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Tag: University of Bristol

  • Warmer and murkier waters favour predators of guppies, study finds

    Warmer and murkier waters favour predators of guppies, study finds

    Newswise — Changes in water conditions interact to affect how Trinidadian guppies protect themselves from predators, scientists at the University of Bristol have discovered.

    Known stressors, such as increased temperature and reduced visibility, when combined, cause this fish to avoid a predator less, and importantly, form looser protective shoals.

    The findings, published today in the journal Proceedings of the Royal Society B, show guppies’ responses are more affected by the interaction of these stressors than if they acted independently.

    Natural habitats are facing mounting environmental challenges due to human activities such as land use changes, exploitation and climate change.

    Lead author Costanza Zanghi from Bristol’s School of Biological Sciences, explained: “Of all the possible environmental parameters that can stress a system, we decided to focus on increased temperature and water turbidity because previous research has shown that visual animals, like most fish, are greatly affected by them.

    “We know that warmer water affects fish swimming ability and hunger levels, and we also know that increased turbidity, such as haziness, can change how visual predators and prey interact with one another.

    “In this research we wanted to take these common stressors, which are known to be increasing in freshwater habitats globally, and see how visual fish would respond to one another when they are subject to these stressors at the same time.”

    “This is important and novel because sometimes, especially when multiple stressors modify similar behaviours in different ways, the overall outcome can be very different from what is shown by studies where only one stressor is tested. That’s because these stressors can interact in unpredictable ways.”

    The team observed the reciprocal responses between a predator and a shoal of prey under four treatments, optimal housing conditions (as a control), and in treatments where either temperature or cloudiness of water was increased. They were then tested with an interaction treatment where both temperature and turbidity were increased at the same time.

    This took several weeks of trials in the lab involving 36 predators and 288 prey fish. The animals were separated so they did not come to any harm.

    All the video recordings were then processed to obtain fine scale movements of all the fish so that the researchers could calculate the swimming speeds of all fish and how they related to one another: how close together the prey stayed and how far from the predator each prey tried to remain.

    Co-author Milly Munro, who joined the Ioannou Group specifically for this project said: “The opportunity to be involved in this study with the team was a great experience, and I am grateful having been awarded ASAB’s Undergraduate Scholarship funding. Designing and running the research alongside Costanza and the team was brilliant as my first academic research experience. I learnt a lot of valuable skills and insights into what it takes to produce and conduct a study of this kind, all I gained from this experience has truly aided me in current and future projects.”

    Zanghi said: “Incorporating multi-stressors in such experiments enhances the ecological relevance and applicability of findings.

    “In natural environments, organisms rarely experience isolated stressors but rather face complex combinations of stressors.

    “By investigating how organisms respond behaviourally to these realistic scenarios, the research becomes more applicable to conservation and management efforts.

    “It provides insights into how organisms may cope with and adapt to multiple stressors, aiding in the development of effective strategies for mitigating the negative impacts of environmental change.

    Now the team plan to test whether the decrease in anti-predator behaviour is as negative for the prey as it may seem and not a clever adaptation to allow prey fish to worry less about predators in an environment that keeps them safe. By using a wider range of predators, they will also investigate whether these changes can affect multiple species differently.

    Zanghi concluded: “This study is exciting as it introduces crucial ecological complexity in the context of predator-prey interactions.

    “By incorporating additional stressors and specifically testing the potential interactions between these factors, this study significantly contributes to our understanding of the dynamics between prey and their predators in a rapidly changing world.”

     

    Paper:

    Zanghi C, Munro M, Ioannou CC. 2023 ‘Temperature and turbidity interact synergistically to alter anti-predator behaviour in the Trinidadian guppy’ Proceedings of the Royal Society B 290: 20230961.

    University of Bristol

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  • Knowledge powerhouses urged to join pioneering Africa-led mission to level up global research and restore Africa’s rightful place

    Knowledge powerhouses urged to join pioneering Africa-led mission to level up global research and restore Africa’s rightful place

    Newswise — Global institutions are today being called on to back a bold, transformative plan for Africa to take its rightful role in research alliances, driving forward social justice, advancing science, and supercharging global scholarship.

    The ambitious charter, which is firmly Africa-centred, aims to redress entrenched power imbalances in global knowledge production. These historic disparities have fuelled a huge gap between universities and scholars in Europe, North America, and Australia, and their African counterparts. It is being co-created by Africa’s major higher education bodies and facilitated by the Perivoli Africa Research Centre (PARC) at the University of Bristol in partnership with the University of Cape Town (UCT) and the University of South Africa (UNISA).

    More than 400 Vice-Chancellors from universities across the world are invited to embark on this transformative journey at a special event on Wednesday, 5 July in Namibia where leaders will be championing excellence in African higher education at a continental conference hosted by the Association of African Universities.

    They, along with representatives from higher education, research funders, publishers, governments, and policy bodies, will be asked to sign up to a set of principles for policy reform and a step change in international cooperation. This new approach is set to rebalance and enrich the science and research ecosystem, which still systemically favours the Global North and disadvantages the Global South, perpetuating Western predominance.

    Despite forming 10% of the world adult population Central, East, Southern and West Africa contribute a tiny fraction (just 1.6% in 2018) of scientific publications globally. Compounding this underrepresentation, the majority of African research involves collaboration with richer countries. According to the United Nations Educational, Scientific, and Cultural Organisation (UNESCO), between 2017-2019 around 88% of scientific work in East and Central Africa, and 85% in Southern Africa, had international partners with the USA, UK, and France being the most common collaborators.

    No universities in Africa feature in the top 200 of the latest annual QS World University Rankings. Only five African institutions, four of which are in South Africa, make the top 500 and none outside of South Africa, Egypt, and Tunisia are in the top 1,000. Similarly, very few highly cited scholars are affiliated with African universities and, as also shown in the UNESCO Science Report 2021, a disproportionately small number of researchers and scientific publications in the world are African.

    Key goals of the charter include:

    * Creating a radically new approach to research collaboration which redresses deep-seated divides in the generation of scientific knowledge.

    * Championing this reformed equitable way of working as standard and best practice.

    * Introducing an Africa-centred framework setting out guiding principles and measures of success and accountability.

    Associate Professor Divine Fuh, Director of the Institute for Humanities in Africa (HUMA) at the University of Cape Town, said: “UCT’s Vision2030 emphasises the importance of centring Afrika as a framework for knowledge futures and social justice. The charter offers an opportunity for the global community to take seriously and resolve important critiques and constructive suggestions on how to build a better humanity, through truly equitable research collaborations.

    “The charter brings the global epistemological, ontological and human dignity projects together, building on an intersectionality of critiques (decolonial, feminist, indigenous, LGBTQIA++, amongst others), to offer humanity a unique opportunity to place collective research and a truly communal science at the core of advancing human dignity, world-making and futures creation.

    “Launching the charter is just the start of a long and exciting journey towards balancing the global science and research ecosystem. As a global space for convivial and Africa-centred inquiry, HUMA is proud to be associated with and co-leading this world-transforming initiative.”

    Professor Puleng Lenkabula, Principal and Vice Chancellor of the University of South Africa, said: “This charter effectively creates a platform for Africa and her people to redefine, redraw and reframe collaborations to reflect the spirit of mutual respect, shared vision and shared aspirations of participants: a true reflection of Africanism finding global expression.

    “This is a radical charter and moment in history where a broad range of African people get to have agency to determine their own futures at all levels. In this way, Africa’s agency will be fully recognized, reinforced and protected for achieving the envisioned Afrofutures.”

    Over the coming months charter signatories will together co-create and further develop a comprehensive plan to achieve core objectives of the Africa Charter for Transformative Research Collaborations.

    The Perivoli Africa Research Centre (PARC) demonstrates the University of Bristol’s commitment to championing transformation in interdisciplinary research partnerships with Africa, as well as its wider culture of alternative thought and spearheading social justice. By rebalancing the global science and research ecosystem, African scholars, institutions and knowledge will be able to claim their rightful place in international scientific endeavour and status.

    Funded by the Perivoli Foundation, since its inception in 2020 PARC has been modelling this ethos through open competitions for African researchers from all fields of study to ensure an Africa-led agenda and a focus on national or regional priorities.

    Professor Isabella Aboderin, Perivoli Chair in Africa Research and Partnerships at the University of Bristol, said: “The charter signifies an essential movement, which ultimately aims to rebalance the entire global research ecosystem. The end goal is unashamedly ambitious, but the initiative recognises Global North-Africa research collaborations as a vital and viable entry point to help achieve this comprehensive shift.

    “Our call to action is timely, as there is growing understanding across the world that this is not only crucial for social justice, but also for fostering the enhanced scholarship and science the world so urgently needs to address the many crises and challenges we face collectively.

    “The scale of our journey will be all-encompassing and at times complex, changing mindsets, shared norms, resourcing, and policies. But the core ethos is simple and clear: the Global North must cede influence and space so Africa can take the wheel.”

