Features

Cutting-edge scientific study of gold coins from different moments of the Roman Empire has revealed a thriving economy in the periods when the coins were minted.

Researchers from the University of Oxford and the University of Warwick brought three Roman coins for analysis by the Science and Technology Facilities Council’s ISIS Neutron and Muon Source. Each coin was from the reign of a different Roman emperor: one from Hadrian (2^nd century AD), one from Tiberius (early 1^st century AD) and one from Julian II (4^th century AD).

When high-value artefacts need to be analysed, researchers are generally required to employ non-destructive techniques. The aim in this case was to see if the coins had been surface enriched – or secretly mixed with other metals. By doing this, the team could deduce a number of things, including the levels of economic stability.

The results from the surface level analyses of these coins suggested that they were very high purity gold...We know the Romans deliberately surfaced enriched their silver coins to ‘hide’ the fact there was a lot of copper in them, so it is plausible something similar happened to the gold

Dr George Green

Lead author, Dr George Green, Leverhulme Trust Early Career Fellow and Lavery-Shuffrey Early Career Fellow in Roman Art and Archaeology at the University of Oxford, says, ‘The results from the surface level analyses of these coins suggested that they were very high purity gold. However, these measurements were from the first few fractions of millimetres of the coins. There was a very reasonable ‘what if’ of ‘what if they’re actually made of something different beneath the surface?’ We know that the Romans deliberately surfaced enriched their silver coins to ‘hide’ the fact there was a lot of copper in them, so it is plausible something similar happened to the gold.

‘Our work at ISIS enabled us to sample the very centre of these coins totally non-destructively and conclusively show that the high purity seen on the surface was representative of the composition of the ‘core’ of the coin. At a basic level, it is further testament to the economic health of the Roman Empire, but these conclusions are also useful for researchers who need to employ non- or negligibly-destructive techniques on the surfaces of Roman gold coins. Now they can be confident the surface is representative of the bulk of these objects.’  

Our work at ISIS...conclusively shows  the high purity on the surface was representative of the ‘core’ 

To measure the purity of the gold coins they used muonic X-ray emission spectroscopy, a totally non-destructive analytical process that involves firing negative muons at the artefact. The muons are then captured by the atoms within the coins, which then emit a ‘fingerprint’ of muonic X-rays that are unique to the chemical element they came from.

Using this technique allows scientists to probe deeper into the elemental make-up of the historical artefacts than possible with other methods, while being entirely non-destructive.

Muonic X-ray emission spectroscopy also does not require the object to be cleaned before analysis, reducing the workload placed on cultural heritage institutions. Cleaning some artefacts can actually lead them to become damaged, so this technique is particularly useful for analysing objects still covered in a layer of mud or soil – such as those salvaged from shipwrecks.

These results highlight the potential of this technique within the field of cultural heritage. It is a non-destructive technique...making it a perfect tool for those working on museum collections

Dr Adrian Hillier

Dr Adrian Hillier, lead instrument scientist at ISIS and the muon group leader, says, ‘These results highlight the potential of this technique within the field of cultural heritage. It is a non-destructive technique that can sample deep beneath the surface of archaeological objects. It requires no sample preparation and does not leave the artefact radioactive, making it a perfect tool for those working on museum collections.

‘Beyond working out the sub-surface purity of an object it could: determine the depth of any corrosion on an object; identify chemical changes within the artefact caused by unique manufacturing processes; or reveal that an object we thought was made of one thing is actually a forgery made of another – all without causing any damage.’

The RIKEN-RAL muon beamlines at the ISIS Neutron and Muon source was used as they could produce muons with a high enough momentum to penetrate deep beneath the surface of the artefact being studied. The muons are created by bombarding a carbon target with high energy protons, this causes the creation of pions which are extracted and then decay into muons. These muons have a range of different momenta; the muons with lower momentum are used to analyse the surface of the artefact and the high momentum muons pass deeper into the artefact obtaining data from its core.

See the journal article.

The year is 1934, and in a laboratory hidden in the basement of the Oxford University Museum of Natural History, a young woman peers at the clear crystals handed to her by the Waynflete Professor of Chemistry at Oxford University. The crystals are made of the peptide hormone insulin, which has been familiar to endocrinologists since 1921. But its intricate structure is still a mystery.

