A Naked Year!
HAPPY NAKED NEW YEAR! From talking whales to training astronauts, creating life to reversing life-threatening allergies, Georgia Mills, Izzie Clarke and few other familiar voices re-visit their favourite moments and the biggest scientific celebrations of the past year.
In this episode
Killer whale imitates human speech
Jose Abramson, Complutense Universidad Madrid
Killer whales, or orcas, are well known to talk amongst themselves, but this week one individual was recorded mimicing human sounds. Georgia Mills has the story...
Georgia - This is Wikie. She’s the first killer whale ever to be recorded imitating human speech.
José - The point here is that we didn’t want to teach English or a language to the killer whale.
Georgia - That’s study author Jose Zamorano Abramson from the Complutense University of Madrid. So why did they do it?
José - Vocal imitation is a hallmark of human spoken language. It’s very important in the evolution of human culture. We think that studies in other species has revealed that the ability to copy sounds from other members of their own species among primates is mostly unique in humans.
Georgia - Our ability to mimic is an important part of the development of our language, but it’s largely absent in our closest cousins - apes, despite their name, can't. It is seen in a few other species - famously parrots - and in marine mammals. Killer whales are particularly interesting because scientists have seen that different groups, or pods of whales have different dialects - just like accents…
José - Most biologists think that these dialects are acquired non-genetically - they are probably by social learning.
Georgia - To test whether this really was the case, José and his team saw a 14 year old orca, Wikie, could successfully imitate new sounds either made by another killer whale, her calf Moana or by a human…
Wikie had previously been trained to imitate sounds but these ones were selected to be completely alien to her usual repertoire...
José - First we found that killer whales made recognisable copies of novel sounds of killer whales and even human sounds or words - they did it quickly, so we found they are flexible, open, vocal learners. They have the capacity for vocal learning and for vocal imitation. Our results are also remarkable if you think that there was no extensive trial and error training. The sounds were presented in the air and not in the water so it was a very artificial medium for her. Also, the sound production system greatly differs from humans’. They use another vocal structure than humans so it’s remarkable that she was capable of copying our human sounds.
Georgia - Audio analysis software was used to make sure the imitations really did match up with the target sounds, although some of them were better than others…
José - We support with these results the hypothesis that dialects of certain natural populations are learnt by imitation, which means that these dialects can be seen as vocal traditions or cultures. If they have, by vocal traditions, cultures and dialects are an important part of these traditions, dialects can also serve like a social function like accents, for example. Killer whales can differentiate where are the members of their group or from other families just by the dialects, and they can announce cooperation, for example.
Georgia - What does this mean for our own treatment of these marine mammals? José points out if they do learn socially from one another, taking a member out of a pod can be more damaging than we thought…
José - You know that if you capture a killer whale or other animals that rely on social learning and some animals are very important for their social knowledge. You can have a lot of damage if you took or you kill the animals that have the knowledge because different animals play different roles in the social structure. The same thing happens when the killer whales are in captivity, you can’t release a killer whale that is captive in the ocean because she relies on social learning. So you really need to teach that killer whale the special culture, dialects or the way they hunt, or whatever, to introduce them if it can be introduced.
06:27 - Reversing Peanut Allergy
Reversing Peanut Allergy
Pam Ewan, Cambridge Peanut Allergy Clinic
Here's a favourite chosen by Chris Smith from a show we made about allergies earlier in the year. Allergies can vary widely in severity. While some are undoubtedly inconvenient, others can actually be life threatening. Chris Smith and Katie Haylor tackled the topic and first up, Katie went to see 8 year old Dillon, and his mum Maaike. Chris was then joined in the studio by Pam Ewan from the Cambridge Peanut Allergy Clinic.Maaike - When Dillon was about 18 months old he was in the garden with his dad and his brother filling up bird feeders with peanuts and had an immediate reaction which resulted in us ultimately being diagnosed with peanut allergy.
Katie - How does it affect your day-to-day?
Maaike - It becomes the most important thing in your life. It makes your world very small to begin with. It’s huge in its detrimental effect on family life but, luckily, we have the resources and the kind friends and family to make it possible to do lots of normal things.
Katie - Dillion, what’s it like having a peanut allergy?
Dillon - Well, it’s a bit hard because we have to check the labels of most things. And, at like a birthday party, they have a cake with peanuts and I have to just deal with it and not have it.
Chris - And we’ll hear a bit more from Dillon and Maaike, later in the programme. But first we’re joined by Pamela Ewan. She is a consultant allergy specialist at the Cambridge Peanut Allergy Clinic and she treats people just like Dillon.
Chris - Why are those allergies so severe Pam?
Pam - Well, no-one really knows why peanut allergy is so severe, but of the foods it’s the one that is the worst so it’s the most common of the foods to cause very severe, sometimes fatal reactions. So it’s a very bad one.
Chris - What age does it tend to kick in at?
