Researchers from the University of Cambridge, the University of East Anglia (UEA) and the Peruvian Ministry of Environment assessed the effectiveness of different approaches to conservation in the Peruvian Amazon between 2006 and 2011. They found that while all were effective at protecting the rainforest compared with non-protected areas of land, the areas protected by local and indigenous communities were on average more effective than those protected by the government.

However, the effectiveness of the conservation strategies also depended on what non-protected areas they were compared to, and the land use restrictions in place in the non-protected land. Future assessments of the impacts of different conservation strategies should therefore pay closer attention to land use restrictions in place in non-protected lands. The results are reported in the journal Scientific Reports.

Although the Amazon rainforest and its unique biodiversity are rapidly disappearing, little is still known about which protection mechanisms make a difference and how different conservation strategies compare.

The study looked at areas protected by the national government, indigenous communities or civil society and the private sector are, compared to non-protected areas and land destined for timber and mineral extraction. The researchers assessed each approach for how well it was able to curtail deforestation, defined as total forest cover loss, and forest degradation, defined as other human-induced disturbances, such as selective logging, logging tracks and fire.

The researchers combined remote sensing data with environmental and socio-economic datasets to assess each approach, and controlled for other factors that are expected to affect deforestation and forest degradation.

“Our results that these diverse types of protected areas were effective at reducing deforestation and forest degradation compared to non-protected areas are very encouraging,” said lead author Dr Judith Schleicher, from Cambridge’s Department of Geography. The larger reduction in deforestation and forest degradation in areas led by indigenous communities and grassroots groups suggests that local ownership and support for protecting the Peruvian Amazon can be a particularly effective approach.

“Policy makers must focus on a more diverse set of mechanisms for protecting the rapidly disappearing tropical forests,” said Schleicher. “Our analysis shows that local stewardship of the forest can be very effective at curtailing forest degradation and conversion in the Peruvian Amazon. Local conservation initiatives deserve more political, financial and legal support than they currently receive.”

“Our analysis shows that there is no single way of protecting tropical forests, and multiple approaches are required to stem the relentless tide of forest conversion and degradation,” said co-author Professor Carlos Peres from UEA’s School of Environmental Sciences.

The research was supported by the Economic and Social Research Council, the Cambridge Political Economy Society, Cambridge Philosophical Society, St John’s College, and the Department of Geography.

Reference:
Judith Schleicher et al. ‘Conservation performance of different conservation governance regimes in the Peruvian Amazon.’ Scientific Reports (2017). DOI: 10.1038/s41598-017-10736-w

In a study published in 2009, results from a clinical trial carried out in Thailand found that an experimental vaccine against HIV lowered the rate of human infection by 31%. This gave cautious optimism that a vaccine against the virus might be a feasible prospect. A vaccine has obvious advantages over treatment with anti-retroviral drugs in that prevention could lead to eradication.

However, one of the major problems that prevented the vaccine from generating long-lasting protection was that the key immune response it needed to generate was very short-lived. The reason has now become clear and researchers have found a potential solution.

When a virus enters the body, its aim is to get into our cells and replicate itself again and again, spreading throughout the body. HIV is especially notorious because a protein on its outer coat specifically targets CD4 T-helper cells, the master regulators of the immune system.  These cells produce important signals for other types of immune cell: B-cells, which make antibodies; and T-killer cells, which kill virus-infected cells.

By specifically targeting the CD4 T-helper cells, HIV cripples the command and control centre of the immune system and prevents immune defences from working effectively. HIV does not even need to enter and kill the CD4 T-cells – it can cause a functional paralysis of these cells simply by binding its gp140 with the CD4 receptor, an important molecule on the surface of T-helper cells.

HIV’s envelope proteins are a key component of vaccines to protect against HIV infection. The body’s immune system targets this protein and generates antibodies directed at HIV’s outer coat to prevent the virus from entering the cells. If the effects of the vaccine last long enough, then with the assistance of robust helper T-cells, the human body should be able to develop antibodies that neutralise a large variety of HIV strains and protect people from infection.

Previous studies showed that vaccinating using a form of the outer coat protein called gp140 leads to the triggering of B-cells which produce antibodies to the virus, but only for a brief period and insufficient to generate sufficient antibodies that are protective from HIV infection over a long period.

Working with scientists in the UK, France, the USA, and the Netherlands, Professor Jonathan Heeney from the Laboratory of Viral Zoonotics at the University of Cambridge recognised that the binding of gp140 to the CD4 receptor on T-helper cells was probably causing this block, and that by preventing gp140 attaching to the CD4 receptor, the short-term block in antibody producing B-cells could be overcome.

In two back-to-back studies published in the print edition of Journal of Virology, the research team has demonstrated for the first time that this approach works, providing the desired responses that were capable of lasting over a year.  

“For a vaccine to work, its effects need to be long lasting,” says Professor Heeney. “It isn’t practical to require people to come back every 6-12 months to be vaccinated. We wanted to develop a vaccine to overcome this block and generate these long-lived antibody producing cells. We have now found a way to do this.”

The study showed that the addition of a tiny specific protein patch to the gp140 protein dramatically improved B-cell responses by blocking binding to the CD4 receptor and hence preventing the paralysis of T-helper cells early in the key stages of the immune response – like preventing a key from getting stuck in a lock. This small patch was one of several strategies to improve gp140 for an HIV vaccine by a team led by Susan Barnett (now at the Bill and Melinda Gates Foundation).

This modified vaccine approach now better stimulates long-lasting B-cell responses, boosting the ability of B-cells to recognise different contours of the virus coat and to make better antibodies against it. This new finding will allow HIV vaccines to be developed that give the immune system enough time to develop the essential B-cell responses to make protective antibodies.

“B-cells need time to make highly effective neutralising antibodies, but in previous studies B-cell responses were so short lived they disappeared before they have the time to make all the changes necessary to create the ‘silver bullets’ to stop HIV,” adds Professor Heeney.

“What we have found is a way to greatly improve B-cell responses to an HIV vaccine. We hope our discovery will unlock the paralysis in the field of HIV vaccine research and enable us to move forward.”

The team now hopes to secure funding to test their vaccine candidate in humans in the near future.

The studies were funded by the National Institutes of Health, USA, and the Isaac Newton Trust Cambridge.

Reference

Bogers, WMJM, et al. Increased, Durable B-Cell and ADCC Responses Associated with T-Helper Cell Responses to HIV-1 Envelope in Macaques Vaccinated with gp140 Occluded at the CD4 Receptor Binding Site. Journal of Virology; DOI: 10.1128/JVI.00811-17.

Shen, X et al. Cross-Linking of a CD4-Mimetic Miniprotein with HIV-1 Env gp140 Alters Kinetics and Specificities of Antibody Responses against HIV-1 Env in Macaques. Journal of Virology; DOI: 10.1128/JVI.00401-17. 

The planet, WASP-19b, has about the same mass as Jupiter, but is so close to its parent star that it completes an orbit in just 19 hours and its atmosphere is estimated to have a temperature of about 2000 degrees Celsius. Such planets are known as ‘hot Jupiters’.

As WASP-19b passes in front of its parent star, some of the starlight passes through the planet’s atmosphere and leaves subtle molecular fingerprints in the light that eventually reaches Earth. “Detecting these molecules is no simple feat,” said lead author Elyar Sedaghati, an ESO fellow and recent graduate of TU Berlin. “We used an algorithm that explores many millions of spectra spanning a wide range of chemical compositions, temperatures, and cloud or haze properties in order to draw our conclusions.”

Using the FORS2 instrument on the European Southern Observatory’s Very Large Telescope in Chile, the team was able to carefully analyse this light and deduce that the atmosphere contained small amounts of titanium oxide, water and traces of sodium, alongside a strongly scattering global haze.

“Titanium oxide can substantially affect the behaviour of WASP-19b's atmosphere,” said co-author Ryan MacDonald, a PhD student at Cambridge’s Institute of Astronomy. “From altering its temperature structure, to driving strong winds, we are now one step closer to uncovering the nature of this extreme world.”

Titanium oxide (TiO) is rarely seen on Earth, but it in the atmospheres of hot planets like WASP-19b, it can absorb the incoming starlight in the same way that ozone absorbs the incoming sunlight in the Earth’s stratosphere. This causes a temperature inversion in the stratosphere whereby temperature increases with altitude. The energy from the absorbed starlight higher up in the atmosphere is released locally and causes the temperature to be higher in the upper atmosphere and lower further down, the opposite of the normal situation.

“TiO has been predicted to exist in hot Jupiters for over a decade but its conclusive detection has proved elusive in the past,” said co-author Dr Nikku Madhusudhan of Cambridge’s Institute of Astronomy, who oversaw the atmospheric analyses. “The clear detection of the molecule is a major observational advancement – it is an exciting time in exoplanetary science.”

