WENDY: Hi, I'm Wendy Zukerman and you're listening to Science Vs from Gimlet. Today on the show - we are doing something a little different. The team at Science Vs is telling tales that push life to the ultimate limit.
Dudududud
We've got stories of bringing things back from the dead… we're diving into the mysteries of immortality… and asking just how much the human body can take??
Dudududud
And our first story starts, like many do, with a love story. I'm gonna tell you this story with our producer Meryl Horn.
MERYL: The guy who fell in love is Rohan Schoeman, he's from South Africa… He's an English teacher -- and several years ago… he met Audrey Mash. They ran in the same music scene… went to drum and bass nights together.
WZ One thing led to another…. They got married. And he just loved how adventurous she was.
RS: She brought that out in me. All sorts of stuff that I did that I do now that I wouldn’t have liked - like scuba diving and hiking.
MERYL: And it was all going great, until one trip - a few years ago. It was November. They were living in Barcelona and decided to do some hiking up in the Pyrenees mountains. It was in this remote spot- it took about a day to hike in. But it ended up being kind of a bust. It was drizzly and windy the whole time. So, they were looking forward to getting home.
RS: My feeling was okay let's get it done, we can go home like have a cup of coffee or something, just sit down yknow and be cozy.
MERYL: But that’s not what happened. So they'd been hiking for a few hours…
RS: We were more than halfway. It started snowing gently, lightly, like in a christmas movie, ya know- ah look there's snow softly coming down.
MERYL: The snow was a surprise. They checked the weather that morning and it was supposed to rain. So Audrey wasn't dressed for it at all.
RS: We stopped and we thought should we go forward, should we go back, and we decided let’s just keep going. We've walked most of the way… and then suddenly it got to the point where everything was just white.
MH Pretty quickly they were in a complete blizzard. They couldn’t see the path. And their cell phones had lost reception… it was getting really bad.
RS: The snow was deep, the sky had sort of whited out, so there was no horizon at this point, we couldn't see anything. There was nowhere to go. I'd never seen anything like it before in real life. We were getting really, really cold, both of us, I could feel a layer of snow, had gone into my pants, so between my skin and my pants, there was a layer of snow, we were both shivering, teeth clattering,
MH They crouched down - next to this rock for shelter. And the wind was so loud, that Rohan and Audrey couldn’t hear each other talk, so they stopped trying to talk to each other and just waited in silence... And it was then Rohan was like we might not make it out at all.
RS: This is going to be it. We are going to freeze to death, and people are going to find our bodies, when the storm has passed.
MH: Were you holding each other?
RS: Yeah we were like- that’s how I thought they were going to find us.
MH: Oh my gosh.
After a couple of hours of this-- the snow finally stops… and so they start making their way back home.
RS: And that’s when I thought ok we’ve-- this has been really terrifying, but we’ve made it. I was quite euphoric at this point, I thought wow we’ve made it. I turned around to tell her and she seemed weird. She seemed like she was drunk, she had trouble forming words, like her eyes were all over the place. So I tried to sit her still and then she looked really panicked, and then her eyes were rolling around and then she lost consciousness. I thought that she had died because it was literally her going like ‘Ahhh.’
Rohan thought he had watched his wife just take her last breath. He laid Audrey down and covered her with his jacket.
RS: I was hoping that I was wrong, but I thought that she was dead. I couldn't feel a pulse
<<PAUSE…>>
WZ: At some point, Rohan realized that his cell phone had reception again. He made some calls and found out that a helicopter was already searching for them. Audrey was ultimately flown to a hospital in Barcelona. Her heart had stopped working -- and she hadn't had a pulse in hours. Which means in all that time… her body and brain weren’t getting enough oxygen.
RS: I was a total mess- I was sobbing, I was not in a good place as you can imagine. //
I was thinking yknow funeral arrangements or, or what- … what she was going to be like if she did wake up- I just started thinking... like... I was like... how are the cats going to be when I get home, are they going to be upset that she’s not with me?
MH: ohhh
WZ: When Audrey got to the hospital -- Dr. Eduard Argudo was there to treat her. She was still in cardiac arrest
EA: And she was arrested for more than 2 hours - without any sign of life or any kind of electric activity in her heart.[1]
WZ: But Eduard had read about cases like Audrey’s - cases of people who had hypothermia - whose hearts had stopped- and yet, they still survived. So he figured, maybe I can bring her back.
EA: I really don't know if we're going to be successful or not - but if there's any chance, we should try it?
WZ: Audrey’s body was only 20 degrees celsius[2] - that's 68 fahrenheit… That’s really cold... and Eduard needed to warm her up -- to a normal body temperature and get oxygen to her organs fast.[3]
So to do that Eduard hooks Audrey up to a machine… an ECMO machine.. that takes the blood out of her body, warms it up, adds in some oxygen, and then pumps it back through her body.[4] But when Rohan saw Audrey like this - he said it was pretty disturbing.
RS: I mean it was quite, like, horrific, she was in her hospital bed, there were pipes going in and more pipes going out. She was one with the machines around her
MH: Wow, like the borg? Or something...
RS: Yeah exactly
MERYL: So as warm, oxygenated blood starts flowing through her body… Eduard can see that she's trying to breathe…
EA She started gasping,[5] that was a good signal… that means that the brain is not totally dead…
MERYL: After three hours the doctors check her pupils… and see that they're responsive[6]… which is another good sign and then, using a defibrillator… they give her heart a little jolt… and[7]
MH: what was that moment like that you saw that her heart was beating again?
EA: This was incredible. we just tried, it was a great moment.
MERYL: A couple of days later[8] -- Audrey wakes up… and Rohan couldn't believe it
RS: She knew her own name, she know who I was … she knew her parents… the fact that she was speaking that she was opening her eyes was better than I thought it might be
AS: I think I was on a lot of drugs when I first woke up. I just remember there being people there and seeing my family-and I remember thinking if everyone is here, it was really serious but i was in a blurry bubble
MH Haha yeah
MERYL: After only around two weeks in the hospital Audrey went home[9]. And just a few months after that-- she was training for a marathon.