Pam - The average age is around two for the first symptom in a child but it could occur at any age and, obviously, that depends a bit on exposure. If you don’t start eating peanuts until you’re older, which is what happens now, probably that age of two is going to go up quite a lot.
Chris - In the population at large, a person picked at random, how likely are they to have a very profound peanut allergy and are you seeing that number climbing, staying the same, decreasing?
Pam - Well, 2 percent of children have a peanut allergy so that means one in every fifty. You could say almost nearly one in every primary school class.
Chris - And has that changed?
Pam - It was very rare to have a peanut allergy until the 1990s. We hardly ever saw a case and there was a big increase in the 90s. It’s gone up, yes, it’s gone up three or four more times since then. We haven’t actually got the latest data so we feel it’s probably leveling off but, without hard data to show that.
Chris - When a person has a very profound reaction what’s actually happening to their body so that they have that collapse and anaphylaxis?
Pam - They’re having this very widespread histamine release which cause a whole range of different symptoms. But particularly in these severe reactions with peanuts the main problem is very bad breathing, so they either get really severe asthma. Even more often closing up of the lining of the throat so they are basically being asphyxiated.
Chirs - How do you investigate them?
Pam - We just put a little bit of peanut solution (an extract of peanut) onto the skin and prick it into the skin. It’s not like a blood test, it’s a very minor thing to do. And you get swelling and redness and itching, so you get a think that looks a bit like a nettle sting.
Chris - And that tells you this person is reacting, so you know they’ve got an underlying allergy? How do you then manage them?
Pam - The current management is avoiding the food, so avoiding peanut. Now that’s tricky because peanut is hugely widely used in the food industry so it’s in loads of things. Not just the things you might expect but it’s added to unusual things so it’s very hard to do that. That’s the mainstay of treatment combined with carrying the medicines to treat reactions, and the particular one for the very severe reactions is an adrenaline pen.
Chris - The treatment that you’ve been investigating is rather than treat the symptoms and rescue people, you’re trying to stop it happening at all?
Pam - Yes. We’ve been trying something called desensitisation. What that involves is trying to reprogramme the immune response, switch off the harmful allergic response and instead induce a beneficial response. It’s not usually possible to do it totally but you can certainly downregulate the bad response and upregulate, increase the good response.
Chris - How do you do it?
Pam - We start with very small amounts of peanut and it’s given by mouth, taken every day. And every two weeks the patient comes back to our clinic, we increase the amount they’re given and then they take that same dose at home, so every time they have a bigger dose they’re in a safe environment with doctors and nurses. It takes 14 weeks to go from a very tiny dose up to taking between 1½ and 2 peanuts equivalent. It’s not given as peanuts but it’s given as a measured protein, peanut protein.
Chris - We’ll hear how Dillon got on…
Maaike - There’s quite a lot of peanut flour in there.
Katie - Maaike, you’ve got what looks like a chocolate mousse pot…
Maaike - And we open the capsule carefully over the mousse and then we mix it in. Good job.
Dillon - Yes!
Maaike - It’s given us the freedom to engage in usual family life, and go on holidays, and in the event that Dillon is accidently exposed to peanuts somehow, he will will be able to tolerate that much better than he could before.
Chris - So you heard there they’re sprinkling little bits of peanut extract onto something he likes eating to make sure he continuously presents the particular thing he’s allergic to. But why does that work Pam? Why does that downregulate the profound response he was having before?
Pam - It is changing the regulatory cells that are in the system which control the production of this allergic or harmful antibody so it’s trying to reduce the production of that. And we can show that by monitoring these patients with these tests that the allergic antibody gradually declines.
Chris - What stage are you at with this though? Because we heard from Dillon, he’s one of your patients. Is this something that people can routinely come and seek out from you clinic yet?
Pam - No. Well, we’ve done a lot of research, which has been published, which clearly shows the treatment is effective. What we’re doing now is offering a sort of early access to treatment. We haven’t got a licensed medicine. So we’re well on the way to that and we’re coming up to the last step in the pathway. We’re doing that but, in the meantime, we’re offering this early access to treatment. We’re doing it in the Cambridge Peanut Allergy Clinic where we offer this treatment as part of a range of services we offer. Unfortunately, we’re only able to do this privately because the NHS have not yet commissioned this and are unlikely to do so until we’ve got a full license. So it’s restricted, but it works on most people. We have currently in our clinic we’re having success in high 90s - 95 percent plus patients we can achieve this, so pretty impressive.
14:44 - A brief history of A Brief History of Time
A brief history of A Brief History of Time
Matt Middleton, University of Southampton
In 1988, Stephen Hawking released what was to be his seminal science book, A Brief History of Time. It has sold millions of copies in multiple languages. But many people admit to never making it past the first few pages, earning the book the accolade of being the most popular unread tome of all time. If you did the same, former Cambridge astrophysicist Dr Matt Middleton, who's now based at the University of Southampton, has a brief history of A Brief History of Time to bring you up to date...
