Optical clocks, healthy ageing, and fieldwork during pregnancy

Interviewer: Adam Levy

Welcome back to the Nature Podcast. This week in the show, a transportable optical clock, and refocusing age-related research…

Interviewer: Noah Baker

Plus: how field scientists manage pregnancy and motherhood. This is the Nature Podcast for the 15th of February 2018. I’m Noah Baker.

Interviewer: Adam Levy

And I’m Adam Levy.

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Interviewer: Noah Baker

Amy Dickman is a researcher from the University of Oxford.

Interviewee: Amy Dickman

I’m the Captain Senior Research Fellow in wildcat conservation.

Interviewer: Noah Baker

And she spends a lot of time in the field.

Interviewee: Amy Dickman

So, I work in Southern Tanzania in the Ruaha landscape. This is a hugely important place for large carnivores, particularly lions. It has about a tenth of the lions left in the world.

Interviewer: Noah Baker

Like many field scientists, her job comes with some features that you wouldn’t expect from the average nine to five.

Interviewee: Amy Dickman

I’ve had lions sleep on my tent. I’ve had elephants, you know, charge me and snakes all over the place. So there’s lots and lots of potential risk and it’s just different risk from being in the UK.

Interviewer: Noah Baker

All this travelling and, you know, dealing with wild animals, can be pretty tricky for a researcher and it’s made even trickier if they’re pregnant.

Interviewee: Amy Dickman

So the first pregnancy I was out there almost all the time. It was about month eight that I came back. With this pregnancy, obviously having then a nearly three year old at the time, I spent probably half that pregnancy in the field, coming and going.

Interviewer: Noah Baker

By any measure, this all sounds quite daunting but Amy’s primary concerns may not be quite what you’d expect for someone who spends so much of their life with lions.

Interviewee: Amy Dickman

I very much worried about how other people would see me when you have this transition to motherhood. Is it something that’s seen as a being bit weak? Is it going to compromise me as a scientist and how is it going to affect my career progression especially in that kind of lifestyles that I was living? I knew how to minimize attacks from lions. I didn’t know how to deal with this huge shift that was suddenly upon me.

Interviewer: Noah Baker

Of course, these concerns are not unique to field scientist, or for that matter, scientists. Here’s Joan Williams, a law professor from the University of California, Hastings. Much of her work has focused on gender equality.

Interviewee: Joan Williams

Motherhood has a huge impact on career progress for far too many people. It’s called the motherhood penalty or the maternal wall and it’s alive and well in science.

Interviewer: Noah Baker

In large part, Amy’s concerns about how this would affect her career were not really based on the specifics of her pregnancies but rather, what was expected of scientists in general. Joan explained.

Interviewee: Joan Williams

The idea is basically that if you’re a serious committed scientist, you’re always on. You’re an ideal worker who starts to work in early adulthood and works full force, full-time for 40 years straight and if you don’t do that you’re not a committed scientist.

Interviewer: Noah Baker

So, how did Amy approach it? She described how she first went to her superiors when she found out she was pregnant.

Interviewee: Amy Dickman

I had to write out a letter basically saying what my plans were and I said I’m going to take six to eight weeks off fully and then I’m going to be getting back into it and you won’t even notice the blip. And I’m going to be doing all the same things I was doing before because I really wanted to reinforce that feeling and that perception that nothing was going to change.

Interviewer: Noah Baker

But Amy didn’t get the reaction she was expecting.

Interviewee: Amy Dickman

And I got called in by the academic director of Pembroke College. I thought, you know, I shouldn’t have put eight weeks, I should have put six weeks, and when I sat down with him, he said look a baby is a perfect parasite. If you’re not exhausted, something is going wrong so you need to take the full six months off. You need to look at how we can support you to enable you to do this.

Interviewer: Noah Baker

His reasoning was simple.

Interviewee: Amy Dickman

He said a woman has maybe a 40 year career and even if you take out a year to be pregnant and have some maternity leave, and then you do that twice, we should be able to deal with a two year absence within a forty year career to retain women in science.

Interviewer: Noah Baker

Amy was supported by her institution but that didn’t mean that everyone’s attitude changed, especially given the nature of her fieldwork.

Interviewee: Amy Dickman

Some of those things were a bit unspoken. When you mention to people what you’re doing and they look at you and they see you’re heavily pregnant. There’s certainly that feeling that you get that should you be doing that, are you being selfish really? And that’s something that weighs on your mind. Are you being selfish? Am I putting my career above the welfare of my unborn child? It’s a huge responsibility.

Interviewer: Noah Baker

And that perceived risk wasn’t all she had to deal with.