    Professor Agnes Nairn, Pro Vice-Chancellor (Global Engagement) University of Bristol, said: “We will tackle pressing global challenges including climate change, pandemics and poverty more effectively if Africa takes a more prominent role in global transdisciplinary research. We are proud to be associated with this Africa-centred charter that will make global scientific knowledge production not only more just but also so much more powerful.” 

    Ends

    Notes to editors

    Interviews and advance copies of the draft charter are available on request. Images of the event on 5 July will also be available on the day. Please contact Victoria Tagg, Media & PR Manager (Research), University of Bristol: [email protected]

    Video:

    Here is a short explainer video about the Charter: (1) Trailer 3 – YouTube

    Credit: telling.video

    Images:

    Image 1

    download: PARC_Charter_media_release_image_1.jpeg (bris.ac.uk)

    Caption: Image shows (top right) Professor Isabella Aboderin, PARC Director, University of Bristol, collaborating with international partner representatives and research associates at a Charter Consultation meeting held at the Association of African Universities (AAU) in Accra, Ghana, West Africa in January, 2023.

    Credit: AAU TV  

    Image 2

    download: PARC_Charter_media_release_image_2.png (bris.ac.uk)

    Caption: Image shows (left to right) Associate Professor Divine Fuh, HUMA Director,  University of Cape Town; Professor Evelyn Welch, Vice-Chancellor and President, University of Bristol; Professor Isabella Aboderin, PARC Director, University of Bristol, and Marie Staunton, Strategic Coherence of ODA-funded Research (SCOR) Board Chair, attending a Charter Consultation meeting with the All Party Parliamentary Groups for Africa (APPG-A) and for Universities at Portcullis House, UK Parliament, Westminster, London, in May 2023.

    Credit: Royal African Society and APPG-A

    Additional quotes:

    Professor Puleng Segalo, Chief Albert Luthuli Research Chair at the University of Africa, said: “This charter signifies a moment for Africa to assert its vision on how collaborations need to unfold and doing so recognising the power vested in the continent. We acknowledge that even though there’s been quite a lot of work done on equitable partnerships, most still focus mainly on the symptoms and not the core issues.

    “It is our hope that through this charter, there will be a shift in decision making and actioning of these decisions where power does not lie in the Global North (only) but within the continent itself – to strive towards intellectual and economic agency.”

    Professor Evelyn Welch, Vice-Chancellor and President of the University of Bristol, said: “It has been a privilege to work with colleagues across African universities to develop this charter, which will support a new dialogue and approach to research on some of the world’s most pressing problems and opportunities, from climate change to the impact of AI.”

    University of Bristol

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  • Long Covid not caused by COVID-19 immune inflammatory response, new research finds

    Long Covid not caused by COVID-19 immune inflammatory response, new research finds

    Newswise — Long Covid, which affects nearly two-million people in the UK1, is not caused by an immune inflammatory reaction to COVID-19, University of Bristol-led research finds.  Emerging data demonstrates that immune activation may persist for months after COVID-19.

    In this new study, published in eLife today [4 July], researchers wanted to find out whether persistent immune activation and ongoing inflammation response could be the underlying cause of long Covid.  

    To investigate this, the Bristol team collected and analysed immune responses in blood samples from 63 patients hospitalised with mild, moderate or severe COVID-19 at the start of the pandemic and before vaccines were available. The team then tested patients’ immune responses at three months and again at eight and 12 months post hospital admission. Of these patients, 79% (82%, 75%, and 86% of mild, moderate, and severe patients, respectively) reported at least one ongoing symptom with breathlessness and excessive fatigue being the most common.

    Dr Laura Rivino, Senior Lecturer in Bristol’s School of Cellular and Molecular Medicine and the study’s lead author, explained: “Long Covid occurs in one out of ten COVID-19 cases, but we still don’t understand what causes it.  Several theories proposed include whether it might be triggered by an inflammatory immune response towards the virus that is still persisting in our body, sending our immune system into overdrive or the reactivation of latent viruses such as human cytomegalovirus (CMV) and Epstein Barr virus (EBV).”

    The team found patients’ immune responses at three months with severe symptoms displayed significant dysfunction in their T-cell profiles indicating that inflammation may persist for months even after they have recovered from the virus. Reassuringly, results showed that even in severe cases inflammation in these patients resolved in time. At 12 months, both the immune profiles and inflammatory levels of patients with severe disease were similar to those of mild and moderate patients.

    Patients with severe COVID-19 were found to display a higher number of long Covid symptoms compared to mild and moderate patients. However, further analysis by the team revealed no direct association between long Covid symptoms and immune inflammatory responses, for the markers that were measured, in any of the patients after adjusting for age, sex and disease severity.

    Importantly, there was no rapid increase in immune cells targeting SARS-CoV-2 at three months, but T-cells targeting the persistent and dormant Cytomegalovirus (CMV) — a common virus that is usually harmless but can stay in your body for life once infected with it— did show an increase at low levels. This indicates that the prolonged T-cell activation observed at three months in severe patients may not be driven by SARS-CoV-2 but instead may be “bystander driven” i.e. driven by cytokines. 

    Dr Rivino added: “Our findings suggest that prolonged immune activation and long Covid may correlate independently with severe COVID-19. Larger studies should be conducted looking at both a larger number of patients, including if possible vaccinated and non-vaccinated COVID-19 patients, and measuring a larger range of markers and cytokines.  

    “Understanding whether inflammation and immune activation associate with long Covid would allow us to understand whether targeting these factors may be a useful therapy for this debilitating condition.”

    The study was supported by the Elizabeth Blackwell Institute (EBI) with funding from the University of Bristol’s alumni and friends and Southmead Hospital Charity.

    Paper

    ‘Prolonged T-cell activation and long COVID symptoms independently associate with severe COVID-19 at 3 months’ by Marianna Santopaolo, Michaela Gregorova, Laura Rivino et al. in eLife [open access]

    University of Bristol

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  • Gloss is less effective camouflage in beetles compared to matte, according to latest study

    Gloss is less effective camouflage in beetles compared to matte, according to latest study

    BYLINE: Laura Thomas

    Newswise — When combined with iridescent colouration, a matt target surface appearance confers greater survival benefits in beetles than a glossy surface, scientists at the University of Bristol have found.  

    The findings, published in Behavioural Ecology, suggest that iridescence provides camouflage independent of glossiness, which means that it is the colour of iridescent surfaces and its changeability, that is the most important aspect of iridescence in enabling camouflage.

    Iridescence is a type of structural colouration that produces bright, vibrant hues. These are often angle-dependent, meaning the observed colour appears to change depending on the viewing angle.

    Lead author Dylan Thomas from Bristol’s School of Biological Sciences, said: “This is somewhat surprising. Recent theories had suggested prey target gloss could be important in concealment, but our findings actually suggest the opposite to be true.

    “In other words, perhaps glossiness isn’t as important to camouflage as had previously been suggested.”

    The team produced artificial beetle targets and pinned these to trees in Leigh Woods in Bristol and observed how well they survived under predation by natural bird predators.

    Half were sprayed with a glossy fixative and half a matt fixative. They were fixed to ivy leaves, placing a mealworm between the target and the leaf, and secured against tree roots or trunks. The targets were checked at 24-hour intervals over a 96-hour period for signs of bird predation – if the mealworm had been eaten, the target was classed as having been predated.

    When collecting targets, they also selected the background leaves for analysis as a previous study had found that background gloss has a significant effect on target survival.

    Dylan explained: “Our results provide further evidence that iridescent colouration can provide effective camouflage.

    “They also support previous findings that background glossiness has a significant effect on target survival – when targets are on a glossy background, their survival is enhanced.”

    Now the team plan to further explore why so many beetle species are glossy, given it is detrimental to their survival when combined with iridescence.

    They will also look at why black targets seem to survive well (second behind iridescence), the effects of background gloss and how lighting conditions affect how iridescence and gloss are perceived.

    Dylan concluded: “Our findings contribute to a widening literature on camouflaging iridescence and help us to better understand the role this distinctive form of colouration can have in concealment.

    “Our findings have also opened many avenues for further research, many of which are important not just to iridescence as camouflage but to camouflage as a whole.”

     

    Paper:

    ‘Interactions between colour and gloss in iridescent camouflage’ by Dylan Thomas et al in Behavioural Ecology.

    University of Bristol

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  • Modern horses have lost their additional toes, scientists confirm

    Modern horses have lost their additional toes, scientists confirm

    BYLINE: Laura Thomas

    Newswise — The distant ancestors of modern horses had hooved toes instead of a single hoof, which vanished over time, according to researchers.

    The animals, such as the Eocene Hyracotherium, had feet like those of a modern tapir: four toes in front and three behind, each individually hooved with an underlying foot pad.

    In contrast, modern equids such as horses, asses, and zebras, have only a single toe, the left over original third toe on each foot, encased in a thick-walled keratinous hoof, with an underlying triangular frog on the sole that acts as a shock absorber. 

