Gareth Mitchell: Hello, Gareth here. Now, first of all excuse this lousy sound quality. It’s literally just for a few seconds before we start the podcast properly. We’ve literally just heard some very good news that I just wanted to tell you about before we get into the podcast proper. And that is that Imperial students have well and truly cleaned up at November’s Guardian Student Media Awards. Felix won student newspaper of the year and last year’s Felix’s editor, Tom Roberts, who has been on this very podcast actually, won in the student journalist category. There was also a prize for Imperial’s angry geek who was awarded runner-up in the student columnist of the year award. And congratulations also to I Science which was awarded runner-up in the student magazine category. Yes, a definitely big congratulations all-round. I just though I’d sneak that in. Hope you don’t mind too much. But now let’s get on with the December podcast. There’s plenty in it and I hope you enjoy it.

This is the official podcast of Imperial College London. And I’m Gareth Mitchell of the Science Communication Group here at Imperial and I present the BBC’s Digital Planet programme. Hello. And in this edition, to tie in with World AIDS Day at the beginning of December we bring you news of a new DVD co-produced by Imperial College which takes on the stigma around HIV/AIDS in Africa.

Dr Michael Beasley: One of the things that’s most difficult in any society is enabling people to have the courage to go and get tested for HIV. Because stigma is so high there’s always that feeling of folk wanting to say 'it can’t be me. This can’t be happening to me. It couldn’t happen to me'.

Voice: What kills you is the stigma and the discrimination associated with the virus.

GM: And also this month discussion over the future of London’s Heathrow Airport, one of the busiest in the world. We have some expertise on that at Imperial. And one of our top space physicists gives us the latest on the Cassini mission to Saturn.

Professor Michele Dougherty: We turned around and said to the project, hey, we want you to change it slightly. We want to go closer so we can see what’s going on. And so it took a bit of persuasion and I must confess I didn’t sleep very well for a couple of nights before that close fly-by. Because if we’d have flown past and seen nothing it would have been rather embarrassing.

GM: And back on this planet, we’ll have some headlines from around the College too. That’s all packed into the December edition of our Imperial College podcast.

Hans Michels on solutions to London's demand for more air space

Well, December is going to be a key month in British aviation. The government is expected to announce its decision over the expansion of London’s Heathrow Airport. At the heart of it is whether or not to build a third runway at Heathrow. Well, needless to say there are strong arguments for and against expansion and plenty of experts here at Imperial are engaging in the debate bringing their knowledge in from fields like air safety, the environment and transport policy. Professor Hans Michels reckons he has a solution that could unify many of the arguments and I’m with him now in his office in the Department of Chemical Engineering where Hans you are a Professor of Safety Engineering. So are you in favour of airport expansion in London?

Professor Hans Michels: As long as the environmental issues are adequately dealt with I am a strong supporter of aviation and aviation expansion. And if I talk about environmental issues then I mean that includes renewable energy resources but also the impact on the people who live around the airports or the environment as a wider through emission gases.

GM: And first of all just to explain to anybody listening to this podcast from outside the UK, that Heathrow is our main airport. They’ve no doubt heard of that. But can you just give us a rough idea geographically of where Stansted and Gatwick are?

HM: If you’re standing on the east of London Queen Elizabeth then you are an equal distance away from Heathrow, Stansted and Gatwick. Straight to the west, 35 miles, is Heathrow. Straight to the north, slightly to the north-east, is Stansted. And straight to the south, 35 miles, is Gatwick. And London lies to the left. The big London then lies between you the bridge and Heathrow airport.

GM: And the gist of your argument being instead of building a third runway at Heathrow we can just think about the combined force of London’s Heathrow, Gatwick and Stansted airports as in essence a kind of distributed hub. That’s your argument is it?

HM: That’s my argument. First of all because I think that we need some more runways but we have four the argument is always that Schiphol has seven, Frankfurt has got four, Charles de Gaulle Airport has got more. But if you go and look at these airports then you find that you can’t use all these runways at these different airports all the time. And that has got to do with the way in which they were built. So effectively, for instance, depending on the weather, depending on the conditions, depending on the winds, in Amsterdam you can use three at any time.

