Today we talk about how crystallizing human urine can help save seagrass, a new AI program that can detect early signs of heart disease, and how mosquitos can be used to vaccinate against malaria.
Today we talk about how crystallizing human urine can help save seagrass, a new AI program that can detect early signs of heart disease, and how mosquitos can be used to vaccinate against malaria.
Pee and Seagrass
Heart Sound Maps
Modified Mosquitos
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Find episode transcripts here: https://curiosity-daily-4e53644e.simplecast.com/episodes/pee-and-seagrass-heart-sound-maps-modified-mosquitos
[SFX: INTRO MUSIC/WHOOSH]
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 crystallizing human urine can help save seagrass, a new AI program that can detect early signs of heart disease, and how mosquitoes can be used to vaccinate against malaria!
CALLI: Without further ado, let’s satisfy some curiosity!
[SFX: WHOOSH]
NATE: Calli, I just found out we’re going to be able to save the world with something you’ve just been throwing down the drain. Today’s story is about the benefits of, wait for it… human pee.
CALLI: Wow. Ugh. There’s a lot to unpack there, but tell me more.
NATE: Let me backup a bit. We talk a lot about different plants and animals that are in decline due to climate change and human impact, but I don’t think we’ve ever discussed something that can actually benefit from human waste. There’s some great work being done at the University of Florida on the decline of seagrass, which is an essential part of our ecosystems, and how human waste can help find a solution. Simply replanting the seagrass isn’t working because it has trouble surviving and growing at its regular speed due to the effects of climate change, especially in places with low nutrients in the water, like Florida.
CALLI: Okay, and how can our pee help increase those numbers?
NATE: Well, researcher Patrick Inglett and his colleagues figured out a way to take human urine and turn it into superfood for seagrass. There’s a compound called struvite that’s formed from human wastewater when the waste becomes sludge in a low-oxygen environment. Struvite is also super high in nutrients and is slow to dissolve.
CALLI: I’m assuming these are the exact nutrients seagrass needs to survive then?
NATE: Precisely. They also realized that the seagrass needed a powerful fertilizer to help with growth.
CALLI: So how did they conduct the experiment?
NATE: First, they filled large aquariums with shoal grass, which is one of the most common kinds of seagrass in the southern US. Then they used struvite in some tanks, and synthetic fertilizers in others. After sixty days, Inglett noticed a huge difference. We’re talking about five times more seagrass shoots in the aquariums treated with struvite and way less nutrients that dissolved into the water. And this is a major takeaway here because it really comes down to the difference in how struvite and the synthetic fertilizer dissolves.
CALLI: Wait, what does that mean?
NATE: Less pollution. Basically, seagrass needs a fertilizer that doesn’t also feed its competition for nutrients and sunlight: algae. As most fertilizer dissolves, it feeds algae that can expand and shade growing seagrass from the sun - slowing down its growth. When the algae uses up all the nutrients, it dies and decomposes which takes away a lot of oxygen in the water that the seagrass needs. This didn’t happen nearly as often with the struvite because it dissolves slowly and algae doesn’t like it as much.
CALLI: That’s so interesting. So, something about crystalized human urine makes it slower to dissolve and gives seagrass a better chance to grow?
NATE: Exactly! And Inglett says there are great long-term benefits for a slow-release fertilizer like this. Unlike normal fertilizers that provide just one pulse of nutrients, struvite will continue to nourish seagrass over time. It’s similar to if you were to take a slow-release medication.
CALLI: This sounds great. So - climate change solved?
NATE: Well… this is a potential fix for the seagrass issue in areas like Florida. We can’t be sure how struvite would work in the cloudier, more temperate environments of places like the northeast Pacific or Chesapeake Bay. In those areas, seagrass growth is actually limited by light instead of nutrients. So basically, nutrients provided from struvite would still be necessary but they don’t solve the issue raised from a lack of natural sunlight.
CALLI: Well, at least struvite is good for other areas right?