Its importance, however, was known even before insulin was actually discovered – the name ‘insulin’ was first used by the British physiologist Sir Edward Sharpey-Schafer in 1916, for a hypothetical molecule produced by the pancreatic islets that controls glucose metabolism.

Insulin stopped being hypothetical in 1921, when the Canadian physiologists Frederick Banting and Charles Herbert Best, working in the laboratory of J.J.R. Macleod, isolated insulin from a dog’s pancreas.

On a cold January just a few months later, Leonard Thompson, a 14 year old boy with diabetes, became the first person ever to receive an injection of insulin. Despite a serious allergic reaction, the insulin treatment worked, with usually high levels of blood and urine sugars seen in diabetes dropping to normal – Leonard lived for another 13 years.

'Before the discovery of insulin, there really wasn’t much you could do for people who had diabetes’, said Katharine Owen, Associate Professor of Diabetes and diabetes consultant physician. 'It really was a terrible diagnosis.'

100 years after the discovery of insulin made diabetes a treatable illness, it continues to be an active subject of study for scientists, including at Oxford. Endocrine research at the University has long roots, and it was here, in 1934, that the Nobel prize-winning physiologist Dorothy Hodgkin took the first X-ray crystallography photos of an insulin crystal, in her basement laboratory at the Museum of Natural History.

But while insulin’s intricate structure and its utility in treating diabetes (known since 1922) continued to fascinate Professor Hodgkin, it wasn’t until 1969 that she and her team were able to decode the structure of insulin –when she first started studying insulin, X-ray crystallography and computing techniques were simply not advanced enough to untangle the complex structure of insulin. It took 35 years of collaborative work at Oxford and beyond before these techniques were up to the task of understanding insulin.

On the face of it, insulin is simple – it’s a short chain of amino acids, produced by beta cells of the pancreatic islets, and it spurs the liver, fat and skeletal muscle cells to absorb glucose from the blood stream. But decreased or absent insulin activity, as well as insensitivity to insulin results in diabetes, a disease that affects 422 million people across the world.

A microscopy image showing mouse islet cells: the purple blobs are insulin-producing beta cells (credit: Dr Quan Zhang, OCDEM)

Understanding the structure of insulin not only made the mass production of insulin possible, allowing many more people to be treated – it also allowed other researchers to alter the structure of insulin, to create even better treatment options for patients. Insulin was the first protein to be chemically synthesised and produced by DNA recombinant technology, and it is on the World Health Organisation’s list of the medications needed in a basic health system.

But 100 years on, only about half of people requiring insulin actually have access to it. Within the UK, compared to white cohorts, children and young people with type 1 diabetes from minority ethnic communities are more likely to have higher indices of uncontrolled blood sugar, and were less likely to use insulin pumps or real-time, continuous blood sugar monitoring.

'These interventions have been really transformative in how we treat patients with diabetes', said Professor Owen. 'It is important that we try and get these treatments to all patients.'

A DIY movement

Professor Owen has seen the insulin treatment for diabetes transformed over the course of her 20 year career. 'Initially, the insulin treatments we gave didn’t allow patients much flexibility – patients had to eat meals with set amounts of carbohydrates, to match the insulin dose than clinicians gave them,' she said.

'But now, there are short and long-acting varieties of insulin, and patients can titrate the amount and type of insulin they take to fit in with life, mimicking a natural physiological response much more closely.'

This change has been driven by greater understanding of how insulin works, as well as technological advances such as insulin pumps (a small, body-worn electronic device that delivers insulin) and continuous glucose monitors (which continuously monitor blood sugar levels, and can easily send this information to a device like a smartphone). Enterprising diabetes patient communities have taken these technologies a step further – the #WeAreNotWaiting diabetes DIY movement developed a community-developed, open source algorithm that allows insulin pumps to use the information from continuous glucose monitors to dispense the appropriate amount of insulin, a closed loop which comes close to mimicking how insulin control works normally.

