Culture

NIMS and AIST have developed a small sensor capable of continuously monitoring the plant hormone ethylene. Ethylene gas promotes ripening in fruits and vegetables, but excessive exposure promotes them to rot. The new small sensor can be used to monitor fruits and vegetables by continuously detecting ethylene gas, ensuring the freshness during transportation and storage, and helping reduce food waste.

Ethylene is a gaseous molecule released by fruits and vegetables as a ripening-promoting phytohormone. Fresh produce can be artificially ripened in postharvest storage by introducing ethylene into a storage facility. Continuous monitoring of ethylene concentrations in these facilities may allow the ripening progression of stored produce to be estimated more accurately, enabling optimal transportation and storage schedule. This potential benefit has led to high demand for the development of small, inexpensive ethylene sensors from the agricultural and food industries. Small sensors capable of detecting ethylene are commercially available, but many of them operate only at high temperatures (200~300 ℃). Besides, the commercially available sensors using semiconductors as sensing materials can detect other gaseous molecules (e.g., alcohol and methane) at the same time due to its highly active surface. These existing sensors therefore lack selective sensitivity to ethylene.

In this research project, we developed a small, highly sensitive sensor capable of detecting ethylene with great selectivity. This sensor consists of three components: a highly active catalyst that selectively converts ethylene into acetaldehyde, a reagent that reacts with acetaldehyde to release acidic gas and an SWCNT (single-walled carbon nanotube) electrode which is very sensitive to acidic gas (figure). This highly active catalyst can repeatedly convert ethylene into acetaldehyde as analyte-air passes through it. In addition, the catalyst can operate at near room temperature (40 ℃), making the small sensor energy efficient. The acidic gas produced by the reaction between acetaldehyde and the reagent strongly withdraws electrons from the SWCNT semiconductor, changing the semiconductor's electrical resistance. These characteristics and mechanisms enable the sensor to selectively and sensitively detect ethylene even at an extremely low concentration (0.1 ppm) by monitoring changes in electrical resistance. This sensor is expected to be effective in monitoring ethylene concentrations for many types of fresh produce in storage. For example, the ethylene concentrations that promote ripening in bananas and kiwifruit are approximately 500 ppm and 10 ppm, respectively: well within the sensor's useful sensitivity range.

This small, energy-efficient, low-cost ethylene sensor is designed to be compatible with big data integration and networking systems, and may therefore serve as a vital tool in putting Japan's super-smart society vision (the Society 5.0 initiative) into practice in the agricultural and food industries. This research group is designing different types of highly active catalysts to develop small sensors that can detect gaseous molecules other than ethylene.

The unique remains of a prehistoric, giant wombat-like marsupial - Mukupirna nambensis - that was unearthed in central Australia are so different from all other previously known extinct animals that it has been placed in a whole new family of marsupials.

Mukupirna - meaning "big bones" in the Dieri and Malyangapa Aboriginal languages - is described in a paper published today in Scientific Reports by an international team of palaeontologists including researchers from the UNSW Sydney, Salford University in the UK, Griffith University in Brisbane, the Natural History Museum in London, and the American Museum of Natural History in New York. The researchers reveal that the partial skull and most of the skeleton discovered originally in 1973 belonged to an animal more than four times the size of any living wombats today and may have weighed about 150kg.

An analysis of Mukupirna's evolutionary relationships reveals that although it was most closely related to wombats, it is so different from all known wombats as well as other marsupials, that it had to be placed in its own unique family, Mukupirnidae.

LUCKY BREAK

UNSW Science's Professor Mike Archer, a co-author on the paper, was part of the original international team of palaeontologists along with Professor Dick Tedford, another co-author, that found the skeleton in 1973 in the clay floor of Lake Pinpa - a remote, dry salt lake east of the Flinders Ranges in South Australia. He says their discovery of Mukupirna was in part due to good luck after an unusual change in local conditions exposed the 25 million-year-old fossil deposit on the floor of the dry salt lake.

"It was an extremely serendipitous discovery because in most years the surface of this dry lake is covered by sands blown or washed in from the surrounding hills," he says.

"But because of rare environmental conditions prior to our arrival that year, the fossil-rich clay deposits were fully exposed to view. And this unexpected view was breathtaking.

"On the surface, and just below we found skulls, teeth, bones and in some cases, articulated skeletons of many new and exotic kinds of mammals. As well, there were the teeth of extinct lungfish, skeletons of bony fish and the bones of many kinds of water birds including flamingos and ducks.

"These animals ranged from tiny carnivorous marsupials about the size of a mouse right up to Mukupirna which was similar in size to a living black bear. It was an amazingly rich fossil deposit full of extinct animals that we'd never seen before."

GENTLE GIANT

Professor Archer says when Mukupirna's skeleton was first discovered just below the surface, nobody had any idea what kind of animal it was because it was solidly encased in clay.

"We found it by probing the dry flat surface of the Lake with a thin metal pole, like acupuncturing the skin of Mother Earth. We only excavated downwards into the clay if the pole contacted something hard below the surface - and in this case it turned out to be the articulated skeleton of a most mysterious new creature."

The researchers' recent study of the partial skull and skeleton reveals that despite its bear-like size, Mukupirna was probably a gentle giant. Its teeth indicate that it subsisted only on plants, while its powerful limbs suggest it was probably a strong digger. However, a close examination of its features revealed the creature was more likely suited to scratch-digging, and unlikely to have been a true burrower like modern wombats, the authors say.