I can’t possibly do the content, nor impact, of this famous book justice. “A Brief History of Time” was Professor Hawking’s way of placing the wonders of the cosmos within reach of everyone with a curious mind. It has helped shape and inspire a generation of eager scientists, and I count myself amongst their number. But, in any case, I’ll try and break his famous book down, by telling you about my favourite bits of the physics it explores. Here’s a very brief history of A Brief History of Time.
Stephen Hawking worked extensively on black holes – from the mindbending nature of singularities to the establishment of black hole thermodynamics, before we had any evidence they existed,, and now they’re a main-stay of observational astronomy - from hot gas clouds pulled apart by SUPER Massive Black Holes to smaller black holes stripping material from a companion star. More recently, LIGO confirmed their presence from the detection of gravitational waves as two spinning black holes collided and merged together. I’m sure Prof Hawking was also excited by the prospect that we might soon see a black hole for the first time.
Telescopes all around the world lined up to create the biggest telescope ever - The Event Horizon Telescope. The path of the light near a black hole is bent by gravity resulting in a shadow that we can observe with this extremely high resolution instrument
This gravitational light bending- the idea that the path of light can be affected by gravity, - is presented in a Brief History of Time. It is a direct consequence of General Relativity, which predicts that both the paths of light and matter are affected by massive objects. It is now used extensively in the discipline of ‘lensing’ where massive objects or collections of objects (such as clusters of galaxies) can bend light around them. When they intersect, they amplify light, so we can detect and study very distant objects. This study of distant objects connects rather nicely to other themes in BHoT, notably the expansion of the Universe.
By looking at how light from distant galaxies is shifted compared to light you might see in a labratory, Edwin Hubble famously confirmed that galaxies were (almost exclusively) retreating from us – a notable exception is Andromeda which will collide with the Milky Way in a scant 4 billion years. The realisation that the Universe is expanding remains one of the most important in human history.
Extrapolating backwards inevitably results in a point in time where all the Universe’s mass was contained in an extremely small space - the explosion of space and time from which the Universe emerged was dubbed the ‘Big Bang’. Stephen Hawking worked extensively on this concept and naturally it features heavily in a Brief History of Time
When we look at the residual light and radiation from the big bang - known as the cosmic microwave background - the fluctuations are so extremely small in any direction that we look, we know that the universe was once incredibly compact, and expanded very very quickly. When I say quickly, we can work out it expanded in 100 millionth of a trillionth of a trillionth of a second, by a factor of 1050, a number so large I don’t even have time to say it.
In fact this ‘inflation’ was faster than the speed of light – but don’t panic, the expansion of the Universe doesn’t have to obey the speed of light. We think this inflation is down to something mysterious called vacuum energy (also called Dark energy or Quintessence).
One of the things I really love about A Brief History of Time is that it’s about more than just the science; it’s also a story of development and our place in this beautiful cosmos. Stephen Hawking presents a human perspective throughout, navigating our movement away from a Ptolemaic view of the Universe (where the earth was at the centre), through the Copernican revolution of a heliocentric solar system and to the point where we do not inhabit a special place in the Universe at all.
Whilst this may sound a tad bleak, we should take comfort in the fact that the Universe may have been just right for life to develop – referred to as the anthropic principle. If the the Universe wasn’t able to support life then we may not have the stars and galaxies, mankind may never have dragged itself from the primordial swamp and – most upsettingly of all – the Universe may have been denied minds such as Stephen Hawking’s and we may not have had a Brief History of Time at all...
22:40 - Louise Brown: the world's first IVF baby
Louise Brown: the world's first IVF baby
Louise Brown - the world's first IVF baby
On 25th July, 1978, Louise Brown was born. Chris Smith met up with Louise in Grantchester, Cambridge, to find out what's it like to be the world's first IVF baby...
Louise - Louise Brown, and I’m the world’s first IVF baby.
I was four years old, just before I started school, and mum and dad thought it would be best to just say that I was a little bit different to everybody else - the way I was born and conceived. Because children can be quite cruel sometimes and they just wanted it to be so that I was aware that I knew if anybody said anything that I knew about it. I didn’t fully understand it but they showed me the video of my birth and said that was how I was born, slightly different, and they sort of left it there. And I picked up the rest of it listening to mum and dad being interviewed. If I have any questions for mum and dad I could ask them and they’d explain it to me.
Chris - Do you get a lot of attention?
Louise - On special occasions, yes. Whenever my birthday has a nought or five on the end of it people seem to get excited, so I’m semi-used to it.
Chris - When did it sort of dawn on you how special the process that resulted in you was?
Louise - I think I must have been between 12 and 14. It was mainly coming to events here at Bourn that brought it home. When you see all the children and people used to say yes Louise, and you’re the very first, and also the press wanted to take pictures or interviews. None of my friends did that.
Chris - I wondered when you said about 14 because that would coincide with sex education at school and that kind of thing. I wondered if that was what began to hone it down in your mind?