Professor Owen hopes that researchers will continue to refine this closed loop technology, and over 50 years after the structure of insulin was decoded at its Natural History Museum, Oxford University continues to be a hotbed of insulin and diabetes research: the University works closely with Novo Nordisk, the healthcare company which first started producing insulin in 1922, months after it was first used in a patient. Professor Chas Bountra, the Oxford University Pro-Vice-Chancellor for Innovation, says: 'Our partnership with Novo Nordisk has enabled us to accelerate game changing research through sharing valuable resources and knowledge exchange. This ultimately leads to people with diabetes benefiting sooner from resulting medical innovations.'

The Novo Nordisk Research Centre Oxford aims to identify game-changing therapies for patients with type 2 diabetes and cardiometabolic diseases, and Professor Bill Haynes, VP and Site Head of the Novo Nordisk Research Centre Oxford explains its mission: 'These projects involve innovative in vitro and in silico approaches to gain a deeper understanding of the mechanisms involved. Using cutting edge methodologies and collaborating in this way gives us the best chance of finding novel therapies for patients with diabetes.'

Similarly, the Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM) combines clinical care, research and education in its building at the Churchill Hospital, while the Diabetes Trial Unit specialised in performing local, national and multinational clinical trials to treat and manage diabetes.

Predicting the future

A major theme of recent work has been to identify and treat worsening conditions even before they happen – work led by OCDEM’s Professor Rury Holman suggests that clinicians might be able to predict diabetes-associated heart failure in newly diagnosed type 2 diabetes patients with a simple blood test. Another major project from OCDEM’s Dr Rustam Rea aims to develop a tool to predict which people with diabetes are at risk of low blood sugar levels when they are admitted to hospital.

In contrast to type 2 diabetes, which is caused by the body becoming increasingly insensitive to insulin even though it is still being secreted, type 1 diabetes is caused by the insulin-producing beta cells being destroyed, because of an auto-immune reaction.

But here too, Oxford researchers hope to enable clinicians to act early – Professors John Andrew Todd and Linda Wicker are currently trialing therapy using a new drug to compensate for this autoimmune reaction. Professor Todd said ‘Our hope is the results will help to implement a therapy for children and young adults who have signs of autoimmunity but are not yet diagnosed with the disease and thus prevent progression of this serious disorder, which affects one in 400 children per year.’

In September this year, Professor Todd was awarded the 2021 EASD-Novo Nordisk Foundation Prize for Excellence, for his decades of effort to understand, prevent and combat type 1 diabetes, some of which may ultimately make insulin redundant as a treatment.

‘The really remarkable thing is that 100 after the discovery of insulin, the fundamental treatment for diabetes hasn’t changed – doctors gave diabetic patients insulin in 1922, and we still give essentially the same treatment in 2021,’ said Professor Owen. 'But this new line of work raises the possibility of immunotherapy for at least some types of diabetes, which means we’ll finally have treatments other than insulin to offer.'

'I’m really optimistic about the future of treatment for diabetes, especially type 1 diabetes,' she added. 'Instead of figuring out better ways of giving insulin, we’re finally at the point where can start testing treatments that stop the disease getting worse, or even reverse it.'

The centenary of the discovery of insulin may therefore finally mark the turning point where insulin treatment for some of the diabetes patients who currently rely on it, may no longer be required.

• Without urgent action climate change will make it increasingly difficult to achieve a quality education – especially for disadvantaged girls and young women.  

Dr Catherine Porter, Young Lives Director, highlights an often overlooked impact of climate change on education

Young Lives’ unique longitudinal research reveals in stark terms how childhood exposure to climate shocks such as droughts and floods has an unequal impact on children’s development, affecting their nutrition and access to education. This impedes their learning progress, with poorest children most affected.

The climate crisis intersects with another crisis: interrupted education and widening inequalities during the COVID-19 pandemic. Urgent action and new research is required to help build resilience, enable 12 years of quality education for girls and boys, and help to prepare them to face vulnerabilities that previous generations have never had to deal with.

Extreme weather events are becoming more frequent with the poorest households hardest hit.

Extreme weather events are expected to rise in frequency and intensity, even if COP26 is successful in charting a path for limiting global warming to 1.5C. And we know low-income countries and younger generations will be hardest hit.