The astronomers collected observations of WASP-19b over a period of more than one year. By measuring the relative variations in the planet’s radius at different wavelengths of light that passed through the exoplanet’s atmosphere and comparing the observations to atmospheric models, they could extrapolate different properties, such as the chemical content, of the exoplanet’s atmosphere.

This new information about the presence of titanium oxide and other metal oxides will allow a deeper understanding of the chemical and physical processes in exoplanetary atmospheres. Looking to the future, once astronomers are able to observe atmospheres of possibly habitable planets, the improved models will give them a much better idea of how to interpret those observations.

“This important discovery is the outcome of a refurbishment of the FORS2 instrument that was done exactly for this purpose,” said co-author Henri Boffin from ESO, who led the refurbishment project. “Since then, FORS2 has become the best instrument to perform this kind of study from the ground.”

Reference:
Elyar Sedaghati et al. “Detection of titanium oxide in the atmosphere of a hot Jupiter.” Nature (2017). DOI: 10.1038/nature23651

Adapted from an ESO press release.

A new study has, for the first time, provided statistical information about the likely rate of venereal disease in a community in 18th century urban England. These rare findings are limited to a single city, but if they are representative of other urban centres, they suggest that the rate of sexually-transmitted infection was both surprisingly high, approximately equal among the two sexes and significantly greater than in rural areas.

Very unusually for a pre-census period, the research succeeded in measuring levels of venereal disease in the city of Chester, as well as its immediate surroundings, during the 1770s. It was carried out by Simon Szreter, Professor of History and Public Policy at St John’s College, University of Cambridge, who used two unique and contemporaneous sources to construct a picture of the rate at which people were contracting syphilis, then known as “the pox”.

He found that STI rates in Chester were surprisingly high. The study estimates that in the mid-1770s, approximately 8% of residents of both sexes had been infected with syphilis before the age of 35. The estimated infection rate among under-35s in rural communities within a 10 mile radius of the city, however, was a little under 1%.

Such figures contrast with the much lower infection rates of modern times. A recently published report by Public Health England, for example, shows that there were 5,920 diagnoses of syphilis across England as a whole during 2016. Even this is abnormally high; it represents the highest level since 1949 and has led to warnings about cuts to sexual health services.

The prevalence of sexually-transmitted diseases during the pre-modern era influenced both fertility and mortality rates, and being able to determine the rate of infection potentially allows historians to make better judgements about population change. But sources containing statistical information about STIs before the start of the 20th century are virtually non-existent, and the rate has therefore typically been regarded as incalculable.

Szreter’s study was made possible by the extraordinary coincidence of two unique pieces of evidence – the Chester Infirmary’s admissions register, or “Journal of Patients”, which survives for the years 1773-5, and a census carried out by an eminent local physician, John Haygarth, in 1774.

Although a national census only began in 1801, Haygarth – who in a further coincidence had studied at St John’s College, where Szreter is now a Fellow – was an unusually enlightened practitioner who developed his own census for Chester to calculate the prevalence of different types of disease.

“When I heard about the infirmary records, I thought, bingo!” Szreter said. “We have just enough information from Haygarth to reconstruct the most probable age structure of the City of Chester in 1774 – the middle of the three years for which we also have detailed information about who was entering the infirmary and why.”

“Not many academics have the chance to collaborate in their research environment with an eminent member of their own College who died over 200 years ago. But this brand new research would have been impossible without Haygarth’s highly original older research from the 1770s.”

The Chester Infirmary recorded 177 cases of “venereal distemper” during the 3 years 1773-5. These would have been treated depending on whether the condition was mild, and therefore likely to have been gonorrhoea (“the clap”), or more serious, and therefore syphilis (“the pox”).

The gruelling but almost universally-accepted treatment for syphilis involved the continual, supervised application of mercury, which caused patients to produce pints of saliva, supposedly flushing out the venereal poisons. Side-effects included swollen gums, mouth ulcers, and severe halitosis. Typically, the process took at least 35 days.

Because of this, Szreter was able to identify likely syphilitic cases at the infirmary depending on the length of stay among patients reporting a venereal “distemper”. He then compared the figure with a set of age-specific estimates about the size of the at-risk population based on Haygarth’s census. Finally, he was able to make a comparable estimate for the rural population within a 10-mile radius of Chester itself.

Together, the results show that almost exactly 8% of residents in Chester had been infected with what was probably syphilis before they were 35, and that the urban population was approximately 8.65 times more likely to contract the disease compared with people living in the surrounding 290 square miles of countryside.

“It is the first time that we have had any historical statistical evidence like this for sexual disease rates anywhere in Britain,” Szreter said. “The demographic story of this period is defined by mortality and fertility, and rates of venereal disease could of course affect both. But because we haven’t been able to study the impact of STIs, much of the history of British population change has been written as if there wasn’t any.”

Aside from his pioneering census work, John Haygarth is known to have kept detailed patient records, which could provide further, valuable information about medicine and disease at this time. So far, these documents have never been found.

Szreter hopes that they may one day turn up, although his own search – including in the St John’s College archives – has proven fruitless to date. “It’s possible that they were thrown away some time after Haygarth’s death,” he added. “If they were ever discovered, it would be the medical historian’s equivalent of finding Richard III in a car park.”

The study, Treatment Rates for the Pox in early modern England, is published in the academic journal, Continuity and Change. 

Prior to joining Cambridge’s Institute for Manufacturing in 2002, he worked as a manager and then a director of the St John’s Innovation Centre – one of Europe’s most successful incubators for technology-based start-ups. Since joining the University, he has played a very active role in the development of innovation and technology management activities throughout the University. He also works closely with companies in the Cambridge cluster, the largest and most successful technology cluster in Europe. He has been involved in a broad range of regional and national policy activities to support innovation.

“This professorship presents an extraordinary opportunity to address how we define and develop the innovation skills and capabilities of engineers so they can address economic and social needs: a challenge that has become critical for the UK given the current global economic and political context,” said Dr Minshall.

In addition to his research in technology and innovation management, Dr Minshall is also a committed teacher and supporter of engineering outreach to the public. He teaches undergraduate and postgraduate students at the University, runs outreach programmes with local schools, and mentors students and researchers to develop their public engagement skills. “The development of future engineers is at the heart of my work,” he said.

In his new role, Dr Minshall will continue to build on his strengths in innovation and technology management, both in the University and in the UK more broadly.

“The UK has long been superb at invention – the creation of new ideas – but we need to develop a generation of engineers able to create and capture value from these new ideas, and provide these innovators with the capabilities to respond to future challenges and opportunities throughout their careers,” he said. “This requires us to take a much more joined-up, long term view of technology, management and policy issues.”

“We're working very hard to make sure that we end up with technologies that change the way the world works,” said Professor Andy Neely, Pro-Vice-Chancellor for Enterprise and Business Relations.

The new professorship has been made possible thanks to a generous donation of £2.5million from Dr John C Taylor OBE, one of the most successful British inventors of the last 50 years.

“You’ve got to have people who move the world forward: innovation is essential to trade, industry and the economy,” said Dr Taylor. “I trust that the new professor of innovation will help people actually create and do things that will improve the world. The British are renowned for their creativity but all too often their invention is commercialised by other countries.”

Dr Taylor, who is a Fellow of the Royal Academy of Engineering (FREng) made his name creating small electrical components that are vital to many pieces of technology. Early electric kettles would not turn off when the water was boiling, meaning that they needed constant supervision and were in danger of melting and starting fires if they were not properly attended. Dr Taylor created the solution to this problem: by supplying a small, bimetallic thermostat to domestic kettle makers which would switch off the kettle element when the water started to boil.  This invention did not dictate the vessel design, being suitable for metal and plastic jugs and kettles, providing a universal solution to manufacturers.

Having continued to innovate throughout his life, Dr Taylor now has over 400 patents to his name. In 2008, he created and donated to his former college the popular Corpus Chronophage Clock, positioned outside the Taylor Library at Corpus Christi College, Cambridge, which has now become one of the city’s most popular tourist attractions.

The new professorship, which has been endowed in perpetuity, will combine teaching and research to ensure young engineers combine innovation with practicality when approaching design.

Professor David Cardwell, Head of the Department of Engineering, said: “We are extremely grateful for this generous benefaction from Dr John C Taylor and honoured that this professorship will not only bear the name of such a distinguished inventor and engineer, but will help future generations to follow in his footsteps.”

Inset image: (L-R): Dr John C Taylor, Dr Tim Minshall, Professor Andy Neely. Credit: www.johnctaylor.com

For the first time, archaeologists have uncovered and carefully documented an intact burial in a monumental chamber tomb of the Mycenaean palatial period, around 3,350 years ago. Research into the material uncovered has only just begun but the discovery will expand our knowledge of Mycenaean funerals – from the treatment of the body to the selection of objects placed for burial.