AM I'm 100% fine, to have come out of it without any side effects at all. I do feel incredibly lucky
WZ: Ok, so how is any of this possible? How can someone still be alive after not having a heartbeat for hours? Well, her body had gone into a kind of hibernation.[10] Something special that happens when someone’s body gets cold…
EA Because when you decrease your temperature, your metabolism also decreases. And then your brain needs less oxygen and less blood flow to be alive.[11][12]
WZ: So normally, if your heart stops, organs, like your brain, don't get enough oxygen, and you can die.[13] . But in this case, because your metabolism slows down, your organs don't need as much oxygen[14][15][16] and you can survive. Which is why there’s this saying in medicine:
EA We say you’re not dead until you’re warm and dead.[17]
WZ: You’re not dead until you’re warm and dead. That's because - just like Audrey - we know it's possible for people to come back to life once they're body temperature goes back to normal.[18]
MERYL: Doctors have known that this is a thing for several decades.[19][20][21] Not everyone is as lucky as Audrey - to recover completely. But, it's actually pretty common to survive this- if you get the right treatment.[22][23][24] Like, one academic told me that out of 96 cases he's looked at, over 90% of them survived[25]. Audrey says it’s sort of odd to be a part of this club -- especially because she doesn’t actually remember the day of the hike -- at all.
AS: In a strange way, it feels more like it happened to my family than to me, because I was never conscious at any point when my life was in danger. I got a lot of messages, at first after the accident, from people online who wanted answers to the great mysteries of the universe. And some people who were quite upset that I wasn't willing to share them who thought I was part of some grand conspiracy theory who could answer all the questions about what comes next.
MH: Like not that you didn’t remember but were holding back?
AM: I was holding back yeah haha- I’d seen the light and the angels and could have said everything if i wanted to.
RS: I got the date tattooed on my chest, maybe I’ll cover it up, she thinks it’s a bit grim.
AM: I was fairly unsure that was a good idea- wasn’t sure I wanted to see the date every time I saw my husband shirtless for the rest of our lives. Hahahaha. It bothers me less now though- I think I don’t really see it, he’s got quite a lot of chest hair, hides it quite well.
MERYL: And something Audrey and Rohan are still grappling with- is how to talk about what happened. Did Audrey die?
AM: I mean i don't know how else you could really describe it, I suppose it's a difference between death and irreversible death, but what is death if it's not that your heart stops and your lungs stop- I don’t know how else to describe it.
MH Do you think Audrey died?
RS Short answer is I guess? there was just some science that I wasn’t aware of that with air quotes could bring someone back from the dead
WENDY: After the break … more stories of bringing things back from the dead… and we'll meet a creature that defies death… again.. and again… and again…
<<PRE ROLL BREAK>>
WENDY: Welcome back. Our next story is about one of the most curious creatures on earth -- a little creature who refuses to die. And to tell us all about it is producer Rose Rimler.
RR: I’ve always been drawn to animals that don’t look or act like animals that are familiar to us… As a kid I could never get excited about horses… but I used to love to watch water striders skate on the surface of puddles….and I’ve never really grown out of this attraction to nature's weirdos….so ever since I heard about a death-defying little creature a few years back...I always wanted to find out more about it. So recently I called up Nando Boero, a professor at the University of Naples in Italy .[26] He’s a marine biologist.
FB: I like to go scuba diving, look at beautiful animals not pressing buttons on machines
Nando and I are kinda two peas in a pod, except that I’m too claustrophobic to scuba dive. But we both LOVE strange little sea creatures...like jellyfish. The one we’re talking about today is a little, shallow-water species-- kinda looks like a floating light bulb with wispy tentacles[27], only it’s about the size of a lentil[28].
FB: whose name is turritopsis[29]
And Turritopsis does this amazing thing - that was discovered by total accident. It was 1988[30], and some of Nando’s graduate students went snorkeling near the marine lab off the coast of Genoa, Italy[31]. They collected some Turritopsis jellies. And they thought it might be fun to keep them in an aquarium in the lab. So they brought them back...
FB: they put the jellyfish in separate jars but they forgot about them
FB: because they are young people, they had girlfriends, whatever, so they didn't care much about nursing the tiny jellyfish
Because the students were too busy playing Pacman with their girlfriends or whatever the young people were up to back then, the tiny jellyfish went without food for a day or so... which meant they were starving. When the students finally remembered to check on them, they expected them to be dead[32]. But that’s not what happened. They weren’t dead. Instead they had vanished.
FB: When they came back the jellyfish were gone but there was a tiny polyp on the bottom of the jar,
A tiny polyp - it looks a bit like a blob of ear wax - and for the purposes of this story - we're going to refer to it as a young jellyfish. Which is maybe not technically correct - because the polyp is just a really different life stage for this creature. But if you wanna anthropomorphize jellyfish -- and I do -- it's an ok way to think about. Nando has a helpful analogy. He says think about it like….
FB: like a butterfly and a caterpillar, if you look at caterpillar it's very different from a butterfly, but it's exactly the same animal[33]
So this jelly went from mature adult-- butterfly-- back to polyp-- caterpillar. But of course, that's weird right? That is going the wrong way!!![34][35][36]
FB: So it’s like having a butterfly instead of dying goes back to a caterpillar stage. Turritopsis is breaking the laws, so it is doing something strange
So strange they could hardly believe their eyes. They couldn’t think of any reasonable explanation.[37][38] So, Nando and students recreated this-- they got more jellies, brought them back to the lab, didn’t feed them, and the same thing happened again!
These guys went back to polyps
Butterfly...to caterpillar...[39].
FB It was an amazing thing
Scientists who study jellyfish are used to some weird stuff[40]...[41]. But nobody had ever seen an animal cheat death by turning itself young again. That was new[42][43]. And people were like, if it does this over and over, then maybe this means the jellyfish could live forever - like maybe it’s immortal[44]! And so that’s what people started calling it-- the immortal jellyfish.[45][46][47][48]
FB: And the press became crazy about that. And journalists are still asking questions about the immortal jellyfish
RR: Hahaha. Like me!
FB: Haha exactly, like you
But could this animal really keep pulling this trick forever --restarting its life again and again? in other words is it really immortal??? Or is this just...clickbait?
RR: Do we know how many times the same animal can go from polyp to jelly… to polyp to jelly?
FB: There's a crazy guy in Japan, Shin Kubota. If you approach him he will tell you.
RR: I’m trying to figure out… I got a notice that Shin is in the meeting… Oh!
SK: Good morning!
RR: Good morning!
RR: Shin Kubota speaking
This is that guy in Japan. He’s also a marine biologist[49]… I thought I was obsessed with this little jelly but Shin takes it to another level -- he wrote this song about it!!!
<<song comes up[50]>>
At one point in the song he sings from the perspective of an old jellyfish… and says "I’ll be able to revert to a polyp soon… I’m going back to the strapping body
Hatachi-no pichi-pichi na karada ni
I had when I was 20—1, 2, 3.
Ima kara modoru zo 1, 2, 3
I’ll be able to start my life over again.
And I think if Shin could rejuvenate, he would spend another lifetime studying jellyfish.