Since 2001, the Young Lives study, has followed the lives of 12,000 children in poor communities across Ethiopia, India (Andhra Pradesh and Telangana), Peru and Vietnam. We have built a unique body of data with huge potential for understanding the long-term impact of climate change on vulnerable children and young people. Our research shows that extreme weather events experienced during childhood are having a significantly unequal impact on the poorest and most vulnerable groups.

By the age of 15, many children in our study had already experienced at least one extreme weather event, such as drought or flooding. In Ethiopia, it was more than half of our sample (54%), 44% in India, and around a third in Vietnam (34%) and Peru (30%).

Children living in the very poorest households have been significantly more affected [by extreme weather events]. In Ethiopia, a startling 81% of children in our poorest households experienced at least one extreme weather event, compared to only 22% in the least poor households

And children living in the very poorest households have been significantly more affected; in Ethiopia, a startling 81% of children in our poorest households had experienced at least one extreme weather event, compared to only 22% in the least poor households. Similar trends can be seen in India (65% v 18%), Peru (63% v 12%) and Vietnam (50% v 17%).

Climate related shocks affecting children in their early life have negative impacts on their growing bodies and minds

When extreme weather events destroy crops or lead to higher food prices, vulnerable families struggle to maintain nutritious diets. Young Lives’ evidence shows that poor diets and child malnutrition can have severe long-term consequences, affecting physical growth, cognitive skills, and progress in school. Across all four countries, the children most likely to be under-nourished are in the poorest households, in rural areas, and often among minority groups.

The first 1000 days of life – from conception to age 2 - are critical for children’s health, development and life chances. In Ethiopia, our results show that early childhood stunting due to malnutrition has a significantly negative impact on important cognitive skills, such as vocabulary and basic mathematics, especially for children whose parents received little or no education.

Climate-crisis induced malnutrition can also be transmitted from one generation to the next

These early stage shocks have significant long-term consequences. In India, Young Lives data matched with historical rainfall data shows that droughts, flooding or cyclones experienced by a mother while she is pregnant can affect the future development of her child’s vocabulary by age five. Longer term effects on basic maths and socio-emotional skills such as self-esteem, self-efficacy and agency, manifest even into adolescence.  

In fact, analysis across all four study countries found that rainfall shocks and malnutrition experienced by adolescent girls even before they became pregnant can have a negative impact on future children’s height, again from infancy through to adolescence. Thus, climate-crisis induced malnutrition can also be transmitted from one generation to the next.

Poorer households are less resilient to financial hardships when climate shocks hit, which can increase the risk of interrupted education

Climate related shocks impact children and young people’s learning and education in different ways throughout their lives. In Vietnam, Young Lives evidence has shown reduced household income due to crop failures directly impact the amount of time children spend in school, particularly those from poorer households.

Families without access to affordable credit spend less on their children’s education during periods of crisis (for example, on school fees, learning materials or transportation) and are more likely to temporarily withdraw children from school, with less learning time available at home, leading to significant interruptions in education.

Without targeted action, the climate crisis is likely to further exacerbate inequalities, just as we have seen during the COVID-19 pandemic.

Girls and young women shoulder additional burdens of household work in times of crisis, amplifying their risk of dropping out of school

Food shortages and stresses on clean water supplies in times of drought and flooding also impact young people’s daily activities.  Additional household work, such as walking further to collect drinking water and firewood, or extra childcare responsibilities when children are unable to go to school, often fall on girls and young women, further reducing their own time to study and increasing their risk of dropping out of school altogether.

Hunger can affect a child’s ability to concentrate in the classroom and also increases the likelihood of missing school.

The unequal impact of COVID-19 on education highlights a critical need to adapt for the climate crisis

Despite improvements in access to both primary and secondary education over the last two decades, significant inequalities in learning outcomes remain between and across all four of our study countries, with children from poor households and in rural areas consistently disadvantaged.

Without targeted action, the climate crisis is likely to further exacerbate inequalities, just as we have seen during the COVID-19 pandemic. Our recent COVID-19 phone survey shows that interrupted education and a growing digital divide have increased the risk of children and young people from poor and rural backgrounds falling further behind, or never returning to education.

While our results show significant impacts on both girls and boys, the combined pressures of interrupted education, and the trend for households to resort to more traditional gender roles in times of stress, has meant vulnerable girls and young women, have been particularly affected. 