GM: So even if we accept your argument that Schiphol really only has three useable runways at any time they are nevertheless nice and close to each other. It’s not like London. Ok, we have four runways but the drawback is they’re 30 miles separated. That’s no use is it?

HM: Well, the point is first of all whether they could serve the population. And the argument is often said, yes, but Stansted and Heathrow are less accessible. Well, if you join me and we’re going to stand, say, on Trafalgar Square then you’ll find it takes you about five or six minutes to walk to the nearest underground station and then it takes you about 12 to 15 minutes with changeover to get to Paddington. You’ll be as quick at Liverpool Street station or at Victoria and the train times from there to Heathrow, to Stansted and to Gatwick differ very little, at most 10 to 12 minutes. If you then add on top of that that probably at the airport you’ve got to hang around for an hour or hour and a half may be you can imagine that in the totality of all that a few minutes difference is completely insignificant.

GM: So you’re saying from the centre of London it doesn’t really matter which of these three airports you go to in terms of the time that it takes. If you live outside London I suppose it means that inevitably two of those three airports will be closer than the third one and that seems to underlie the gist of your overall argument as to why you should think of these three airports as a combined London international airport.

HM: And if you want to officialise that what you have to do first of all is to imagine, as you just said, that if you live between Heathrow and Gatwick, for instance in Guildford, what should be possible for you so that you don’t have to travel unnecessarily is that from both thes e airports you can travel to all the places in the world. And if you live in Maidstone then you should be able to travel to all the places in the world between Gatwick and Stansted. And if you live in Hertfordshire you should be able to travel to all the places in the world between Stansted and Heathrow. And if you want to distribute it over the airport you have to have an equal intensity of use.

But then also it means that if you fly in from outside you can be either one of two types of passengers. You can either be a passenger who wants to come to London and then fly on to somewhere else. So he flies, for instance, to Heathrow because he is coming from North America. So he flies in. He comes into Paddington on the train system or the underground and then from there on he does his business and at the end he goes to Liverpool Street station, takes the train to Stansted and then from there he goes to the Far East. But it is also so that if in fact he only wants to come to London, do a great favour for BA Airports and spend a lot of money in the shops there but then goes straight home, and remember that is also half of the people that come to London airports.

GM: So they’re just transferring passengers? They’re just passing through?

HM: They never get into London. And it’s important that we support those people because that makes it a hub. Those people will be told by their travel agent in the States where do you want to fly? And if he says I want to fly to Europe, go to London and then fly to somewhere in Europe like Moscow he’ll say I recommend you fly to Stansted. And if he wants to say no you want to fly to Africa, Johannesburg, he’ll say you fly to Gatwick. And if he says yes but I want to make another connection he’ll say we have a couple of flights. The big airlines all have multiple flights in the day from main destinations. And so you can distribute. That’s why people have a choice. And not only in the main but also for instance BA will say I will fly to a place in the morning and Virgin will say I will fly to the place in the afternoon. So there are options enough for the main connections to make these flights and in that way you can distribute it.

GM: And I know it is a slightly hard concept to put into words but I’ll have a go at summarising it just to make sure I understand it. So what you’re saying is that you can’t fly to all global destinations from each of the three airports but at least two of those airports between them allow you to go to all of those destinations. So it means wherever you’re booking your ticket in the world, wherever you’re trying to get to, there will always be one of the three airports that will allow you to do that.

HM: That’s right. That’s absolutely right.

GM: Isn’t that happening already though to an extent? I mean I know it’s not quite as organised as your model but effectively that’s what’s going on with all these airports. And the other point is that all three of them are operating at incredibly high capacities. I can’t see how just rearranging slightly which flights go from which airport really is going to solve the problem.

HM: Well, Heathrow of course is the one that is really working at 98 or 99 per cent capacity and the one proposal that they have been asking for, which as an intermediate measure I’m not against, is to have both landing and starting from the same runways, which after all Gatwick has been doing for years and we haven’t had any accidents there and I don’t think we will because we can manage that. In the long term, beyond 2030/2035 there will be two runways at Stansted and probably two runways at Gatwick as well. But BAA and the aviation industry do not want to do it until they have squeezed the last possibility of developing Heathrow.