Lead author on the paper Dr Robin Beck from the University of Salford says Mukupirna is one of the best-preserved marsupials to have emerged from late Oligocene Australia (about 25 million years ago).

"Mukupirna clearly was an impressive, powerful beast, at least three times larger than modern wombats," he says. "It probably lived in an open forest environment without grasses, and developed teeth that would have allowed it to feed on sedges, roots, and tubers that it could have dug up with its powerful front legs."

SERIOUSLY STRANGE

Griffith University's Associate Professor Julien Louys, who co-authored the study, said "the description of this new family adds a huge new piece to the puzzle about the diversity of ancient, and often seriously strange marsupials that preceded those that rule the continent today".

The scientists examined how body size has evolved in vombatiform marsupials - the taxonomic group that includes Mukupirna, wombats, koalas and their fossil relatives - and showed that body weights of 100 kg or more evolved at least six times over the last 25 million years. The largest known vombatiform marsupial was the relatively recent Diprotodon, which weighed over 2 tonnes and survived until at least 50,000 years ago.

"Koalas and wombats are amazing animals" says Dr Beck, "but animals like Mukupirna show that their extinct relatives were even more extraordinary, and many of them were giants."

The original party that discovered Mukupirna in 1973 was an international exploration team led by Professor Dick Tedford from the American Museum of Natural History along with palaeontologists from the South Australian Museum (Neville Pledge), Queensland Museum (where Professor Archer was Curator of Fossil & Modern Mammals at the time), Flinders University (Professor Rod Wells) and the Australian Geological Survey Organisation (Mike Plane and Richard Brown).

Students can hide their ignorance and answer questions correctly in an exam without their lack of knowledge being detected by teachers - but only in the quantum world.

University of Queensland researchers have successfully verified a counterintuitive idea from quantum theory - that ignorance of the whole does not necessarily imply ignorance of the parts - in the lab.

UQ physicist Dr Jacqui Romero from the ARC Centre of Excellence for Engineered Quantum Systems (EQUS) said the team's findings would be important when evaluating security in quantum encryption.

"What's also really nice is that we provide an accessible, real-world interpretation of a statement that comes from pure probability theory," Dr Romero said.

According to classical intuition, ignorance can be traced to a source - if a student's knowledge of a book is incomplete, a teacher can design a test to probe which parts of the book are unknown to the student.

UQ PhD candidate and EQUS experimental physicist Michael Kewming said that this wasn't always the case in the quantum world.

"Our results confirm that the student's source of ignorance can be concealed from the teacher using quantum systems," Mr Kewming said.

"When we communicate, we use special symbols called letters that form an alphabet.

"In our study, we do the same thing but we use light to create a quantum alphabet."

According to Mr Kewming quantum alphabets have strange properties.

"Let's say the student is sitting an exam that covers two topics, and although they haven't studied they've been given a single hint by a knowledgeable friend," he said.

"In the classical situation, this hint can only be so helpful - providing information about only one topic - and the teacher can still uncover which topic the student is ignorant of.

"But a hint written using our quantum alphabet could simultaneously contain information about both topics, despite appearing to be about only one.

"As a result, the teacher cannot determine the source of the student's ignorance because the hint is always useful to the student."

The UQ research team was able to verify this in a physical experiment by writing information in the shape of single photons - the particles that make up light.

"Our result has implications for the security of quantum-based encryption because we have shown that what is true for classical hints is not true for quantum hints," Dr Romero said.

Unfortunately for students preparing for exams, quantum hints won't be available outside the lab anytime soon.

The results are published in Physical Review Letters.

Clinician scientists at RCSI University of Medicine and Health Sciences have begun a clinical trial of a promising therapy for critically ill COVID-19 patients in intensive care.

In a paper published in the American Journal of Respiratory and Critical Care Medicine, the team, led by RCSI Professors Gerry McElvaney and Ger Curley, describe changes in the body's normal inflammatory response in patients infected with COVID-19, in particular among those who require admission to intensive care.

The team has begun a randomised double blind placebo controlled clinical trial of alpha-1-antitrypsin to treat critically ill patients mechanically ventilated in ICU with COVID-19 associated Acute Respiratory Distress Syndrome. Alpha-1-antitrypsin is a naturally occurring human protein produced by the liver and released into the bloodstream which normally acts to protect the lungs from the destructive actions of common illnesses.

RCSI Professor of Medicine Prof. Gerry McElvaney said: "As of late June, more than 9.5 million laboratory-confirmed cases of COVID-19 have been documented globally, with over 490,000 deaths. These numbers continue to grow substantially. In Beaumont Hospital, we have had over 500 patients admitted to the hospital, and nearly 50 patients requiring admission to intensive care.

"The current management of severe COVID-19 remains supportive, focusing on supplemental oxygen and ventilator support in the event of acute respiratory failure. Despite the implications for global health, the inflammatory characteristics of patients with COVID-19 are not yet fully understood. A greater understanding of how the body's inflammatory mechanisms are impacted upon by COVID-19 could open the door to several potential therapies including antiviral medications and targeted immune-modulators such as alpha-1-antitrypsin."