Louise - Yeah, definitely. Because I can remember we had, when I was in senior school, I went into the science lab and opened the science book and there was a big picture of me in there. And the teacher said yes Louise, you’re in this book and I was all embarrassed surrounded by test tubes and bunsen burners and things like that, so yes. My son’s 11 and he is aware now of the difference, the way I was born to the way he was born.
Chris - Are you an only child?
Louise - No. My mum went on four years later to have my sister Natalie. She was born in 1982 and she was the world’s 40th.
Chris - 40th test tube baby?
Louise - Yes, yes.
Chris - Do you like that phrase “test tube” baby because it doesn’t really involve a test tube does it?
Louise - I prefer IVF now. Everybody says IVF and I prefer that.
Chris - Now when you came to have your own kids did it cross your mind at all or even before you had them, you were born in a slightly special way, might there be consequences for your own fertility? Did that cross your mind?
Louise - I was always asked as I got older growing up would I consider IVF, and, obviously, yes I would, but I never actually thought I would need to. And this is the problem, you don’t think about it when you’re younger. And then, once I got married two years later, we had Cameron so I didn’t sort of think about it. I just assumed, like most people do, that you’ve got no problems.
Chris - And he came along naturally?
Louise - Yes.
Chris - Do you get asked by people about whether or not you’re healthy? Because one of the worries that was expressed, even James Watson DNA pioneer, was suggesting things like we are playing God. We are potentially damaging the genetic integrity of the human race. Do you ever get asked that sort of thing?
Louise - People do ask if I’ve had tests. I know I had a lot of tests when I was first born, but that’s it, I haven’t had anything since the day I was born.
Chris - And otherwise you’re pretty hale and healthy?
Louise - Yeah, absolutely fine. I don’t have any problems. Conceived naturally. Yeah, I’m fine.
Chris - What was the reaction of your parents to your arrival?
Louise - I don’t think mum got to see me until the 26th July because it was a C section, so she was knocked out. I think my dad, as I recall seeing on a video, I think he was shaking and had to give me back to the nurses because he was like... I don’t think he could quite believe it.
Chris - When you come back to Bourn Hall now, because obviously the people who made yourself - a bit of a strange concept that isn’t it, then set up Bourn Hall and have now helped tens of thousands of people since, what’s it like you come back?
Louise - It’s almost like my second home. I love spending time with the people here. It’s beautiful grounds and I’ve also got really good memories of all four people that are unfortunately no longer with us there. So I love coming back.
Chris - One of the staff at Bourn Hall said to me it’s quite unusual because when people come to have embryos put back they often bring their mum and it’s not normal that your mums present at your conception.
Louise - No, it’s a bit weird. My mum wasn’t present as my son’s conception…
Chris - Any parting message for anyone?
Louise - Yes. If you’re an IVF child then, we rock! And if you’re thinking of having IVF go for it. Mum believed it would work and there are now nearer I think 8 million of us. So yeah, go for it.
30:10 - The physiology of dancing
The physiology of dancing
Prof Emma Redding, Trinity Laban Conservatory
What actually goes on the body when we’re dancing? How easy is it? It’s probably a pretty uncontroversial statement to say that dancers are fit, but how fit are they? To find out more, Adam Murphy and Izzie Clarke put themselves to the test with Emma Redding, Professor of Dance Science at Trinity Laban Conservatory of Music and Dance…
Emma - There are huge demands placed on dancers in terms of physiological demands. If you just look at how they take their bodies to huge extremes so in terms of joint range of motion they really do need to get their legs up. I mean they probably, I would say, dancers need to be more flexible than pretty much any other athlete. But, if you look at their upper body strength, and some of their cardiorespiratory fitness sort of areas, then dancers are less fit than many of their counterparts. Many sports athletes are actually fitter than dancers but that’s not because they don’t need to be fit, that’s just because the training needs to really support that fitness for the way in which choreographic demands are changing all the time.
Adam - So do dancers experience injuries at roughly the same rate as other athletes?
Emma - Dancers get injured a lot. Research has shown that 80 percent of dancers get injured in any 12 month period of time. That’s an injury that takes them out of participation. 80 percent of dancers, that’s a lot of dancers. And if you apply the same definition of injury and the same type of research to sports athletes, you’ll find that dancers actually get injured more than many other sports athletes, including rugby players, you know, and they’re killing each other. But actually, they get injured less, perhaps more catastrophic, but they get injured less than dancers. So it’s interesting and I think that one of the biggest causes of injury is fatigue and overwork, so that means we can do something about all those injuries in dance. Look at the training programmes, apply some science, and actually try and prevent those injuries.
Adam - But what does this application of science look like?
Scott - Well, this is the hand grip dynamometer. This is an isometric measure of strength. So we’re looking at particularly the forearm here, and the wrist.
Adam - That’s Scott Sinclair. Lab technician for Trinity Laban’s Dance Science Dept. Who had a test of strength for fellow Naked Scientist Izzie Clarke.