    An international team of scientists, from the UK, the US, and the Netherlands, analysed hoof prints and foot bones from modern horses and fossil records to discover what happened to the lost digits.

    Author Professor Christine Janis from the University of Bristol’s School of Earth Sciences explained: “The upper portions – the remains of the additional hand and foot bones – remain as ‘splint bones’ fused with the remaining central one, but where are the fingers and toes?”

    “In later fossil horses there were only three toes front and back. The extra toes, known as side toes, in these horses were smaller and shorter than in a tapir, and likely did not touch the ground under normal circumstances, but they may have provided support in exceptional situations, such as sliding or forceful impact.”

    In findings, published today in Royal Society Open Science, they confirm the older notion that these toes really have been completely lost in evolution, not somehow retained within the hoof, as proposed in another recent paper published in the same journal in 2018.

    Lead author Professor Alan Vincelette, of St. John’s Seminary, Camarillo, California pointed out: “Although it does seem that remainders of the proximal (upper portions) of the side digits have been retained in modern horses, as the earlier 2018 paper claimed, the distal (lower portions, or toes) have simply been lost.

    The 2018 paper proposed that in modern horses these side toes are retained within the hoof of the central toe, in part contributing to the frog – although there are no actual bones within the frog.

    This was partially based on an interpretation of the hoof prints of an extinct three-toed horse, Hipparion (not on the direct line to modern horses) from Laetoli in Tanzania 3.7 million years ago, the same site that yielded the famous foot prints of the hominid Australopithecus. These hoof prints apparently lacked a frog, and this added weight to the notion that the side toes of horses like Hipparion now contribute to the frog of modern horses.

    While not all hoof prints of modern horses with frogs record its presence, an undoubted frog can be seen in many hoof prints that are known to have been made by three-toed horses. These observations cast doubt on the notion that the frog of modern horse hooves formed out of the side toes of tridactyl equids.

    Author Professor Christine Janis from the University of Bristol’s School of Earth Sciences said: “While the notion that modern horses have retained all of their original toes as within-hoof remnants is a novel one, and so rather appealing, it can be shown to be incorrect.”

    Alan Vincelette added: “The frog of the horse’s hoof evolved independently of the side toes as a unique structure providing shock absorption and traction during locomotion.”

    The team also show that the feet of one-toed horses have a different shape from the main toe of the foot of three-toed horses, being round rather than oval, a difference that may be related to differences in weight distribution and/or ecological habitat.

     

    Paper:

    ‘Hipparion tracks and horses’ toes: the evolution of the equid single hoof’ by Alan Vincelette, Christine Janis et al. in Royal Society Open Science.

    University of Bristol

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  • Scientists discover critical factors that determine the survival of airborne viruses

    Scientists discover critical factors that determine the survival of airborne viruses

    Newswise — Critical insights into why airborne viruses lose their infectivity have been uncovered by scientists at the University of Bristol. The findings, published in the Journal of the Royal Society Interface today [21 June], reveal how cleaner air kills the virus significantly quicker and why opening a window may be more important than originally thought. The research could shape future mitigation strategies for new viruses.   

    In the first study to measure differences in airborne stability of different variants of SARS-CoV-2 in inhalable particles, researchers from Bristol’s School of Chemistry show that the virus has become less capable of surviving in the air as it has evolved from the original strain through to the ‘Delta’ variant.

    Dr Allen Haddrell, the study’s lead author and Senior Research Associate in Bristol’s School of Chemistry, explained: “Aerosol particles, exhaled when infected individuals breathe, speak or cough, can transmit viruses – but how and why viruses lose infectivity once they are circulating around in these airborne particles has been widely debated.”

    To conduct the research, the team used a next generation bioaerosol technology instrument that they developed called CELEBS (Controlled Electrodynamic Levitation and Extraction of Bioaerosols onto a Substrate), that allowed them to probe the survival of different SARS-CoV-2 variants in laboratory generated airborne particles that mimic exhaled aerosol. They examined how environmental factors, such as temperature and humidity, particle composition and the presence of acidic vapours such as nitric acid alter virus infectivity over a 40-minute period.

    Through manipulating the gaseous content of the air, the team confirmed that the aero-stability of the virus is controlled by the alkaline pH of the aerosol droplets containing the virus. Importantly, they describe how each of the SARS-CoV-2 variants has different stabilities while airborne, and that this stability is correlated with their sensitivities to alkaline pH conditions. 

    The high pH of exhaled SARS-CoV-2 virus droplets is likely a major driver of the loss of infectiousness, so the less acid in the air, the more alkaline the droplet, the faster the virus dies.  Opening a window may be more important than originally thought as fresh air with lower carbon dioxide, reduces acid content in the atmosphere and means the virus dies significantly quicker.

    Dr Haddrell added: “Our results indicate that the high pH of exhaled aerosol drives the loss of viral infectivity. So, any gas that affects aerosol pH may play a role in how long the virus remains infectious in the air. For example, bleach gives off acidic vapour that may increase SARS-CoV-2 stability in the aerosol phase. Conversely, ammonia which gives of alkaline vapour may have the opposite effect.”

    The findings provide valuable insights into why and how aerosolised viruses lose their infectivity, setting the stage for the design of new strategies to mitigate risk.

    Jonathan Reid, Director of Bristol Aerosol Research Centre and Professor of Physical Chemistry in the School of Chemistry at the University of Bristol, and one of the corresponding authors, said: “There are numerous factors that affect the transmission of airborne viruses, and these are often confounded with physical and environmental parameters that can affect viral longevity in the aerosol phase such as temperature, relative humidity, air movement and UV light.

    “Our findings broaden our understanding of how environmental factors affect airborne stability of SARS-CoV-2 and other viruses, which will help us design better safety and mitigation strategies to reduce disease transmission. We now intend to explore the role of pH further through studying the role that carbon dioxide has on the risk of SARS-CoV-2 transmission.”

    The research was funded by the Biotechnology and Biological Sciences Research Council (BBSRC), National Institute for Health and Care Research (NIHR)-UK Research and Innovation (UKRI) rapid COVID-19 call, Elizabeth Blackwell Institute (EBI), University of Bristol and the PROTECT COVID-19 National Core Study on transmission and environment, managed by the Health and Safety Executive (HSE).

    Paper

    ‘Differences in airborne stability of SARS-CoV-2 variants of concern is impacted by alkalinity of surrogates of respiratory aerosol’ by Allen Haddrell, Jonathan P. Reid et al. in the Journal of the Royal Society Interface

    University of Bristol

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  • Machine-learning method used for self-driving cars could improve lives of type-1 diabetes patients

    Machine-learning method used for self-driving cars could improve lives of type-1 diabetes patients

    BYLINE: Laura Thomas

    Newswise — The same type of machine learning methods used to pilot self-driving cars and beat top chess players  could help type-1 diabetes sufferers keep their blood glucose levels in a safe range.

    Scientists at the University of Bristol have shown that reinforcement learning, a type of machine learning in which a computer program learns to make decisions by trying different actions, significantly outperforms commercial blood glucose controllers in terms of safety and effectiveness. By using offline reinforcement learning, where the algorithm learns from patient records, the researchers improve on prior work, showing that good blood glucose control can be achieved by learning from the decisions of the patient rather than by trial and error.

    Type 1 diabetes is one of the most prevalent auto-immune conditions in the UK and is characterised by an insufficiency of the hormone insulin, which is responsible for blood glucose regulation.

    Many factors affect a person’s blood glucose and therefore it can be a challenging and burdensome task to select the correct insulin dose for a given scenario. Current artificial pancreas devices provide automated insulin dosing but are limited by their simplistic decision-making algorithms.

    However a new study, published today in the Journal of Biomedical Informatics, shows offline reinforcement learning could represent an important milestone of care for people living with the condition. The largest improvement was in children, who experienced an additional one-and-a-half hours in the target glucose range per day.

    Children represent a particularly important group as they are often unable to manage their diabetes without assistance and an improvement of this size would result in markedly better long-term health outcomes. 

    Lead author Harry Emerson from Bristol’s Department of Engineering Mathematics, explained:  “My research explores whether reinforcement learning could be used to develop safer and more effective insulin dosing strategies.

    “These machine learning driven algorithms have demonstrated superhuman performance in playing chess and piloting self-driving cars, and therefore could feasibly learn to perform highly personalised insulin dosing from pre-collected blood glucose data.

    “This particular piece of work focuses specifically on offline reinforcement learning, in which the algorithm learns to act by observing examples of good and bad blood glucose control.

    “Prior reinforcement learning methods in this area predominantly utilise a process of trial-and-error to identify good actions, which could expose a real-world patient to unsafe insulin doses.”

    Due to the high risk associated with incorrect insulin dosing, experiments were performed using the FDA-approved UVA/Padova simulator, which creates a suite of virtual patients to test type 1 diabetes control algorithms. State-of-the-art offline reinforcement learning algorithms were evaluated against one of the most widely used artificial pancreas control algorithms. This comparison was conducted across 30 virtual patients (adults, adolescents and children) and considered 7,000 days of data, with performance being evaluated in accordance with current clinical guidelines. The simulator was also extended to consider realistic implementation challenges, such as measurement errors, incorrect patient information and limited quantities of available data.