Prof. Ger Curley, RCSI Professor of Anaesthesia and Critical Care and Consultant in Anaesthesia and Intensive Care in Beaumont Hospital explained that "we know from in-hospital studies that many COVID-19 patients in ICU develop severe inflammation throughout the body with a disproportionately high rate of progression to acute respiratory distress syndrome, acute renal failure, shock and heart arrhythmia."

In a collaboration between the Departments of Medicine and Critical Care and Anaesthesia, a team of clinician scientists led by Prof. McElvaney and Prof. Curley sought to ascertain the type of inflammation affecting the COVID-19 patient in ICU, and to determine whether there was a relationship between this type of inflammation and the need for intubation and mechanical ventilation.

The study showed that a number of highly inflamed proteins were all increased in infected patients compared to healthy controls. There was also a difference in the profiles of patients in ICU and those who were infected but stable.

Prof. Curley explained, however, that the most unanticipated differentiating factor between patients with stable and severe disease was not the degree of increase in inflammatory proteins, but rather the relative decrease in levels of an anti-inflammatory protein which indicates that the patients' anti-inflammatory mechanisms were failing.

"This finding suggests to us that a therapy which augments the body's own inflammation resolving mechanisms might have a positive impact. Alpha-1 protects the airway from damage during acute pulmonary infection. It is also a potent anti-inflammatory and acts to protect the immune system. Of particular relevance to COVID-19, it has been shown to modulate the production and activity of several key pro-inflammatory proteins", explained Prof. Curley.

"We are confident that this clinical trial will demonstrate the potential for Alpha-1 to improve the outcomes for patients with the most severe COVID-19 induced respiratory difficulties."

This is the first Investigational Medicine Product trial to be approved in Ireland to test a therapy to treat COVID19. The trial is being sponsored by RCSI University of Medicine and Health Sciences and is coordinated by the RCSI Clinical Research Centre. Beaumont Hospital is the first site to recruit patients and other sites in Ireland will also participate. This investigator initiated study benefited from generous support from Grifols, a Barcelona-based multinational healthcare company and a leading global producer of plasma-derived medicines, which provided access to the alpha1-proteinase inhibitor study drug.

Ranked number one globally for Good Health and Well-being in the Times Higher Education (THE) University Impact Rankings 2020, RCSI University of Medicine and Health Sciences is an international not-for-profit university, with its headquarters in Dublin.

RCSI is exclusively focused on education and research to drive improvements in human health worldwide. It is among the top 250 universities worldwide in the THE World University Rankings (2020) and its research is ranked first in Ireland for citations. RCSI has been awarded Athena Swan Bronze accreditation for positive gender practice in higher education.

Research from the University of Kent has found that people who adopt a collectivist mindset are more likely to comply with social distancing and hygiene practices to help reduce the spread of COVID-19.

People who are more individualist are less likely to engage, partly due to beliefs in COVID-19 conspiracy theories, and feelings of powerlessness surrounding the pandemic.

This study suggests the need for the UK Government and other world leaders to consider promoting collectivism amongst the general public, and to combat the spread of conspiracy theories and other types of misinformation. Doing so may increase levels of engagement in practices to help reduce the spread of COVID-19.

The research was led by Mikey Biddlestone alongside Ricky Green and Professor Karen Douglas at the University of Kent's School of Psychology. A total of 724 participants completed an online questionnaire addressing their actions relating to social distancing and hygiene measures, their individualist-collectivist mindset, feelings of powerlessness surrounding the pandemic, and their beliefs in COVID-19 conspiracy theories such as the idea that COVID-19 was made in a Chinese laboratory.

Mikey Biddlestone said: 'Interventions that focus on collective empowerment and champion a 'we are in this together' mentality could encourage people to comply with guidelines that will reduce the spread of COVID-19. Promoting collectivism could make a positive difference to future public health crises too, as leaders look to improve response strategies. A collectivist mindset might also make people less susceptible to conspiracy theories and misinformation that can negatively affect their behaviour.'

It is well-known that victims of bullying can have higher risks of future health and social problems. However, different victims experience a broad range of responses and some may not suffer at all. Researchers felt this implied there might be factors that could protect against some consequences of bullying. In a study of over 6,000 adolescents in Japan, they found a strong candidate in the moderation of what is known as emotional competence.

Online bullying, or cyberbullying, is not a new phenomenon, but as the world becomes more dependent on online communication, it does become a greater threat. Lead author Yuhei Urano, Associate Professor Ryu Takizawa and Professor Haruhiko Shimoyama from the Department of Clinical Psychology at the University of Tokyo and their team investigated protective factors for the adverse effects of cyberbullying victimization. They analyzed data from 6,403 adolescents aged 12 to 18 (1,925 male, 4,478 female) for their study.

"We chose users of a social networking app as participants of the study, because they were likely to experience more online interactions than others," said Urano. "The surveys explored instances of cyberbullying victimization and a cross section of other personal and social information. These allowed us to investigate whether the ability to handle emotions, called emotional competence, correlated with the severity of the repercussions of cyberbullying."

What the researchers found may at first seem counterintuitive, but after careful analysis, their results showed that higher emotional skills were not always associated with better mental health; they may actually make things worse depending on the social context. It depends on the individual's specific emotional competence, defined as the ability to identify, understand, express, regulate and use emotions. There is intrapersonal emotional competence, the ability to handle one's own emotions, and interpersonal emotional competence, the ability to handle others' emotions.