Interviewee: Amy Dickman

Actually every one of those fears that I had have been realised to some extent. It has changed how much I am able or want to spend time in the field. It has changed, to some extent, maybe how some people perceive me. But actually what I hadn’t realise is that actually some of those changes can be very positive.

Interviewer: Noah Baker

Joan, who’s also a mother, agreed with Amy, even from her own personal experience.

Interviewee: Joan Williams

I think many mothers will tell you the same. You become laser efficient at organising teams because that’s what a family is, particularly if you have a paid care giver involved. It’s a team.

Interviewer: Noah Baker

While Amy did have a lot of positive experiences amongst the negative ones, Joan pointed out that there’s still a long way to go.

Interviewee: Joan Williams

The fact is we still have a tremendous distance to travel. It should be getting a lot easier for the simple reason that it makes absolutely no sense to spend a lot of money training women scientists and then to unceremoniously chase them out when they have children. And when you have the conjunction of pregnancy harassment and sexual harassment, it’s a pretty effective system for chasing women out of science.

Interviewer: Noah Baker

So what can women in Amy’s position do to alleviate these pressures? Amy’s advice is to talk about it.

Interviewee: Amy Dickman

And that was the most important thing for me. I think the first pregnancy I spent months and months of it worrying about these things by myself, keeping them to myself and ignoring the fact really that I was pregnant, trying to recognise as little as possible and I think that was a bad way of going forward. Yes it will change things but there are ways of managing those changes so that it can be positive for you. It’s not all going to be positive but it’s not going to be as bad as maybe people fear and we need to communicate much more openly about that so that people feel more secure.

Interviewer: Noah Baker

Joan’s solution to the problem was much broader.

Interviewee: Joan Williams

The solution is very simple. It’s to go back and change that definition of the ideal worker. I mean, the ideal scientist is sometimes pregnant.

Interviewer: Noah Baker

That was Joan Williams from the University of California, Hastings. Before her you heard Amy Dickman from the University of Oxford in the UK. To learn more about Amy’s work or find out more advice about how to manage pregnancy and a career in science, Nature’s Career’s section has just the feature for you. You can find that at Nature.com/news.

Interviewer: Adam Levy

Later in the show we’ll learn about efforts to counter age-related diseases. Up next though, we’re joined by Shamini Bundell for this week’s Research Highlights.

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Interviewer: Shamini Bundell

Snakes have been accidentally preserving plant pips by munching on mice according to researchers from the University of California, Berkeley. When rooting around in the stomachs of fifty rattle snake museum specimens, the team found almost one thousand seeds, several of which had begun to sprout. Usually, when seeds are digested by mice, they’re future as flora is nipped in the bud and they can’t germinate, however these sprouting seeds may not have been digested yet. Instead, the mice could have been storing them in their cheeks for later on. Since the seeds seem able to survive snake digestion, researchers suggest that snakes might actually be inadvertent gardeners, sowing seeds far and wide. Learn more in the Proceedings of the Royal Society B.

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Interviewer: Shamini Bundell

The heart of the heaviest element could be cloaked in an electron haze. Oganesson was first synthesized in 2002 and is considered a noble gas but it decays so quickly that measuring its properties is nigh on impossible. Physicists from Massey University, Auckland, have now calculated that this element’s electrons may be behaving in a rather unusual way. Electrons normally orbit an atom’s nucleus in distinct shells but the team predicts that the electrons flying furthest from Oganesson’s core swirl haphazardly like a gas. This would make Oganesson behave differently from the other noble gases. The ephemeral element could even be a solid at room temperature if it didn’t decay so quickly. This weighty research can be found in Physical Review Letters.

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Interviewer: Adam Levy

Imagine a time before you could easily get the time. Before the spread of pocket watches in the sixteenth century, you would have had to find a bulky, immovable clock to get an accurate measure of the hour. Today, many of us – myself included – don't bother with watches. After all, I've got my phone in my pocket. If I download the right app, I can even sync up with an atomic clock, so I never miss a second. It's almost like having my own transportable atomic clock: nifty! But what if I wanted a real transportable atomic clock or, to be precise, a transportable optical clock? Optical clocks are the next generation of atomic clocks and can be many times more accurate. Any clock needs an oscillation to count time. Instead of a pendulum, atomic clocks count oscillations of electrons bound to atoms. These atomic oscillations are incredibly quick: for an optical clock, almost 10 to the 15 – or one thousand million million – every second. And this allows for some astonishing accuracy in timekeeping. Well now a team has taken the incredible timekeeping of optical clocks out of the lab, and into the field. The team was using the clocks as a way of precisely measuring gravity, which can then give a precise measure of a location's height. I called up one of the researchers, Christian Lisdat to find out what clocks have to do with gravity in the first place.