    This work provides a basis for continued reinforcement learning research in glucose control; demonstrating the potential of the approach to improve the health outcomes of people with type 1 diabetes, while highlighting the method’s shortcomings and areas of necessary future development. 

    The researchers’ ultimate goal is to deploy reinforcement learning in real-world artificial pancreas systems. These devices operate with limited patient oversight and consequently will require significant evidence of safety and effectiveness to achieve regulatory approval.

    Harry added: ”This research demonstrates machine learning’s potential to learn effective insulin dosing strategies from the pre-collected type 1 diabetes data. The explored method outperforms one of the most widely used commercial artificial pancreas algorithms and demonstrates an ability to leverage a person’s habits and schedule to respond more quickly to dangerous events.”

     

    Paper:

    ‘Offline Reinforcement Learning for Safer Blood Glucose Control in People with Type 1 Diabetes’ Harry Emerson et al in Journal of Biomedical Informatics.

    University of Bristol

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  • Ancient herbivore’s diet weakened teeth leading to eventual starvation, study suggests

    Ancient herbivore’s diet weakened teeth leading to eventual starvation, study suggests

    BYLINE: Laura Thomas

    Newswise — A team of researchers from the University of Bristol have shed light on the life of the ancient reptile Rhynchosaur, which walked the earth between 250-225 million years ago, before being replaced by the dinosaurs.

    Rhynchosaurs are a little-understood group of roughly sheep-sized ancient reptiles that thrived during the Triassic Period, a time of generally warm climates and tough vegetation.  

    In the new study, the researchers studied specimens found in Devon and used CT scanning to see how the teeth wore down as they fed, and how new teeth were added at the backs of the tooth rows as the animals grew in size.

    The findings, published today in Palaeontology, show that these early herbivores likely eventually starved to death in old age, the vegetation taking its toll on their teeth.

    “I first studied the rhynchosaurs years ago,” said team-leader Professor Mike Benton from Bristol’s School of Earth Sciences, “and I was amazed to find that in many cases they dominated their ecosystems. If you found one fossil, you found hundreds. They were the sheep or antelopes of their day, and yet they had specialized dental systems that were apparently adapted for dealing with masses of tough plant food.”

    Dr Rob Coram, who discovered the Devon fossils, said: “The fossils are rare, but occasionally individuals were entombed during river floods. This has made it possible to put together a series of jaw bones of rhynchosaurs that ranged in age from quite young, maybe even babies, through adults, and including one particularly old animal, a Triassic old-timer whose teeth had worn right down and probably struggled to get enough nutrition each day.”

    “Comparing the sequence of fossils through their lifetime, we could see that as the animals aged, the area of the jaws under wear at any time moved backwards relative to the front of the skull, bringing new teeth and new bone into wear,” said Thitiwoot Sethapanichsakul who studied the jaws as part of his MSc in Palaeobiology. “They were clearly eating really tough food such as ferns, that wore the teeth down to the bone of the jaw, meaning that they were basically chopping their meals by a mix of teeth and bone.”

    “Eventually, though, after a certain age – we’re not sure quite how many years – their growth slowed down and the area of wear was fixed and just got deeper and deeper,” added Dr Coram. “It’s like elephants today – they have a fixed number of teeth that come into use from the back, and after the age of seventy or so they’re on their last tooth, and then that’s that.

    “We don’t think the rhynchosaurs lived that long, but their plant food was so testing that their jaws simply wore out and presumably they eventually starved to death.”

    The rhynchosaurs were an important part of the ecosystems on land during the Triassic, when life was recovering from the world’s greatest mass extinction, at the end of the preceding Permian Period. These animals were part of this recovery and setting the scene for new types of ecologies when first dinosaurs, and later mammals became dominant, as the modern world was being slowly constructed.

    By comparing examples of earlier rhynchosaurs, such as those from Devon, with later-occurring examples from Scotland and Argentina, the team were also able to show how their dentitions evolved through time, and how their unique teeth enabled them to diversify twice, in the Middle and then in the Late Triassic. But in the end, climate change, and especially changes of available plants, seem to have enabled the dinosaurs to take over as the rhynchosaurs died out.

    The paper

    ‘Unique dentition of rhynchosaurs and their two-phase success as herbivores in the Triassic’ By Sethapanichsakul, T., Coram, R.A. and Benton, M.J. Palaeontology. Doi: 10.1111/pala.12654

    University of Bristol

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  • Most effective ways of foraging can attract predators, scientists find

    Most effective ways of foraging can attract predators, scientists find

    BYLINE: Laura Thomas

    Newswise — Animals using the most of efficient methods of searching for resources may well pay with their lives, scientists at the University of Bristol have discovered.

    The findings, published today in Behavioral Ecology, reveal why animals may not always use a searching strategy that maximises results.

    How animals move through their habitat, particularly in search for food, is a major question in biology, and has application in how animals will respond to environmental change.

    Numerous studies have demonstrated that a special kind of movement, known as Lévy motion, increases the ability to find resources because it includes long-distance moves between areas being searched, as well as periods of concentrated searching in one area. It has also been shown that a range of animals use this kind of movement.

    This study is the first to demonstrate a potential cost of Lévy motion in an experiment, showing prey using Lévy motion are targeted twice as often as prey using Brownian motion – the movement observed in molecules in a gas, and thus a baseline expectation.

    Professor Christos Ioannou from Bristol’s School of Biological Sciences explained: “We show that this is because the predators prefer to target prey that are moving with straighter paths of motion, possibly because this makes the future position of the prey more predictable.”

    Professor Ioannou and his team used a virtual prey approach. They developed a computer simulation of the prey which are identical in size, colour, speed etc but differ in how they turn.

    The video was then played to stickleback fish in a tank by projecting the video onto a translucent screen. This allowed the fish to see the prey, and for researchers to capture and record their choices.

    “By using an experimental design that presents virtual prey on a screen to real predators, we can control everything about the prey and isolate the variable we’re interested in – here, movement – while also using real animals,” continued Professor Ioannou.

    This study demonstrates that prey animals might not always use a searching strategy that maximises finding a resource because there might be costs that were, previous to the study, unknown. This might explain why some studies have found animals use different kinds of searches other than Lévy motion.

    He added: “Our study shows, for the first time, that animals using a common and very effective way of searching for resources may actually pay a cost of being more susceptible to predators.

    “Going forward, we want to look at whether the prey of sticklebacks show Levy or Brownian motion.

    “More broadly, our study predicts that prey animals should be less likely to demonstrate Lévy motion than apex predators.”

     

    Paper:

    ‘Virtual prey with Lévy motion are preferentially attacked by predatory fish’ by Christos Ioannou et al in Behavioral Ecology.

    University of Bristol

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  • Propellers are louder over ground, researchers find

    Propellers are louder over ground, researchers find

    BYLINE: Laura Thomas

    Newswise — The effects of the ground on propeller noise have been measured experimentally for the very first time by researchers in the Aeroacoustics research team at the University of Bristol.

    In findings, published in the Journal of Sound and Vibration, the team found clear differences in the noise characteristics of propellers when over ground, known as ‘Ground Effect’, compared to when operated normally. They noted an overall noise increase when measuring at angles above the ground, with hydrodynamic and acoustic interaction effects being a key factor to the overall noise trends.

    It is hoped this research, tested in the National Aeroacoustic Wind Tunnel facility, can inform strategies to reduce the noise of aircraft while taking off or landing, by either changing the design of the landing pads or by changing the design of proposed aircraft architectures.

    Lead author Liam Hanson explained: “In light of the need for greener aviation, there has been a push in the aviation industry to develop electrified aircraft.

    “There is a lot of potential benefits from electric aircraft which have been identified by a variety of companies worldwide, including all of the major aircraft manufacturers.”

    However, if urban air services such as on demand air taxis are to become a reality within city limits, engineers must tackle the issue of sound pollution, generated by propellers. 

    An important subset of electric aircraft being developed recently are for the purposes of Advanced Air Mobility (AAM). These aircraft can be broadly considered to fit in three different categories.

    The first is Electric Vertical Take-Off and Landing (eVTOL) aircraft which is focussing on Urban Air Mobility (UAM) applications such as air taxis, patient transfers, rooftop-to-rooftop trips within cities and airport transfers.

    The second category is Electric Conventional Take-Off and Landing (eCTOL) aircraft which is being developed for Regional Air Mobility (RAM). RAM focusses on cargo deliveries, short-range flights and passenger transfers from rural regions.

    The most commonly recognisable electric aircraft, small Unmanned Aircraft Systems (sUAS) or drones, can be considered the third category which focusses on videography, small package delivery and medical supply transfer.

    Each of these categories of electric aircraft often uses propellers or rotors to generate thrust to take off and land. Crucially, eVTOL aircraft are operating in urban areas with large populations and as a result the noise generated by the aircraft is critical to understand and reduce if UAM is to be possible.