NATE: Yep. Inglett says that the question of supply is actually the biggest problem his study faces now. Because even though struvite has been a waste product for many years, it was only recently that some water plants started extracting the crystal on purpose to sell as an organic fertilizer. In certain parts of Europe, recycling struvite is encouraged as a means to reduce wastewater pollution. But in most of the world, struvite barely even exists.
CALLI: Let’s just say that struvite manages to catch on with the rest of the world. What next?
NATE: Long story short: there’s a good chance that within a few years, your pee might not just be waste. It will be an essential ingredient in saving the planet’s ecosystem.
CALLI: I guess we should all be making sure that we get our 6-8 glasses of water everyday. Flush for the planet!
NATE: Exactly.
[SFX: WHOOSH]
CALLI: So, I was listening to music on shuffle at the gym earlier when a band came on called The Heartsounds. Ever heard them, Nate? They’re pretty good! But their name reminded me of a recent study I read about how there’s a new way to diagnose diseases by mapping, get this… HEART SOUNDS.
NATE: Beautiful segue, Calli. That sounds a bit complicated, though. How does it work?
CALLI: It all started with a look into something called “aortic valve stenosis” which is one of the most common heart valve conditions. It’s present in about 5% of Americans over the age of 65 which is scary because it can lead to heart failure. Aortic valve stenosis is what happens when the aortic valve in our chests narrows, constricting blood flow from the heart though the entire body. So it’s common and dangerous AND, unfortunately, pretty hard to diagnose.
NATE: Why’s that?
CALLI: It requires sophisticated technology that lots of places around the world simply don’t have. Fortunately, researchers from the University of Kerala, India, and the University of Nova Gorica, Slovenia, have us covered. They developed a method to identify valve dysfunction that is accurate, simple to use, and low-cost for places that don’t have access to more expensive options.
NATE: How simple are we talking?
CALLI: This new method only requires a stethoscope and a computer and only takes ten minutes!
NATE: That’s awesome! How does it work?
CALLI: It reads heart sounds. Specifically, it reads for the sounds a heart should make. When the heart is healthy, it goes “LUB,” and that means it’s closing the mitral and tricuspid valves. Then it pauses, which is when the blood fills in. Then comes the second noise: “DUB.” This is when the aortic and pulmonary valves close. LUB DUB. LUB DUB. A lot is happening in between those heart beats.
NATE: What if my heart goes “wubba lubba dub dub,” Calli?
CALLI: Then I’d say you’re watching way too much Rick & Morty, now streaming on HBO Max, Nate. But anyway, the research team used data gathered from heart sounds collected over ten minutes to create a graph of how all the beats connect.
NATE: And what did they find?
CALLI: One of the researchers puts it bluntly: "In the case of aortic stenosis, there is no separation between the lub and dub sound signals.” They used machine learning to then examine the graphs to identify who had the disease and who didn’t.
NATE: How effective was that?
CALLI: They classified the disease accurately one hundred percent of the time. And this technology is also readily available in the US!
NATE: That’s incredible! Do you know how many people have already been diagnosed?
CALLI: Okay, so, about that… the method, so far, has only been tested with existing data, not in a clinical setting with live patients. But they firmly believe that the tests will continue to showcase the same results. Currently, the researchers are in the process of developing an app for mobile phones that can be accessed worldwide to measure your heart sounds. They also think this could be used to diagnose other conditions.
NATE: Like what?
CALLI: I mean, it can measure any type of heart sound signals, but it’s not a stretch to say it could also measure lung sounds and cough sounds as well. This would actually create potential for early diagnosis in, honestly, COUNTLESS diseases.
NATE: Last question: can this method be used to measure how good the band The Heartsounds are?
CALLI: No way, Nate. Only I can do that, and my verdict is that they rock.
[SFX: WHOOSH]
NATE: So, I don’t think it’s controversial to say that I hate mosquitos. I don’t know a single person who is pro-mosquito. They are one of the deadliest animals on the planet, causing diseases like West Nile disease, dengue fever, and yellow fever. BUT - what if I told you that mosquitoes could actually be the cure to one of the most common diseases they cause?