SK Hahaha
In Japanese: It'd be wonderful if we could rejuvenate like the jellyfish
Scientists are still working out how these jellies can cheat death... but it looks like their cells can kind of reprogram themselves ... they can basically switch from being a muscle cell, for example, to some other kind of cell. In the process-- and this is what’s really weird about Turritopsis-- the whole animal just sort of dissolves…. it curls up on itself… and becomes a little lump. Or what Shin calls… a--[51]
SK Meatball
A meatball. And then it grows up again…. So… how many times can they do this? Have we found a cut-off point? Or are they really immortal?
Well for years Shin has been keeping these jellies in a lab.[52][53] Feeding them teensy shrimp, sometimes by hand.[54][55][56]
SK It’s quite tough work, laugh
And over the years Shin has watched as the jellies, got older… and then younger… butterfly to caterpillar… and back again. Sometimes Shin would sort of kick-start the cycle… by stressing them out. While Nando’s students did this by starving them, Shin often did this by pricking them with a needle or even crushing them.[57][58]
SK Japanese: the objective is to hurt them by stabbing/poking or even crushing...
RR: He says, sometimes he feels bad for the little jellies... but whenever he does this...he sends out a wish that this will turn out for the best-- he asks ‘please rejuvenate.’ Also he’s pretty sure they don’t feel pain.
Itami wo kanji nainode, daijobu desu: They can't feel pain, so it's okay.
So for years Shin watched and stabbed...and counted...and saw the jellies rejuvenate… once… twice… three times… kept going…
SK ten times
...11...12...13...14…and then…in 2015… a huge typhoon hit Japan[59]….
<<wind/rain sounds>>
<<Typhoon Nangka has reached Japan>>
<<Authorities urge 350,000 people to evacuate their homes>>
The typhoon caused lots of destruction but for the jellies, the problem was-- Shin was using ocean water in their tanks - but with the rain from the typhoon the ocean water was now way less salty than usual…. [60] And this kind of stress… this was too much for the jellies. They couldn't rejuvenate their way out of it. And they died.
"Wakagaeru nouryoku wo motte eien ni ikitsuzukeru...."they have the ability to rejuvenate and live forever.. but they're fragile, and live a paradoxical life
Because… here’s the thing about the immortal jellyfish… while it can do this amazing trick… it’s not invincible. They’re actually kind of fragile.
SK: Difficult to grow;
Which I find really confusing… How they can be fragile AND immortal? Why would one catastrophe, like getting stabbed, inspire them to rejuvenate, and another catastrophe like a typhoon just straight up kill them?
SK: *laugh* Yes very very contrasting
Shin's best explanation is that this rejuvenation thing is a trick they have up their sleeves… sometimes they can pull it out and live another day… but sometimes it’s too much for them… and they really do die.
But there’s still the possibility… that with the perfect conditions… maybe they could keep rejuvenating forever? There’s some debate here... But Shin has a lot of faith in these little creatures.
RR: Do you think that it's possible for it to… for one animal to regenerate even more times, 20 time, 50 times, a 100 times? Is there a limit?
SK: Unlimited.
RR: Unlimited?
SK: Forever, forever, I think, yes, haha
It's nice to imagine. This light bulb creature...drifting around off the coast of Japan, cycling back and forth, for thousands.. thousands of years… maybe?
WENDY: For our third story today, we’re going from the tiniest light bulbs to massive balls of gas - we’re talking about stars! And we’re about to hear the tale of a star that can claw its way back from the brink of death. And to tell us all about it is Michelle Dang, a producer at Science Vs.
MD: So some stars can live for billions and billions of years,[61] but they all have to die eventually.[62] And the type of stars we are talking about today -- essentially die when they run out of fuel and can’t blaze anymore... They start dimming and become what’s called a white dwarf. [63][64][65][66]
But a white dwarf doesn’t always go gentle into that good night --- sometimes it can hold onto its shine by literally feeding off another star.[67] Becoming what astrophysicist Moiya McTier[68] - would call --
MM: Vampire stars, which I love -- cause it really is like a vampire just sucking out the life force of the other star
Here’s how it works. So, say you’re a white dwarf star that’s about to die … you're on your last star legs. But nearby! You’ve got a star neighbor -- a big flaming red giant that’s throwing around all this hot gas[69] .. we’ve all got a neighbor like that
MM Red giants are shedding materials from their outer layers, so they're sending out mass into space between stars[70]
And if this red giant is at the right distance… at the right time[71]… then you the white dwarf star can basically start sucking up all the gas that’s being thrown at you….
MM: So you get these discs of material around the white dwarf.[72] So it's almost like the white dwarf is eating the material from its larger companion[73]
And once you’ve got that gas -- boom -- you can start shining bright like a diamond again.[74]
MM: Which is, I think, very exciting
Sometimes these white dwarfs even pick up so much gas that they they have these crazy looking outbursts[75] that look like this ---
MM: These big powerful jets that shoot off-- and they look like big columns of light, big columns of energetic material being shot off from these stars.[76]
The sciency term for this is ‘symbiotic stars’...but it’s a lot more fun to think of them as… back-from-the-dead stars. Or as Moiya puts it:
MM: I would call them undead? Hah. I think that these white dwarfs are more like vampires or zombies in that they aren’t totally alive. But they’re active again-- they’re moving![77]
MD: Yea, I love that too-- vampire zombie stars
MM: Zombie stars, yeah
And for some, this process of sucking the gas from their neighbour -- can help keep the vampire zombie star stay ‘alive’ - in a way, for hundreds of thousands of years.[78]
MM: And that’s what makes them special
WENDY: After the break -- our final story: a 3000 year old Egyptian mummy… sings from its grave..!!
BREAK
WENDY: Welcome back! Our final story for today -- The Mummy Returns.
Ok so, several years ago some boffins from England had a rather bonkers idea: to bring back the voice of someone who died 3,000 years ago. One of those men was Professor David Howard[79], a musician and engineer[80] - at the University of London who studies voice… And he has all these devices to help him …
DH: So- what I've got here--this, is a buzzing device
During our interview.. he whipped one out.
WZ: Can you just say, can you just say- Luke I am your father
DH: Luke I am your father
WZ: Ahahaahha
DH: I hope that’s made your day
WZ: Haha It has!
Several years ago… David even created an organ using his own voice[81]
<<Organ music>>[82]
DH: And I suppose I was looking for another outlet
And one day he sat down for coffee with a friend, who's an archeologist, who gave him a curious proposal.
DH: This was one of those sort of- have a cup of coffee and chat about something slightly off the wall about whether we could do anything with the voices of human remains
David’s colleague was asking him: do you reckon we could bring back the voice of someone who was long gone?... like ...long gone? And they had the perfect guy for the job.
DH: Well he’s… he’s 3000 years old and he has been mummified.