"We thought that intrapersonal emotional competence showed buffering effects against cyberbullying, because the ability to handle one's own emotions is known to have a positive impact on our mental health," said Urano. "On the other hand, we thought interpersonal emotional competence showed the opposite effect. Because the ability to understand emotional states in others may encourage individuals to dwell on the bully's intentions."

The researchers hope this study could pave the way to investigations about the different roles of intrapersonal and interpersonal emotional competence, both the positive and negative effects they may have. However, given the inherent complexity of the topic in question, they suggest that in order to correctly determine the causal relationships behind their results, more longitudinal studies should be conducted in the future.

The research team of Assistant Professor Masahiko Sato and Professor Yasushi Todo of the National Institutes of Natural Sciences (NINS) National Institute for Fusion Science (NIFS) has succeeded using computer simulation in reproducing the high-pressure plasma confinement observed in the Large Helical Device (LHD). This result has enabled highly accurate predictions of plasma behavior aimed at realizing an economical helical fusion reactor.

In order to realize fusion energy, we must confine high pressure plasma using the magnetic field for a long duration. Although higher pressure plasma can be confined by a stronger magnetic field, it costs more to generate a stronger magnetic field using electromagnetic coils. Therefore, if the magnetic field strength is the same, a device that can confine higher pressure plasma is economically desirable. Because the LHD has succeeded in maintaining high-pressure plasma, there is great expectation in realizing a helical fusion reactor.

Design research for a future fusion reactor is performed based on computer simulations predicting the behavior of magnetically confined plasma. We require highly accurate simulations. To confirm the accuracy, the simulations are required to reproduce the experimental results obtained by the existing devices. However, the simulations had not reproduced the experimental results obtained by the LHD showing that high-pressure plasma is maintained. This has been a serious problem for the design research for an economical helical fusion reactor.

Simulations of high-pressure plasma in the LHD had been performed using a model in which the plasma is treated as a fluid. In this fluid model, the motion averaged over many ions consisting the plasma is calculated, and the difference among many ions with various velocities are neglected. At NIFS, a program that calculates individual motions of many ions was developed to improve the simulation accuracy. This program, which is called "the hybrid simulation program," has been used to study energetic ions that will play an important role in sustaining high-temperature plasma in a future fusion reactor.

Assistant Professor Masahiko Sato and Professor Yasushi Todo attempted to reproduce high-pressure plasma confinement in the LHD by using the hybrid simulation program. They focused on the ions moving back-and-forth, which are called "trapped ions" (Image 1) and whose motion is a characteristic of the LHD. To investigate the effect of the trapped ions, the researchers studied the long-time evolution of plasma pressure and tens of millions of ions including millions of trapped ions. Although such a simulation requires enormous amounts of calculations, the researchers, by making full use of "Plasma Simulator" (the supercomputer owned by NIFS), has succeeded in reproducing the LHD experimental result showing that high-pressure plasma is maintained (Image 2). From the detailed analysis of the simulation data, it has been found that the trapped ions greatly contribute to the stable confinement of high-pressure plasma by suppressing the fluctuations that can cause the reduction of plasma pressure.

Thus, the research team has significantly improved the prediction accuracy of high-pressure plasma in a future helical fusion reactor. It is expected that the design research aimed at an economical helical reactor will be accelerated based on this study.

This research result was published as Sato and Todo "Ion kinetic effects on linear pressure driven MHD instabilities in helical plasmas" in Journal of Plasma Physics in June 2020.

Children whose fathers make time to play with them from a very young age may find it easier to control their behaviour and emotions as they grow up, research suggests.

The study, by academics at the Faculty of Education, University of Cambridge and the LEGO Foundation, pulled together fragmentary evidence from the past 40 years to understand more about how fathers play with their children when they are very young (ages 0 to 3). The researchers wanted to find out whether father-child play differs from the way children play with their mothers, and its impact on children's development.

Although there are many similarities between fathers and mothers overall, the findings suggest that fathers engage in more physical play even with the youngest children, opting for activities such as tickling, chasing, and piggy-back rides.

This seems to help children learn to control their feelings. It may also make them better at regulating their own behaviour later on, as they enter settings where those skills are important - especially school.

Paul Ramchandani, Professor of Play in Education, Development and Learning at the University of Cambridge, said: "It's important not to overstate the impact of father-child play as there are limits to what the research can tell us, but it does seem that children who get a reasonable amount of playtime with their father benefit as a group."

Dr Ciara Laverty, from the LEGO Foundation, said: "At a policy level, this suggests we need structures that give fathers, as well as mothers, time and space to play with their children during those critical early years. Even today, it's not unusual for fathers who take their child to a parent-toddler group, for example, to find that they are the only father there. A culture shift is beginning to happen, but it needs to happen more."

Parent-child play in the first years of life is known to support essential social, cognitive and communication skills, but most research focuses on mothers and infants. Studies which investigate father-child play are often small, or do so incidentally. "Our research pulled together everything we could find on the subject, to see if we could draw any lessons," Ramchandani said.

The Cambridge review used data from 78 studies, undertaken between 1977 and 2017 - most of them in Europe or North America. The researchers analysed the combined information for patterns about how often fathers and children play together, the nature of that play, and any possible links with children's development.

On average, they found that most fathers play with their child every day. Even with the smallest children, however, father-child play tends to be more physical. With babies, that may simply mean picking them up or helping them to gently raise their limbs and exert their strength; with toddlers, fathers typically opt for boisterous, rough-and-tumble play, like chasing games.