CALLI: Ooh! Which disease?
NATE: Malaria. And wait, I get it, you’re thinking “don’t mosquitoes carry malaria?” And the answer is yes, sometimes. Mosquitos are the cause for roughly 600,000 of malaria deaths per year, but new research from Dr. Sean Murphy at the University of Washington shows that the problem may also be the solution due to a little something called plasmodium parasites.
CALLI: What are plasmodium parasites?
NATE: They are parasites that technically contain malaria but they won’t activate malaria symptoms when they enter the body.
CALLI: Like a vaccine?
NATE: EXACTLY like a vaccine! Once the body identifies the parasites and the malaria they carry, it can build up the right antibodies to fight the malaria. So what the researchers did is that they literally filled up a box with mosquitos that were genetically modified with the plasmodium parasites and then had someone stick their arm in.
CALLI: Personally, that sounds like torture.
NATE: Oh yeah, it can’t have been fun.
CALLI: So, why use mosquitos? Was there another option for administering the parasite?
NATE: The researchers said mosquitoes are a cost effective way to conduct the experiment, describing them as “1,000 small flying syringes.”
CALLI: But they’re not proposing selling big boxes of mosquitoes at pharmacies to treat malaria, right?
NATE: Haha, not exactly. Mosquitos have been used in clinical trials before but it’s uncommon. Mosquitoes are obviously tiny so there needs to be a ton of bites. That being said, the results of this experiment are super promising, with one researcher even calling this a “game changer.”
CALLI: The box of mosquitoes or the neutralizing parasite?
NATE: In my opinion, both. In the opinion of scientists looking at this from a distance, the parasite. They performed this trial on 26 participants and found that the genetically modified parasites protected some participants from a malaria infection for a few months.
CALLI: Hmmm. Is that good?
NATE: To put it into perspective, RTS,S which is the world’s first malaria vaccine, not mosquito-based but, you know, a traditional vaccine, only has around a 50% success rate currently. The mosquitos are still a work in progress but researchers believe that in time, it will be far more successful than the RTS,S vaccine.
CALLI: That sounds pretty good and I’m sure it will be incredibly helpful to countries where malaria is a big issue.
NATE: You’re right on the money. Malaria isn’t a huge problem in the United States. But it’s very common in places like Africa, where four countries alone account for nearly half of the world’s malaria deaths yearly.
CALLI: So if the research is that promising, what would a vaccine like this cost in the future?
NATE: That’s still being determined. The researchers are partnering up with a small company called Sanaria to make the modified parasites, but increasing production to scale up manufacturing will require more investment. The short answer? It probably won’t be cheap.
CALLI: Could we not just give everybody a box of mosquitos so they can vaccinate themselves?
NATE: Well we’ve talked before about how mosquitoes are actually really useful as natural predators of other harmful insects, and the amount of mosquitoes that would have to die to give everyone a box of mosquitoes would probably wipe out the mosquito population almost immediately.
CALLI: You’re right, Nate. And it’s probably for the best since I… well, I don’t want to stick my hand into a box of mosquitoes.
[SFX: WHOOSH]
NATE: Let’s recap what we learned today to wrap up. Turns out pee isn’t just waste, a recent study out of Florida reveals that the emptied contents of your bladder can be crystalized into a compound called struvite that is capable of saving dying ecosystems. Struvite is a game-changing fertilizer for seagrass, which is dying all over the world. Someday soon, your pee might be an essential ingredient for saving the world!
CALLI: Through a new graphing technique, a team of researchers have developed a new way to accurately diagnose heart conditions earlier than previously possible. The best part is - it can potentially be used to help diagnose COUNTLESS other diseases!
NATE: Would you stick your hand into a box full of mosquitoes to prevent malaria? That’s what the subjects of a recent experimental trial did, who discovered a new and effective way to vaccinate against malaria. Thankfully, the final version of the trial will switch to more traditional needles, but for the time being, malaria is being fought directly by its most prominent spreaders!