Scott - This is important, particularly within music and dance. One for musicians because they’re holding an instrument for quite a long period of time so if they’ve got an imbalance in their muscle weakness they’re more susceptible to injuries. The exact same principle as dancers; they’re working with the floor, they’re working with partners, so if they have a weakness or an instability, again, that could lead to injury as well.
Izzie - Okay. I’m so weak. I already know. I’m going to be so bad.
Scott - You just want to hold it in this position and squeeze as hard as you can for three seconds.
Izzie - Okay, right. Deep breath.
Scott - Ready… three, two, one, squeeze. Go go… one, two. three, and relax.
Izzie - Oh gosh. I wouldn't even know what that was.
Scott - That’s a three zero. So that’s measured in kgs. The most important bit really is just keeping it individual to you rather than comparing you to populations, for example.
Adam - That is all very helpful for dancers. But what about those of us who still struggle to clap in time? Back to Emma Redding…
Emma - One of the big things we’re trying to do here at Trinity Laban in dance science is to measure the impact of dance on the health and wellbeing of other populations. And there’s been a lot of anecdotal evidence really in the press and magazines and on TV about what dance can do, and dance is certainly more popular than ever before. More people are doing dance and watching dance, funnily enough. And why is that, what is it doing for them? And that’s we’re trying to sort of measure.
We know that dance can get you fitter. So if it’s seen as a physical activity just like any sport then it can potentially conquer various diseases like obesity, diabetes, cancer, heart disease, etc.
What else can dance do? We measure the psychological impact of dance, and we’ve found with some of the research projects we’ve done, we’ve found that, for example, older people can increase their self-esteem, their sense of identity and purpose and meaning in life through dance participation.
Adam - Do you have any theories as to why it does that?
Emma - Yes. Dance is not just a physical activity, it’s a social activity whereby people are touching each other, they are interacting with each other. Trying physically and cognitively to solve those problems together. So I think it’s the social, the cognitive, and the physical aspects of dance that makes dance a very unique activity and can produce the benefits that go way beyond sports.
Adam - We decided to put this to the test and went for a dance class with Emma who was more than happy to put us through our paces with a simple contemporary routine…
Although how simple it actually was is up for some debate…
Izzie - I obviously can’t tell my left from my right apart. One left, one right... got it. Change direction… I don’t got it.
Adam - And at the end of the somewhat successful class, had Emma proved us right? Were there real psychological benefits?
Emma - Well, I can see you’re smiling. So I think it’s fair to say that yes, there are lots of psychological benefits. I can see them now. And what's happening essentially is those exercise endorphins that are released when you do any physical activity, they are being released right now. So you’re feeling good about yourself, you’re feeling happy. Everyone seems to walk out of dance class with a smile on their face.
Adam - Are there any particular groups of people who benefit most from getting involved in dance?
Emma - No. I would say all types of people, no matter who you are, what you come with, you can benefit from dance. Every individual that has participated in dance, at least at Trinity Laban, has benefitted in some way. And we do work with older people; we do work with people who have acquired brain injury; younger people with learning differences; people with physical difficulties; we have people in wheelchairs coming in with their carers. And it’s really important for us as well to not only work with the people who have those differences but their carers, their physiotherapists, occupational therapists so that they can go out of the building and actually continue to be creative physically with the people looking after them as well.
37:07 - How do planes fly?
How do planes fly?
It’s incredible that we can fly so high. In fact, how do planes get off the ground, and stay in the air? Chris Smith was joined by gadget whizz and Naked Scientists veteran Dave Ansell in the studio to tell us, or should we say, show us...
PA ANNOUNCEMENT - We’ll be cruising at an altitude of 60,000 ft and a speed of 1,000 mph. In a few moments time, we will be moving through the cabin to offer some refreshments.
Chris - Oh good. I am feeling rather thirsty. Right on cue.
Izzie - I think some snacks have just arrived.
Chris - And a very beautiful stewardess
Stewardess - Champagne, sir? Caviar, madam?
Chris - Have you got anything better than that?
Stewardess - No.
Chris - The thing about flying is that you have to actually know how your aeroplane works in the first place. It is amazing that aeroplanes even fly. You think of a fully laden A380, for example, there are 800 people plus on there. So we thought we would do an experiment to explain how flight actually works and how aeroplanes and wings work. So who better to ask than kitchen science veteran and actually whizz making science experiments to show how things actually work and that’s Dave Ansell. Welcome to the program Dave.
Dave - Hello!
Chris - What have you brought in?
Dave - I’ve got a lot of gadgetry here. I've got a big fan and model wings and things. Start off thinking about how planes fly is how you stay up in the first place. Everything is being pulled down by gravity and the fact you're not falling through the floor must mean there's a force pushing you upwards. And at the moment you're achieving that by applying a force downwards onto the chair and then Newton's laws mean that every action has an opposite reaction. The chair is pushing upwards with exactly the same force and holding you up so you don't fall to the center of the earth very quickly.