The tomb is approached by an impressive rock-cut passageway, 20 m long, which leads to a deep façade some 5.40 m in height. A doorway gives access to the burial chamber. Its area of 42 sq m makes this the ninth largest known to date out of 4,000 examples excavated in the last 150 years in Greece. The partial collapse of the original chamber roof has helped to preserve the burial layer intact.

“Mycenaean chamber tombs are generally found by archaeologists to have been disturbed or looted. Most contain many burials, making an association between individual people and objects very difficult or impossible,” said Dr Yannis Galanakis of Cambridge’s Faculty of Classics, co-director of the five-year Prosilio project and an expert in Aegean archaeology.

“Finding an intact burial, let alone in a monumental tomb of the palatial period, 1370-1200 BC, makes our discovery all the more special for the knowledge we can now acquire about the tomb-using group and the practices they performed during and after the funeral.”

Once huge quantities of soil and rubble had been carefully excavated, the archaeologists found in the chamber the remains of a man, aged 40 to 50 years. He was accompanied by a selection of fine objects: jewellery made in a range of materials, combs, pins, a pair of horse bits, arrowheads, a bow, a sealstone, a signet ring, and a group of tinned clay vessels of various shapes.

“The size and quality of construction of the tomb correlates well with the discovered objects, all of which speak of a man from the upper echelons of the local society,” said Galanakis.

“Initial examination of the finds suggests a conscious selection by the tomb-using group responsible for the burial’s preparation of the objects interred with the body. The impression we get is that the tomb was built during the man’s life. It is indeed astonishing, and a very rare instance, to be able to excavate the remains of the man for whom the tomb must have been constructed.”

Galanakis was struck by the placement of different shapes and types of jewellery with a male burial, which challenges the commonly held assumption that jewellery in Mycenaean Greece should be chiefly associated with female burials. “It also chimes with the discovery of considerable quantities of jewellery by the University of Cincinnati in 2015 in the burial of the ‘griffin warrior’ at Pylos, which is older by a century than that of the man at Prosilio.”

Striking too is the absence of painted pottery, with the exception of two painted stirrup jars, often taken to contain aromatic oils and which may be associated with the final use and closure of the tomb around 1300 BC. Painted pottery is very common in Mycenaean tombs. Its absence from the initial burial is further confirmation of the conscious choices made in the selection of objects placed alongside this man’s burial at Prosilio.

The Prosilio team believes that this monumental structure, known as tomb 2, is associated with ancient Orchomenos, a major centre which controlled northern Boeotia, a region of Greece. Orchomenos, which is only 3.5 km away, oversaw in the 14th and 13th centuries BC the partial drainage of Lake Kopaïs – once the largest lake in Greece – a project that yielded a sizeable area of land for agriculture.

At its peak (1350-1250 BC), Orchomenos’s power is reflected in its most famous monument, the tholos tomb ‘of Minyas’, first excavated by Heinrich Schliemann in the 19th century and comparable only in size and refinement to the tholos tomb ‘of Atreus’ at Mycenae.

“Despite the tholos ‘of Minyas’ and some earlier important discoveries by Greek and German teams in the area, we still know very little about ancient Orchomenos. We hope that the continuation of our project will help us understand better Orchomenos’s position in the region and learn more about its population and their practices,” said Galanakis.

“The discovery this year enables us to ask questions such as why certain objects were selected for burial while others were not – and what kind of rituals were performed as part of funerary and post-funerary practices. The finds will spark new discussions about the role of burials in Mycenaean life during the palatial period.”

The five-year Prosilio project is in its first year. In subsequent years, the team aims to excavate more tombs and study and publish the archaeological data collected. The initiative is a collaboration between the Ephorate of Antiquities of Boeotia and the British School at Athens. Its directors are Dr Alexandra Charami (Director of the Ephorate of Antiquities of Boeotia) and Dr Yannis Galanakis, (Senior Lecturer in the Faculty of Classics and Director of the Museum of Classical Archaeology, University of Cambridge).

The Prosilio team also includes Kyriaki Kalliga, archaeologist of the Ephorate of Antiquities of Boeotia, Dr Panagiotis Karkanas, geo-archaeologist and Director of the Wiener Laboratory at the American School of Classical Studies in Athens, Dr Ioanna Moutafi, bio-archaeologist and senior researcher at the Wiener Laboratory, Emily Wright, field supervisor and PhD candidate in Archaeology at the University of Cambridge, and Professor Ann Brysbaert of the University of Leiden and Principal Investigator of the ERC project SETinSTONE. Some 25 students, specialists and workers helped in this year’s fieldwork.

The Prosilio project was conducted with permission from the Hellenic Ministry of Culture & Sports and Ioannis Papadopoulos, the owner of the land. The project was generously funded by, among other sources, the University of Cambridge (Faculty of Classics, the McDonald Institute, the Cambridge Humanities Research Grant scheme, and Sidney Sussex College), the Institute for Aegean Prehistory (INSTAP) and the British School at Athens.

Inset images: entrance to Prosilio tomb 2; horse bits found with the burial (Yannis Galanakis).

Branching patterns occur throughout nature – in trees, ferns and coral, for example – but also at a much finer scale, where they are essential to ensuring that organisms can exchange gases and fluids with the environment efficiently by the maximising the surface area available.

For example, in the small intestine, epithelial tissue is arranged in an array of finger-like protrusions. In other organs, such as kidney, lung, mammary glands, pancreas and prostate, exchange surfaces are packed efficiently around intricate branched epithelial structures.

“On the surface, the question of how these structures grow – structures that may contain as many as 30 or 40 generations of branching – seems incredibly complex,” says Professor Ben Simons, who led the study, published today in the journal Cell. Professor Simons holds positions in the University of Cambridge’s Cavendish Laboratory and Wellcome Trust/Cancer Research UK Gurdon Institute.

This classic problem of ‘branching morphogenesis’ has attracted the attention of scientists and mathematicians for centuries. Indeed, the mathematical underpinnings of morphogenesis – the biological process that causes organisms to develop their shape – was the subject of D’Arcy Wentworth Thompson's classic text, published in 1917 by Cambridge University Press. Thompson had been a student at Cambridge, studying zoology at Trinity College, and briefly worked as a Junior Demonstrator in Physiology.

During development, branching structures are orchestrated by stem-like cells that drive a process of ductal growth and division (or ‘bifurcation’). Each subsequent branch will then either stop growing, or continue to branch again. In a study published in Nature earlier this year, Professor Simons working in collaboration with Dr Jacco van Rheenen at the Hubrecht Institute in Utrecht showed that, in the mammary gland, these processes of division and termination occur randomly, but with almost equal probability.

“While there’s a collective decision-making process going on involving multiple different stem cell types, our discovery that growth occurs almost at the flip of a coin suggested that there may be a very simple rule underpinning it,” says Professor Simons.

Professor Simons and his colleague Dr Edouard Hannezo observed that there was very little crossover of the branches – ducts seemed to expand to fill the space, but not overlap. This led them to conjecture that the ducts were growing and dividing, but as soon as a tip touched another branch, it would stop.

“In this way, you generate a perfectly space-filling network, with precisely the observed statistical organisation, via the simplest local instruction: you branch and you stop when you meet a maturing duct,” says Dr Hannezo, a Sir Henry Wellcome Postdoctoral Fellow based at the Gurdon Institute. “This has enormous implications for the basic biology. It tells you that complex branched epithelial structures develop as a self-organised process, reliant upon a strikingly simple, but generic, rule, without recourse to a rigid, pre-determined sequence of genetically programmed events.”

Although these observations were based on the mammary gland epithelium, by using primary data from Dr Rosemary Sampogna at Columbia University, Professor Anna Philpott in Cambridge and Dr Rakesh Heer at Newcastle University, the researchers were able to show that the same rules governed the embryonic development of the mouse kidney, pancreas and human prostate.

“In the mammary gland, you have a hundred or more fate-restricted stem-like cells participating in this bifurcation-growth-bifurcation process, whereas in the pancreas it’s just a handful; but the basic dynamics are the same,” says Professor Simons. “The model is aesthetically beautiful, because the rules are so simple and yet they are able to predict the complex branching patterns of these structures.”

The researchers say their discovery may offer insights into the development of breast and pancreatic cancer, where the earliest stages of the disease often show an irregular tangled ductal-like organisation.

“A century after the publication of On Growth and Form, it’s exciting to see how the concepts of self-organisation and emergence continue to offer fresh perspectives on the development of biological systems, framing new questions about the regulatory mechanisms operating at the cellular and molecular scale,” Professor Simons adds.

