on is its varying levels of toxicity. Actually, the dog studies could prove useful about how rapamycin reacts with the human body. We share quite a lot of commonalities in the way we age. Like, we have a lot of the same age-related diseases.
NATE: Dogs helping us fight cancer. Man’s best friend forever.
[SFX: Whoosh/Intro Music]
NATE: Calli, you know, I just got back from a little vacation.
CALLI: Yes, and nobody here is jealous, so keep bringing it up.
NATE: Great! Will do. Anyway, I had this thought on the plane ride home. We’ve talked on the show about how we probably won’t use fossil fuels in planes forever. We’ve mentioned the potential for electric planes ...
CALLI: But they’d need to make some serious breakthroughs in battery tech to make that happen, right?
NATE: Yes! But we’ve never talked about the potential for liquid-hydrogen fuel. So, I looked it up, and new research and engineering breakthroughs are bringing the possibility of liquid-hydrogen fueled flight closer to a reality. If these researchers are successful, they could drastically reduce our emissions from air travel, and dramatically change modern airplane design.
CALLI: Why would we even want liquid-hydrogen planes? I know our kerosene jet fuel isn't perfect, but it is pretty ubiquitous.
NATE: The aviation industry is responsible for 2.4% of global emissions, and hydrogen power has the potential to be nearly emission free.
CALLI: That would be great! But is hydrogen really new technology? Airships were using it over a hundred years ago ... You’re not suggesting we follow in the footsteps of the Hindenburg, are you?
NATE: Of course not! Though, side note, hydrogen airships COULD come back, with updated safety technology. But anyway, that’s buoyant, gaseous hydrogen. We are talking about liquid hydrogen cooled down to about negative 423 degrees Fahrenheit. The liquid is more energy-dense, and you don’t need super strong tanks to handle pressure, just insulated tanks to maintain the temperature.
CALLI: So we are all going to be flying to Denver on a big ice box?
NATE: Actually, something close. While they won’t be flying rectangles, plane design will have to change a lot. We'll need more fuel, so we won’t be able to store it in the wings. This change will usher in a new era of aviation design and creative problem solving.
CALLI: But have we used this as fuel before? Wait, didn’t Sputnik use liquid hydrogen? Wait, will the new designs be rockets?
NATE: That’s true, but no. Current commercial airliners typically use jet engines, which are propelled by the combustion of the fuel, and use oxygen from the air around it to feed those flames. For hydrogen-fueled flight, one of the most compelling ideas is to use a fuel cell. These combine oxygen and hydrogen in a chemical reaction that creates electricity. An awesome thing is the only emission is a little bit of heat, and water. Using these fuel cells could power the electric plane engines we’ve talked about in the past.
CALLI: Well what’s holding us back!?
NATE: For starters? Something pretty mundane: the supply chain. The infrastructure to create, store, transport, and re-fuel with super-cold liquid hydrogen, all while avoiding any potential explosions, is a ton of effort.
CALLI: Well that’s like our electric superhighways for cars, you just have to invest in infrastructure.
NATE: Well even if you solve the supply chain problem, the storage problem extends to onboard the plane. Liquid hydrogen has three times the power of kerosene by mass, but it requires four times the volume for the same output. It’s powerful by weight, but it’s big! So you have to store massive amounts of the fuel onboard.
CALLI: And that affects the design?
NATE: Well, designers will have to get creative. FlyZero has tried twenty-seven different configurations including a plane with two fuselages, one for passengers and one for hydrogen fuel.
CALLI: Fuselage. That’s the body of the airplane. So, two bodies?
NATE: Yep! And Airbus is experimenting with a more conventional plane and hopes to have something operational by 2035. Meanwhile one of my favorite designs is from a team of students and researchers from Delft University who recently tested a radical new plane called the Flying V.
CALLI: Ooh like the guitar Lenny Kravitz plays sometimes?
NATE: Exactly like that. The passenger cabin, cargo hold, and fuel tanks are integrated into a single large V structure that blends fuselage and wing into one smooth construction. It's like the entire plane is a wing. Not only does it have more room for fuel, it's more efficient too.
CALLI: Does the flying V need a new landing V airport, though?
NATE: While it could use our airports, there would be some sacrifices. Mainly, you’d lose two thirds of cargo volume. Passengers could have their luggage, but airlines would lose money transporting other cargo.
CALLI: Kind of all a moot point though if we can’t get the fuel for it.
NATE: Much of the industry agrees. That’s why there is a big call for governments to jump in and help solve the liquid hydrogen production, transportation and fueling issues. They’re endemic to the industry, and their solution is going to require a lot of collaboration and creativity.
CALLI: But if we could figure it out, we could massively reduce transportation pollution.
NATE: Absolutely, and some of the first liquid hydrogen flights have already flown, just not at commercial scale.