Interviewee: Christian Lisdat

Well, it’s a little bit of a weird effect, I would say. Einstein told us that the time passes with different speed depending on how close you are to large mass, so where you are in gravity. So if we use this clock and we know it’s ticking with a different speed depending on where it is in gravity, we can use this information to determine how large the gravitational field is. And that’s what we do to measure height differences with clocks.

Interviewer: Adam Levy

People have done this before. People have used clocks to measure gravity before but you actually wanted to do it out in the field, right? Now, for me, not knowing anything about this I feel like, okay you take the clock and you put it there and job done but presumably it’s not quite that simple.

Interviewee: Christian Lisdat

No not really. First of all, to downsize a full lab of optical components into something you can fit into a car trailer and after doing this, having still something that is working with the high accuracy – or ideally the high accuracy you want to have. In addition, it’s not only that you need to have one clock but you observe how much the clock frequency changes. So you have to have two clocks to compare in different places, and a connection between them. So that’s a lot of infrastructure.

Interviewer: Adam Levy

So you mentioned there that it fits in a car trailer, so we’re not talking super portable?

Interviewee: Christian Lisdat

No, but I would say for this type of precision clock it’s a reasonable size because you can still bring it somewhere and you do not have to dismantle the whole apparatus.

Interviewer: Adam Levy

So you were hoping to precisely measure the difference in passing time between two clocks in different places and from this work out the height difference between the two. But the location you sent one of your clocks wasn't exactly the best place for delicate measurements?

Interviewee: Christian Lisdat

Well, it’s called the underground laboratory in Modane which is more or less a cave in the middle of the mountain connected to a car tunnel and we had interesting conditions like there was a tunnel to be constructed which was constructed by explosives. People had to leave the lab to go to shelter in case of ceilings falling down and things like that. So it’s not exactly what you would call quiet and nice.

Interviewer: Adam Levy

Now other techniques have actually directly measured the gravitational pull at this location before, and have been able to determine the height that way. But what answer were you able to get using optical clocks?

Interviewee: Christian Lisdat

The height difference or potential difference we measured matched exactly the value we got from our colleagues. Of course, you always hope it works better. We had a number of technical failures. Things work very nicely in the lab but if you shake everything and you put it in a temperature changing environment, you see where your real problems are.

Interviewer: Adam Levy

So how limited was the accuracy you were able to achieve with this experiment?

Interviewee: Christian Lisdat

Well we were in the order of a few ten metres from the clock side where people can tell us the height difference to a few centimetres so there’s still a big gap to be filled but we think from what we learned in the measurement campaign that we can come to a few ten centimetres in the very near future now.

Interviewer: Adam Levy

And what do you think the future potential of this is? Do you think this might become a common way for people to measure the gravitational field at different locations?

Interviewee: Christian Lisdat

I really think so. We can connect very distant points very precisely and it’s an important thing to have a stable height reference system across the world to monitor what’s happening with respect to the height system like sea level rise and stuff like that.

Interviewer: Adam Levy

That was Christian Lisdat who's based at the Physicalish Technisher Boonders-ahn-shtalt in Germany. Find his paper and a News & Views in Nature Physics: that's nature.com/nphys.

Interviewer: Noah Baker

Coming up in the News Chat, we’ll be hearing about about the US science agency taking steps against sexual harassment. But before we get to that, it’s time for you to sit back in your rocking chair, pop a crocheted blanket over your knees and enjoy a nice slice of apple pie as Shamini Bundell delves into the study of ageing…

Interviewer: Shamini Bundell

For most of human history an average person’s chance of reaching old age was quite low. Infectious diseases were a big killer. They were hard to fight and children were particularly vulnerable. In modern times, however, life expectancy has been consistently increasing across the globe. A big part of that is that more children are actually reaching adulthood but over the last century we’ve also managed to increase life expectancy for older people, with far more medical options for treating age related health conditions. So as life expectancy continues to creep up, can we all look forward to living longer and healthier lives?

Interviewee: Ilaria Bellantuono

The assumption has always been that if you lived longer you lived healthier and I think it’s only recently we realised that might actually not be true.

Interviewer: Shamini Bundell

This is Ilaria Bellantuono of the University of Sheffield.