While it may be too early to tell whether similar rules apply to other branched tissues and organisms, there are interesting parallels: branching in trees appears to follow a similar pattern, for example, with side branches growing and bifurcating until they are shaded or until they are screened by another branch, at which point they stop.

The research was funded by the Wellcome Trust with additional core support from Cancer Research UK and the Medical Research Council.

References
Scheele, C et al. Identity and dynamics of mammary stem cells during branching morphogenesis. Nature 542, 313-317 (2017); DOI: 10.1038/nature21046

Hannezo, E et al. A unifying theory of branching morphogenesis. Cell; 14 Sept 2017; DOI: TBC

A new study by researchers at the universities of Cambridge, Oxford, Bristol, and the British Geological Survey provides strong proof that Dickinsonia was an animal, confirming recent findings suggesting that animals evolved millions of years before the so-called Cambrian Explosion of animal life. The study is published in the journal Proceedings of the Royal Society B.

Lead author on the paper is Dr Renee Hoekzema, a PhD candidate at Oxford who carried out this research while completing a previous PhD in Oxford’s Department of Earth Sciences. She said: ‘Dickinsonia belongs to the Ediacaran biota – a collection of mostly soft-bodied organisms that lived in the global oceans between roughly 580 and 540 million years ago. They are mysterious because despite there being around 200 different species, very few of them resemble any living or extinct organism, and therefore what they were, and how they relate to modern organisms, has been a long-standing palaeontological mystery.’

In 1947, Dickinsonia became one of the first described Ediacaran fossils and was initially thought to be an organism similar to a jellyfish. Since then, its strange body plan has been compared to that of a worm, a placozoan, a bilaterian and several non-animals including fungi, lichens and even entirely extinct groups.

Co-author Dr Alex Liu, from Cambridge's Department of Earth Sciences, said: ‘Discriminating between these different hypotheses has been difficult, as there are so few morphological features in Dickinsonia to compare to modern organisms. In this study we took the approach of looking at populations of this organism, including assumed juvenile and adult individuals, to assess how it grew and to try to work out how to classify it from a developmental perspective.’

The research was carried out on the basis of a widely held assumption that growth and development are ‘conserved’ within lineages – in other words, the way a group of organisms grows today would not have changed significantly from the way its ancestors grew millions of years ago.

Dickinsonia is composed of multiple ‘units’ that run down the length of its body. The researchers counted the number of these units in multiple specimens, measured their lengths and plotted these against the relative ‘age’ of the unit, assuming growth from a particular end of the organism. This data produced a plot with a series of curves, each of which tracked how the organism changed in the size and number of units with age, enabling the researchers to produce a computer model to replicate growth in the organism and test previous hypotheses about where and how growth occurred.

Dr Hoekzema said: ‘We were able to confirm that Dickinsonia grows by both adding and inflating discrete units to its body along its central axis. But we also recognised that there is a switch in the rate of unit addition versus inflation at a certain point in its life cycle. All previous studies have assumed that it grew from the end where each “unit” is smallest, and was therefore considered to be youngest. We tested this assumption and interpreted our data with growth assumed from both ends, eventually coming to the conclusion that people have been interpreting Dickinsonia as having grown at the wrong end for the past 70 years.

‘When we combined this growth data with previously obtained information on how Dickinsonia moved, as well as some of its morphological features, we were able to reject all non-animal possibilities for its original biological affinity and show that it was an early animal, belonging to either the Placozoa or the Eumetazoa.

‘This is one of the first times that a member of the Ediacaran biota has been identified as an animal on the basis of positive evidence.’

Dr Liu added: ‘This finding demonstrates that animals were present among the Ediacaran biota and importantly confirms a number of recent findings that suggest animals had evolved several million years before the “Cambrian Explosion” that has been the focus of attention for studies into animal evolution for so long.

‘It also allows Dickinsonia to be considered in debates surrounding the evolution and development of key animal traits such as bilateral symmetry, segmentation and the development of body axes, which will ultimately improve our knowledge of how the earliest animals made the transition from simple forms to the diverse range of body plans we see today.’

Reference:
Renee S. Hoekzema et al. ‘Quantitative study of developmental biology confirms Dickinsonia as a metazoan’. Proceedings of the Royal Society B (2017). DOI: 10.1098/rspb.2017.1348

Adapted from a University of Oxford press release. 

In an article published today in the Journal of Public Mental Health, the team discuss the policy implications of their study published earlier in the year, which found that young people who have contact with mental health services in the community and in clinics are significantly less likely to suffer from clinical depression later in their adolescence than those with equivalent difficulties who do not receive treatment.

Young people’s mental health problems are associated with an increased risk of problems later on in adulthood, including poor mental health, lower income, unemployment, inability to maintain a stable cohabiting relationship, and greater contact with the criminal justice system. However, the team’s previous study suggested that access for adolescents with mental health problems to intervention in schools and clinics reduces mental health problems up to three years later and would therefore yield personal, economic, and societal benefits over an individual’s lifespan.

In the study, Sharon Neufeld and colleagues from the Department of Psychiatry at the University of Cambridge used data obtained between 2005-2010 – prior to funding cuts to Child and Adolescent Mental Health Services in the community and in NHS clinics. Between 2008 and 2013, funding for the services dropped by 5.4 per cent in real terms so that in 2012/2013, only 6 per cent of the NHS’ total mental health budget was spent on these services. The knock-on effect of this was that while in 2005/2006, 38% of 14-year olds with a mental disorder had made contact with mental health provision for young people in the past year, in 2014/2015 only 25% of all children and young people with a mental disorder had made such service contact.

One consequence of this has been that the number of young people attending A&E due to a psychiatric condition had doubled by 2014/2015, compared with 2010/2011.

“It’s important to improve young people’s mental health services in schools and strengthen the care pathway to  specialist Child and Adolescent Mental Health Services, in order to meet the NHS target of returning contact back up to 35% by 2020/2021,” says Mrs Neufeld.

“We need to acknowledge the mental health suffering in our young people that has only been increasingly apparent in recent years, and resolve to improve young people’s access to effective mental health services.”

She and her colleagues argue that as well as protecting funding for specialist Child and Adolescent Mental Health Services, funding for school-based counselling is also important as their study found that this was the second most used service for young people with a mental health disorder.

“The current government has promised to provide funding for mental health first aid training for teachers in secondary schools, which should enable them to better identify those with mental health issues and connect students to the appropriate support services,” says Professor Peter Jones. “But this is against a backdrop of freezing school budgets, the very budgets that typically fund school-based counselling.

“Funding for school-based counselling must be ring-fenced, whether it be funded through the education sector or NHS, to ensure young people have adequate service access prior to specialist mental health services.”

The researchers also argue that GPs could use more training in identifying mental disorder. The Royal College of General Practitioners reports that nine out of ten people with mental health problems are managed in primary care. However, even in the recent past, most GPs do not include a rotation in mental illness as part of their training. Such gaps in training, say the researchers, mean that GPs correctly identify less than a half (47%) of depression cases.

“This is a huge missed opportunity,” adds Professor Ian Goodyer. “GPs will encounter a large number of individuals with mental disorders, but have insufficient background knowledge to appropriately identify such cases.”

Reference
Sharon AS Neufeld, Peter B Jones and Ian M. Goodyer. Child and adolescent mental health services: longitudinal data sheds light on current policy for psychological interventions in the community.  Journal of Public Mental Health; Date; DOI 10.1108/JPMH-03-2017-0013

While we may sometimes make expensive purchases because of the high quality of a product, these items often represent status symbols, a phenomenon termed ‘conspicuous consumption’. Evolutionary psychologists claim that conspicuous consumption may be comparable to ostentatious behaviours or elaborate physical characteristics seen in the animal kingdom. A peacock’s tail may be energetically costly to build, but may serve as an indicator of genetic quality; similarly, conspicuous consumption may represent a costly display of wealth that serves to increase an individual’s social status.

Previous studies have suggested that testosterone plays a key role in human social status seeking, with elevated levels of the hormone being associated with more dominant and aggressive behaviour in men. It has also been suggested that testosterone levels increase in response to an individual winning a competition, and fall in response to losing.

In a study published today in the journal Scientific Reports, Yin Wu, at the time a PhD student at the University of Cambridge, in collaboration with researchers from London Business School, University of Oxford, and University of Vienna, led an investigation into the effects of social status and testosterone levels on conspicuous consumption. Dr Wu tested the effects of winning or losing a competitive version of the game Tetris on the behaviour and testosterone levels of 166 male volunteers – although in fact, while the participants thought they were competing against each other in two-player games, they were randomly assigned as winners or losers.

After playing the Tetris game, the researchers asked the participants how much they would be willing to pay for luxury items such as expensive cars, from 10% of its retail price up to 120%. They found that winners tended to be willing to pay more for these items than losers. This effect was confirmed with some status products made in the laboratory, such that winners were more willing than losers to pay for a Harvard University T-shirt. 