    The propellers used by the aircraft are smaller than helicopters which have been in use for years, usually being far smaller in diameter and rotating at higher speeds. As a result the noise characteristics are very different to the existing knowledge, and so further research is required.

    While eVTOL and sUAS aircraft are taking off or landing from a rooftop or landing pad, the propellers are likely to experience Ground Effect, an aerodynamic phenomenon which changes the performance of propellers.

    This change in the propeller aerodynamics within Ground Effect changes the acoustic performance of the propellers and causes complex interactions.

    Liam said: “Until now, no literature existed for the problem of isolated propeller noise in ground effect.

    “Our research sought to answer for the first time what happens to propeller noise while it operates in Ground Effect and what are the key acoustic and aerodynamic interactions which are most important to understand.

    “For the first time we have comprehensively measured the noise of small-scale propellers during take-off and landing while interacting with the ground. It is clear we can expect louder eVTOL aircraft during take-off and landing if the complex interactions with the ground are not considered.”

    Based off their new understanding of propeller noise in Ground Effect, they are now conducting additional tests on different methods to potentially reduce the noise of the entire system.

    The research was sponsored by Embraer S.A. and the Horizon 2020 SilentProp project (agreement number 882842).

     

    Paper:

    ‘Experimental investigation of propeller noise in ground effect’ by Liam Hanson et al in Journal of Sound and Vibration.

     

    University of Bristol

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  • Research reveals majority of gig economy workers are earning below minimum wage

    Research reveals majority of gig economy workers are earning below minimum wage

    Newswise — As the cost of living continues to spiral, a new report shows more than half of gig economy workers in the UK are paid below the minimum wage.

    The first-of-its-kind study, led by the University of Bristol, found 52% of gig workers doing jobs ranging from data entry to food delivery were earning below the minimum wage. On average respondents were earning £8.97 per hour – around 15% below the current UK minimum wage, which rose to £10.42 this month.

    More than three-quarters (76%) of survey respondents also experienced work-related insecurity and anxiety.

    Lead author Dr Alex Wood, Senior Lecturer in Human Resource Management and Future of Work at the University of Bristol Business School, said: “The findings highlight that working in the UK gig economy often entails low pay, anxiety, and stress. As food, fuel and housing costs keep rising, this group of workers are especially vulnerable and need to be more adequately remunerated and better protected.”

    Equally concerning, more than a quarter (28%) felt they were risking their health or safety in doing gig work and a quarter (25%) experienced pain on the job.

    When asked what would improve their situation, basic rights such as minimum wage rates, holiday and sick pay, and protection against unfair dismissal were most wanted.

    Unions and platform councils (similar to works councils that exist in some European countries) to represent their needs and help influence how gig economy platforms operate and affect their working conditions also featured on their wish list. More than three-quarters of respondents believed the introduction of such bodies would bring immediate benefits.

    Dr Wood said: “A major factor contributing to low pay rates is that this work involves spending significant amounts of time waiting or looking for work while logged on to a platform. Not only is the work low paid, but it is also extremely insecure and risky.

    “The self-employed who are dependent on platforms to make a living are urgently in need of labour protections to shield them against the huge power asymmetries that exist in the sector. This clearly warrants the expansion of the current ‘worker’ status to protect them.”

    The study involved 510 UK gig economy workers who were surveyed last year. There was representation from across the sector, with around half being remote freelancers using platforms such as Upwork and Fiverr to pick up jobs ranging from data entry to website design. The other half comprised local drivers providing food delivery and taxi services via platforms including Deliveroo and Uber.

    More than just side hustles to earn extra cash, respondents spent on average 28 hours a week undertaking gig work, comprising 60% of their total earnings.

    Respondents overwhelmingly considered their work to be best described as self-employment and thought an extension of labour rights to include the self-employed would significantly improve their working lives.

    This was the first research to investigate what forms of voice gig workers want. The findings suggest strong support for European style co-determination whereby worker representatives are consulted on and approve changes that impact working conditions and employment. Works councils that exist in countries like Germany could therefore provide a model for platform councils and assemblies in the gig economy to facilitate workers having a say over the decisions which affect their ability to make a living.

    Brendan Burchell, Professor in Social Sciences at the University of Cambridge and co-author of the report, added: “Respondents strongly felt the creation of co-determination mechanisms would allow workers, and their representatives, to influence platform provider decisions which could instantly improve their working lives.

    “These policies include elected bodies of worker representatives approving all major platform changes that impact jobs and working conditions. Our findings emphasise the potential for trade union growth in this sector, with majorities being willing to join and even organise such bodies.”

    University of Bristol

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  • Robot fish makes splash with motion breakthrough

    Robot fish makes splash with motion breakthrough

    Newswise — A coil-powered robot fish designed by scientists at the University of Bristol could make underwater exploration more accessible.

    The robot fish was fitted with a twisted and coiled polymer (TCP) to drive it forward, a light-weight low cost device that relies on temperature change to generate movement, which also limits its speed.

    A TCP works by contracting like muscles when heated, converting the energy into mechanical motion. The TCP used in this work is warmed by Joule heating – the pass of current through an electrical conductor produces thermal energy and heats up the conductor. By minimising the distance between the TCP on one side of the robot fish and the spring on the other, this activates the fin at the rear, enabling the robot fish to reach new speeds. The undulating flapping of its rear fin was measured at a frequency of 2Hz, two waves per second. The frequency of the electric current is the same as the frequency of tail flap.  

    The findings, published at the 6th IEEE-RAS International Conference on Soft Robotics (RoboSoft 2023), provide a new route to raising the actuation – the action of causing a machine or device to operate – frequency of TCPs through thermomechanical design and shows the possibility of using TCPs at high frequency in aqueous environments.

    Lead author Tsam Lung You from Bristol’s Department of Engineering Mathematics said: “Twisted and coiled polymer (TCP) actuator is a promising novel actuator, exhibiting attractive properties of light weight, low-cost high energy density and simple fabrication process.

    “They can be made from very easily assessable materials such as a fishing line and they contract and provide linear actuation when heated up. However, because of the time needed for heat dissipation during the relaxation phase, this makes them slow.”

    By optimising the structural design of the TCP-spring antagonistic muscle pair and bringing their anchor points closer together, it allowed the posterior fin to swing at a larger angle for the same amount of TCP actuation.

    Although this requires greater force, TCP is a strong actuator with high work energy density, and is still able to drive the fin.

    Until now, TCPs have been mostly used for applications such as wearable devices and robotic hands. This work opens up more areas of application where TCP can be used, such as marine robots for underwater exploration and monitoring.

    Tsam Lung You added: “Our robotic fish swam at the fastest actuation frequency found in a real TCP application and also the highest locomotion speed of a TCP application so far.

    “This is really exciting as it opens up more opportunities of TCP application in different areas.”

    The team now plan to expand the scale and develop a knifefish-inspired TCP-driven ribbon fin robot that can swim agilely in water.

     

    Paper:

    ‘Robotic Fish driven by Twisted and Coiled Polymer Actuators at High Frequencies’ by Tsam Lung You et al at the 6th IEEE-RAS International Conference on Soft Robotics (RoboSoft 2023).

    University of Bristol

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  • Pioneering research sheds new light on the origins and composition of planet Mars

    Pioneering research sheds new light on the origins and composition of planet Mars

    Newswise — A new study has uncovered intriguing insights into the liquid core at the centre of Mars, furthering understanding of the planet’s formation and evolution.

    The research, led by the University of Bristol and published in the journal Proceedings of the National Academy of Sciences of the US, reveals the first-ever detections of sound waves travelling into the Martian core. Measurements from this acoustic energy, called seismic waves, indicate its liquid core is slightly denser and smaller than previously thought, and comprises a mixture of iron and numerous other elements.

    The findings are all the more remarkable, as the research mission was initially only scheduled to last for a little over one Mars year (two Earth years). Despite Martian storms hastening the accumulation of dust and reducing power to the NASA InSight Mars lander, NASA extended its stay, so geophysical data, including signals of marsquakes, continued to be gathered until the end of last year.

    Lead author Dr Jessica Irving, Senior Lecturer in Earth Sciences at the University of Bristol, said: “The extra mission time certainly paid off. We’ve made the very first observations of seismic waves travelling through the core of Mars. Two seismic signals, one from a very distant marsquake and one from a meteorite impact on the far side of the planet, have allowed us to probe the Martian core with seismic waves. We’ve effectively been listening for energy travelling through the heart of another planet, and now we’ve heard it.

    “These first measurements of the elastic properties of Mars’ core have helped us investigate its composition. Rather than being just a ball of iron, it also contains a large amount of sulfur, as well as other elements including a small amount of hydrogen.”

    The team of researchers used data from NASA’s InSight lander, a robotic spacecraft designed to probe the interior of Mars, to compare seismic waves travelling through the planet’s core with those transiting Mars’ shallower regions, and modelled properties of its interior.