Chris - Right. So how does the wing of an aeroplane create that force, which then leads to the airplane being able to stay up in the air and combat gravity accelerating downwards?
Dave - So it must be pushing down on something and the only thing a plane has got to push down on is the air around it. And the part of the plane which holds it up is of course the wing. So I have a model wing here, which is made out of a bent piece of card, and we’re going to be wanting to see how the wing is affecting the air moving past it. Now to get any lift from a wing, you need the wing to be moving through the air. Now to see that while it's running around is very difficult so I’ve got a big fan which I can turn on and produce air flying past the wing.
Chris - Right. So we have a bent piece of card which is curved in the shape of a wing. You have a screwdriver with a ribbon on it, which is going to reveal where the air is going. So talk us through what will happen when we put the wing in front of this large fan. What should we be looking for?
Dave - In order to stay up, the wing should be pushing the air down, and we should to see that by the ribbon behind the screwdriver being pushed downwards.
Chris - Now I can understand how that will work with the bottom side of the wing because the wing is higher at the front than the back so air hitting the wing is going to be deflected downwards. So if you push the air downwards, it's going to push the wing upwards, as Newton's law tells us. What about the top of the wing though, does that contribute to the lift?
Dave - If you get the aerodynamics right, which is important part designing a plane, then air will tend to stick to a smoothly curving surface. So with any luck you will also get the top of the wing deflecting the air downwards and also producing lift.
Chris - So you get lift from the top of the wing and because you're pushing down with the bottom of the wing you get lift there too.
Dave - Exactly right.
Chris - Let's do the experiment then. This is noisy everyone at home so we apologize in advance. Here we go. So Dave’s turned on his large fan.
Dave - So at the moment I've just got the streamer ribbon moving in the air and it's is going horizontally. Now if I move the wing down towards it from the top you should see that that stream is being deflected downwards even though it's not actually touching the wing.
Chris - Yes, indeed. So the streamer is nowhere near the wing it's underneath the wing but the streamer is curving downwards just like the same shape as the wing. So there's obviously air being pushed downwards by the lower surface of the wing.
Dave - Exactly right. And similarly if we bring the wing upwards towards the ribbon from underneath the air starts to stick to the wing. So the air go over the top is also being deflected downwards and so pulling up the wing. So if I let go of the wing it moves upwards. It’s producing lift.
Chris - One last question for you Dave then. What about when a plane flies upside down when a stunt pilot goes upside down the plane still flies. How does he do it?
Dave - It's exactly the same principle. The plane is at an angle so the air hits the wing of the angle and you have to float you downwards so air pushes the plane upwards.
Chris - Are you saying the pilot basically has to modify his flying technique or her flying technique so the wing is still pushing downwards.
Dave - Basically the nose of the plane is pointing up a bit more if you're flying upside down than if you're flying horizontally because they're designed to fly right way up.
Chris - High angle of attack I think is the correct parlance, isn’t it?
Dave - It certainly helps.
42:58 - Astronaut training for beginners
Astronaut training for beginners
Alec Stevenson, QinetiQ
What would a trip into space feel like? To find out, Izzie Clarke spoke with Alec Stevenson, from QinetiQ, and she got put through a taster of astronaut training...
Alec - We're at the human centrifuge facility in Farnborough. At the moment it's the only human rated centrifuge we have. It’s a great big spinning arm, it's about 34ft in radius, or 60 ftt in diameter and it's been here since 1955. Primarily in the early days was to research the effects of these G forces on humans. More recently to train our fast jet pilots how to cope with the forces they experience when they maneuver in their aircraft, and we also do a bit of space research. In fact, we’ve done some training space tourism to the International Space Station, and now recently doing some research looking at the respiratory effects of high G forces.
Izzie - So basically, to put it very bluntly, it's a little pod on a massive metal arm. It gets spun around very very quickly
Alec - That in essence is what it is yeah.
Izzie - Now I can just see our first victim has climbed into the centrifuge. Tell me, what actually happens once this giant arm starts to spin?
Alec - The arm takes a bit to start going, it’ll idle around the room a bit and then the motor will kick in. And how we’ve set it at the moment, it will accelerate at 1G per second. If we go to 3G it will take two seconds to get up there, so very quick, and then sustains that level for how long you want. For today, I think we'll just keep it to 15 seconds. Now what the person in the pod feels is that there is a sudden increase in their weight. So moving their hands and arms around is much more difficult. Also because their weight their blood has increased it will tend to head downwards. What they might experience depends on how low the blood pressure drops as a loss of vision and that's caused because the eye has actually got internal pressure to hold it in that spherical shape, and it's harder for blood to get back into that eye. You lose your vision first and once you've lose lost your vision that's when you end up not going enough blood to the brain and therefore and then you end up losing consciousness but hopefully we won't get that today. We'll just see a bit of visual loss which is very dramatic and easy to see.