In almost all the studies surveyed, there was a consistent correlation between father-child play and children's subsequent ability to control their feelings. Children who enjoyed high-quality playtime with their fathers were less likely to exhibit hyperactivity, or emotional and behavioural problems. They also appeared to be better at controlling their aggression, and less prone to lash out at other children during disagreements at school.

The reason for this may be that the physical play fathers prefer is particularly well-suited for developing these skills.

"Physical play creates fun, exciting situations in which children have to apply self-regulation," Ramchandani said. "You might have to control your strength, learn when things have gone too far - or maybe your father steps on your toe by accident and you feel cross!"

"It's a safe environment in which children can practise how to respond. If they react the wrong way, they might get told off, but it's not the end of the world - and next time they might remember to behave differently."

The study also found some evidence that father-child play gradually increases through early childhood, then decreases during 'middle childhood' (ages 6 to 12). This, again, may be because physical play is particularly important for helping younger children to negotiate the challenges they encounter when they start to explore the world beyond their own home, in particular at school.

Despite the benefits of father-child play, the authors stress that children who only live with their mother need not be at a disadvantage.

"One of the things that our research points to time and again is the need to vary the types of play children have access to, and mothers can, of course, support physical play with young children as well," Ramchandani added. "Different parents may have slightly different inclinations when it comes to playing with children, but part of being a parent is stepping outside your comfort zone. Children are likely to benefit most if they are given different ways to play and interact."

Gold mining significantly limits the regrowth of Amazon forests, greatly reducing their ability to accumulate carbon, according to a new study. The researchers warn that the impacts of mining on tropical forests are long-lasting and that active land management and restoration will be necessary to recover tropical forests on previously mined lands.

Gold mining has rapidly increased across the Amazon in recent years, especially along the Guiana Shield, where it is responsible for as much as 90% of total deforestation. The Shield encompasses Guyana, Suriname, French Guiana, Venezuela and small parts of Colombia and northern Brazil, and its forests hold roughly twenty billion tonnes of aboveground carbon in its trees.

The ability of tropical forests to recover from gold mining activities has remained largely unquantified. Now, an international study led by the University of Leeds is the first to provide detailed field-based information on the regeneration of forests in Guyana after gold mining, and the first ground-based estimate of carbon sink lost as a result of gold mining activities across the Amazon.

The team's findings, published in the Journal of Applied Ecology, found that forest recovery rates on abandoned mining pits and tailing ponds are amongst the lowest ever recorded for tropical forests. At some sites there was nearly no tree regeneration even after three to four years since mining had stopped.

They estimate that mining-related deforestation results in the annual loss of over two million tons of forest carbon across the Amazon. The lack of forest regrowth observed following mining suggests that this lost carbon cannot be recovered through natural regeneration.

Lead author Dr Michelle Kalamandeen, began this research as a postgraduate researcher in the School of Geography at Leeds she is now a postdoctoral researcher at Cambridge University. She said: "This study shows that tropical forests are strongly impacted by mining activities, and have very little capacity to re-establish themselves following mining.

"Our results clearly show the extraction process has stripped nitrogen from the soil, a critical component to forest recovery, and in many cases directly contributed to the presence of mercury within neighbouring forests and rivers. Active mining sites had on average 250 times more mercury concentrations than abandoned sites.

"Not only does this have serious consequences for our battle against global warming by limiting Amazonian forests' ability to capture and store carbon, but there is also a larger implication of contaminating food sources especially for indigenous and local communities who rely on rivers.

"A positive finding from this study shows that overburden sites, areas where topsoil is deposited during the mining process, recorded similar recovery rates as other Central and South American secondary tropical forests abandoned after agriculture or pasture.

"Active management and enforcement of laws is clearly needed to ensure recovery and to safeguard communities and there are methods available, such as replacing the soil using the overburdens at abandoned sites. But there is an urgent need for large-scale recovery management to be tested and implemented.

"We could be facing a race against the clock. The current crisis is significantly increasing the demand for gold, given its perceived role as an economic stabiliser. With current gold price more than US$1700 per ounce and estimated to reach US$2000-3000 in the coming months, many artisanal and small-scale miners are already rapidly responding to this increase in pricing, and the weakening of environmental laws and policies as we've seen in Brazil, leading to further deforestation in the Amazon."

The team used forest inventory plots installed on recently abandoned mines in two major mining regions in Guyana, and re-censused the sites 18 months later. The study analysed soil samples and determined individual trees' above-ground biomass - the tree's living plant material - to determine recovery and chemical changes caused by mining.

Their results suggest that forest recovery is more strongly limited by severe mining-induced depletion of soil nutrients, especially nitrogen, rather than by mercury contamination. The high rate of mercury does however have serious implications for negative impacts on food security, water supply and local biodiversity.

Study co-author, Dr David Galbraith, Associate Professor in Earth System Dynamics at Leeds, said: "Currently approximately 1.3 million square kilometres of the Amazon is under prospecting for mining activities.

"This research provides support to local and national governance structures to critically approach policy implementation and development for land management, including how and where mining occurs, and more stringent monitoring and action for forest recovery. It shows that carefully planned active restoration projects will be critical in this regard.

"But responsibility lies beyond remediation efforts to mitigate the damage done. Investors and consumers alike need increased awareness and accountability of the environmental footprints of gold mining."