    The InSight lander deployed a broadband seismometer on the Martian surface in 2018, allowing for the detection of seismic events, including marsquakes and meteorite impacts.  The multi-disciplinary team of scientists, including seismologists, geodynamicists and mineral physicists, used observations of two seismic events located in the opposite hemisphere from the seismometer to measure the travel times of seismic waves that passed through the core relative to seismic waves that remained in the mantle. 

    Dr Irving said: “So-called ‘farside’ events, meaning those on the opposite side of the planet to InSight, are intrinsically harder to detect because a great deal of energy is lost or diverted away as waves travel through the planet. We needed both luck and skill to find, and then use, these events. We detected no farside events in the first Martian year of operations. If the mission had ended then, this research couldn’t have happened.

    “The sol 976 marsquake was the most distant event found during the mission. The second farside event, S1000a – the first event detected on day 1,000 of operations – was particularly useful because it turned out to be a meteorite impact which we heard all the way through the planet, so we knew where the seismic signals came from. These events came after the Marsquake Service (MQS) had honed their skills on hundreds of days of Martian data; it then took a lot of seismological expertise from across the Insight Team to tease the signals out from the complex seismograms recorded by the lander.”  

    The authors used these measurements to build models describing physical properties of the core, including its size and elastic wave-speed. The results suggested Mars’ core is slightly denser and smaller than previous estimates, with a radius of approximately 1,780–1,810 km. These findings are consistent with the core having a relatively high fraction of light elements alloyed with iron, including abundant sulfur and smaller amounts of oxygen, carbon and hydrogen.

    Co-author Ved Lekic, Associate Professor of Geology at the University of Maryland College Park, in the US, said: “Detecting and understanding waves that travel through the very core of another planet is incredibly challenging, reflecting decades of efforts by hundreds of scientists and engineers from multiple countries. We not only had to utilise sophisticated seismic analysis techniques, but also deploy knowledge of how high pressures and temperatures affect properties of metal alloys, leveraging the expertise of the InSight Team.”

    Dr Irving added: “The new results are important for understanding how Mars’ formation and evolution differ from those of Earth. New theories about the formation conditions and building blocks of the red planet will need to be able to match the core’s physical properties as revealed by this new study.”

    Dr Jessica Irving and co-author Dr Anna Horleston, a seismologist from the University of Bristol, were supported with funding from the UK Space Agency.

    Paper

    ‘First observations of core-transiting seismic phases on Mars’ by Jessica Irving et al in PNAS 

    Image

    Sol 980: Instrument Context Camera (ICC) – NASA’s InSight Mars Lander

     

    University of Bristol

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  • New biography of famous palaeontologist Mary Anning unearthed from University of Bristol archives

    New biography of famous palaeontologist Mary Anning unearthed from University of Bristol archives

    Newswise — A short biography of pioneering scientist Mary Anning, written in the final ten years of her life, has been made public for the very first time.

    Penned by George Roberts (1804–1860), who ran a private school opposite Anning’s fossil shop in Lyme Regis, and preserved in the Special Collections of the University of Bristol Library, the work has been published by Dr Michael Taylor of National Museums Scotland and University of Leicester and Professor Michael Benton of Bristol’s School of Earth Sciences.

    Mary Anning (1799–1847) of Lyme Regis has been the subject of recent books and films, such as Tracy Chevalier’s Remarkable Creatures, and Ammonite, in which she was portrayed by Kate Winslet, because of her importance in the early days of palaeontology. She collected some of the first marine reptiles – ichthyosaurs and plesiosaurs – from the Jurassic period of the Dorset coast. Noted professors relied on her work to provide insights into the life of the past.

    Mary Anning has become an icon of the often-forgotten contributions of women to science, and the campaign to get children, especially girls, interested in geology. But, in her day, she was a curiosity, another poor person in the Regency seaside resort of Lyme Regis.

    “When the Library sent me a copy of the four-page manuscript, I found that it was based partly on a passage in Roberts’s history of Lyme Regis,” said Dr Taylor. “Roberts wrote books like ‘The Beauties of Lyme Regis’ for tourists, and he collected interesting pieces of information. We were able to confirm Anning expert Hugh Torrens’s suggestion that it was by Roberts, by identifying Roberts’s handwriting, and comparing the corrections and even a mistake with a particular date which Roberts had handwritten into his own copy of his history. So, it wasn’t just someone else copying from his book. It looks as if it was written as a dictionary entry or a section for a future book.”

    “This memoir is valuable,” said Prof Benton. “One or two visitors to Lyme Regis mentioned Mary Anning and her little fossil shop, and she was obviously widely known to natural scientists in London, Bristol, Oxford, and Cambridge. But normally they would not enquire into her life in any detail. Admittedly though, when she died at the relatively young age of 48, she had obituaries in various papers and scientific journals.”

    Dr Taylor said: “These short obituaries were often copied from one written by George Roberts. George Roberts lived in Lyme Regis and met her many times. He describes how she was struck by lightning as a baby, and then how at the age of about ten she began collecting fossils, and how she sold her first find, an ammonite to a passing lady in the street for half a crown.”

    There are further details of her discoveries of fossil reptiles, including the first ichthyosaur fossil studied by scientists. It was described by Sir Everard Home in 1818. Mary Anning was granted a government annuity of £25 per year in 1836 thanks to an intervention by Fellows of the Geological Society of London, and she died of breast cancer in 1847.

    “We dated the manuscript as written some time in 1837–47,” added Dr Taylor, “because there is an ‘1837’ watermark in the paper, and Anning was described as a ‘living worthy’. Later,  Roberts took the manuscript, deleted mention of Anning as alive, and added information on her death to make it into an obituary, presumably just after she died. But it seems never to have been published at its full length.”

    Prof Benton concluded: “We are very pleased that we are able to publish the document in full.

    “In the paper, we show detailed photographs of all four pages of the document, as well as our reading of the various versions and modifications. George Roberts was the locally-based author who reported the news from Lyme Regis to various newspapers and wrote his own books, so it makes complete sense that he would have written about Mary Anning as a well-known celebrity of the town.”

    Paper:

    ‘The life of Mary Anning, fossil collector of Lyme Regis: a contemporary biographical memoir by George Roberts’ by Michael A. Taylor and Michael J. Benton in Journal of the Geological Society.

     

    Notes to Editors

    The memoir (DM Ref SCUBL DM1186/5/1) is in the collection of books and manuscripts in the history of geology made by Joan M. Eyles (1907–1986) and Victor A. Eyles (1895–1978) and donated by Joan Eyles to the University of Bristol Library.

    University of Bristol

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  • Scientists discover what was on the menu of the first dinosaurs

    Scientists discover what was on the menu of the first dinosaurs

    Newswise — The earliest dinosaurs included carnivorous, omnivorous and herbivorous species, according to a team of University of Bristol palaeobiologists.

    By looking at the tooth shapes of the earliest dinosaurs and simulating their tooth function with computational modelling, experts were able to compare them to living reptiles and their diets. Their findings, published today in Science Advances, show that many groups of plant-eating dinosaurs were ancestrally omnivorous and that the ancestors of our famous long-necked herbivores, such as Diplodocus, ate meat. This ability to diversify their diets early in their evolution likely explains their evolutionary and ecological success.

    The earliest dinosaurs are enigmatic: they were much smaller than their later relatives and for most of the Triassic they were in the shadow of the crocodile-like reptiles. It is unknown how diverse they were in terms of diets and ecology, but scientists know something must have happened in the Triassic that allowed dinosaurs to endure the Triassic–Jurassic mass extinction and adapt in its aftermath, becoming the dominant group for the rest of the Mesozoic.

    Lead author Dr. Antonio Ballell from the University of Bristol said “Soon after their origin, dinosaurs start to show an interesting diversity of skull and tooth shapes. For decades, this has made palaeontologists suspect that different species were already experimenting with different kinds of diets. They have compared them to modern lizard species and tried to infer what they ate based on the similarities in their teeth.

    “We investigated this by applying a set of computational methods to quantify the shape and function of the teeth of early dinosaurs and compare them to living reptiles that have different diets. This included mathematically modelling their tooth shapes and simulating their mechanical responses to biting forces with engineering software.”

    Professor Mike Benton, co-author of the study, said: “With this battery of methods, we were able to numerically quantify how similar early dinosaurs were to modern animals, providing solid evidence for our inferences of diets. Theropod dinosaurs have pointy, curved and blade-like teeth with tiny serrations, which behaved like those of modern monitor lizards. In contrast, the denticulated teeth of ornithischians and sauropodomorphs are more similar to modern omnivores and herbivores, like iguanas.”

    The study is also innovative in using machine learning models to classify the earliest dinosaurs in different diet categories based on their tooth shape and mechanics. For instance, Thecodontosaurus, the Bristol dinosaur, had teeth well adapted for a diet of plants.