Izzie - Does this mean we can have can have a go?
Alec - You can indeed have a go.
Izzie - Oh my goodness, I better go and suit up!
Okay. So I didn't actually have to wear a spacesuit which was rather disappointing. I climbed into the small pod ready for a spin.
ENGINEER - Isabel? Hi, can you hear us?
Izzie - Yup.
ENGINEER - Hello, control? If you’d like to set us up for 2.4G run. We'll take that as our first taster for 15 seconds. Then if you happen at 2.4 we can take you up a few steps beyond that.
Izzie - Perfect
CONTROL - Two point four for 15 seconds. Stand by…
Izzie - Here we go!
Initially, I’m sat upright but as the pod accelerates around the circular room, I’m tilted sideways. The top of my head pointing towards the centre. This causes the blood to rush down towards my feet, much like a pilot would experience in flight/
Engineer - And you can talk to us?
Izzie - YEAH! It’s okay. I was expecting it to be quite intense but it feels like a giant rollercoaster.
...In fact by my fifth run. We took it to a maximum for a newbie like me. Up to 4.2G. And yup, my vision disappeared. Tensing legs and stomach muscles you force the blood back up towards your head and suddenly your vision clears. Hopefully. Whilst I recovered from the motion sickness, Alec explained why it's important to run these practices.
Alec - There’s a medical thing. We need to check that the actual forces that were subjected are pilots and astronauts to don’t cause them any physical harm. There's a familiarisation piece as well, because it's an unusual sensation that they wouldn't normally expect to have in life. Particularly for astronauts, those sorts of accelerations are just really for space although it's not necessarily for that kind of acceleration, that Chest-to-back acceleration, training per say we can do. It's the sensation that there need to be familiarized with so that they can get on with what they should be doing - concentrate on the task they may have to do in the spacecraft. As you were about 4G, we should be able to get you up to 9G with the kit that we've got and some training.
Izzie - I don’t think I’m quite ready for that. The sensation in your body is so strange. Everything feels a lot heavier as astronauts take off their lung feels so heavy. Does that have any health implications. How can we even study that?
Alec - It does have health implications, it does affect how your lung works and obviously a lung is very important. It's how we get option into our blood. So one of the things we can, we can measure how that acceleration affects the amount of auction you get in the blood and we've probably all seen a lot of clinical programs where we've seen a little clip that you get on your finger, it's called a pulse oximeter, which measures that percentage of oxygen that's the hemoglobin saturated with.
We can do that and we can see that that is markedly reduced when we are under that sort of acceleration. The good news is, when we turn the acceleration off that tends to return to normal. As the lung as quite spongy, it distorts under its increased weight. What you end up doing is stretching the top parts of the lung, the top the parts are at the chest, and the bottom parts of the lung which are in your back, they get compressed. There is an element of that when we're just lying on our back. But because it's only 1G, there's only a slight difference between the top on the back and as we increase the levels of G that just amplify that difference.
So we're concerned, I suppose under GX, that we get a part the lung at the base that's gone under so much pressure that it cannot actually closes off and doesn't communicate with the atmosphere, because it can’t get air into and out of the lung, the blood that flows through it just doesn't pick up any oxygen. It contributes to what we call a pulmonary shunt, a proportion of the blood that were pumping out of a heart that doesn't actually pick up oxygen. It runs through the lung and obviously that mixes with bits that do pick up oxygen and just lowers the average saturation we've got.
Now the issue with the top part of the lung is that it gradually gets stretched and stretched, and like any mechanical component, will eventually cause damage if you stretch it too much. A lot of the stuff that we’ve done suggests that the levels we're doing are safe. But there is a degree of stretching there. We need to be careful that if we've got some individuals who already have issues with that lung that if we stretch any further are we actually then going to cause an issue, a tear or something like that. So it’s something we need to consider.
50:42 - Raising a glass to the chemistry of wine
Raising a glass to the chemistry of wine
Alex Thom, University of Cambridge
It's time for Georgia Mills' favourite moment of 2018. And, for whatever reason, 2018 certainly featured a fair amount of wine tasting. There was the “taste” show in April, where we explored different flavours. Izzie tried beer fermented with saliva more recently (not the best!). But then there was our punting show back in summer… Where Chris Smith and Georgia punted down the Cam, picking up and dropping off scientists along the way. Including Chemist Alex Thom who created some experiements with wine...
Alex - I’ve brought an interesting wine here called a Reisling - that’s the grape, and I chose it because one of the important constituents of wine is the acidity. That’s what often makes the juicy feeling in the mouth for wine and I wanted to play with the idea of changing the acidity of wine and to see what the flavour changes.
Georgia - Oh, so we can actually change the acidity even though it’s already been made, put in the bottle, we can tinker?
Alex - The joy of chemistry is that we can play with some of these elements in a controlled fashion. Let’s try it as it is and we can comment on it, and then I can tell you what the official tasting notes say.