The Guyana Geology and Mines Commission (GGMC) who supported the fieldwork are optimistic that the results from this research will help in making more informed decisions for their reclamation policies and programmes, monitoring and enforcement.

Mr Newell Dennison, Commissioner of the GGMC said: "The research results showed two important aspects: that overburden areas recovered relatively well and there was limited recovery in mining pits and tailing ponds. The latter being areas where we need improved management. The more data we can accumulate for recovery of secondary forests in mined out areas, the better we are all positioned for the implementation of effective programmes and operations that aid in the recovery of our rainforests. We look forward to working with Dr Kalamandeen and her team in the future."

The Guyana Forestry Commission (GFC) expressed gratitude and appreciation to the research team for the important and impressive empirical work done in [this] paper.

Mr Gavin Agard, Commissioner of the GFC said: "We expect that this scientific work has greatly improved Guyana's baseline and understanding of the forest degradation impacts of mining with respect to biomass recovery and sets a foundation for more dynamic, focused studies to advise planning and policy for improving secondary forest growth and restoring biomass capacity.

"The findings and recommendations from this study will significantly impact policy and management strategies for forest restoration and rehabilitation in mined-out areas, which is a key objective for Guyana under the Paris Agreement of the UNFCCC.

"The contribution of deforestation and degradation to climate change cannot be ignored, and thus we welcome the contributions of this research team to build and improve our communal knowledge and understanding of our changing forests as we continue to pursue the highest standards of sustainable forestry in Guyana."

VANCOUVER, Wash. - Fears of confirming stereotypes about pregnant workers as incompetent, weak or less committed to their job can drive pregnant employees to work extra hard, risking injury.

A recent Washington State University study of pregnant women in physically demanding jobs showed that the majority, about 63%, felt this type of "stereotype threat," the fear of confirming negative assumptions about a group to which they belong. The study, published in the journal Work & Stress, found this threat led many women to conceal their pregnancy and overperform, even taking actions that placed their health and pregnancy at risk, such as standing for long periods or lifting heavy objects.

The study shows the need to acknowledge that these stereotypes exist and help mitigate their impacts, said Lindsey Lavaysse, lead author on the paper and recent WSU Ph.D. graduate.

"The pregnancy stereotype is a silent stressor. It is not always visible, but it really impacts women in the workplace," said Lavaysse. "Most organizations have policies for pregnancy accommodation in place, and it's a legal right, but if the organization's culture suggests there will be retaliation or that workers will be looked upon differently, then women will shy away from using accommodations that are better for their health and their safety."

Lavaysse and co-author Tahira Probst, a WSU professor of psychology, surveyed pregnant employees at three separate points in time over a two-month period, starting with a group of about 400. The subjects were at different stages in their pregnancy and worked in a variety of industries, including manufacturing, health care and retail.

The researchers looked at workplace accidents of women who reported feeling a low versus high stereotype threat. The individuals who reported a higher stereotype threat had nearly three times as many work-related accidents at the end of the two-month period compared to those who felt a relatively low stereotype threat.

Moreover, fears of confirming these stereotypes also increased over the two-month period.

"Two months is a relatively small window of time, but in the scheme of a pregnancy that's close to one whole trimester," said Lavaysse. "As they're progressing through their pregnancy, their experience of stereotype threat, a significant stressor, is also increasing."

The researchers note some limitations to the study, namely that the participants were self-selected, and many dropped out before the two months were over. However, this is the first study to establish a connection between pregnancy stereotype threat and workplace accidents.

The authors recommend further research that investigates possible variables that may mitigate some of the negative stigma around pregnancy while working and create better social support for utilizing pregnancy accommodation and maternal leave policies.

It only takes a moment to fall off a ladder, but the psychological impacts are long-lasting, particularly for older males.

In the world's first study of long-term impacts from ladder falls, Queensland researchers have found half of fallers experience a deterioration in their psychological wellbeing for at least six months after the incident.

The University of Queensland's Dr Rob Eley said those who fell experienced sleeping problems, anxiety, depression and pain well after checking out of hospital.

"Ladder falls go far beyond that of the physical injury; they significantly impact a person's mental health and the whole family," Dr Eley said.

"It's frustrating because ladder-related falls are frequently preventable, yet they're a common cause of injuries presented at the emergency department.

"Our study found males over 55 years old are particularly at risk, making up more than half of all our ladder-related fall cases."

The researchers followed 134 Queenslanders who presented to emergency at Princess Alexandra and Nambour General Hospitals between October 2015 and October 2016 as a result of a fall from a ladder.

The team used the Assessment of Quality of Life (AQoL) scale to measure the subjects' physical and psychological recovery over time.

The patients spent an average of five days in hospital with the most common injuries including spinal fractures, rib fractures, tibia or fibula fractures, radius or ulna fractures, pelvic fractures, and traumatic pneumothorax.

The study found that most injuries occurred in non-occupational settings during home maintenance.

Of those who were employed at the time, 80 per cent required at least four weeks off work, and 16 per cent were unable to return or perform their normal function after six months.

Dr Eley said the study highlighted the need for improved safety designs and injury prevention strategies.

"Our research reinforces the need for mandated safety instructions for ladders, as well as safety features like rubber feet, hooks, extender arms, fasteners and stabilisers," Dr Eley said.

"We suggest that at the place of purchase, older men are targeted to reinforce safety instructions, and perhaps are provided with mandatory stabilising features.