    Professor Emily Rayfield, senior co-author, said: “Our analyses reveal that ornithischians – the group that includes many plant-eating species like the horned dinosaurs, the armoured ankylosaurs and the duck-billed dinosaurs – started off as omnivores. And another interesting finding is that the earliest sauropodomorphs, ancestors of the veggie long-necked sauropods like Diplodocus, were carnivores. This shows that herbivory was not ancestral for any of these two lineages, countering traditional hypotheses, and that the diets of early dinosaurs were quite diverse.”

    Dr. Ballell concluded: “It seems that one of the things that made the first dinosaurs special is that they evolved different diets throughout the Triassic, and we think this might have been key for their evolutionary and ecological success.”

    Dinosaurs dominated the land during the Mesozoic era until their extinction 66 million years ago. They included giant veggie groups like the long-necked sauropods and meat-eating species like Tyrannosaurus rex and its relatives. However, their origins were much humbler and date back to the Triassic period, with the first definitive dinosaurs appearing approximately 235 million years ago.

     

    Paper:

    ‘Dental form and function in the early feeding diversification of dinosaurs’ by Antonio Ballell, Michael J. Benton and Emily J. Rayfield in Science Advances.

    DOI: 10.1126/sciadv.abq5201

    University of Bristol

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  • Fossil discovery in storeroom cupboard shifts origin of modern lizard back 35 million years

    Fossil discovery in storeroom cupboard shifts origin of modern lizard back 35 million years

    Newswise — A specimen retrieved from a cupboard of the Natural History Museum in London has shown that modern lizards originated in the Late Triassic and not the Middle Jurassic as previously thought.

    This fossilised relative of living lizards such as monitor lizards, gila monsters and slow worms was identified in a stored museum collection from the 1950s, including specimens from a quarry near Tortworth in Gloucestershire, South West England. The technology didn’t exist then to expose its contemporary features.

    As a modern-type lizard, the new fossil impacts all estimates of the origin of lizards and snakes, together called the Squamata, and affects assumptions about their rates of evolution, and even the key trigger for the origin of the group.

    The team, led by Dr David Whiteside of Bristol’s School of Earth Sciences, have named their incredible discovery Cryptovaranoides microlanius meaning ‘small butcher’ in tribute to its jaws that were filled with sharp-edged slicing teeth.

    Dr Whiteside explained: “I first spotted the specimen in a cupboard full of Clevosaurus fossils in the storerooms of the Natural History Museum in London where I am a Scientific Associate. This was a common enough fossil reptile, a close relative of the New Zealand Tuatara that is the only survivor of the group, the Rhynchocephalia, that split from the squamates over 240 million years ago.

    “Our specimen was simply labelled ‘Clevosaurus and one other reptile.’ As we continued to investigate the specimen, we became more and more convinced that it was actually more closely related to modern day lizards than the Tuatara group.

    “We made X-ray scans of the fossils at the University, and this enabled us to reconstruct the fossil in three dimensions, and to see all the tiny bones that were hidden inside the rock.”

    Cryptovaranoides is clearly a squamate as it differs from the Rhynchocephalia in the braincase, in the neck vertebrae, in the shoulder region, in the presence of a median upper tooth in the front of the mouth, the way the teeth are set on a shelf in the jaws (rather than fused to the crest of the jaws) and in the skull architecture such as the lack of a lower temporal bar. There is only one major primitive feature not found in modern squamates, an opening on one side of the end of the upper arm bone, the humerus, where an artery and nerve pass through. Cryptovaranoides does have some other, apparently primitive characters such as a few rows of teeth on the bones of the roof of the mouth, but experts have observed the same in the living European Glass lizard and many snakes such as Boas and Pythons have multiple rows of large teeth in the same area. Despite this, it is advanced like most living lizards in its braincase and the bone connections in the skull suggest that it was flexible.

    “In terms of significance, our fossil shifts the origin and diversification of squamates back from the Middle Jurassic to the Late Triassic,” says co-author Professor Mike Benton. “This was a time of major restructuring of ecosystems on land, with origins of new plant groups, especially modern-type conifers, as well as new kinds of insects, and some of the first of modern groups such as turtles, crocodilians, dinosaurs, and mammals.

    “Adding the oldest modern squamates then completes the picture. It seems these new plants and animals came on the scene as part of a major rebuilding of life on Earth after the end-Permian mass extinction 252 million years ago, and especially the Carnian Pluvial Episode, 232 million years ago when climates fluctuated between wet and dry and caused great perturbation to life.”

    PhD research student Sofia Chambi-Trowell commented: “The name of the new animal, Cryptovaranoides microlanius, reflects the hidden nature of the beast in a drawer but also in its likely lifestyle, living in cracks in the limestone on small islands that existed around Bristol at the time. The species name, meaning ‘small butcher,’ refers to its jaws that were filled with sharp-edged slicing teeth and it would have preyed on arthropods and small vertebrates.”

    Dr Whiteside concluded: “This is a very special fossil and likely to become one of the most important found in the last few decades. It is fortunate to be held in a National Collection, in this case the Natural History Museum, London. We would like to thank the late Pamela L. Robinson who recovered the fossils from the quarry and did a lot of preparation work on the type specimen and associated bones. It was such a pity she did not have access to CT scanning technology to help her observe all the detail of the specimen.”

     

    The paper:

    ‘A Triassic crown clade squamate’ by Whiteside, D. I., Chambi-Trowell, S. A. V., and Benton, M J. Science Advances 8, eabq8274.

     

    University of Bristol

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  • Pocket feature shared by deadly coronaviruses could lead to pan-coronavirus antiviral treatment

    Pocket feature shared by deadly coronaviruses could lead to pan-coronavirus antiviral treatment

    Newswise — Scientists have discovered why some coronaviruses are more likely to cause severe disease, which has remained a mystery, until now. Researchers of the University of Bristol-led study, published in Science Advances today [23 November], say their findings could lead to the development of a pan-coronavirus treatment to defeat all coronaviruses—from the 2002 SARS-CoV outbreak to Omicron, the current variant of SARS-CoV-2, as well as dangerous variants that may emerge in future.

    In this new study, an international team, led by Bristol’s Professor Christiane Schaffitzel, scrutinised the spike glycoproteins decorating all coronaviruses. They reveal that a tailor-made pocket feature in the SARS-CoV-2 spike protein, first discovered in 2020, is present in all deadly coronaviruses, including MERS and Omicron. In striking contrast, the pocket feature is not present in coronaviruses which cause mild infection with cold-like symptoms.

    The team say their findings suggest that the pocket, which binds a small molecule, linoleic acid—an essential fatty acid indispensable for many cellular functions including inflammation and maintaining cell membranes in the lungs so that we can breathe properly—could now be exploited to treat all deadly coronaviruses, at the same time rendering them vulnerable to a linoleic acid-based treatment targeting this pocket.   

    COVID-19, caused by SARS-CoV-2, is the third deadliest coronavirus outbreak following SARS-CoV in 2002 and MERS-CoV in 2012. The much more infectious SARS-CoV-2 continues to infect people and damage communities and economies worldwide, with new variants of concern emerging successively, and Omicron evading vaccination and immune response.

    Professor Schaffitzel from Bristol’s School of Biochemistry, explained: “In our earlier work we identified the presence of a small molecule, linoleic acid, buried in a tailor-made pocket within the SARS-Cov-2 glycoprotein, known as the ‘Spike protein’, which binds to the human cell surface, allowing the virus to penetrate the cells and start replicating, causing widespread damage.

    “We showed that binding linoleic acid in the pocket could stop virus infectivity, suggesting an anti-viral treatment. This was in the original Wuhan strain that started the pandemic. Since then, a whole range of dangerous SARS-CoV-2 variants have emerged, including Omicron, the currently dominating variant of concern. We scrutinised every new variant of concern and asked whether the pocket function is still present.”

    Omicron has undergone many mutations, enabling it to escape immune protection offered by vaccination or antibody treatments that lag behind this rapidly evolving virus.  Intriguingly, while everything else may have changed, the researchers found that the pocket remained virtually unaltered, also in Omicron.

    Christine Toelzer, Research Associate in the School of Biochemistry and lead author of the study, added: “When we realised that the pocket we had discovered remained unchanged, we looked back and asked whether SARS-CoV and MERS-CoV, two other deadly coronaviruses causing previous outbreaks years ago, also contained this linoleic acid binding pocket feature.”  

    The team applied high-resolution electron cryo-microscopy, cutting-edge computational approaches and cloud computing. Their results showed that SARS-CoV and MERS-CoV also had the pocket, and could bind the ligand, linoleic acid, by a virtually identical mechanism.  

    Professor Schaffitzel concluded: “In our current study, we provide evidence that the pocket remained the same in all deadly coronaviruses, from the first SARS-CoV outbreak 20 years ago to Omicron today. We have shown previously that linoleic acid binding to this pocket induces a locked spike, abrogating viral infectivity. We also show now that linoleic acid supplementation suppresses virus replication inside cells. We anticipate that future variants will also contain the pocket, which we can exploit to defeat the virus.”

    Halo Therapeutics, a recent University of Bristol spin-out Professor Schaffitzel co-founded, is using these findings to develop pocket-binding pan-coronavirus antivirals.