Yeah, they ultimately wanted to bring back the voice of an ancient egyptian mummy. And if they could do this -- it would be the first time in history that someone would recreate the voice of such an ancient human.[83] The mummy's name is Nesyamun.[84] Historians think he was a high-ranking priest living in Egypt some 3000 years ago.[85] And David says he had a very sweet gig at the temple -- every morning -- he would place the best beef on the altar...[86][87]
DH: So he would be given a fillet steak and he would go through a door, put this on the altar, and go about his business during the day, and any remaining steak that god had not taken, only Nesyamun could eat. So my understanding is that he basically lived his life on fillet steak on a daily basis[88]
WZ: Haha- and I guess it depends on how hungry god was, you know
DH: I guess it does
Nesyamun lived into his mid-50s.[89] He was mummified , placed in a wooden coffin painted with hieroglyphics, and laid to rest in Egypt.[90][91] But his resting place was pillaged by tomb raiders… and he was brought over to Europe[92] and ultimately went on display in a British town called Leeds in 1823.[93] And that’s where he is today, at the Leeds Museum.
And once David and his mate had this idea of recreating this mummy's voice… The two were on a mission. They talked the Leeds Museum into lending them their mummy -- the museum heads figured hey! Hearing Nesyamun's voice might breathe new life into a dusty exhibit about a guy who ate too much beef 3 thousands years ago.
So now… it's go time. To bring back Nesyamun's voice -- David needs a copy of this mummy’s vocal tract.[94][95][96][97][98][99][100]
So the vocal tract is basically a tube that starts at your lips and ends just above your lungs. And in a living person - as the lungs push air out -- it vibrates these two muscley flaps— our vocal cords. When the vocal cords vibrate faster or slower, that alters the pitch— making a higher or lower noise.[101]
And so what David wants to do -- is to get Nessyamun's vocal tract. But David wasn't about to unwrap the mummy and rip out his throat. So instead - David needs to make a 3D model… by first scanning the vocal tract in this very non-invasive way-- using a CT scanner at a local hospital. The mummy handlers did it in the middle of the night - so they wouldn't freak out actual patients at the hospital.
DH: They were very conscious that they didn't want people wondering what on Earth was going on here-- cause it would have looked very strange. And it just looked as if we were ordinary people- waiting, and then suddenly the door opened and this trolley came in--and there he was.
Nesyamun was carefully hoisted out of his blue and gold coffin[102] and slid into the machine... David could see his toes poking out. The scan starts, with its whirring and buzzing.[103][104]... And then-- it works! David gets this beautiful, clear scan of Nesyamun's vocal tract.
DH: Um I mean, this is going to sound morbid but it's true- the difficulty of putting live people in is they have to breathe- and if they breathe, their flesh moves.[105] So if you've got somebody who does not move, the pictures are really clear-- the edges are really clear. And that, that was fantastic.
With the scan in hand, David goes to step two: he prints out a 3D model of Nesyamun’s vocal tract. It’s printed out of a thin, white resin.[106] He showed it to me. It was a little bit hard to describe … but I gave it a go...
WZ: Ooooh you know what it looks- it looks a bit like um… it looks as if a mouth has like sort of come out of a genie's lamp and gone ‘aerrrrrrruuuh’
DH: Oh I see… ha yea well it’s… yea…
Hurumph, maybe just imagine a smaller, lumpy upside down saxophone.[107] From here - David attaches a loudspeaker to the bottom of the model[108][109] and when he turns it on… it sends vibrations through the freshly printed vocal tract[110][111]… And now, we can finally hear what Nesyamun’s voice might have sounded like 3000 years ago. Here it is:
<<Nesyamun sound>>[112]
DH: So it's somewhere around an Eh vowel. I think it's Eh and Ah[113][114]
WZ: perhaps imagine he's just waking up, 3000 years ago and just ‘eeuuuuh’
DH: Ye-ahahahaha yea--why not. Why not indeed
WZ: So he makes this ‘eeeeeuhh’
DH: That's very good, that's very good- are you auditioning to take his role?
WZ: Ahaha!
Arright so talking involves your tongue and face muscles moving about[115][116]… which they couldn't get Nesaymun to do to... so that's why he's not reciting a soliloquy.[117][118] Still though…
WZ: So did you bring his voice back from the dead?
DH: Well, our argument is that we did- yes-- in some sense… this is his afterlife and we have created a sound from his remains... and there was that sense of awe- and wonder- the fact that this voice can be recreated. It was a very special moment.
<<Nesyamun sound>>[119]
And here's what’s eerie about all this. It's almost as if Nesyamun knew that this might happen… because of something scribed in the hieroglyphics on his coffin...
DH: What's written in his coffin is the phrase- “True of Voice” and, um, it is understood from I believe writing around the time that he reckoned that his voice would be heard in the afterlife[120]...
And David is now taking this prophecy to a whole new level… he’s been working out a way to get Nesyamun to sing in a choir…. kind of... David changed the way that the air was vibrating through the Mummy's vocal tract -- changing the pitch of Nesyamun's voice, so that he "sang" all these different notes… and here he is singing Handel.
<<Let’s see if this works…. Ok! So I can add vibrato *note* …. >>
<<Music playing >>
That's Science Vs.
Hello producer Rose Rimler
Hello host Wendy Zukerman
How many citations?
121!
Go to the transcript…
Instagram this week! There's a lot of cute photos -- my favourite is the jellyfish
Our instagram is Science_Vs
Also! Astrophysicist Moiya McTier - who told us about vampire stars - has a wonderful podcast called Exolore where she uses science to imagine life on other worlds…. Asking questions like if intelligent life evolved in the clouds of Venus...what would they be like? So check it out!! It's called EXOLORE.
This episode was produced by Meryl Horn, Rose Rimler, Michelle Dang, Nick DelRose, me Wendy Zukerman, with help from Taylor White. We’re edited by Blythe Terrell and Caitlin Kenney. Fact checking by Eva Dasher. Translation by Ben Milam, Kana Hatakeyama, and Bumi Hidaka. Mix and sound design by Bumi Hidaka. Music written by Bumi Hidaka, Peter Leonard, Bobby Lord, Marcus Bagala, Emma Munger and So Wylie. A special thanks to all the researchers we spoke to for this episode including Dr. Jordi Riera, Professor Lars J Bjertnæs, Dr. Peter Paal, Dr. Herman Brugger, Prof. Maria Pia Miglietta, and Dr. Jenna Valley. Plus a big thanks…Sinduja Srinivasan, Katie Cruickshankk, Jessica Mack, the Zukerman family and Joseph Lavelle Wilson.
I'm Wendy Zukerman - fact you next time.