"The community also needs to do more to educate people that it's OK to request help or employ home service contractors to complete tasks around the home that require a ladder.

"Ladder falls are frequently preventable and our findings demonstrate the need for preventative measures to be taken."

Prof. TIAN Chao's group from the Department of Precision Machinery and Instrumentation, University of Science and Technology of China (USTC) of the Chinese Academy of Sciences (CAS) has made progress on the photoacoustic imaging for medical science. They improved the imaging quality and 3D construction of the photoacoustic imaging, and applied them to in vivo sentinel lymph node imaging. The studies were published in IEEE Transactions on Biomedical Engineering, Physical Review Applied and Journal of Biophotonics.

Sentinel lymph node biopsy (SLN) is currently the standard method for breast cancer staging, which includes preoperative lymph node tracing and intraoperative lymph node biopsy image-guiding. However, existing image guidance techniques suffer from a variety of limitations, such as harmful ionizing radiation, high cost, and poor imaging depth.

To solve these problems, Prof. TIAN's group proposed a contract-agent-enhanced photoacoustic imaging method, which used clinically-approved carbon nanoparticles as a contrast agent to trace SLN and guide fine needle aspiration biopsies, non-invasively and non-radioactively.

The researchers injected carbon nanoparticles (CNPs) into the forepaws of living rats to stain SLN. Subsequently, photoacoustic and ultrasound dual-modality imaging were performed simultaneously in real-time at the axillary area of the rats to trace the SLN and guide the biopsy.

Experiments showed that photoacoustics can image and display lymphatic vessel, lymph nodes, needles, etc. with high resolution and high signal-to-noise ratio, which can provide high-quality image guidance for lymph node biopsy.

In addition, spectroscopic analysis showed that CNPs are superior to indocyanine green, methylene blue and other contrast agents in optical absorption coefficient, photobleaching and photoacoustic conversion efficiency. It is an excellent tracer for identifying SLN by photoacoustic imaging and image-guided biopsies.

This study provides a practical approach for fine-needle aspiration biopsy in the SLN tracing and image guidance, and paves the way for clinical translation of photoacoustic SLN imaging.

Prediction of storm surges and peak wave heights using advanced high-resolution modeling reveals the important role of offshore reefs in protecting coastal zones. The findings by KAUST researchers provide valuable design criteria for city planning in the King Abdullah Economic City (KAEC) coastal zone and highlight the economic and disaster-mitigating imperative to conserve the Red Sea's coral reefs.

"The original task was to model the maximum wave heights to set the minimum safe floor elevation for structures and roadway design in the city," says Sabique Langodan from KAUST's Red Sea Modeling and Prediction Group. "Yet with the wealth of wave and water-level observations and accurate bathymetry (water depth) near the coastline, combined with the advanced modeling and supercomputing capabilities available to us at KAUST, we extended the study to investigate the role of coral reefs in modulating the wave climate of this reef-sheltered region."

To accurately predict extreme wave heights it is necessary to model how waves transform as they pass across reefs and the shallow sea floor using long-term wave data. Many inputs go into the simulation, including a model of the physical wave transformation process, bathymetry, atmospheric forcing and sea circulation. Just as important, however, is the simulation architecture and the computational platform because they determine the resolution and accuracy of the results.

"We configured a high-resolution model using an unstructured grid, which allows us to vary the resolution of the model over the domain, from 60 kilometer cells out to sea, to cells as small as 60 meters near the coastline," says Langodan.

The researchers used a coupled wave and circulation model to account for changes in wave heights resulting from variations in water levels and currents. They combined this with meteorological fields derived from a high-resolution regional atmospheric model.

"Our high-resolution study allowed the minimum safe elevation in KAEC to be revised lower, from 4.0 meters to 2.3 meters," says group leader Ibrahim Hoteit. "Although a relatively small drop, this leads to a saving of about 90 million cubic meters of fill material equating to about 500 million USD."

However, the study also showed that the lowered safe elevation depends on the presence of the coral reefs located off the Red Sea coast, which act as a natural breakwater to provide protection to coastal areas against hazards, such as wave runup, overtopping, flooding and erosion.

"The reefs reduce wave heights by half at the coastline," says co-author Omar Knio. "Reef?protected coastlines could still be at risk of larger waves if the coastal protection offered by reefs is reduced by coral degradation or sea level rise."

Neuroscientists and stem cell researchers at Lund University in Sweden have developed a research model that allows studying human hippocampal neurons, the brain cells primarily affected by Alzheimer's disease pathology. The study has been published in Stem Cell Reports.

In Alzheimer's disease the hippocampus, a brain structure that regulates motivation, emotion, learning, and memory, is severely affected. However, due to unavailability of hippocampal tissue, unless post-mortem, it is not possible for researchers to understand what the primordial events that lead to cellular dysfunction, and subsequent neuronal injury, are. Understanding what cellular pathways are altered very early on in Alzheimer's disease, would allow the development of therapies that could slow down the disease.

Researchers in Lund have succeeded to generate 3-D hippocampal tissue-like structures from induced pluripotent stem cells (iPSC), called hippocampal spheroids (HS). The spheroids are enriched in so-called granule neurons.

In most vertebrate species, including humans, new granule neurons are generated throughout life via a process called neurogenesis and they are believed to contribute to memory formation. The new method developed by the scientists will enable scaling up the production of hippocampal neurons to study human neurogenesis, and, most importantly, examine how human hippocampal cells, including granule neurons and supporting glia, may be affected very early on in Alzheimer's disease and disorders where the hippocampus is injured.