Next, participants were asked to attribute positive and negative words to the items. This task helps assess the implicit value that participants assigned to the objects – in experiments, this is used to measure attitudes that people are unwilling to reveal publicly, and in the field of consumer psychology, these measures can predict brand preferences, usage, and recognition. The current study supported the finding that winners attach greater value than losers to luxury items.

Finally, the researchers measured the participants’ testosterone levels. Contrary to expectations, winning and losing had no observable effect on testosterone levels. This suggests that testosterone does not play a role in conspicuous consumption.

“Winning a competition, which we know is associated with feeling a sense of a higher social status, seems to drive individuals towards conspicuous consumption, making them more willing to pay for luxury items,” says Dr Wu, now based at Shenzhen University in China. “However, we were surprised that testosterone levels did not change with winning or losing, and so testosterone does not seem to be driving the effects on conspicuous consumption.”

The researchers argue that one way in which winning leads to conspicuous consumption is through an enhanced sense of entitlement among winners, the feeling that as winners they are more deserving of preferential treatment than others: the Tetris ‘winners’ may have felt more deserving of the high-status products and also of fair treatment in the ultimatum game. This would be consistent with findings that feelings of superiority over others arising from hard work and success enhance the desire to purchase luxury brands, as individuals see the luxury goods as a reward.

“We are not only interested in examining what people are willing to do to win, but also in understanding the consequences of winning on people’s everyday behaviour,” says Dr Amos Schurr, a behavioural economist at Ben-Gurion University of the Negev, Israel, who was not part of this study.

“Social competition is pervasive in our daily life – whether it is in terms of fighting for the top job, competing for friends and popularity or even growing up in a wealthy, successful family,” says Dr Wu. “Our study demonstrates that winning a competition leads people to prefer high-status products, possibly through an increased feeling of entitlement or deservingness.”

Concerning the null findings on the testosterone levels, the researchers suggested that competition-induced testosterone fluctuations may be hard to detect, and so they are carrying out further work to test the effects of testosterone on conspicuous consumption in their on-going project.

This study was conducted at the University of Cambridge’s Behavioural and Clinical Neuroscience Institute, funded by Medical Research Council and Wellcome Trust.

Reference
Wu, Y et al. The role of social status and testosterone in human conspicuous consumption. Scientific Reports; 18 September 2017; DOI: 10.1038/s41598-017-12260-3

The popular conception of fingerprinting often stems from television detective drama, when a perfect print – with clear arches, loops and whorls – emerges from a powder-dusted window to pin the crime on a tricky culprit, perhaps a well-dressed gentleman safecracker. It is TV fiction, after all.

In the real, developing world, fingerprints are usually not so perfect or so clear. So a start-up connected to Cambridge Judge Business School is using advanced technology to make identification possible for even those with far-from-perfect “last-mile” fingerprints.

“Most biometric systems in use today were designed by and for people in high-income countries,” says Toby Norman, co-founder and CEO of Simprints, which is developing biometrics to help identify and reach the 1.1 billion people around the world without formal identification – a technique that can help medical professionals reach, treat and record these needy people. “In fact, many people in developing countries who have laboured with their hands have burns, scars and worn fingerprints that make them far less easy to read.”

Toby is a former Gates Scholar who holds a PhD in Management Science earned at Cambridge Judge Business School. Cambridge-based Simprints was one of the first start-up teams to be supported by the school’s Entrepreneurship Centre Accelerate Cambridge programme.

“I did part of my PhD research among community health workers in Bangladesh, and was really shocked by the difficulty in identifying patients – many of whom had no formal government ID, had both surnames and family names that overlapped with many other people in their community, and didn’t even know their precise date of birth,” says Toby. “We think that the technology we’re developing can make a big, measurable difference in delivering healthcare.”

Simprints has just been awarded a $2 million “Transition to Scale” innovation grant from Saving Lives at Birth: A Grand Challenge for Development, a programme funded by the Gates Foundation and other donors, that will help better reach these last-mile recipients. The grant – one of just 15 awarded out of 550 applications – will specifically be used to allow Simprints to scale up a maternal healthcare programme in Bangladesh, to track whether 2.56 million expecting mothers across the south Asian country are receiving proper ante and postnatal care.

With a matching $200,000 grant from Cambridge-based chip designer ARM Ltd., Simprints will also expand its capacity to integrate into other global technology systems around the world, allowing Simprints technology to be used in more sectors and contexts. Currently, Simprints technology is in use in Bangladesh, Nigeria, Uganda, Nepal, Zambia, Kenya, and Afghanistan.

In addition, Simprints received a separate Seed Fund grant for $250,000 from Saving Lives at Birth to develop the world’s first neonate scanner – based on research at the University of Cambridge that found it is possible to use biometric fingerprinting on infants as young as six months old. Previously, it has been widely believed that biometrics are only useful once a child reaches two years old, so this new technology could help deliver vaccines and develop nutrition programmes for many more infants in need.

“We’re delighted that this new grant money will allow the company to scale up its exciting project at Bangladesh,” says Hanadi Jabado, Executive Director of the Entrepreneurship Centre at Cambridge Judge. “From early days on the Accelerate Cambridge programme, it was clear that Toby had a vision and strategy for Simprints to make a real difference in developing countries such as Bangladesh, along with a realization that scaling up would be an essential part of that – and this is clearly now happening.”

Simprints tested its sensor against five other commercial sensors in low-resource settings, and found that it was 228 per cent more accurate than the next best in scanning the scarred and worn fingerprints typical in some parts of the developing world. The Simprints biometric system is optimised to such conditions: the sensors, templates which encode a fingerprint’s unique characteristics, and matching algorithms are all tailored to low-resource settings, backed by data from more than 125,000 fingerprints.

“In our field tests with 217 Zambian manual farmers, 84 per cent had some damage to their fingerprints,” according to a recent article co-written by Toby in the journal Biometric Technology Today. “In standard industry evaluations of system performance, error metrics are typically measured from biometric features captured in highly controlled laboratory settings from individuals employed in non-manual work.”

By designing for context, Simprints aims to overcome the common pitfalls faced by many technology companies in the developing world. “Advanced technology is only one piece of the puzzle,” says Toby. “Effective training, an intuitive workflow, and cultural acceptability are necessary for technology to survive and grow.” In the case of Simprints, these processes were envisioned with and by community health workers at non-government organization BRAC, the same ones who in the upcoming years will be providing care to millions of mothers across Bangladesh. 

The Saving Lives at Birth partnership, which was launched in 2011, includes the Bill & Melinda Gates Foundation, the US Agency for International Development, the Norwegian Agency for Development Cooperation, Grand Challenges Canada, the U.K Department for International Development, and the Korea International Cooperation Agency.

The partnership aims to find scalable solutions to address the 303,000 maternal deaths, 2.7 million neonatal deaths, and 2.6 million stillbirths that occur each year around the world.

Originally published on the Cambridge Judge Business School website. 

The new lectureship will be funded through a gift of £1m to the Department of Land Economy by the Pecan Foundation Limited, a charity organization founded by Dr Justin Chiu. Dr. Chiu is a Senior Visiting Fellow of the Department of Land Economy, and is currently an Executive Director of Cheung Kong Asset Holdings Limited in Hong Kong. The funding will also support an ambitious new research and engagement programme in Chinese urban development.

This Lectureship represents the opening of a new phase of engagement between Cambridge's department of Land Economy and China. The Lecturer will provide teaching at undergraduate and postgraduate levels, and conduct world-leading research in sustainable development and urbanisation with a focus on China. The lecturer will also provide a focal point for collaboration and interaction with industrial leaders and research institutions throughout China.

This lectureship will address the impact of rapid population growth in China, and the demands placed on urban development. Some Chinese cities are home to populations larger than those of entire nations. The growth of these cities presents a unique opportunity to define new models and ideas for urban spaces. How these models develop will not only improve the future of cities in China, but will shape the future of urban development across the globe.

"This exciting new position will help further our understanding of the dynamics of Chinese urbanisation and its role in economic development, as well as the pressures it creates on planning and sustainability,” said Professor Colin Lizieri, Head of the Department of Land Economy. “Both our research and our teaching will benefit hugely from these insights, and the post will allow us to deepen our relationships with business leaders, policy-makers, researchers and our alumni in China and the surrounding nations." 

The team used genome editing techniques to stop a key gene from producing a protein called OCT4, which normally becomes active in the first few days of human embryo development. After the egg is fertilised, it divides until at about 7 days it forms a ball of around 200 cells called the ‘blastocyst’. The study found that human embryos need OCT4 to correctly form a blastocyst.

“We were surprised to see just how crucial this gene is for human embryo development, but we need to continue our work to confirm its role” says Dr Norah Fogarty from the Francis Crick Institute, first author of the study. “Other research methods, including studies in mice, suggested a later and more focussed role for OCT4, so our results highlight the need for human embryo research.”