[1] Full neurological recovery 6 h after cardiac arrest due to accidental hypothermia… [at the moment she arrived at the hospital] ...She arrived 2 h and 25 min after the first evaluation—she was still in asystole
[2] She arrived 2 h and 25 min after the first evaluation—...and had a core temperature of 20·2°C.
[3] Ventilation must be started as soon as ECLS [Extracorporeal life support] has been established to avoid perfusing the heart and the brain with deoxygenated blood
[4] Extracorporeal life support ECLS using veno-arterial extracorporeal membrane oxygenation (VA-ECMO) or cardiopulmonary bypass (CPB) are the rewarming treatments of choice
[5] Peripheral venoarterial extracorporeal membrane oxygenation (ECMO) support was started and a fine
ventricular fibrillation rhythm was immediately seen on an electrocardiogram (ECG). The patient also started gasping,
[6] once the woman was stable, her body temperature was progressively increased at a rate of 3°C per h. The patient regained pupillary reactivity after 3 h of extracorporeal support. When her temperature reached 30°C, coarse ventricular fibrillation was observed. -
[7] When her temperature reached 30°C, coarse ventricular fibrillation was observed...She was then
defibrillated, which resulted in a posterior effective rhythm—.
[8] ECMO was stopped after 45 h and 40 min. The patient was successfully extubated on day 2 of her stay in the ICU.
[9] She was allowed home on day 11. A month after the episode, she had resumed her normal activities of
daily living.
[10] Mammalian hibernation is an amazing strategy for winter survival. Animals sink into a deep torpor where metabolic rate is <5% of normal, body temperature falls to 0-5°C, and physiological functions are strongly suppressed.
[11] Hypothermia increases the tolerance of the brain to ischemia. It slows metabolic processes and reduces oxygen consumption.22,23 The protective effect of moderate hypothermia has been applied successfully in the treatment of traumatic brain injury.24 In cardiac surgery deep hypothermia is routinely used for cerebral protection when circulatory arrest is required.
[12] Hypothermia causes a reduction in cerebral demand for energy via temperature-dependent reduction in rates of biochemical reactions (Q10), as well as by lowering levels of the excitotoxic neurotransmitter glutamate.
[13] Cardiac arrest causes the cessation of cerebral blood flow, which produces loss of consciousness within 6 seconds [3]. If oxygen is restored immediately, consciousness can return in seconds to minutes. Two minutes of anoxia can cause focal damage. If the anoxia lasts longer than 4 minutes, brain cells begin to be lost permanently [4]. When ischemic anoxia lasts longer than 10 minutes most patients do not regain consciousness [5]. The pathophysiology of hypoxic-ischemic cell death is that, as neurons are deprived of oxygen, the proteins and electrolytes necessary to maintain the membrane potentials...
[14] Cooling of the human body decreases cellular oxygen consumption by about 6% per 1 °C decrease in core temperature.40 At 28 °C, oxygen consumption is reduced by approximately 50% and at 22 °C by approximately 75%. At 18 °C the brain can tolerate cardiac arrest for up to 10 times longer than at 37 °C. This results in hypothermia exerting a protective effect on the brain and heart,41 and intact neurological recovery may be possible even after prolonged cardiac arrest if deep hypothermia develops before asphyxia
[15] Survival chances are very low in buried avalanche victims with unwitnessed asystole at extrication [2, 4] because hypoxia has generally preceded CA leading to irreversible brain damage and death within minutes.
[16] Brain oxygen-consumption decreases by ~6 % per 1 °C fall in core temperature [8] and reaches 16 % at 15 °C [124] compared with normothermia. This improves the brain’s tolerance for low- or no blood-flow states. At 18 °C the brain tolerates CA for up to 10 times longer than at 37 °C
[17] “Nobody is dead until warm and dead” The clinical presentation of severe and profound accidental hypothermia is difficult to distinguish from clinical signs of death. The salvageable accidentally hypothermic patient could present without pulse, respiration and consciousness and with dilated non-reacting pupils and muscle rigidity. We have therefore advocated resuscitating and treating these patients aggressively regardless of clinical presentation, risking over-triage.
-reacting pupils and muscle rigidity. We have therefore advocated resuscitating and treating these patients aggressively regardless of clinical presentation...We thus uphold our credo during the last 28 years: “No victim of accidental hypothermia is dead until warm and dead”.
[18] This study evaluated the long-term outcome of survivors of accidental deep hypothermia with circulatory arrest who had been rewarmed with cardiopulmonary bypass.
[19] Patients presenting in cardiac arrest from accidental hypothermia may be rewarmed effectively using TL
[20]1979- An unconscious patient who is cold and rigid with fixed dilated pupils and undetectable pulse or respiration is worth resuscitation attempts if hypothermia is suspected.
[21]In 1967, a case with a regular alcohol drinker, weak pulse: A case of severe, chronic hypothermia (body temperature 21.4"C) was successfully treated by means of extracorporeal circulation containing heat-exchanger and oxygenator. Thoracotomy was avoided. As far as we know, this is the first patient to survive such a low temperature without any residual disability.
[22] https://www.sciencedirect.com/science/article/pii/S0300957214005243 Thirty-four patients were included in the study, 25 males (73.5%)and 9 females (26.5%). Nine patients survived (26.5%) while 25 died(73.5%)
[23] This clinical experience demonstrates that young, otherwise healthy people can survive accidental deep hypothermia with no or minimal cerebral impairment, even with prolonged circulatory arrest...In 32 of the 46 patients, rewarming with cardiopulmonary bypass was attempted, resulting in 15 long-term survivors. = 70%
[24] Analysis revealed a 67.7% survival to discharge and a 61.5% rate of good neurological recovery for patients presenting with pure hypothermic cardiac arrest.
[25] Email from [source] April 2021 “In an appendix to the article, included as supplementary material, we present 96 abbreviated cases of hypothermic cardiac arrest whereof 88 survived to hospital discharge.” Update May 17, 2021: this study is now published “Figure 5 summarizes 80 case reports with 96 victims of HCA, who underwent rewarming with ECLS. Thirty-nine patients were rewarmed with CPB (2, 15, 45–75) and 57 patients with ECMO (15, 76–123). Overall 88 patients survived (92%).”
[26] https://translate.google.com/translate?hl=en&sl=it&u=http://www.dipartimentodibiologia.unina.it/personale/ferdinando-boero/&prev=search&pto=aue
[28] See Bavestrello 92 paper. Fig 1. Drawing and scale bar-- the bell is about 1 mm, the tentacles another 2 mm. Nando agreed with "about the size of a lentil."