GM: But also there are going to be people living in the Stansted and Gatwick areas who will beg to differ with your assumption that they’re going to put an extra runway in each of those airports.

HM: I totally agree with that but in the end you have to take social responsibility. And here’s a preference. Is it better to put constraints on the environment for Stansted or to put constraints on the inhabitants of west London where the medics tell me that there is a higher incidence of infant asthma than anywhere else in the UK?

GM: So you’re saying if we distribute the flights more so we’re not so Heathrow-heavy that will alleviate some of these asthma cases you’re talking about?

HM: Putting an extra runway in Heathrow or in the area of Heathrow will multiply the amount of emission products by 50 per cent. And if we can disperse it in white lands like in Stansted. Yes, I’m totally in favour of protecting the environment but if you want to have the aviation industry working that way and we need it then we all have to make a contribution.

GM: Hans Michels. Well, still to come I’m off to our St Mary’s campus for a word with the people behind a new DVD which is aimed at tackling the stigma of HIV AIDS in Africa. And we’ve the latest from the Cassini mission to Saturn. Before that though let’s catch up with the latest headlines from around the College.

Headlines from around the College

Imperial researchers working with colleagues in Brazil have found a new accurate way of tracing the origins of zinc in the atmosphere. And that’s quite a step forward because we’ve known for some time how to measure the amount of the pollutant in the air but we couldn’t tell where it came from. At low levels zinc in the atmosphere is actually a crucial mineral taken up by plants an animals but at higher concentrations it’s thought to be associated with cardiovascular, reproductive, immune and respiratory problems.

The new method relies on distinguishing between different isotopes of zinc. Some isotopes, for instance, are signatures for emissions from vehicles whilst others might be associated with the outputs of manufacturing plants. The technique has already revealed that in Sao Paulo the amount of zinc from cars, specifically given off by friction from their breaking, is higher that previously thought. Writing in the journal Analytical Chemistry Imperial researchers from the Department of Earth Science and Engineering say that being able to accurately trace the origin of zinc in the atmosphere should help with better environmental planning and policy.

And also if you have a large waist size you’re at higher risk of dying prematurely even if you’re not actually obese. That’s the stark warning from a study co-authored by researcher in Imperial’s Department of Epidemiology and Public Health working with the German Institute of Human Nutrition and other research institutions across Europe. Even with a body mass index in the normal range risk of premature death rises in a direct relationship with waist size says the research. And it suggests that doctors should measure a patient’s waistline and their hips as well as their body mass index as part of standard health checks.

And you can catch up with more Imperial news by visiting our Press Office website and that’s at It’s also the place to go to find out about events around the College. December highlights include everything from advances in hedge fund strategies to expressing the beauty of maths through poetry. Never let it be said that we lack variety here.


Michael Beasley and Alice Woolnough on a scheme to keep HIV positive teachers in Africa in schools

Well, as you can hear I’m out and about. I’m away from our South Kensington campus and in fact I’m just outside our St Mary’s base near Paddington. Researchers here are behind global efforts to tackle HIV AIDS. And it’s a timely issue. December kicked off with World AIDS Day and that’s being followed by a month of events around the globe dedicated to the issue. And I’m hear to meet some of the team involved with this.

First voice: At the back of my mind I was sure that I was HIV positive. But of course even though you might have that at the back of your mind you still expect a miracle.

Second voice: And the doctors say I’m saying you are HIV positive. I was seated but I got a blackout. So the only thing remaining was to die.

Third voice: When I’m on duty, when the bell is rung nobody comes.

Fourth voice: For me it is an opportunity because the children will learn that my teacher is HIV positive and I know my teacher is not immoral. This child will grow up with that kind of attitude and it can reduce the stigma.

Fifth voice: After that we sat down, we talked and we agreed that we were going to live positive.

GM: That’s a trailer for a new DVD that’s just come out. It’s called Courage and Hope and it’s aimed at trying to address the stigma of HIV AIDS in Africa. One of the people responsible for it is Dr Michael Beasley and he is the Director of the Partnership for Child Development here on the St Mary’s campus, Imperial’s St Mary’s campus. So Michael tell us a bit more about the background to this DVD.