CALLI: Well let's get going! And then next time you take a vacation, two things will be different.
NATE: Two things? Hydrogen fuel, and...?
CALLI: You’ll invite me!
NATE: (realizing) Ahhh!
[SFX: Whoosh/Intro Music]
CALLI: Nate, we’ve got an incredible story today about a young man who has done more in just 17 years than many people do in a whole lifetime.
NATE: I love these kinds of stories. It really proves you can do anything, regardless of your age. Who is he and what has he been up to?
CALLI: Benjamin Choi, a Virginia 17-year-old, is not only a nationally-ranked squash player and published writer, but he spent the pandemic building a brain-controlled prosthetic arm that is far cheaper than anything on the market. It doesn't require invasive surgery and could make a world of difference for millions of American amputees.
NATE: That's incredible. But how do you even go about saying to yourself, alright, I’m going to make cyborg arms while other teenagers are playing Fortnite and making TikToks? Reminds me of when they created limbs for Anakin to be Darth Vader. Wait, is Benjamin on the dark side?
CALLI: (Laughs) Benjamin is all good, and Star Wars was actually part of his inspiration! A few years ago he saw an episode of 60 Minutes about prosthetic limbs controlled by the brain, and it seemed like something from that “Galaxy far far away.”
NATE: Controlling artificial limbs with the mind? How would you even go about doing that?
CALLI: Right now, it takes risky open brain surgery. But, Benjamin started working to find a better way. In 2020 he created his own lab on the ping pong table in his basement. He used his sister's $75 3D printer and started creating parts and rubber banding them together.
NATE: That's incredible. Is he still working on improving that first arm?
CALLI: He’s already made more than 70 prototypes and has upgraded from rubber bands to engineering grade materials that can withstand a lot more abuse. But the more impressive part is the system he created to control the arm.
NATE: Is it like Alexa? “Arm, please move to the left.”
CALLI: Well you can control it with head motions and blinks, but Benjamin also created a system that uses an EEG, a machine that scans electrical brain waves, to control the arm, all without that invasive surgery.
NATE: You’re telling me he's picking up the electrical signals of the brain? But how would you interpret those?
CALLI: The system uses two electrodes, one on the earlobe, and one on the forehead. The electrode on the forehead picks up the brain waves and sends them to the arm via bluetooth.
NATE: But can an arm read brain waves?
CALLI: Benjamin’s can. That's all thanks to the work he put in creating 23,000 lines of code, with 978 pages of complex math and 7 sub-algorithms to make an artificial intelligence model that learns continuously and deciphers your brain waves as arm movements. Most previous AI models aimed for about 74% accuracy with deciphering, but Benjamin’s is 95% accurate.
NATE: That’s an incredible leap!
CALLI: It's a big deal and the brain reading code alone could help people control wheelchairs or improve communication for people with ALS.
NATE: But how did he get the right data for the AI to understand brain waves and hand movements?
CALLI: He had 6 adult volunteers wear electrodes as they went about clenching and unclenching their fists. It helped the AI learn what our brain is doing when we move our arms, and like I said, it only gets better with continued use.
NATE: So, this is all impressive. But it has to cost a lot of money to make this kind of thing, right?
CALLI: For a long time, it did. The World Health Organization says that 9 out of 10 people who need assistive products like prosthetics don’t get them because of the high cost and lack of availability. Even the most basic prosthetics today cost thousands of dollars, and the brain-controlled ones approach half a million dollars. But by using readily available materials and affordable 3D printing, Benjamin’s costs only about $300 to manufacture.
NATE: Incredible, so what’s next? I heard there are about 185,000 amputations a year, this could be huge for all those people hoping to regain some function.
CALLI: Well, Benjamin is working to figure out how to attach the arm to the body. But he’s finally getting some help. Benjamin has already won funding to continue the research with MIT professors, and he earned a manufacturing grant as well as top prizes at a slew of science competitions.
NATE: I can’t wait to see where this goes.
CALLI: Me neither. Benjamin is a science inspiration to us all.
NATE: High five to that.
[SFX: Whoosh/Intro Music]
NATE: Let’s recap what we learned today to wrap up. Rapamycin - a drug made from a fungus found on Easter Island - could have remarkable anti-aging health benefits. With some estimating it could increase a dog’s lifespan by up to twenty-five percent, a large-scale test study is now underway to determine its proper use in man’s best friend.
CALLI: New research is bringing hope to the future of efficient and environmentally friendly liquid-hydrogen fueled airplanes. Everything from aircraft design to methods of fueling the planes will be different, so their success will require lots of investment and government collaboration if it’s ever going to take off.
NATE: A Virginia 17-year-old created a prosthetic arm controlled by your brain that costs just a few hundred dollars to make. The limb doesn’t require any invasive surgery, moves by reading your brain waves, and could be a boon for the more than 2 million Americans living with amputated limbs.