Interviewee: Ilaria Bellantuono

If you were born in 2006 you were probably going to live three years less than those born in 2014 if you were a male in Europe but actually, your health span has not improved at all so it means that those three extra years that one would live are actually spent in disease. At the moment the average age that a woman spends with disease is 18 years and the men it’s 15 years. It’s quite a long time.

Interviewer: Shamini Bundell

Ilaria, along with 12 co-signatories is the author of a Comment piece out this week which argues that we should all be thinking less about life span and more about health span: how long humans are living healthily. Now, there’s been a lot of research into diseases that are associated with old age – things like osteoporosis, arthritis, type 2 diabetes or Alzheimer’s are all studied extensively but Ilaria feels that there’s a problem with the way these diseases are studied.

Interviewee: Ilaria Bellantuono

You may think that studying ageing and age related diseases go hand in hand but actually the two communities are very separate. People who study diseases don’t think much about ageing per se and people who study ageing are really interested in longevity.

Interviewer: Shamini Bundell

Until recently, Ilaria told me, the impact of ageing as a contributing factor to a disease has often been ignored. For example, take animal models of age related diseases.

Interviewee: Ilaria Bellantuono

You know, if you look at most of the literature they are using young mice and if you look at models of osteoporosis, if you are lucky they probably give them four to six months of age. So all of those mechanisms of ageing, they are not present if you look at a study on Alzheimer’s they will be focused on the plaque and the role that age plays in the formation of this plaque is completely disregarded.

Interviewer: Shamini Bundell

Even in human studies which generally do involve older patients, diseases are still often considered in isolation.

Interviewee: Ilaria Bellantuono

At the moment, the approach that is taken to these diseases is to study them one by one. Clinical trials, for example, are done in a population of patients that have only one disease. But if you look at people over 65, 60% of them have more than one disease and 20% have more than five, so it’s not really the common case.

Interviewer: Shamini Bundell

Treatments for diseases are often studied in isolation too, meaning that drugs may not be tested for effectiveness in situations where a patient is taking several at once. But Ilaria advocates a rather different approach. Instead of looking for treatments for specific age-related diseases, she suggests developing drugs which tackle ageing itself. Research suggests that ageing is a major risk factor for a number of diseases, so reducing the effects of ageing should reduce the risk of developing a whole host of conditions. This isn’t a replacement for trying to treat the diseases themselves directly but could be an effective way to treat or prevent multiple diseases with only a single drug or treatment.

Interviewee: Ilaria Bellantuono

Now we understand very well how ageing happens. You know, what are the underlying mechanisms? And we now also know how to manipulate those mechanisms with medicinal drugs or lifestyle interventions.

Interviewer: Shamini Bundell

And, drugs for targeting ageing do exist in animal models at least. One example is a class of compounds called geroprotectors which have been shown to ward off heart, muscle and immune problems in mice but there are problems with testing these in humans as Ilaria explains.

Interviewee: Ilaria Bellantuono

It’s the regulatory approval process. The major issues with the drug approach to age related disease particularly when you target ageing is that ageing, per se, is not a disease and therefore you can’t have approval for using this drug in patients if you just say I want to delay ageing. So you have to have a disease to do that. So, I think at the moment we are a little bit stuck.

Interviewer: Shamini Bundell

Ilaria’s comment article contains specific suggestions for how the research community and regulatory bodies could help overcome these problems and develop a framework to approve drugs targeting ageing. One suggestion is for the research community to agree on a definition of multi-morbidity when several diseases occur at the same time so that they can get approval to test drugs that target more than one condition. There are various other changes and improvements yet to be made but Ilaria is optimistic about the long term outcomes.

Interviewee: Ilaria Bellantuono

Oh the changes will be enormous. I do think that there will be a real shift in the way we treat older people. That’s personally what I want to see before I retire.

Interviewer: Noah Baker

That was Ilaria Bellantuono of the University of Sheffield talking to Shamini Bundell. Ilaria’s Comment article can be found at nature.com/news.

Interviewer: Adam Levy

Time now, as ever, for this week’s News Chat, and I’m joined in the studio by Nature News Editor, Nisha Gaind. Hi Nisha.

Interviewee: Nisha Gaind

Hi Adam.

Interviewer: Adam Levy

Now, first up: combatting sexual harassment remains high on the agenda not just for science but certainly including science and now a US science agency is taking steps to try and follow up on accusations of sexual harassment.

Interviewee: Nisha Gaind

That’s right. So now the National Science Foundation in the United States which is one of their biggest grant giving agencies has made a policy which says any institution that is taking money from the NSF will have to report when a researcher there has been found to violate sexual harassment policies.

Interviewer: Adam Levy

How does this differ from what’s being done elsewhere?