Dr Michael Beasley: The DVD has been made to address issues of stigma and discrimination against those affected by HIV and AIDS in Sub-Saharan Africa and particularly teachers. Teachers are critical members of their communities and often if a teacher becomes HIV positive it can be a source of great difficulty for them in their working career.

The aim of the DVD was to tell the stories of four Kenyan teachers to talk about the difficulties that were associated with their initial diagnosis and then subsequently what happened when they were able to access antiretroviral drugs to control the HIV with which they are infected. And so it’s called Courage and Hope, largely because the four teachers had to show amazing courage during that first stage when they were first diagnosed. And the hope comes from seeing what an extraordinary difference occurs when teachers are able to access the drugs that they need and can lead what to any of us would look like a completely normal life thereafter.

One of the things that’s most difficult in any society is enabling people to have the courage to go and get tested for HIV. Because stigma is so high there’s always that feeling of folk wanting to say it can’t be me. This can’t be happening to me. It couldn’t happen to me. And yet for many individuals that’s what is the case.

Voice: At the back of my mind I knew I was HIV positive. But of course even though you might have that at the back of your mind you still expect a miracle. When I saw the results it’s like the whole world just fell on me and I felt this is the end of it. So I stayed there for a few minutes composing myself and then I went to break the news to my wife. And I think when she saw me and she saw my eyes she knew that was the case.

GM: Presumably by going for teachers who are kind of leaders in their community, they are people who are respected enormously not just by the children they teach but all the people around them, by the teachers standing up and saying we’ve been tested, we are HIV positive, it may take away the stigma as far as other people are concerned and encourage other people to go and get themselves checked out?

MB: Certainly. And in most communities, almost countries rather I should say, there are many more teachers than health personnel, many more schools than clinics, and so teachers have a really strong role in many, many different communities across the continent.

GM: And it’s very timely as well, isn’t it, because this is going out in our December podcast, available from December 1, and December 1 itself is World AIDS Day so there’s obviously a lot of I suppose talk about HIV AIDS during the weeks that people are hopefully listening to this.

MB: That’s correct. December 1, World AIDS Day, the film itself is going to be launched at the International Conference on AIDS and STDs in Africa which will be held in Senegal from 3 to 7 December. Some of the teachers who’ve been in the film will be coming along to the launch. There’ll be members of the World Bank, of UN AIDS and senior members of ministries of education coming along to that launch and we hope it will really build on the momentum of World AIDS Day.

GM: Well, also here is Alice Woolnough and you are one of the executive producers of this DVD so just talk us through a little bit about what it involves.

Alice Woolnough: One of the things which we were very keen to do with the film was to discuss the stories of people living with HIV and to kind of probe the issues deeper. And one of the reasons for this is the importance of involving people living with HIV in the response to HIV so ensuring that they are part of the response, they’re part of the formation of policies, their issues are addressed and that they are an integral part of the work.

GM: So having made the DVD what happens now? Presumably you’re mailing them out to the schools? Having made it it’s very important that people watch them, isn’t it, so how do you make that happen?

AW: As Michael mentioned we are launching the film at ACASA and we’ve shipped thousands of copies of the DVD to ACASA and they will be given out to the many participants there. We will also mail it out and mail it out to some of our contacts. So one of the ways in which we will be distributing the film will be through the various different courses and workshops that we run and we facilitate at. And that will have the key participants who we’re looking to reach with this documentation. We will also be distributing it to ministries of education who will then be able to distribute it to their workforce, to their teacher training organisations in that area. So it should get a wide audience that way. In addition, we’re also looking to publically broadcast the film and I know that PBS have expressed an interest.

GM: This is in America is it?

AW: In America, yes. The interest is actually much broader than just Africa. And I know that we’ve had a lot of interest, for example, they’re interested in possibly screening it in the Caribbean where stigma is an even greater issue.