And those who have been most impacted by the pandemic are likely to be most vulnerable to the increasing effects of the climate crisis.

A call to action for more robust research and a broad approach to supporting vulnerable children achieve a quality education

Ensuring countries around the world honour commitments made during COP26 is critical if we are to prevent extreme global temperature rises, and enable the most disadvantaged communities to adapt to climate change in ways that safeguard children’s development and education – especially for girls and young women.

Enabling 12 years of quality education for all children (especially girls) in a changing climate requires a broad approach. Investing in teachers, schools and universities to improve the quality of education is pivotal.  But really to make a difference, we also need to address the persistent inequalities that hold children back and make them more vulnerable to external shocks.  Ensuring all children get the right start in life, including a sufficient and healthy diet is the foundation for future learning. Providing an enabling environment for all girls and boys to stay in school, with sufficient resources to study is also essential.

With increasing extreme weather events...we need much better understanding of how vulnerable communities actually experience and respond to climate related shocks 

With increasing extreme weather events continuing to impact the poorest families most, we need much better understanding of how vulnerable communities actually experience and respond to climate related shocks throughout their lives. 

We need to build evidence on:

• how climate related shocks, nutrition and learning interconnect – enabling more holistic programmes of support, including ‘shock-responsive’ social protection programmes to reach disadvantaged households in disaster prone regions, particularly for vulnerable infants and adolescent girls, aligned with early learning and school feeding programmes.
• how and why persistent inequalities continue to underpin the learning crisis in education – further longitudinal research is critical to understand both trends over time and the impacts of specific shocks, including climate related shocks; targeted investment in early years education and addressing the growing digital divide is critical to support poor and marginalised households, particularly in rural areas.
• the additional barriers to girls’ education in a changing climate – strengthening age and gender disaggregated data and evidence on the impact of climate change, and enabling specific action to help keep girls in school in times of stress, including practical measures to relieve burdens of household work and childcare responsibilities.

Mosquitoes are notoriously dangerous, responsible for over one billion cases of disease and around a million deaths each year. Tackling diseases such as malaria, yellow fever and dengue requires targeted control of their vector, the mosquito. This in turn relies upon detailed knowledge of the distribution, diversity and abundance of mosquitos in space and time.

The HumBug project has developed methods to detect and identify different species of mosquitoes using the acoustic signature (sound) of their flight tones, captured on an inexpensive smartphone.

The project recently openly released five years’ worth of research data of acoustic mosquito flight tones from 36 different species, representing over 20 hours of audio recordings that the team have expertly labelled and tagged precisely in time.

Co-Principal Investigator Professor Stephen Roberts says of the data release, 'Making our extensive dataset openly available will prove hugely beneficial to entomologists and mosquito domain experts. The scale of the data and associated algorithms is unique. We hope it will enable a better understanding of mosquito behaviour, distribution and help manage the threat they pose to humans.'

By using sound to identify different species, the Humbug system generates unprecedented levels of urgently needed high-quality, spatially accurate mosquito occurrence data without incurring any risk to those conducting the surveys. The recordings, along with their time and location, are uploaded by the app to a central server where mosquito sounds are detected and the species is identified using a suite of algorithms that distinguish species according to their acoustic signature.

The paper presents the first large-scale multi-species dataset of acoustic recordings of mosquitoes tracked continuously in free flight, at data collection sites include Kenya, Thailand and Tanzania, the UK, and the USA. It will be presented at the 35th Conference on Neural Information Processing Systems 2021 with an oral presentation in December 2021.

The HumBug Project is supported by a grant awarded through the 2014 UK Google Impact Challenge, the ORCHID project and the Bill & Melinda Gates Foundation. The project team includes researchers from the University of Oxford, Ifakara Health Institute in Tanzanis and the Kinshasa School of Public Health in the DRC.

Professor Brenda E Stevenson is an award-winning historian of race, slavery, gender, family, and conflict. She is also a mother and wife, and a Black woman who has dedicated her life to giving voice to the voiceless, by telling the stories of the enslaved and the oppressed. 

As she begins her tenure as Oxford University’s first Hillary Rodham Clinton Chair of Women’s History, she discusses her Inaugural lecture.