Chris - I love this. You can tell you’re a chemist, Alex, because you’ve got a pyrex beaker that you’re going to drink this out of.
Alex - Actually I got this at the International Chemistry Olympiad this year, so that was a gift there. It’s great.
Chris - It’s fantastic. It’s literally a pyrex like you would put on a retort stand on a gauze and boil away in a laboratory but it’s got a handle on the side.
Alex - I’m going to put a little of the Riesling in the glasses first. This is the unadulterated wine, as such, and we’ll taste that. Give it a swill in the glass maybe, get some of the flavour out.
Chris - I’d say that’s quite an acid wine.
Alex - It is, yes. I picked it because it’s a Riesling which is known for one of the most acidic wines. That can be good and bad. People like acidity because it means they keep longer, they age longer, but if it’s too acidic it becomes sharp and horrible. So this is wine you might have on a hot summer’s day - a bit like today and the acidity makes it feel more refreshing.
Georgia - Very very nice. Can we see what happens when we change that acidity then.
Alex - Yes. I’m going to do a little modification to the acidity here so I’ve poured some of the wine into my beaker and we’re going to add to it some bicarbonate of soda. Now this is an alkaline salt basically. It’s just a standard kitchen chemical but… Because we’re on a punt it’s quite difficult to judge quantities and do this correctly, so into this wine I’m going to cheat and add a little bit of a homemade indicator. I’ve made this out of red cabbage last night. Hopefully it won’t change the flavour too much. But this wine is currently a nice sort of yellow colour and if I add a bit of this it should change to a startling pink colour, hopefully. And I can use this indicator to tell me how acidic the wine is, so this very pink colour means it‘s pretty acidic at the moment.
Georgia - it goes bluer when it’s more alkaline?
Chris - It currently looks like rosé doesn’t it.
Alex - Yes, exactly. I’m going to now add to it some bicarbonate of soda and hopefully that should fizz quite happily there, and it’s gone a bit darker purple. So we’re looking for a purplish colour rather than a green colour. If it’s gone too green it’s gone too alkaline.
Georgia - If feels like the acidity might have changed but we’ve also put in cabbage and a lot of soda. Is this really going to tell us anything?
Alex - I chose this partly because I had a red cabbage in the fridge last night. Yes, it’s certainly changed colour now. It’s gone a sort of salmony, maybe very light rose colour rather than the bright pink. It should now smell a lot less as I…
Chris - Yes. It certainly doesn’t smell the same.
Alex - Feel free to spit this out if you don’t like it.
Chris - Have we got a spitoon?
Alex - There’s a jug here we can use as a spitoon.
[Chris spits our wine overboard]
Chris - Oh god. That was grim. Ah man.
Alex - What's happened to it.
Georgia - It’s ruined! That’s what happened. Ugh.
Chris - That was rank.
Alex - It’s taken all that acidity away. What we’ve now got is a…
Chris - It hasn’t just taken the acidity away. It’s taken any semblance of wine away.
Alex - Yeah. And it basically tastes horrible.
Georgia - It’s like drinking washing up liquid or something.
Alex - Yes. I may have added a bit too much of this. The flavours I can still get - you can still taste the alcohol in this. So it tastes like a shot of alcohol but without anything much else.
The next experiment is to see if we can put the acidity back with a different acid. And so acidity is really really prized in wines because it gives them flavour, so most of the flavours disappeared as well. And if you’re in a really hot climate the grapes tend to turn all that acidity into sugar and they lose a lot of the flavour. This is an acid which I’m going to add which is a different acid from the one we had before. Most of the acid in the wine would have been an acid called “tartaric acid” which I’ve got somewhere in here and malic acid.
Chris - You’re making what lysergic acid? It’s a bit different kind of acid isn’t it?
Alex - Lactic! So this is stuff that builds up in your muscles when you exercise too quickly and it tastes a bit like yogurt.
Chris - Well, it’s gone the right colour again hasn’t it?
Alex - It’s gone a nice pink colour again.
Chris - It’s back to pink so we know it’s more acidic again. I’ll give it a go. Go on then.
Alex - It’s pretty tart.
Chris - The smell is back.
Alex - The smell’s back.
Chris - Yeah. The smell, it’s wine again.
Georgia - Yeah, I can smell the wine again.
Chris - It’s back to Riesling that we had before. I tell you what, it’s a lot less disagreeable than what we did with the first effort with the bicarb.
Georgia - It’s like one of those sweeties that's super sour. So the flavours weren't destroyed by that red cabbage goop we put in, they were there?
Alex - Just hidden by changing the ph. As you can see, having a more acidic wine gives the flavours more of a chance.
Chris - You’re really enjoying that Georgia.
Alex - That was a very fine face.
Chris - Do you want some more? A top up?
Georgia - I’m quite alright.
Alex - So that’s what you can do and, of course, winemakers do this on a much more careful scale with acidity rather than just pouring a few things together in a punt.