"By using patient iPSC, we can generate young brain cells and examine early pathogenic changes, and gain valuable insight into the development and progression of brain diseases", explains Laurent Roybon, director of the Stem Cell Laboratory for CNS Disease Modeling at Lund University and one of the researchers behind the study.

Understanding patient-specific pathology

The researchers also used HS to examine cellular dysfunction in Alzheimer's disease and more precisely, how cellular pathogenesis differed between individuals. They generated HSs from patients with extreme symptomatology - a typical Alzheimer´s patient carrying a mutation in the amyloid precursor protein gene, and an atypical individual carrying a rare mutation in the presenilin 1 gene - and examined the cellular pathology.

"Interestingly, we found that despite exhibiting some important common features, the HSs from the two mutants differed in many other characteristics, which somewhat was reflecting the severity of their symptoms", explains Yuriy Pomeshchik, lead author of the new study.

Hippocampal spheroids can serve multiple purposes

The work developed in Dr. Roybon´s laboratory opens up new possibilities, as it serves multiple purposes:

"HSs can be used to understand how hippocampal cells generate and mature over time. They can also be used to examine if the neurogenesis is affected in HSs generated from patients with hippocampal injury compared to control individuals. The analysis of HSs can reveal what cellular dysfunctions take place early on in the disease, and if they are identical or differ between patients carrying familial or idiopathic forms. HSs could be harnessed to develop treatments tailored to subgroups of patients as well as to understand why some treatments may or may not be beneficial for them. Ultimately, HSs could allow examining the effectiveness of a putative treatment prior to being administered, in addition to being used as a way to sub-group individuals for clinical trial, and recruit putative responders. We believe that HSs will be an important tool to develop therapies and provide patients with the best treatment possible", says Laurent Roybon.

"We employed HSs to examine the effect of a gene called NeuroD1, which we have been studying extensively for years. Viral-mediated expression of NeuroD1 was sufficient to increase the level of synaptic genes, whose levels are affected in Alzheimer's disease. Improving synaptic transmission will be key to resolving impaired cognition in Alzheimer's disease", says Yuriy Pomeshchik.

"We will pursue our efforts to generate spheroids from patients diagnosed with neurodegenerative diseases, and use them to gain insights into early cellular dysfunction to pinpoint at disease-specific and relevant targets for therapeutic intervention. We will also push, to bring NeuroD1 gene therapy to clinical trial", concludes Laurent Roybon.

Using similar methodology, the researchers also generated midbrain spheroids containing dopaminergic neurons to identify early metabolic dysfunctions in Parkinson's disease cells (Chumarina et al, Acta Neuropathologica Communications, 2019).

Changes to lockdown measures in the UK and around the world in an effort to restart the economy could lead to wide disparity in how the public adheres to social distancing, according to a new report from psychologists at the University of Bath.

In a paper published in the British Journal of Social Psychology, the researchers warn of emerging tensions that will arise between groups who interpret messages about social distancing in different ways and the challenge this poses to policymakers.

They suggest that in March, strict lockdown guidelines supported by legal and policy changes, meant that most people adhered to the same mitigating practices including isolation and distancing.

Now that lockdown is easing in many parts of the world, with policies becoming more ambiguous, many practices now need to be negotiated on an interpersonal level, they argue. This means that ensuring compliance will increasingly rely on informal, social policing between individuals: both for those who do, versus those who do not uphold social distancing.

Over recent weeks in the UK, scenes of packed sunny beaches have filled newspapers, leading some to question the sense of others, labelled 'covidiots'. For the researchers this is a sign of mixed messaging surrounding the relaxation of lockdown with different interpretations by individuals.

They warn that morally blaming individuals for the impact of their behaviour on the pandemic - as evidenced in the recent threat to close beaches - may detract from a much-needed discussion over whether guidelines are fit for purpose and their effect on infection rates.

Equally, they draw attention to moral challenges faced by others who wish to maintain strict distancing or isolation and the challenges they now face under pressure to socialise without wanting to appear rude or overdramatic. The researchers suggest that how individuals continue to differently interpret public health messages about COVID-19 will lead to increased tensions between groups moving further into summer.

Lead researcher Annayah Prosser from the Department of Psychology at the University of Bath explains: "Strict lockdown guidelines meant that until recently everyone was adhering to the same mitigating practices such as isolation and distancing. However, now that lockdown is easing, and policy is becoming more ambiguous, many practices now need to be negotiated on an interpersonal level. For example, at the height of lockdown you didn't need to decline an invitation to a social gathering, because it was technically against the law. Now, if you decline an invitation, you could be perceived as rude, or as a 'do-gooder' who thinks they're better than everyone else."

In their report, the team outline how this person-to-person informal regulation poses difficulties for people who want to continue to maintain strict practices over time, who may increasingly face social derogation and ostracism from others who behave differently.

Annayah Prosser added: "Our main recommendation for individuals is to avoid portraying others as morally 'good' or 'bad' for their actions. People may have complex reasons for their behaviour, that may not be visible on sight or through a short social media post. These choices are tough and simplifying behaviour as 'good' or 'bad' without knowing the full story could lead to increased tensions and polarisation at a time when communities need to work together constructively to address the crisis."