Dr Kathy Niakan from the Francis Crick Institute, who led the research adds, “One way to find out what a gene does in the developing embryo is to see what happens when it isn’t working. Now we have demonstrated an efficient way of doing this, we hope that other scientists will use it to find out the roles of other genes. If we knew the key genes that embryos need to develop successfully, we could improve IVF treatments and understand some causes of pregnancy failure. It will take many years to achieve such an understanding, our study is just the first step.”

The research was published in Nature and led by scientists at the Francis Crick Institute, in collaboration with colleagues at Cambridge University, Oxford University, the Wellcome Trust Sanger Institute, Seoul National University and Bourn Hall Clinic. It was chiefly funded by the UK Medical Research Council, Wellcome and Cancer Research.

The team spent over a year optimising their techniques using mouse embryos and human embryonic stem cells before starting work on human embryos. To inactivate OCT4, they used an editing technique called CRISPR/Cas9 to change the DNA of 41 human embryos. After seven days, embryo development was stopped and the embryos were analysed.

The embryos used in the study were donated by couples who had undergone IVF treatment, with frozen embryos remaining in storage; the majority were donated by couples who had completed their family, and wanted their surplus embryos to be used for research. The study was done under a research licence and strict regulatory oversight from the Human Fertilisation and Embryology Authority (HFEA), the UK Government's independent regulator overseeing infertility treatment and research.

As well as human embryo development, OCT4 is thought to be important in stem cell biology. ‘Pluripotent’ stem cells can become any other type of cell, and they can be derived from embryos or created from adult cells such as skin cells. Human embryonic stem cells are taken from a part of the developing embryo that has high levels of OCT4.

“We have the technology to create and use pluripotent stem cells, which is undoubtedly a fantastic achievement, but we still don’t understand exactly how these cells work,” explains Dr James Turner, co-author of the study from the Francis Crick Institute. “Learning more about how different genes cause cells to become and remain pluripotent will help us to produce and use stem cells more reliably.”

Sir Paul Nurse, Director of the Francis Crick Institute, says: “This is exciting and important research. The study has been carried out with full regulatory oversight and offers new knowledge of the biological processes at work in the first five or six days of a human embryo’s healthy development. Kathy Niakan and colleagues are providing new understanding of the genes responsible for a crucial change when groups of cells in the very early embryo first become organised and set on different paths of development. The processes at work in these embryonic cells will be of interest in many areas of stem cell biology and medicine.”

Dr. Kay Elder, study co-author from the Bourn Hall Clinic, says: "Successful IVF treatment is crucially dependent on culture systems that provide an optimal environment for healthy embryo development. Many embryos arrest in culture, or fail to continue developing after implantation; this research will significantly help treatment for infertile couples, by helping us to identify the factors that are essential for ensuring that human embryos can develop into healthy babies.”

Dr Ludovic Vallier, co-author on the study from the Wellcome Trust Sanger Institute and the Wellcome - MRC Cambridge Stem Cell Institute, said: “This study represents an important step in understanding human embryonic development. The acquisition of this knowledge will be essential to develop new treatments against developmental disorders and could also help understand adult diseases such as diabetes that may originate during the early stage of life. Thus, this research will open new fields of opportunity for basic and translational applications.”

Reference:
Norah M.E. Fogarty et al. 'Genome editing of OCT4 reveals distinct mechanisms of lineage specification in human and mouse embryos.' Nature (2017). DOI: 10.1038/nature24033.

Adapted from a Francis Crick Institute press release. 

The centre, which has been built at Eddington, the University of Cambridge’s North-West Cambridge development, will be a major professional and social interactive hub for postdocs across the city. It has a 150 capacity lecture room and informal meeting space.  

Postdocs will be able to drop in for advice, networking events, research activities and other social provision.

There are just over 4,000 postdocs in Cambridge. A postdoc is a researcher who has completed their doctoral studies, and is continuing specialist research in a professional capacity in a fixed term or unestablished role.

Most are employed directly by the University, funded by research grants, or fellowships, while others are sponsored externally or by the collegiate system. At Cambridge, they conduct research into a variety of topics, including medicine, engineering, physics, the arts and social sciences.

Postdocs tend to stay at the University for between 3 and 5 years but, because of limited availability, approximately thirty per cent will go on to secure a tenured position in academia.

Karina Prasad, head of the Office of Postdoctoral Affairs, says: “This will be a flagship centre.

"Eddington is an unprecedented development that the University of Cambridge has embarked on.

"It represents a major commitment by an institution to its staff.

"Our postdocs are the future of research and are likely to make an important contribution to society. But, with increasing numbers, they face huge challenges, both professionally and personally.”

Eddington is a new development of Cambridge which is open to the whole community.

It includes housing for general sale, subsidised accommodation for the University’s key workers, as well as facilities to support the local community, including primary and nursery schools, community centre and other amenities, such as a supermarket, shops, parkland and sports fields.

Many of the University’s postdocs are likely to live at Eddington.

Postdocs come from a wide range of countries and backgrounds and often support young families.

At the moment, the community is spread out around the city and can sometimes feel disconnected from the collegiate system.

The new centre will provide a hub for postdocs’ career development activities, engagement with industry and integration with the wider University community. Their families will also find support there.

Physicist Dr Paul Coxon, vice-president of the Postdocs of Cambridge Society, says: “Postdocs come from virtually every country in the world.

"You’re constantly bumping into people from fantastically amazing backgrounds.

"It’s bringing together people from different disciplines and building up this community.

"I think this is something which is unique to Cambridge. Why would you not want to be here?”

Find out more about the Office of Postdoctoral Affairs here. 

The study, which investigated photovoltaic devices based on a type of materials called perovskites, suggests that these could achieve unprecedented levels of super-efficiency. But to do so, they will need to turn sunlight into electrons and then extract these as electrical charge within just quadrillionths of a second – a few “femtoseconds”, to give them their scientific name.

Moving electrons at this ultrafast rate would enable the creation of “hot carrier” cells. These are solar cells which can generate electricity more efficiently by making use of the added kinetic energy that electrons have for a brief moment just after they are created, while they are moving at high speed.

The amount of electrical energy that can be extracted from a hot carrier cell, relative to the amount of light absorbed, could potentially match or even break an energy efficiency rate of 30%. In rough terms, this is the maximum energy efficiency that solar cells can conceivably  achieve – although standard silicon cells typically have efficiencies closer to 20% in practice.

Despite the minuscule fractions of time involved, the authors of the new paper say that it is possible that perovskites could ultimately push this efficiency barrier.

The study, published in the journal Nature Communications, was carried out by academics in Italy and the UK. The British team involved researchers in the Cavendish Laboratory’s Optoelectronics research group of Professor Sir Richard Friend, a Fellow of St John’s College, Cambridge. The Italian team are based at the Politecnico di Milano in the group of Professor Guilio Cerullo.

Johannes Richter, a PhD student in the Optoelectronics group and the paper’s lead author, said: “The timescale that we calculated is now the time limit that we have to operate within if we want to create super-efficient, hot carrier solar devices. We would need to get electrons out before this tiny amount of time elapses.”

“We are talking about doing this extremely quickly, but it’s not impossible that it could happen. Perovskite cells are very thin and this gives us hope, because the distance that the electrons have to cover is therefore very short.”

Perovskites are a class of materials which could before long replace silicon as the material of choice for many photovoltaic devices. Although perovskite solar cells have only been developed within the past few years, they are already almost as energy-efficient as silicon.

Partly because they are considerably thinner, they are much cheaper to make. While silicon cells are about a millimetre thick, perovskite equivalents have a thickness of approximately one micrometre, about 100 times thinner than a human hair. They are also very flexible, meaning that in addition to being used to power buildings and machines, perovskite cells could eventually be incorporated into things like tents, or even clothing.

In the new study, the researchers wanted to know for how long the electrons produced by these cells retain their highest possible levels of energy. When sunlight hits the cell, light particles (or photons), are converted into electrons. These can be drawn out through an electrode to harvest electrical charge.

For a brief moment after they are created, the electrons are moving very quickly. However, they then start to collide, and lose energy. Electrons which retain their speed, prior to collision, are known as “hot” and their added kinetic energy means that they have the potential to produce more charge.

“Imagine if you had a pool table and each ball was moving at the same speed,” Richter explained. “After a certain amount of time, they are going to hit each other, which causes them to slow down and change direction. We wanted to know how long we have to extract the electrons before this happens.”

The Cambridge team took advantage of a method developed by their colleagues in Milan called two dimensional spectroscopy. This involves pumping light from two lasers on to samples of lead iodide perovskite cell in order to simulate sunlight, and then using a third “probe” laser to measure how much light is being absorbed.