[29] The jellyfish Turritopsis dohrnii (Weismann, 1883) (Hydrozoa, Oceaniidae) was the first metazoan described with the ability to break this biological dogma by reversing its ontogeny under stressful conditions
[30] https://thebiologist.rsb.org.uk/biologist-features/everlasting-life-the-immortal-jellyfish#:~:text=One%20of%20the%20first%20researchers,organism%20really%20can%20live%20forever&text=As%20with%20so%20many%20findings,jellyfish'%20was%20discovered%20by%20accident.&text=Normally%2C%20in%20the%20hydrozoan%20life,then%20spawn%20sperm%20and%20eggs and pers. Comm with FB
[31] Some of these details are in Bavastrello 92 paper
[32] Pers. comm with FB
[33] Holometabolous insects undergo radical changes not just in body form, but also in life style, diet, and dependence on particular sensory modalities as they proceed through complete metamorphosis. Indeed, it is hard to believe that a cryptic caterpillar chewing on a leaf, or a maggot wriggling in decaying flesh, is in fact the same animal as the colorful butterfly or noisy blowfly emerging from the transitional pupal stage.
[34] The discovery of reverse development in T. dohrnii was the starting point for a considerable research effort on the cellular mechanisms underlying medusozoan reverse development
[35] Turritopsis dohrnii (Cnidaria, Hydrozoa, Hydroidolina, Anthoathecata) is the only known metazoan that is capable of reversing its life cycle via morph rejuvenation from the adult medusa stage to the juvenile polyp stage
[36] Typically, complete metamorphosis of insects (Figure 1) consists of four stages: egg, caterpillar, pupa (chrysalis), and adult butterfly.
[37] In a typical hydrozoan life cycle (Figure 1), adult, free-swimming medusae release gametes into the water column for external fertilization, producing short-living planktotrophic planula larvae with limited dispersal distance (Bouillon et al. 2006).
[38] The normal life cycle of hydrozoans involves the asexual budding of medusae from colonial polyps. Medusae of Turritopsis, however, when starved or damaged, are able to revert their life cycle, going back to the polyp stage through a process called transdifferentiation.
[39] Turritopsis dohrnii, also known as the immortal jellyfish, has a complete life cycle with fully developed medusa that optimizes the potential for long distance hitchhiking in ballast waters by biologically bypassing death caused by physical damage, environmental changes, and aging through the reversal of its life cycle (Bavestrello et al. 1992; Piraino et al. 1996; Piraino et al. 2004). Medusae of T. dohrnii exposed to unfavorable conditions are able to settle into a dormant, cyst-like cluster that metamorphoses back into a polyp, which then asexually propagates into a fertile colony in a suitable environment.
[40] Hydrozoan life cycles are among the most varied of the animal kingdom, with a vast array of different patterns
[41] When a hydra is bisected in the body column, the upper half will regenerate a foot at its basal end, whereas the lower half will regenerate a head at its apical end (Fig. 2A). This finding occurs when the animal is bisected anywhere along the upper 7/8ths of the body column. Similarly, when a piece of the body column is isolated, it will invariably regenerate a head at the apical end, and a basal disk, or foot, at the basal end
[42] This is the first metazoan known to revert to a colonial, juvenile morph after having achieved sexual maturity in a solitary stage.
[43] The observation was so revolutionary that it was presented at the second workshop of the Hydrozoan Society[1]. It was so revolutionary in fact that one of the attendees, the late Volker Schmid, expressed serious doubts about the report. He said it was impossible.
[44] A representative of hydrozoans, Turritopsis dohrnii, exhibits an exceptional ability to avoid death: when facing an injury, aging or unfavorable environment, its medusal form shrinks, loses its swimming skills, and undergoes a retrograde transformation to a chitin covered, poorly differentiated cyst, which eventually gives rise to a preceding juvenile morph, the polyp [40]. This specific metamorphosis, in a direction opposite to the typical ontogenetic path, caused T. dohrnii to gain a colloquial name—the immortal jellyfish
[45]Turritopsis dohrnii’s reverse development is considered a metamorphosis (Müller and Leitz 2002; Berking 1998), albeit in the opposite direction of its normal developmental trajectory and has earned T. dohrnii the popular appellation of “immortal jellyfish”.
[46]Turritopsis dohrnii, the so-called "immortal jellyfish," can hit the reset button and revert to an earlier developmental stage if it is injured or otherwise threatened.
[47] The supposedly 'immortal' jellyfish Turritopsis dohrnii has captivated scientists since it was discovered decades ago.
[48]A very specific jellyfish to be exact: the Turritopsis dohrnii, which is more commonly, and aptly, called the immortal jellyfish.
[51] Biological processes that occur at the cyst stage...involved in T. dohrnii’s reverse development and transdifferentiation….the ontogeny reversal of T. dohrnii involves cell transdifferentiation, a reprogramming of structural and functional commitment and gene expression of well-differentiated, somatic cells into other cell types either directly, or through a preparatory return to a state of poor differentiation (Okada 1991; Schmid 1992). ...Though transdifferentiation has been reported in T. dohrnii, the process of de-differentiation cannot be ruled out and may occur simultaneously with transdifferentiation during regenerative processes.
[54] , in the initial rejuvenated stage, 1/2 body of the newly hatched Artemia nauplius is sufficient for a zooid for a few days fed by hand using a pair of needles (a body part of Artemia nauplius touched to the mouth of the zooid by needles, then it can engulf by itself).
[55] For the last 15 years, Kubota has spent at least three hours a day caring for his brood. Having observed him over the course of a week, I can confirm that it is grueling, tedious work. When he arrives at his office, he removes each petri dish from the refrigerator, one at a time, and changes the water. Then he examines his specimens under a microscope. He wants to make sure that the medusas look healthy: that they are swimming gracefully; that their bells are unclouded; and that they are digesting their food. He feeds them artemia cysts — dried brine shrimp eggs harvested from the Great Salt Lake in Utah. Though the cysts are tiny, barely visible to the naked eye, they are often too large for a medusa to digest. In these cases Kubota, squinting through the microscope, must slice the egg into pieces with two fine-point needles, the way a father might slice his toddler’s hamburger into bite-size chunks. The work causes Kubota to growl and cluck his tongue.
“Eat by yourself!” he yells at one medusa. “You are not a baby!” Then he laughs heartily.
[56] It is a full-time job, caring for the immortal jellyfish. When traveling abroad for academic conferences, Kubota has had to carry the medusas with him in a portable cooler. (In recent years he has been invited to deliver lectures in Cape Town; Xiamen, China; Lawrence, Kan.; and Plymouth, England.) He also travels to Kyoto, when he is obligated to attend administrative meetings at the university, but he returns the same night, an eight-hour round trip, in order not to miss a feeding.