    The team included experts from the Bristol UNCOVER Group, Max Planck Bristol Centre for Minimal Biology, Bristol University spin-out Halo Therapeutics Ltd, and collaborators in Sweden and France. The studies have been supported by funds from Max Planck Gesellschaft, Wellcome Trust and European Research Council, with additional support from Oracle for Research for high-performance cloud computing resources.

    Paper

    “The free fatty acid-binding pocket is a conserved hallmark in pathogenic b-coronavirus spike proteins from SARS-CoV to Omicron” by C Toelzer et al. in Science Advances

    University of Bristol

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  • Fertilisers Limit Pollination by Changing How Bumblebees Sense Flowers

    Fertilisers Limit Pollination by Changing How Bumblebees Sense Flowers

    Newswise — Pollinators are less likely to land on flowers sprayed with fertilisers or pesticides as they can detect electric field changes around the flower, researchers at the University of Bristol have found.

    The study, published in PNAS Nexus today, shows that chemical sprays alter the electric field around flowers for up to 25 minutes after exposure. This impact lasts substantially longer than natural fluctuations, such as those caused by wind, and causes a reduction in bee feeding effort in nature.

    Dr Ellard Hunting of Bristol’s School of Biological Sciences and his team noted that fertilisers did not affect vision and smell, and set out to mimic the electrical changes caused by fertilisers and pesticides in the field by electrically manipulating flowers. This showed that bumblebees were able to detect and discriminate against the small and dynamic electric field alterations that are caused by the chemicals.

    Dr. Ellard Hunting said: “We know that chemicals are toxic, but we know little about how they affect the immediate interaction between plants and pollinators.

    “Flowers have a range of cues that attract bees to promote feeding and pollination. For instance, bees use cues like flower odour and colour, but they also use electric fields to identify plants.

    “A big issue is thus – agrochemical application can distort floral cues and modify behaviour in pollinators like bees.”

    Furthermore, various other airborne particles such as nanoparticles, exhaust gasses, nano-plastics, and viral particles may have similar impacts, affecting a wide array of organisms that use the electric fields that are virtually everywhere in the environment.

    Co-author, Bristol’s Sam England, explained: “What makes this study important is that it’s the first known example of anthropogenic ‘noise’  interfering with a terrestrial animal’s electrical sense.

    ”It’s much like motorboat noise that hinders the ability of fish to detect their predators, or artificial light at night that confuses moths; the fertilisers are a source of noise to bees trying to detect floral electrical cues.

    “This widens our understanding of the multifaceted ways in which human activity is negatively impacting the natural world, which can seem quite depressing, but it will hopefully allow is to introduce or invent solutions to prevent the adverse effects that these chemicals may be having on bees.”

    Dr Ellard Hunting added: “The fact that fertilisers affect pollinator behavior by interfering with the way an organism perceives its physical environment offers a new perspective on how human-made chemicals disturb the natural environment.”

    The project was funded by the European Research Council and the Swiss National Science Foundation.

    Paper:

     

    ‘Synthetic fertilizers alter floral biophysical cues and bumblebee foraging behaviour’ by E Hunting, S England et al in PNAS Nexus.

    University of Bristol

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  • Patient-Specific Cancer Tumours Replicated in 3D Bioprinting Advance

    Patient-Specific Cancer Tumours Replicated in 3D Bioprinting Advance

    Externally peer reviewed: Yes

    Evidence type: Experimental study

    Subjects: Cells

     

    Newswise — Bowel cancer patients could in future benefit from a new 3D bioprinting technology which would use their own cells to replicate the complex cellular environment of solid tumours in 3D models. The University of Bristol-led advance, published in Biofabrication, would allow clinicians to treat the models, known as spheroids, with chemotherapy drugs and radiation to help them understand an individual patient’s resistance to therapies.

    Bowel cancer is the third-most prevalent cancer worldwide, a major cause of cancer-related deaths and is becoming more prevalent globally each year. While current therapies aim to shrink tumours through a combination of surgery, chemotherapy and/or radiotherapy, the heterogenous nature of bowel tumours mean that chemotherapy drugs have variable effects between patients. 

    In this new study, researchers developed a new 3D bioprinting platform with high content light microscopy imaging and processing. Using a mixture of bioinks and colorectal cancer cells, the team show they were able to replicate tumours in 3D spheroids.

    To investigate how the tumours might respond to drugs, dose-response profiles were generated from the spheroids which had been treated separately with chemotherapy drugs oxaliplatin (OX), fluorouracil (5FU), and radiotherapy. The spheroids were then imaged over time. Results from their experiment showed oxaliplatin was significantly less effective against tumour spheroids than in current 2D monolayer culture structures, when compared to fluorouracil.

    Professor Adam Perriman, Professor of Bioengineering from Bristol’s School of Cellular and Molecular Medicine, and founder of the cell therapy company CytoSeek, and the study’s lead author, explains the technology’s significance: “Clinically predictive models which allow clinicians to identify how well tumours respond to drugs before they are administered in patients, are still an unmet need. Two dimensional (2D) cell monolayer culture remains the standard for modelling in vitro drug effectiveness and safety. However, its poor in vivo predictive capability inhibits its use as a tool for drug discovery, drug repositioning and personalised medicine.

    “We have developed a high-throughput bioprinted bowel cancer spheroid platform with high levels of automation, information content, and low cell number requirement that mimics the 3D characteristics of tumours, and show that some tumours are more resistant to chemotherapy.

    “We anticipate that this new platform technology could have significant impact in human disease modelling for evaluation of oncology drug-response in 3D. This is a big step towards personalised medicine and helping to understand why certain patients respond to chemotherapy.”

    The study was supported by grants from the UKRI Future Leaders Fellowship, the EPSRC and the BBSRC Centre for Doctoral Training in Synthetic Biology.

    Paper

    A rapid high throughput bioprinted colorectal cancer spheroid platform for in vitro drug- and radiation-response by Adam W. Perriman et al. in Biofabrication.

    Ends

    Notes to editors

    Image available to download

    https://fluff.bris.ac.uk/fluff/u2/ficmc/co3MHXxxn_reIM5Lx2lUhA9MO/

    Caption: Electron micrograph of a grown, hydrogel-embedded tumour spheroid.

    Credit: University of Bristol

    Issued by the University of Bristol, UK.

    University of Bristol

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  • Pioneering research directly dates the earliest milk use in prehistoric Europe

    Pioneering research directly dates the earliest milk use in prehistoric Europe

    Newswise — A new study has shown milk was used by the first farmers from Central Europe in the early Neolithic era around 7,400 years ago, advancing humans’ ability to gain sustenance from milk and establishing the early foundations of the dairy industry.

    The international research, led by the University of Bristol and published today in Proceedings of the National Academy of Sciences (PNAS), deployed a pioneering technique to date dairy fat traces preserved in the walls of pottery vessels from the 54th Century BC. This method targets fatty acids from animal fat residues, making it uniquely suited to pinpointing the introduction of new foodstuffs in prehistoric times.

    Lead author Dr Emmanuelle Casanova, who conducted the research while completing her PhD in archaeological chemistry at the University of Bristol, said: “It is amazing to be able to accurately date the very beginning of milk exploitation by humans in prehistoric times. The development of agropastoralism transformed prehistoric human diet by introducing new food commodities, such as milk and milk products, which continues to the present day.”

    These settlers of South East, East, and West of Europe were the earliest Neolithic farming groups in Central Europe, known as the Linearbandkeramik (LBK) culture. The findings of this research showed some of the very first settlers in the region were using milk at scale.

    This work was part of the European Research Council (ERC) NeoMilk project led by Professor Richard Evershed FRS of the School of Chemistry at the University of Bristol. His team analysed more than 4,300 pottery vessels from 70 LBK settlements for their food residues. The results revealed considerable variation in milk use across the region, with only 65 percent sites presenting evidence of dairy fats in ceramics vessels, suggesting milk use, while common, was not universally adopted by these early farmers.

    Focussing on the sites and ceramics with dairy residues, the researchers produced around 30 new radiocarbon dates to chart the advent of dairy exploitation by LBK farmers. These new dates correspond to the earliest LBK settlements during the middle of the 6th Millenium BC.

    Co-lead author Professor Evershed said: “This research is hugely significant as it provides new insights into the timing of major changes in human food procurement practices, as they evolved across Europe. It provides clear evidence that dairy foods were in widespread circulation in the Early Neolithic, despite variations in the scale of activity.”

    The study was conducted in collaboration with chemists from the University of Bristol and archaeologists from the Universities of Gdańsk, Paris 1, Strasbourg, Leiden, and Adam Mickiewicz, the Dobó István Castle Museum, Historic England, and the LVR-State Service for Archaeological Heritage, which directed excavations of the studied sites.

    Notes to editors

    Dr Emmanuelle Casanova, currently a post-doctoral research fellow at the National Museum of Natural History in Paris, and Professor Richard Evershed are available for interview and advance copies of the study are available on request.

    University of Bristol

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