Once the electrons have collided and slowed down, and are thus starting to take up space in the cell, the amount of light being absorbed changes. The time it took for this to happen in the study effectively allowed the researchers to establish how much time is available to extract electrons while they are still “hot”.

The study found that electron collision events started to happen between 10 and 100 femtoseconds after light was initially absorbed by the cell. To maximise energy efficiency, the electrons would thus need to reach the electrode in as little as 10 quadrillionths of a second.

The researchers are nonetheless optimistic that this might be possible. As well as taking advantage of the intrinsic thinness of perovskite, they believe that nanostructures could be created within the cells to reduce further the distance that the electrons need to travel.

“That approach is just an idea for now, but it is the sort of thing that we would require in order to overcome the very small timescales that we have measured,” Richter added.

The paper, Ultrafast carrier thermalization in lead iodide perovskite probed with two-dimensional electronic spectroscopy, is published in Nature Communications.

This week, UK Universities and Science Minister Jo Johnson signed the agreement with the US Energy Department to invest the sum in the Long-Baseline Neutrino Facility (LBNF) and the Deep Underground Neutrino Experiment (DUNE). DUNE will study the properties of mysterious particles called neutrinos, which could help explain more about how the universe works and why matter exists at all.

This latest investment is part of a long history of UK research collaboration with the US, and is the first major project of the wider UK-US Science and Technology agreement.

On signing the agreement in Washington DC, UK Science Minister, Jo Johnson said: “Our continued collaboration with the US on science and innovation is beneficial to both of our nations and through this agreement we are sharing expertise to enhance our understanding of many important topics that have the potential to be world changing.

“The UK is known as a nation of science and technical progress, with research and development being at the core of our industrial strategy.  By working with our key allies, we are maintaining our position as a global leader in research for years to come.” 

“The international DUNE collaboration came together to realise a dream of a game-changing program of neutrino science; today’s announcement represents a major milestone in turning this dream into reality,” said Professor Thomson. “This UK investment in fundamental science will enable us to deliver critical systems to the DUNE experiment and to provide new opportunities for the next generation of scientists to work at the forefront of science and technology.”

This investment is a significant step which will secure future access for UK scientists to the international DUNE experiment. Investing in the next generation of detectors, like DUNE, helps the UK to maintain its world-leading position in science research and continue to develop skills in new cutting-edge technologies.

The UK’s Science and Technology Facilities Council (STFC) will manage the UK’s investment in the international facility, giving UK scientists and engineers the chance to take a leading role in the management and development of the DUNE far detector and the LBNF beam line and associated PIP-II accelerator development.

Accompanying Jo Johnson on the visit to the US, Chief Executive Designate at UK Research and Innovation, Sir Mark Walport said: “Research and innovation are global endeavours. Agreements like the one signed today by the United Kingdom and the United States set the framework for the great discoveries of the future, whether that be furthering our understanding of neutrinos or improving the accessibility of museum collections.

“Agreements like this also send a clear signal that UK researchers are outward looking and ready to work with the best talent wherever that may be. UK Research and Innovation is looking forward to extending partnerships in science and innovation around the world.”

DUNE will be the first large-scale US-hosted experiment run as a truly international project at the inter-governmental level, with more than 1,000 scientists and engineers from 31 countries building and operating the facility, including many from the UK.  The US is meeting the major civil construction costs for conventional facilities, but is seeking international partners to design and build major elements of the accelerator and detectors.  The total international partner contributions to the entire project are expected to be about $500M.

The UK research community is already a major contributor to the DUNE collaboration, with 14 UK universities and two STFC laboratories providing essential expertise and components to the experiment and facility. This ranges from the high-power neutrino production target, the readout planes and data acquisitions systems to the reconstruction software.

Dr Brian Bowsher, Chief Executive of STFC, said:“This investment is a significant and exciting step for the UK that builds on UK expertise.

“International partnerships are the key to building these world-leading experiments, and the UK’s continued collaboration with the US, through STFC, demonstrates that we are the science partner of choice in such agreements.

“I am looking forward to seeing our scientists work with our colleagues in the US in developing this experiment and the exciting science which will happen as a result.”

One aspect DUNE scientists will look for is the differences in behaviour between neutrinos and their antimatter counterparts, antineutrinos, which could give us clues as to why we live in a matter-dominated universe – in other words, why we are all here, instead of having been annihilated just after the Big Bang. DUNE will also watch for neutrinos produced when a star explodes, which could reveal the formation of neutron stars and black holes, and will investigate whether protons live forever or eventually decay, bringing us closer to fulfilling Einstein’s dream of a grand unified theory.

The DUNE experiment will attract students and young scientists from around the world, helping to foster the next generation of leaders in the field and to maintain the highly skilled scientific workforce worldwide.

The Cambridge team is playing a leading role in the development of the advanced pattern recognition and computational techniques that will be needed to interpret the data from the vast DUNE detectors.

Other than Cambridge, the UK universities involved in the project are Birmingham, Bristol, Durham, Edinburgh, Imperial, Lancaster, Liverpool, UCL, Manchester, Oxford, Sheffield, Sussex and Warwick.

Adapted from an STFC press release. 

Branching patterns occur throughout nature – in trees, ferns and coral, for example – but also at a much finer scale, where they are essential to ensuring that organisms can exchange gases and fluids with the environment efficiently by the maximising the surface area available.

For example, in the small intestine, epithelial tissue is arranged in an array of finger-like protrusions. In other organs, such as kidney, lung, mammary glands, pancreas and prostate, exchange surfaces are packed efficiently around intricate branched epithelial structures.

“On the surface, the question of how these structures grow – structures that may contain as many as 30 or 40 generations of branching – seems incredibly complex,” says Professor Ben Simons, who led the study, published today in the journal Cell. Professor Simons holds positions in the University of Cambridge’s Cavendish Laboratory and Wellcome Trust/Cancer Research UK Gurdon Institute.

This classic problem of ‘branching morphogenesis’ has attracted the attention of scientists and mathematicians for centuries. Indeed, the mathematical underpinnings of morphogenesis – the biological process that causes organisms to develop their shape – was the subject of D’Arcy Wentworth Thompson's classic text, published in 1917 by Cambridge University Press. Thompson had been a student at Cambridge, studying zoology at Trinity College, and briefly worked as a Junior Demonstrator in Physiology.

During development, branching structures are orchestrated by stem-like cells that drive a process of ductal growth and division (or ‘bifurcation’). Each subsequent branch will then either stop growing, or continue to branch again. In a study published in Nature earlier this year, Professor Simons working in collaboration with Dr Jacco van Rheenen at the Hubrecht Institute in Utrecht showed that, in the mammary gland, these processes of division and termination occur randomly, but with almost equal probability.

“While there’s a collective decision-making process going on involving multiple different stem cell types, our discovery that growth occurs almost at the flip of a coin suggested that there may be a very simple rule underpinning it,” says Professor Simons.

Professor Simons and his colleague Dr Edouard Hannezo observed that there was very little crossover of the branches – ducts seemed to expand to fill the space, but not overlap. This led them to conjecture that the ducts were growing and dividing, but as soon as a tip touched another branch, it would stop.

“In this way, you generate a perfectly space-filling network, with precisely the observed statistical organisation, via the simplest local instruction: you branch and you stop when you meet a maturing duct,” says Dr Hannezo, a Sir Henry Wellcome Postdoctoral Fellow based at the Gurdon Institute. “This has enormous implications for the basic biology. It tells you that complex branched epithelial structures develop as a self-organised process, reliant upon a strikingly simple, but generic, rule, without recourse to a rigid, pre-determined sequence of genetically programmed events.”

Although these observations were based on the mammary gland epithelium, by using primary data from Dr Rosemary Sampogna at Columbia University, Professor Anna Philpott in Cambridge and Dr Rakesh Heer at Newcastle University, the researchers were able to show that the same rules governed the embryonic development of the mouse kidney, pancreas and human prostate.

“In the mammary gland, you have a hundred or more fate-restricted stem-like cells participating in this bifurcation-growth-bifurcation process, whereas in the pancreas it’s just a handful; but the basic dynamics are the same,” says Professor Simons. “The model is aesthetically beautiful, because the rules are so simple and yet they are able to predict the complex branching patterns of these structures.”

The researchers say their discovery may offer insights into the development of breast and pancreatic cancer, where the earliest stages of the disease often show an irregular tangled ductal-like organisation.

“A century after the publication of On Growth and Form, it’s exciting to see how the concepts of self-organisation and emergence continue to offer fresh perspectives on the development of biological systems, framing new questions about the regulatory mechanisms operating at the cellular and molecular scale,” Professor Simons adds.