[57] “It is easily artificially to induce rejuvenation when the medusa body was stuck 50 or more times by a needle”
[58] when physically damaged, senescent, or faced with adverse environmental conditions, the medusae of T. dohrnii avoid death by reversing their life-cycle in the opposite developmental direction, i.e., transforming back into the post-larval, benthic polyp (Figure 1). During its reverse development, medusae shrink and lose their swimming competence, settle onto the substrate, and transform into a cyst-like stage characterized by a thin chitinous external envelope with no recognizable morphological features that can be ascribed to either medusa or polyp….In the following 24-36 hr, the cyst develops polyp-typical features, such as the stolonal hydrorhiza, where new polyps will arise from, eventually returning to the customary polyp-to-medusa ontogenetic sequence
[59] https://www.japantimes.co.jp/news/2015/07/17/national/typhoon-nangka-pounds-shikoku-pair-dead-hundreds-thousands-told-flee/#.VbZ9iflViko
[60] due to strong rainfall by an usual typhoon attacked to our region in middle of May, 2015, every cultured colony died (Kubota, 2015)
[61] This mass interval spans a huge range in stellar lifetimes, from the longest lived low-mass stars, that have existed for as long as our Galaxy (≈ 1.2 × 10^10 years) to the most massive of this range, whose lives are over in the blink of a cosmic eye (≲ 20 million years).
[62] An Introduction to Stellar Astrophysics (2011) A star can be defined as a self - gravitating celestial object in which there is, or there once was (in the case of dead stars), sustained thermonuclear fusion of hydrogen in their core. .. As time passes, the abundance of hydrogen gradually decreases in the star’s core, and eventually, the fuel for this particular nuclear process, namely hydrogen, will all be spent. … the outer regions of the star expand. The star then becomes what is called a red giant. The final destiny of a star depends almost solely on its initial mass; it will either become a white dwarf, a neutron star or a black hole.
[63] CSIRO: Typical luminosities are less than 10-3 that of our Sun. … As white dwarfs are so faint they are also hard to detect. We are only able to observe relatively close ones. (Also see the figure under ‘White Dwarfs.’ See the White Dwarf bubble - very hot (top axis) but lower luminosity (right axis).)
[64] See ‘WD’ in figure 1 here: Low Mass stars, Lower/Middle Intermediate (Stars that end up as White Dwarfs) -- (Symbiotic stars are de facto the low- and intermediate-mass interacting binaries)
[65] Berro & Oswalt 2016 White dwarfs are the final remnants of low- and intermediate-mass stars. Their evolution is essentially a cooling process that lasts for ∼ 10 Gyr.
[66] NASA: When the core of the former red giant has exhausted all of its fuel and shed all the gas it can, the remaining dense stellar cinder is called a white dwarf. The white dwarf is considered “dead” because atoms inside of it no longer fuse to give the star energy. But it still “shines” because it is so hot. Eventually, it will cool off and fade from view.
[67] Mikolajewska 2010: Symbiotic stars are interacting binaries involving an evolved giant … transferring mass to a hot and compact companion, usually white dwarf.
[69] Red giants naturally loose mass through a stellar wind
[70] Borro et al 2009 Mass loss is known to be a key factor in the late stages of the evolution of an AGB star. Matter escapes easily because of the low surface gravity. .. These stars become unstable to large amplitude radial pulsations and drive strong shock waves that produce an extended envelope and a copious stellar wind … The powerful stellar winds also affect the evolution of the interstellar medium by influencing its dynamics and spreading elements generated in stellar interiors.
[71] Mikolajewska 2010 The nature of the giant determines the orbital separation at which the symbiotic interaction occurs: the binary must have enough room for the red giant … and yet allow it to transfer sufficient mass to its companion. As a result, orbital periods for the S-types are of about 1–15 years
[72] Perets & Kenyon 2013 In wide binaries, the companion star captures some of the mass ejected in a wind by the primary star. The captured material forms an accretion disk
[73] Borro et al 2009 Mass accretion can be increased due to the gravitational attraction from the accretor and the centrifugal force due to the rotation of the system.
[74] Perets & Kenyon 2013 In these systems, accretion rates exceeding 10^−9 M⊙ yr^−1 yield bright UV sources which can ionize the wind from the primary (Kenyon & Webbink 1984). This ionized wind produces bright optical and UV emission lines (Kenyon & Webbink 1984) and a luminous radio sources at cm wavelengths (Taylor & Seaquist 1984).
[75] Perets & Kenyon 2013 Accreted material has a more significant impact on accreting white dwarfs. Aside from their visibility as symbiotic stars, wind-fed disks surrounding white dwarfs can produce a variety of eruptive phenomena (Kenyon 1986).
[76] Sokoloski 2003 Collimated outflows of material (“jets”) have been observed from at least 10 of roughly 200 known symbiotic stars … Most of these jets are transient, and seem to appear during or after an optical outburst, or temporary brightening. They then tend to fade on time scales of months to years.
[77] See 6.2 Burning Symbiotic Stars (nuclear burning happens at the surface/envelope of the WD; (and see previous cite An Introduction to Stellar Astrophysics (2011) -- WD no longer have enough hydrogen in cores to permit the level of fusion they did as main sequence stars, and they are not hot enough to fuse the heavier elements(e.g. carbon and oxygen) remaining in their core)
[78] Kenyon - The Symbiotic Stars (1986) Book. Pg 115 A unifying factor among symbiotic systems is the evolved red giant star losing mass via stellar wind or tidal overflow. This giant, whether it be a Mira, a semi-regular, or a non-variable red star, severely limits the length of the symbiotic relationship, as the evolutionary timescale for this star is < 10^6 yr; Pg 126 The white dwarf companion accretes some of this material, and provides a source of high energy photons which ionize the wind. Although these systems are formed less frequently than "first generation" symbiotic stars, they remain symbiotic for ~10^6 yr and make up ~50% of the entire symbiotic population. [MD: email with SK The lifetime of a symbiotic star is set by the lifetime of the red giant. Most red giants live about a million years - some might live for a few million years but none should live as long as 10 million years.]
[80] David is an organist at St. Mary's Thorpe, Musical Director of Feltham Choral Society and a choral singer. He links his musical interests in with his research whenever possible.
[81]This paper describes the use of 3-D printed models of the vocal tract for different vowels that are used to create an acoustic output when stimulated with an appropriate sound source in a new musical instrument: the Vocal Tract Organ.
[82] https://www.youtube.com/watch?v=svZNaiBIKMU
[83] The furthest we could get—which is incontestably a tour de force—was to CT-scan the mummified body of an Egyptian scribe and priest, Nesyamun, from about 3000 years ago, print a three-dimensional reconstruction of his vocal tract, and produce a creepy sounding [æ:::]
[84] The body is in an unusually perfect state of preservation.