GM: And what do you think are the benefits of it being in the documentary form and an on location documentary? Because you could have very easily just set a camera up in one of the lecture theatres here and had lots of London based academics looking into the barrel of the cameral casting these messages down from on high and yet you’ve gone very much for the field approach, the location approach. How valuable do you think that is?

AW: I think when you’re talking about HIV there’s so much stigma and discrimination in relation to it that it’s really important to see those personal stories and to see people standing up and talking about their experience. And I think that really helps to get across the message that you’re HIV positive but you’re still a normal person. They’re still carrying on their lives as normal, they’re still teaching, and you can’t tell just by looking at them that they’re HIV positive.

GM: Finally, Michael, it’s notable that this comes from the Partnership for Child Development here at Imperial. The people taking part in the DVD are adults so how does this relate to HIV messages in children? I’m assuming it’s because these are teachers and therefore they’re in touch with their children in their region?

MB: What we’ve discovered is that HIV impacts right across education. So it affects a country’s ability to supply education. So to have enough teachers able to go into classrooms to deliver lessons to children. If teachers aren’t well and healthy then you get less and less teachers within the country. You might see the teacher to child ratio increasing. You see the quality of education decreasing.

And not keeping teachers well affects a countries’ abilities to achieve education for all and also the Millennium Development goals. So caring for teachers is a really, really important part of our work. But the other thing that’s really important with our work is recognising that even in the worst affected communities, so places like countries in Southern Africa where large proportions of the population are HIV positive, even in those countries school age children are very, very seldom infected with HIV. And so children are what are often referred to as the window of hope. If children at school can be given the skills and abilities and tools to remain clear of the HIV infection then there is the possibility that they can remain free of HIV for the rest of their lives and that prevention amongst school age children can be an extremely effective way of turning back this epidemic.

Voice: So I sat down with the virus and I put it there and I said now let us talk. Yes, let us talk now that you are here. So we talked with the virus and we made a memorandum with the virus in me and we actually agreed now our MOU was nobody should kill the other. Because I’m also in a position to kill the virus. If I commit suicide today the virus in my body will automatically die. I have to work until retirement so I told the virus that patient is for me not for those who stigmatise me. I have to live, work and get my pension. So together with the virus we agree quite well.

GM: One of the four teachers featured in the Courage and Hope DVD. I was also speaking there to Michael Beasley and Alice Woolnough at the Partnership for Child Development.

Michele Dougherty on the Cassini mission to Saturn and its moons

Well, finally this month remember this. It might sound like radio static but to be honest it’s actually one of the most remarkable sounds I’ve ever heard because it comes from another world. This is the audio that the Huygens probe beamed back to Earth in 2005 as it plunged through the atmosphere of Saturn’s moon Titan. Three years on and its mother probe Cassini is still going strong sending all kinds of data back from Saturn and its moons. One of the instruments on board is its magnetometer and in charge of that is Professor Michele Dougherty in our Physics Department. I called in to see Michele the other day and I first wanted to know what the highlights had been for her from the mission so far.

Professor Michele Dougherty: I think the most exciting time was when we first got there. Because in some ways it was almost the scariest time as well because what we needed to do is we needed to slow the spacecraft down so it could be captured by the gravity of Saturn and if we hadn’t done that properly we wouldn’t have had a spacecraft to be able to get our data from. So I think that was when we all held our breathe.

Once it went into orbit we could then breathe a bit better and then get on with actually looking at the data. I think the most exciting discovery that we made was actually made by data from the instrument that we built here. Because what we were able to discover is that one of the small moons called Enceladus has actually got an atmosphere on it. This was a real surprise because it’s one of the smallest moons. We thought it had cooled down. When the moons are first formed they’re hot and they’re giving off heat. We thought that since Enceladus was so small it had long cooled down. But what we found is that there’s out-gassing of water vapour from the South Pole at Enceladus and so that’s telling us that there’s some internal heat of some kind which is being given off. And one of the things we want to try and understand is why such a small moon has still got heat in its interior, is probably the best way to describe it.

GM: Because we think some of the atmosphere is from volcanoes and that kind of thing.