While it may be too early to tell whether similar rules apply to other branched tissues and organisms, there are interesting parallels: branching in trees appears to follow a similar pattern, for example, with side branches growing and bifurcating until they are shaded or until they are screened by another branch, at which point they stop.

The research was funded by the Wellcome Trust with additional core support from Cancer Research UK and the Medical Research Council.

References
Scheele, C et al. Identity and dynamics of mammary stem cells during branching morphogenesis. Nature 542, 313-317 (2017); DOI: 10.1038/nature21046

Hannezo, E et al. A unifying theory of branching morphogenesis. Cell; 14 Sept 2017; DOI: TBC

Sir John Cockcroft was one of the most important and influential scientists of the modern era. He was the joint winner of the Nobel Prize for Physics (1951) for his pioneering work at the Cavendish Laboratory on the disintegration of atoms (splitting the atom).

His research facilitated the development of atomic power, nuclear medicine and accelerator science. He was the first Director of the British Atomic Energy Research Establishment at Harwell, and the first Master of Churchill College, Cambridge.

This evening, several generations of the Cockcroft family, including Sir John’s surviving children, will gather at Churchill College to celebrate the 120th anniversary of Sir John’s birth and the 50th of his death.

They will mark the occasion by handing over to the Churchill Archives Centre a family treasure trove of scrapbooks, photograph albums and hitherto unseen diaries and letters from the Western Front of World War One, illustrating the personal life of this most public scientist.

Here, it will join his Nobel Prize medal and complement his scientific papers, including his notebooks for his ground-breaking experiments which are already housed at the Archive Centre. The new material includes 400 letters to his fiancée from 1915-1919, along with a mass of later correspondence, including letters to his mother during his high powered scientific roles in the Second World War.

Other highlights include:

• Scrapbooks containing material on the Tizard mission (1940) which gave the Americans, on Churchill's orders, our scientific secrets regarding the possibility of making an atomic bomb and the newly invented cavity magnetron. Sir Henry Tizard led the mission with John Cockcroft as his deputy.
• Gamov's letter to Cockcroft of 7th September 1932, congratulating him on his discovery (first artificial disintegration of atomic nuclei).
• Sir John’s WW1 diaries from the Western Front.

After completing his first year at Manchester University, John Cockcroft left home in the summer of 1915 during World War One.  Too young to enlist, he first worked as a YMCA volunteer in an Army Camp at Abergele.  In 1916 he joined the Royal Field Artillery (RFA) as a Private. He became a signaller in the RFA and was sent to France to join the latter stages of the Battle of the Somme.

Subsequently he moved in July 1917 for the 3rd Battle of Ypres, known as Passchendaele. He survived unscathed throughout, even though many fellow soldiers in his Battery were killed or wounded. Early in 1918 he went back to England to train as an officer, which is where he was when the war ended in November 1918.

 A complete set of nearly 400 letters home exist covering the whole of this period.  Together they amount to a wonderfully descriptive and insightful account of unstinting service to his country. In addition there are some pocket diaries which he kept, despite regulations forbidding them.

Dame Athene Donald, Master of Churchill College, said: “Both as Master and as professor of Experimental Physics at the University of Cambridge, I am conscious that I owe a great personal debt to Sir John. But it is fair to say that his work has had a lasting legacy which continues to influence us all. This new material will sit alongside his existing scientific papers in the Archives Centre and will enable future generations to know the man behind the scientist.”

Christopher Cockcroft, Sir John’s son, said, “The time was right for the family to share this material and for it to be conserved for future generations to learn the full story of this remarkable man: a secondary school boy from Todmorden, who survived the First World War, and worked his way to the top of his profession; a man who firmly believed in the fellowship of man and did much to foster understanding between people and nations.”

Michael Smyth, author of a forthcoming biography of Sir John, highlighted the set of scrapbooks kept by Sir John’s mother and the many letters to his wife which together provide a unique insight into his life.

The reception and handover will take place in the Jock Colville Hall, Churchill College at from 6pm on Friday evening (September 22). All are welcome. The event will mark the beginning of the Churchill College Alumni Association Weekend, and will be the first of several events during the weekend celebrating Sir John’s life and legacy.

See https://www.chu.cam.ac.uk/events/churchill-college-association-weekend-2... for further details.

Bookings open today [25th September] for the 2017 Cambridge Festival of Ideas, which features a huge range of events and discussions on subjects ranging from empire and Brexit, the future of Europe and conspiracy theories to the past, present and future of India.

The Festival celebrates its 10th anniversary this year. It runs from 16th to 29th October with exhibitions, films, performances, talks and debates held around Cambridge, many of them free. The programme is bursting with over 200 events, a large number investigating the subject that has dominated the news over the past 12 months - truth.

Speakers include some of the world’s leading thinkers, such as the philosopher Professor Rae Langton on post-truth as post-democracy, historian Professor Richard Evans, Classics author and presenter Tom Holland, the economist Dr Ha-Joon Chang, Tristram Hunt, former Labour MP and now director of the Victorian and Albert Museum, award-winning author Pankaj Mishra, Richard Dearlove, former head of the British Secret Intelligence Service and Dame Athene Donald, Professor of Experimental Physics.

A packed programme of discussions and debates includes:

Encountering Brexit - perspectives and challenges - a panel discussion covering what Brexit means for business, international relations, education and research, domestic politics and diversity and human rights in the UK. With David Champion, senior editor at the Harvard Business Review, Hans Kundnani, Senior Transatlantic Fellow of the German Marshall Fund, Oreoluwa Ogunbiyi, President of the Cambridge University African Caribbean Society, Margret Wintermantel, President of the German Academic Exchange Service, and Professor Robert Wintermute. 27th October

Is relativism to blame for our post-truth world? - with Professor Simon Goldhill, Dr Caroline Edwards, Dr Priyamvada Gopal and Professor Frank Furedi. 21st October

Can politics keep up with technology? - Dr Beth Singler, Dr Nora Ni Loideain, Will Moy from the Full Fact correction agency and author George Zarkadakis. 21st October

Populism - populists can be sloppy with facts and speedy with promises that are impossible to deliver, but they can also highlight real inequities and persuade followers that they are in possession of some greater truth. With Dr Hugo Drochon, Dr Tanya Filer, Dr Ayca Cubukcu, Dr Nayanika Mathur and Dr Madeline Reeves. 16th October

You are what you sleep - RAND Europe discuss new research on sleep research and explain why sleep needs to be taken more seriously. 17th October

The Festival also features a number of talks and lectures, several of which related to newly released books or forthcoming projects, including:

Matt Worley, author of the new book No future: punk, politics and British youth culture 1976-1984, on the rise and significance of punk on the eve of the 40th anniversary of the release of the Sex Pistols’ groundbreaking album, Never Mind the Bollocks. 24th October

EU law expert Kenneth Armstrong, author of Brexit time: leaving the EU - why, how and when? 24th October

The return of Eastern Europe and the new Intermarium - Timothy Less, director of the Nova Europa consultancy,  explores the future of Eastern Europe and the significance of the region for Europe’s overall security and political architecture. 21st October

The 70th anniversary of Indian independence will be marked with a series of events, exhibitions and films, including a panel discussion on Indian democracy with author Pankaj Mishra [17th October], a celebration of Diwali, India’s Festival of Light, at the Botanic Garden [25th October] and India Unboxed, a specially curated series of Indian cinema, from classics to the best contemporary documentaries.

Performance and film are a key feature of the Festival. The programme features a number of experimental events designed to provoke both the brain and the senses, such as Freak Floods [25th October], which brings together harper and sonic artist Una Monaghan with vocalist Emily DeDakis in a text-sound collaboration, and Me & Robin Hood [18th October], a solo show by award-winning artistic director Shon Dale-Jones which questions the value of art and the power of story.

For art lovers, there are a host of exhibitions throughout the Festival, from Pallavi Paul’s installation Terra Firma which explores the mechanics of truth production to an exhibition of mythical beasts and supernatural beings depicted in manuscripts, rare books and magic scrolls in St John’s College’s Special Collections.

There are also hands-on event for all ages, ranging from art workshops to a family day exploring the Arctic and the animals and people who live there [21st October].

Ariel Retik, manager of the Cambridge Festival of Ideas, said: “There’s something for everyone at the Festival of Ideas, all designed to challenge people’s ideas about the world, provoke new ones and raise interesting questions for the future. The Festival spans all aspects of the human experience and this year’s theme will explore one of the biggest questions today: what does truth really mean.”

The Festival sponsors and partners are St John’s College, Anglia Ruskin University, RAND Europe, University of Cambridge Museums and Botanic Garden, Arts Council England, Cambridge Junction, The Nine Dots Prize, Cambridge Film Festival, Cambridge University Press and The Conversation. The Festival media partner is BBC Radio Cambridgeshire.

*To book ring 01223 766766.  The full programme is available here.