[85] Experts believe that Nesyamun was a high-ranking Egyptian priest, incense-bearer and scribe at the temple of Amun in Thebes’s Karnak complex.
[86] His decorative outer coffin is painted with scenes from the famous Book of the Dead, which depict Nesyamun making offerings to deities
[87] Pg 327: The titles in the hieroglyphic inscriptions on Nesyamun's coffin indicate he was god's-father of Montu, scribe of the temple of Montu, scribe who lays out offerings for all the gods of Upper and Lower Egypt, and scribe who keeps tally of the cattle of Amun. Nesyamun's official duties...he took part in offering rituals before the statue of god, and his life was governed by special rules, such as the requirement to be ritually pure.
[88] Professor David brought research on the mummy up to date by highlighting the problem of cardiovascular disease in Ancient Egypt – at least among the elite. As someone in charge of fattening cattle as offerings for the gods, and as a priest and therefore someone privileged to receive those offerings as payment, Nesyamun’s health seems to have suffered as a result of all the rich food he ate.
[89] The Egyptian Nesyamun (Fig. 1) lived during the politically volatile reign of pharaoh Ramses XI (c.1099–1069 BC) over 3000 years ago, working as a scribe and priest at the state temple of Karnak in Thebes (modern Luxor)...These combined studies revealed that Nesyamun had died in his mid-50s
[90] It was inclosed in a coffin of sycamore, covered with paintings and hieroglyphical inscriptions, which retained much of their original brilliancy of colouring.
[91] His decorative outer coffin is painted with scenes from the famous Book of the Dead, which depict Nesyamun making offerings to deities, while the text prays for success and in the afterlife and contact with the gods.
[92] The mummy described in the work now before us was sent to London from Trieste, to which place it had probably been trans-mitted from Egypt by that celebrated spoliator of the Egyptian sepulchres, M. Passalacqua.
[93] The coffin was first collected by the Leeds Philosophical and Literary Society and was bought to Leeds in 1823 having been purchased from bullocks museum in London.
[94][Adam’s apple] It is one of the most significant external landmarks in the neck...It is notably more prominent in men than women, increasing in prominence as a secondary male sex characteristic in puberty, and primarily acts to protect the vocal cords posteriorly.
[95] It is situated at the top end of the trachea or wind pipe just behind the base of the tongue, the thyroid cartilage of the larynx causing the prominence at the front of the throat known as the Adam's Apple.
[96] The larynx is a cartilaginous segment of the respiratory tract located in the anterior aspect of the neck...It also contains the vocal cords and functions as a voice box for producing sounds, i.e., phonation.
[97] The sound of your voice is produced by vibration of the vocal folds, which are two bands of smooth muscle tissue that are positioned opposite each other in the larynx.
[98] Longitudinal settings describe the state of the long axis of the vocal tract such as larynx height and protrusion/retraction of the lips.
[99] The vocal tract area extends from the glottis to the lips and is surrounded by various structures such as the larynx, the epiglottis, the velum, the tongue, and the upper and lower lips. (And See Figure 1)
[100] The human vocal tract system starts at vocal cords, or glottis, which takes place under
Esophagus in Figure 2.4 and ends at the lips. The average length of male vocal tract is
2 approximately 17-17.5 cm and the cross sectional area of the vocal tract is 20 cm
[101] The human vocal tract is basically a tube with two flaps just above the lungs and its diaphragm muscles, which pump out air (Figure 11.6). The vocal tract is much like a saxophone, with the reed vibrating at the top of the tube. Our vocal flaps can vibrate faster or slower, producing higher or lower pitches
[103] When entering the CT scanner, special lights may be used to properly position you, and you may hear slight buzzing, clicking and whirring sounds as the CT scanner moves during the imaging process.
[105]While each scan is taken, you'll need to lie very still and breathe normally. This ensures that the scan images aren't blurred. You may be asked to breathe in, breathe out, or hold your breath at certain points.
[106]Methods from David’s previous 3D VT prints: The MRI data were then segmented with the open source code ITK-Snap, to rebuild a 3D Vocal Tract, whose .STL file was then sent for 3D rapid prototyping. The material used was VeroWhitePlus Opaque.
[107] Given the visual similarity between 3-D printed vocal tracts and the pipes of a pipe organ and the possibility of exciting them musically via a keyboard to create a choral vocalize, the instrument has become known as the “Vocal Tract Organ.”
[108] This paper describes the use of 3-D printed models of the vocal tract for different vowels that are used to create an acoustic output when stimulated with an appropriate sound source in a new musical instrument: the Vocal Tract Organ.
[109] Here is a video of David Howard demonstrating how the eLarynx works
[110] The vibrations produce sound waves that travel through the throat, nose, and mouth, which act as resonating cavities to modulate the sound. The quality of your voice—its pitch, volume, and tone—is determined by the size and shape of the vocal folds and the resonating cavities. This is why people's voices sound so different.
[111]The tract incorporates a coupler at its larynx end that is designed to fit snugly over the output end of an Adastra model 952-210 (16 ohm, 60 Watt) loudspeaker drive unit.
[112] Supplementary Video for audio from Nesyamun’s 3D printed vocal tract
[113] The measured lower three formant values for the vowel of Nesyamun fall between the vowel in ‘bed’ and the vowel in ‘bad’ within the formant data quoted in the classic 1952 work by Peterson and Barney21, based on the closeness in frequency of the second and first formants respectively.
[114] A fully functional oropharyngeal complex is essential for normal feeding, breathing, and speech sound production.
[115]Given the dominant role of speech in human interactions, an overwhelming proportion of the research on tongue movement focuses on its role in speech, specifically vowel and consonant production.
[116] The human face... influences the acoustics of speech by determining the shape and size of the opening of the acoustic tube produced by the vocal tract
[117]The tongue, however, has lost its muscular bulk over time
[118] Another caveat is that the scan David has of Nesyamun’s vocal tract is from a lying down position, as Nesyamun was posed in his coffin, his head tipped back. (An issue for living subjects, as well, since they are lying down in the machine): It should be noted that the effect of gravity on the supine rather than upright vocal tract could influence to a small degree the surrounding positioning of the tract walls.
[119] Supplementary Video for audio from Nesyamun’s 3D printed vocal tract
[120] Only those able to verbally confirm that they had led a virtuous life were granted entry into eternity and awarded the epithet ‘maat kheru’, ‘true of voice’14, as applied to Nesyamun himself throughout his coffin inscriptions. In these texts, Nesyamun asks that his soul receives eternal sustenance, is able to move around freely and to see and address the gods9 as he had in his working life. Therefore his documented wish to be able to speak after his death..