Interviewee: Nisha Gaind

Well, so far it’s quite rare among US Federal research agencies to have this sort of policy. They don’t tend to make their grant recipients disclose when sexual harassment policies have been violated so it’s quite a big move.

Interviewer: Adam Levy

And in this case the investigation would still be done by the universities. Is that an issue at all that it would only be disclosed if these investigations find someone has indeed committed sexual harassment?

Interviewee: Nisha Gaind

So that’s right, the investigations will still probably be conducted by the universities. There is a concern among people who have assessed the policy that says what happens if a university starts an investigation but doesn’t finish it? And the policy doesn’t require universities to report unfinished investigations. So people are concerned that there might have been investigations that have started and identified problems but haven’t finished for whatever reason.

Interviewer: Adam Levy

So presumably the funding agency finding out about cases like this could in some cases lead to certain people’s funding being cut. I mean that could potentially have problems for the students of, say, a PI who’s accused of sexual harassment.

Interviewee: Nisha Gaind

That’s another thing that observers have said about the policy and it’s in fact an argument for possibly routing funding directly to students or postdocs in a lab instead of giving it to PIs.

Interviewer: Adam Levy

Now back across the pond to the UK. Universities here are struggling to stop impact factor abuse.

Interviewee: Nisha Gaind

Yeah, so we’ve got a story this week which was based on a meeting last week about the misuse of research metrics and that refers to instances when grant panels or hiring panels or promotion panels are looking at scientists for either promotions or awarding them grants and instead of looking at the content and the value of their research, they’re actually looking at the impact factors of the journals that the researchers have published in. And that makes scientists angry. They want the value of their research to be assessed rather than the journal in which they’re published.

Interviewer: Adam Levy

Isn’t that quite a laborious thing to do to just go through each paper and then say, oh here’s how great this paper is?

Interviewee: Nisha Gaind

It definitely is and that’s probably one of the main reasons that this culture of using research metrics as proxy indicators has emerged because it is a time saving thing. It means that you don’t have to necessarily read the whole of four research papers or whatever has been submitted by somebody who’s up for promotion but it does have downsides and this is now what the research community is trying to address.

Interviewer: Adam Levy

And there has actually been a Declaration on Research Assessment, or DORA, that universities have been encouraged to sign up to but according to our story, not many actually have.

Interviewee: Nisha Gaind

So, in 2012, something called the Declaration on Research Assessment, or DORA, was created and it aimed to really eliminate the misuse of these sorts of metrics but what we’ve found now in a survey that was conducted in Britain is that not many universities in the United Kingdom have actually signed up and that’s a worry.

Interviewer: Adam Levy

Is this a UK specific problem or is it similar in institutions around the world?

Interviewee: Nisha Giand

It’s absolutely not a UK specific problem. It’s a problem all over the world and in fact in countries like China, often institutions give researchers bonuses on the basis of where they publish their research, if they publish it in high impact journals. Now that’s exactly the type of behaviour that things like DORA aim to root out and as we say in our story, the people who are in charge of DORA really, really hope that researchers around the world, institutions around the world are now paying attention to DORA. It just so happens that we have data from a survey in the United Kingdom that really shows us in granular detail what’s going on in one country.

Interviewer: Adam Levy

Now it makes a lot of sense to avoid something like the impact factor which is a very blunt tool but in terms of what should be done, surely that depends on the University, on the subject, many different factors.

Interviewee: Nisha Gaind

That’s exactly right and there was a meeting last week in London where people who are interested in this topic came together to discuss what best practises would be and most people advocate the use of research metrics responsibly alongside traditional academic judgement and also really put emphasis on using them in a sensible way for the discipline that they’re dealing with. So, social sciences and humanities publish differently, cite differently, and that means that using certain types of research metrics badly disadvantages them compared to other types of sciences.

Interviewer: Adam Levy

Yeah, I know in social science, for example, publishing a book is the best thing you can do whereas for me as a physicist it was virtually unheard of.

Interviewee: Nisha Gaind

Exactly, yeah, so, monographs and so on are very important in some subjects and publishing in other more mainstream journals is more common in others.

Interviewer: Adam Levy

Thank you Nisha. For more on the latest science news, head over to Nature.com/news.

Interviewer: Noah Baker

And that’s it for this week’s show. Don’t forget to follow the podcast on Twitter @NaturePodcast or send us an email: podcast@nature.com.

Interviewer: Adam Levy

Stay tuned for next week where we’ll be taking a look at some youthful research. I’m Adam Levy.

Interviewer: Noah Baker

And I’m Noah Baker. Thanks for listening and see you next time.