MD: At Jupiter there’s a moon called Io that has got volcanoes on the surface. At Enceladus it’s not volcanic activity but it’s almost like cracks are forming on the surface and the heat from the interior is forcing the water ice to become water and so you have essentially vapour plumes of water vapour coming off from the South Pole. The interesting thing is it’s focused just at the South Pole and so there’s something different happening in the interior towards the south than is happening in the rest of the moon. And so we really don’t understand it and so of course we want to go back. We’ve had lots more close fly-bys of Enceladus. In fact a couple of weeks ago we flew 25 kilometres above the surface and so we essentially flew through this vapour plume and we were able to take observations of what’s actually in the plume.

GM: And that’s where your experiment came in then? So you have this magnetometer and I suppose as the name suggests it looks at changes in the magnetic field and so on. Did that give you any insight when you embarked on this very close fly-by recently?

MD: Well, it was in fact our observations on a distant fly-by which persuaded the project to go much closer. If you have a body that has an atmosphere then the magnetic field lines in the vicinity of that atmosphere behave in a particular way. And on a distant fly-by of Enceladus what we found was that the magnetic field lines were being draped around the moon in a way that you would expect if the moon had an atmosphere. And so what we did is we went to the project and we said we think we’re seeing an atmosphere, because none of the other instruments had seen anything, we’d like you to do close. And that’s not an easy thing to do because while Cassini was on its way to Saturn we spent that six year period planning all the observations that we were going to make.

We knew over a four year timeframe exactly what we were going to do. And then we turned around and said to the project, hey, we want you to change it slightly. We want to go closer so we can see what’s going on. And so it took a bit of persuasion and I must confess I didn’t sleep very well for a couple of nights before that close fly-by. Because if we’d have flown past and seen nothing it would have been rather embarrassing.

But in fact what we found was that there was this atmosphere but it was focused at the South Pole and the other instruments on board found cracks on the surface. They found heat coming out from the surface and then they found water vapour plumes coming off as well. So it essentially confirmed the observations. And so although I didn’t sleep very well I was very relieved that I’d actually gone through it and persuaded the project to do it. And in fact not only is there water but some of the instruments have found organics on the surface. And organics are building blocks of life and so planetary scientists in general are very excited about Enceladus now. Because one of the building blocks of why people want to go out into space and find out new things is to see whether there is life somewhere else and you need water, you need heat and you need organic compounds and we’ve got all three of those on Enceladus.

GM: Where are we at, at the moment? What is Cassini doing at this particular point in time?

MD: We had a very recent fly-by past Enceladus a couple of weeks ago, that was the really close one. We’re orbiting past some of the other moons. But what we’re trying to do is we’re trying to change the area which we’re seeing. At the beginning of the four year tour that we had we focused mainly on the day side. What we’re now doing is moving out into the tail so essentially where it’s the middle of the night and we’re trying to get an idea about whether all the processes that we are seeing change depending on whether we’re in daytime, whether we’re in the night time. And as we get a better understanding of that we’ll be able to compare and contrast to the Earth as well.

GM: What are your hopes then for the future? What do you hope for from the magnetometer going forward?

MD: There’s another moon called Titan. Titan is the largest moon in the Solar System and it’s the only one that’s got a very large atmosphere. That was the moon that the Huygens probe travelled down through its atmosphere. And we’ve had numerous fly-bys of Titan. I think we’ve flown by Titan 47 times so far and we’re going to continue to do that in the extended mission. One of the reasons we’re interested in Titan is we think the atmosphere of Titan is very similar to what the atmosphere of the Earth was like when it first formed and so by understanding Titan’s atmosphere we can better understand how the Earth evolved and how life evolved on the Earth as well.

GM: Michele Dougherty of our Physics Department. And that wraps it up for this edition. And goodness me, that was the last podcast of 2008. There’s plenty more for you in January and indeed throughout 2009. But before I go just a quick mention for Oscar Buldum who wrote our theme tune and for the Imperial Press Office, who post this podcast, along with the Science Communication Group here. And if you like your radio with a technological flavour by all means come and find me on the BBC’s Digital Planet. Stick the programme name and my name, Gareth Mitchell, into any search engine and you can find that pretty easily. This edition has been produced by Helen Morant and so until January happy Christmas one and all and bye for now.