It is important to understand the unique positions that women have had in various cultures and societies and their experiences continue to be such a fascinating area of study. There is still so much more progression that needs to take place, and so many ways that we are not counted as equals at the table – and sometimes we are not counted at the table at all. 

‘In society, we move forward, but we also take a few steps back from time to time, and that is a painful dance’

It was through Susie Byrd’s contribution to an archive on enslaved peoples - particularly enslaved women - that I have been able to do much of my work. This is a woman that we don’t really know much about, but she was an incredible force. She was one of the first people to listen to enslaved women and men, and tell their stories, of what being enslaved meant for them. 

Through her work and that of others, we were able to turn a corner in how we looked at enslaved Black people as human beings, who have culture, ideas, family, and pain. People who suffer and love, and experience desire. It is not a matter of portraying people as perfect, but seeing them in their complex entirety, with the same kinds of strengths, weaknesses and abilities to soar and be defeated, as you and me.

Slavery is part of the human experience, or as some people would say, ‘the human stain’, and we really must understand that and what it is to be an enslaved person, to eradicate it. 

It’s not just something that took place in the US – or even the Caribbean, and it’s not just Black and white. It is an institution that has taken place since the beginning of what we call civilisation - the Greeks, Romans, Egyptians, Africa, Asia and the Americas, prior to European contact - and really every single society in the world. And it still exists today. 

‘It is not a matter of portraying people as perfect, but seeing them in their complex entirety, with the same kinds of strengths, weaknesses and abilities to soar and be defeated, as you and me.’

These cyclical difficulties and horrific inequalities that we live with, see, protest, are frightened by, and in turn, disgusted by, have been systematised over time, in a way that we can’t seem to break out of. I want my students to put themselves into the shoes of these girls and women – or not – because slaves were barefoot – and imagine, what was it like to be them? 

There are some unique challenges in teaching history of the enslaved. I think that slavery has been racialized and it can turn people off – particularly young people, because they either identify with that group, or they don’t. They get tired of their group constantly being the subject of negative attention and trauma, and the others feel they are made to feel guilty for things they played no part in. 

How people are marginalised across time captures peoples’ imagination when you make it relevant to them. You learn how people survive and overcome that – or they don’t. That is why I like to talk about how slavery has occurred across all societies, and still does.

Race matters, class matters and gender matters, and the ways in which any of us are treated in society, unfortunately, have a lot to do with those kinds of identities. 

The truth is that marginalised people (racially, economically, politically, culturally) are much more likely to be victimised in societies where those hierarchies have been established that say that they are not as important as other people. We have seen that happen in the US, UK and almost every place.

We also have to use what we get. We have to speak that truth but use the opportunities that we get to make positive change. In society, we do move forward, but we also sometimes take a few steps back, and that is a painful dance.

Being a Black female administrator in an academic space does come with its own unique challenges. A University is no different to any other place. The same biases and expectations exist as they do in any other industry, and people really see you in the same ways, positively and or negatively, that they see you anywhere and everywhere else. 

As my good friend and scholar, Deborah White says, black female scholars often are regarded at universities as ‘matter out of place’. 

‘Race matters, class matters and gender matters, and the ways in which any of us are treated in society, unfortunately, have a lot to do with those kinds of identities.’ 

As a female of colour in an institution not founded by people of colour, regardless of gender, people don’t expect to see you, for you to have a voice, or to be able to contribute or challenge anything. They don’t expect for you to be at the table - or even in the room. 

It is so easy to dismiss anyone who looks like me, whether my gender, race, class, generation or at the intersection of these traits, and to dismiss my presence as a tokenistic response to affirmative action, or inclusion, or a quota requirement. Anything that allows them to exclude you on that basis. But guess what? I don’t care anymore! 

From the time that I was in college some have viewed me as without merit. Those opinions no longer matter to me. I know that I have much to offer. For whatever reasons that I am where I am, I am thankful. 

As institutions work to be more inclusive, the little that they can do - at least initially - can appear tokenistic. But the key is to keep trying, that one hire or story, is one more person and idea than there was yesterday. There is a desire to push us into where we should have been a long time ago, but everything is a negotiation.